An open coaxial re-entrant microwave sensor has been used for the
non-invasive and continuous monitoring of the sol–gel transition of
physical gels characterized by different gelation mechanisms, solvents,
compositions, and stabilities. Comparison of measurements by
differential scanning calorimetry allowed the identification of the
phase transition by a change in the dielectric properties of the
material over time.
Self-assembled viscoelastic gels of organic solvents (organogels), water
(hydrogels) or water–organic solvent mixtures (aqueous gels) have been
recognized as promising materials for bottom-up nanofabrication tools in
various fields including biomedicine, sensors, cosmetics, food,
catalysis, and environmental remediation.As soft materials, gels are
continuous in structure and solid-like in rheological behavior. In
contrast to chemical gels, which are based on covalent bonds (usually
cross-linked polymers unable to redissolve), physical (also called
supramolecular) gels are made of either low-molecular-weight (LMW)
compounds or polymers – so called gelators – through extensive
non-covalent interactions, predominantly hydrogen-bonding, van der
Waals, dipole–dipole, charge-transfer, donor–acceptor, π–π stacking and
metal-coordination interactions. Furthermore, systems based on both
types of connections are also known. The solid-like appearance of these
gels is the result of the entrapment of the liquid (major component) in
the interstices of a solid 3D matrix of large surface area (minor
component), usually through surface tension and capillary forces.
Remarkably, many gels can immobilize up to 105 solvent molecules per
molecule of gelator and increase the viscosity of the medium by a factor
of 1010.
In the case of LMW gelators, the formation of the viscoelastic matrix is
a consequence of the entanglement of 1D supramolecular fibers
(typically of micrometer scale lengths and nanometer scale diameters),
which is usually induced by cooling their hot isotropic solutions to
room temperature (RT). However, it should be noted that gelation of
liquids at RT or induced by ultrasound treatment instead of
heating–cooling has also been described. Due to the weakness of the
non-covalent interactions that maintain the dynamic supramolecular
structure, physical gels are usually thermoreversible. Moreover, the
sol–gel (and/or gel–sol) phase transition could also be triggered by
other stimuli such as pH, light irradiation or ionic strength if the
gelator molecule possesses appropriate structural moieties for
recognition. It is also important to recognize that the metastable
nature of physical gels derives from an elusive equilibrium between
dissolution and crystallization, which has stimulated numerous studies
and applications in the field of crystal engineering during the last few
years.
Due to the brittleness of these materials, it is usually easier to
monitor the gel–sol transition rather than the sol–gel for the
construction of phase diagrams according to both the gel–sol transition
temperature (TGS) and the sol–gel transition temperature (TSG). Among
different techniques, rheology, NMR spectroscopy and conventional
differential scanning calorimetry (DSC) are the most common and accurate
methods used so far for this kind of study, albeit they normally suffer
from the disadvantages of being relatively time consuming and requiring
the use of very expensive equipments and trained personnel. Techniques
of higher specificity such as ESR, NIR and fluorescence spectroscopy
have also been used to characterize the sol–gel transitions of
colloids.17 On the other hand, dielectric measurements have also been
used to determine sol–gel transitions, usually below a few kHz. At these
frequencies the dielectric properties are normally related to the
conductive nature of the material and this quantity becomes (less)
sensitive to chemical changes that occur at gelation.Dielectric
measurements at microwave frequencies, however, are very sensitive to
the mobility of molecules in the gel (especially when some water dipoles
are involved). Therefore, the use of the mobility of the molecular
structure through dielectric properties provides a direct (and in situ)
measurement of the chemical and physical state of the matter.Changes in
dielectric parameters can be related to critical points in different
material processes, such as cure reaction onset, gelation, end-of-cure,
build-up of the glass-transition temperature, etc.For example, a
microwave system designed for adhesive cure monitoring has been
previously described by some of us where in situ dielectric measurements
correlate very well with conventional measurement techniques such as
DSC, combining accuracy and rate with simplicity and an affordable cost.
This communication presents a microwave non-destructive system for
monitoring the sol–gel transition process of supramolecular gels (Fig.
1A). A microwave sensor adapted to a standard pyrex vial containing the
precursor isotropic solution allows in situ measurements of dielectric
properties in order to distinguish the changes over time and
temperature.
Fig. 1B shows a picture of the portable microwave device used to conduct
the dielectric measurements. The system comprises a microwave sensor, a
microwave transmitter and receiver (from 1.5 to 2.5 GHz) and a control
unit to provide real-time information about the gelation progress
without interfering with the reaction. The precursor isotropic solution
is introduced in a pyrex vial and placed inside an open coaxial
re-entrant (microwave) cavity sensor. When the low-intensity
electromagnetic waves penetrate into the material, its molecules tend to
orient with the (applied) external field and the material gains certain
polarization, reflecting the back part of the microwave signal from the
sensor. This reflected signal is measured continuously to determine the
resonance frequency and quality factor of the sensor during gelation to
monitor the transition process. Fig. 1C and D show a typical response
of the reflected signal in the microwave cavity sensor in the imaginary
plane (Smith chart) or in magnitude representation of a gelation
experiment at a given temperature. We have reported elsewhere the
fundamental details of the microwave system with a different sensor
head.
Fig. 2 shows the library of known gelators that we prepared (ESI) to
test the ability of the microwave sensor to monitor the sol–gel
transition of physical gels. The library included single LMW gelators
(1–8) as well as bicomponent (9) and multicomponent gelator systems
(10). A number of gels with different solvents and compositions could be
easily obtained from this library at well-defined concentrations.
Moreover, N,N′-dibenzoyl-L-cystine (6) was included in this study for
the preparation of aqueous gels. Azobenzene-containing peptide 8 was
selected because its phase transition can be triggered either thermally
or photochemically. Besides the classical heating–cooling treatment
needed for the formation of thermoreversible physical gels made from
solid compounds 1–8, gelator systems 9 and 10 enable sol–gel phase
transitions at RT and well below RT, respectively. In the case of 9, DMF
stock solutions of oxalic acid dihydrate and copper(II) acetate
monohydrate were mixed at RT to form the corresponding organogel.
Multicomponent solution 10 constitutes a special system used to form
organogels at low temperatures upon addition of a small amount of this
solution to a suitable organic solvent (ESI). In contrast to the gels
obtained from 1–8, those derived from 9–10 are not thermoreversible
despite the non-covalent interactions involved in the gelation process.
Moreover, gels made from 10 eventually undergo subsequent transition to a
thermodynamically most stable crystallization phase This collection of
gelators offered a versatile scenario for the proof-of-concept of the
detection of the sol–gel transition in physical gels by continuously
monitoring the dielectric properties of the materials.
The isotropic solutions of the gelators were prepared as previously
reported (ESI). Preliminary experiments with solutions prepared at
different concentrations of a LMW gelator showed a response of the
microwave sensor to viscosity changes of the medium (ESI). On the basis
of this observation, the dielectric properties of the sol–gel transition
were continuously monitored at microwave frequencies and the obtained
profile was correlated with the actual temperature of the material
(ESI). Moreover, DSC thermograms were recorded separately for model
systems in order to draw meaningful comparisons between the change in
the dielectric properties of the material and the exothermic effect
associated with the sol–gel transition. The temperature profiles during
the sol–gel period were constructed independently by means of a
thermocouple probe (∅ 0.1 mm) centrally placed inside the mixture. We
confirmed that the use of this probe did not affect the gelation
kinetics. After each measurement, the state of the material was examined
by the “stable-to-inversion” test, and the gel condition of model
samples that did not show gravitational flow upon turning the vial
upside-down was also confirmed by oscillatory rheological measurements
(ESI).
The results indicated a good correlation between the different
techniques to recognize the sol–gel transition under different
conditions (e.g., solvent nature, concentration, and gelator structure).
Finally, preliminary experiments have shown that the microwave sensor
could also be used to detect the melting (gel–sol) transitions as we
could record the variation of the dielectric properties of the material
at single points (upon heating separately) and correlate marked changes
with the TGS determined by DSC or the inverse flow method (ESI).
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年7月27日星期三
2016年7月20日星期三
Microwave sensor detects changes in heart rate
Current medical
techniques for monitoring heart rate and other vital signs use electrodes
attached to the body, but these are impractical to use on patients that move
around.
Plasma physicist Atsushi Mase, a scientist atKyushu University in Japan
The system uses very weak microwaves to irradiate – and scatter off – the human body. A microwave sensor then monitors the reflected waves, which change in phase in response to motions of the body, including the regular displacement of the chest during breathing or, the slight movement of the chest caused by the beating heart.
’The skin surface moves slightly, synchronising to respiration and heartbeat,’ said Mase.
Using signal processing algorithms and techniques to filter out the effects of random body motions, Mase and Nagae were able to detect changes in heart rate in near real time.
’We plan to apply the system to various conditions, including for clinical use – such as for the overnight monitoring of vital human signs – and as a daily health monitor, including detecting signs of sleepiness in drivers and preventing stress-related illnesses,’ added Mase.
Plasma physicist Atsushi Mase, a scientist at
The system uses very weak microwaves to irradiate – and scatter off – the human body. A microwave sensor then monitors the reflected waves, which change in phase in response to motions of the body, including the regular displacement of the chest during breathing or, the slight movement of the chest caused by the beating heart.
’The skin surface moves slightly, synchronising to respiration and heartbeat,’ said Mase.
Using signal processing algorithms and techniques to filter out the effects of random body motions, Mase and Nagae were able to detect changes in heart rate in near real time.
’We plan to apply the system to various conditions, including for clinical use – such as for the overnight monitoring of vital human signs – and as a daily health monitor, including detecting signs of sleepiness in drivers and preventing stress-related illnesses,’ added Mase.
2016年7月14日星期四
Macphie of Glenbervie and Censis complete microwave sensors trial
The two organisations have successfully trialled a pilot scheme using
microwave sensors designed by the university. These sensors are located in the
company’s UHT production plant, which manufactures a broad range of ambient
stable food products such as sweet and savoury sauces, glazes, dairy cream
alternatives and desserts.
Pipes are flushed with water for cleaning between products and, to retain
sterility of the plant, the current process relies on timers to judge when
product has fully displaced water and can start to be packed off. This creates
a significant amount of waste, which leaves scope to improve efficiency.
The research project – facilitated by Censis, the Scottish Innovation
Centre for Sensor and Imaging Systems – developed a new, patented microwave sensor that can detect, to within a second, the presence of a pure product in
the process, displacing all water.
The patented system will now be deployed full-scale in the Macphie
production process line, which Ashley Baker, head of research and development
at Macphie of Glenbervie, said would deliver three major benefits:
- more efficient new product
development
- improved efficiency of production
- reduced environmental impact.
- “Our success in a market dominated by a number of very large players is because of our ability to offer new, more convenient and high quality products,” said Baker. “That requires innovation through R&D, which is at the heart of everything we do.
“This project is a significant step for us and allows us to be more
flexible and responsive to the changing demands of the market and our
customers. It will help us produce more efficiently, lessen our impact on the environment through reduced waste, and increase
our production yields. It will also make it easier for us to switch production
from product to product and make developing new products a much more efficient
process.”
2016年6月30日星期四
Wadeco MWS-ST/SR type microwave sensor for blocked chute detection
As well as its use for level detection, microwave technology is now
being applied across many industries for applications such as the
detection of blocked chutes, flow/no-flow detection, the detection of
product on conveyors, the detection of blocked pneumatic conveying pipes
and the detection of blocked air slides.
The Wadeco MWS-ST/SR-type microwave sensor is a switch consisting of a transmitter (MWS-ST) and a receiver (MWS-SR) installed face to face. The transmitter emits a continuous, low-power microwave beam towards the receiver and an output relay is released when the beam is obstructed.
With the microwave sensor’s non-invasive installation methods, there is no disruption to material flow and the process can be kept closed. Microwave sensors are also unaffected by build-up on the antenna head, due to the high penetrability of microwaves. With the series 3, the range can now extend up to 200 m.
Microwave sensors are also unaffected by environmental conditions including heavy dust and airborne particles, smoke, vapour, flames, rain, snow etc.
Microwave sensors have a wide application across all areas of industry where highly reliable, non-contact detection is required. They are generally used for process control by monitoring presence/absence of product, flow/no flow conditions and point-level detection in bins and silos.
With no moving parts and non-contact detection, the result is reduced wear and tear, zero maintenance and added safety for personnel and operators.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
The Wadeco MWS-ST/SR-type microwave sensor is a switch consisting of a transmitter (MWS-ST) and a receiver (MWS-SR) installed face to face. The transmitter emits a continuous, low-power microwave beam towards the receiver and an output relay is released when the beam is obstructed.
With the microwave sensor’s non-invasive installation methods, there is no disruption to material flow and the process can be kept closed. Microwave sensors are also unaffected by build-up on the antenna head, due to the high penetrability of microwaves. With the series 3, the range can now extend up to 200 m.
Microwave sensors are also unaffected by environmental conditions including heavy dust and airborne particles, smoke, vapour, flames, rain, snow etc.
Microwave sensors have a wide application across all areas of industry where highly reliable, non-contact detection is required. They are generally used for process control by monitoring presence/absence of product, flow/no flow conditions and point-level detection in bins and silos.
With no moving parts and non-contact detection, the result is reduced wear and tear, zero maintenance and added safety for personnel and operators.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年6月29日星期三
Smart Microwave Sensors For Critical Site Protection
Sensitive and
protected area such as oil fields, power plants, airports, borders, ports,
embassies, military and government sites, correctional facilities, industrial
and commercial installations, and VIP residences are critical sites that
necessitate very efficient protection against criminal or terroristic attacks.
The classic protection systems commonly used for infrastructure protection, such as barbed wire fences and perimeter security microwave sensors with a low level of smartness and flexibility, are often highly obtrusive and not definitively unassailable. A clever solution to many of the drawbacks associated with security devices currently on the market, most of which are based on cameras, could consist of a wireless sensor network (WSN) of smart radar sensors (SRS) with a high level of reconfigurability and robustness to physical and cyber-attacks.
Innovative technologies are moving toward highly miniaturized and integrated radar sensors suitable to be easily embedded or concealed in the site protection infrastructure.
SRS networks are capable of detecting multiple intruder simultaneously and allow fully radar detection capability in all light and weather conditions along with continuous tracking of each detected target. Furthermore, the classification of the target and then of the intruder (armed or disarmed) will be facilitated using polarization agility and artificial neural network methods.
The classic protection systems commonly used for infrastructure protection, such as barbed wire fences and perimeter security microwave sensors with a low level of smartness and flexibility, are often highly obtrusive and not definitively unassailable. A clever solution to many of the drawbacks associated with security devices currently on the market, most of which are based on cameras, could consist of a wireless sensor network (WSN) of smart radar sensors (SRS) with a high level of reconfigurability and robustness to physical and cyber-attacks.
Innovative technologies are moving toward highly miniaturized and integrated radar sensors suitable to be easily embedded or concealed in the site protection infrastructure.
SRS networks are capable of detecting multiple intruder simultaneously and allow fully radar detection capability in all light and weather conditions along with continuous tracking of each detected target. Furthermore, the classification of the target and then of the intruder (armed or disarmed) will be facilitated using polarization agility and artificial neural network methods.
2016年6月21日星期二
More Microwave Sensors To Keep Midtown Traffic "In Motion"
The DOT's "Midtown in Motion" congestion management system will double
in size, growing from a 110-block zone to a 270-block service area. The
innovative system launched last July, and the DOT says it's resulted in
an overall 10% improvement in travel times on the avenues. Using 100
microwave sensors, 32 traffic video cameras and E-ZPass readers at 23
intersections to measure traffic speeds, engineers in the DOT’s Traffic
Management Center (TMC) have been able to spot congestion as it occurs
and use "networked Advanced Solid State Traffic Controllers (ATSC) to
remotely adjust Midtown traffic signal patterns" and unplug bottlenecks.
The expansion will include an additional 110 microwave sensors, 24 traffic video cameras, and 36 E-ZPass readers, and will become fully operational this September. According to an announcement from the DOT, the service area will more than double in size to include Midtown, from 1st to 9th avenues and from 42nd to 57th streets. The expansion will cost $2.9 million, with $580,000 coming from the city, and the rest from New York State. Another $2 million is being invested in 200 new ASTCs, $1.6 million of that from the Federal Highway Administration and the remainder from the city taxpayers.
The data from the sensors and cameras is transmitted wirelessly in real time to the TMC in Long Island City, where engineers make constant adjustments to traffic signals. The real-time Midtown in Motion traffic information is also available on DOT’s website, on smartphones and tablets (and is also accessible to app developers).
Midtown's bike network is also getting an upgrade as part of the DOT's bike lane expansion. The DOT plans to install four new pairs of crosstown bike lanes through Midtown; if approved, the lanes would be tightly spaced, located on 39th and 40th Streets, 43rd and 44th, 48th and 51st, and 54th and 55th. Head on over to Streetsblog for a closer look at the lanes' "odd" design.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
The expansion will include an additional 110 microwave sensors, 24 traffic video cameras, and 36 E-ZPass readers, and will become fully operational this September. According to an announcement from the DOT, the service area will more than double in size to include Midtown, from 1st to 9th avenues and from 42nd to 57th streets. The expansion will cost $2.9 million, with $580,000 coming from the city, and the rest from New York State. Another $2 million is being invested in 200 new ASTCs, $1.6 million of that from the Federal Highway Administration and the remainder from the city taxpayers.
The data from the sensors and cameras is transmitted wirelessly in real time to the TMC in Long Island City, where engineers make constant adjustments to traffic signals. The real-time Midtown in Motion traffic information is also available on DOT’s website, on smartphones and tablets (and is also accessible to app developers).
Midtown's bike network is also getting an upgrade as part of the DOT's bike lane expansion. The DOT plans to install four new pairs of crosstown bike lanes through Midtown; if approved, the lanes would be tightly spaced, located on 39th and 40th Streets, 43rd and 44th, 48th and 51st, and 54th and 55th. Head on over to Streetsblog for a closer look at the lanes' "odd" design.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年6月16日星期四
How does microwave sensor cooking work?
Microwave sensor cooking uses temperature and humidity sensors inside
the microwave to determine when the food is ready. When a microwave
heats food, it excites the water in the food, causing it to give off
steam as it heats. Sensor cooking monitors the temperature and amount of
steam coming from the food to judge how much water remains and how long
it should continue heating.
Sensor cooking first requires the user to select the type of food to cook and sometimes to enter the weight or amount to be heated. Different types of food contain different moisture levels, so the amount of steam given off by popcorn varies significantly from the amount given off by broccoli. Without knowing what type of food is being cooked, the sensor cannot make an accurate judgment about when the food is ready to eat and may cause the microwave to undercook or overcook the food.
Sensor cooking is not foolproof. For instance, agricultural products may vary in their moisture content, so a particularly dry or moist vegetable may give different results when using sensor cooking. Users should follow food safety guidelines when using this system and check that the food has been thoroughly cooked before dining.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
Sensor cooking first requires the user to select the type of food to cook and sometimes to enter the weight or amount to be heated. Different types of food contain different moisture levels, so the amount of steam given off by popcorn varies significantly from the amount given off by broccoli. Without knowing what type of food is being cooked, the sensor cannot make an accurate judgment about when the food is ready to eat and may cause the microwave to undercook or overcook the food.
Sensor cooking is not foolproof. For instance, agricultural products may vary in their moisture content, so a particularly dry or moist vegetable may give different results when using sensor cooking. Users should follow food safety guidelines when using this system and check that the food has been thoroughly cooked before dining.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年5月27日星期五
Commercial Microwave Sensor Technology: An Emerging Business
Based
on a market study conducted by Intechno Consulting, the world sensor market
(all sensing principles) is growing steadily with an average annual growth rate
of seven percent from $20 B in 1994 to $40 B by 2004. An emerging
segment of this huge market is related to microwave sensors. According to
market forecasts from Frost & Sullivan and ABI Inc., radar applications are
expected to build to a $1 B market within five years, as shown in Figure 1
. Clearly, the commercial microwave sensor market is experiencing a boom. Radar
technology provides what the market needs: a reliable, accurate and noncontact
sensing of distance, movement and presence.
segment of this huge market is related to microwave sensors. According to
market forecasts from Frost & Sullivan and ABI Inc., radar applications are
expected to build to a $1 B market within five years, as shown in Figure 1
. Clearly, the commercial microwave sensor market is experiencing a boom. Radar
technology provides what the market needs: a reliable, accurate and noncontact
sensing of distance, movement and presence.
Industrial
Sensors
A significant
industrial application of radar sensor technology is the measurement of liquid
or solid material level in process tanks. Most level measurement principles
require a mechanical contact to the process, but use of contactless measurement
principles is increasing rapidly. Radar offers the best performance in terms of
robustness to extreme temperature, pressure, dust and aggressive chemicals.
World revenues from shipments of radar level-sensing instruments are growing 15
percent per year and are expected to reach $280 M by 2003.
New
competitors are currently entering this market, creating a market growth that
puts price pressure on radar level-sensing instruments, which originally were
high profit products. The majority of installed radar level meters operate at
5.8 and 10 GHz. However, the next generation of radar systems with 24 GHz
technology pose strong competition to the existing products for two reasons:
The 24 GHz level gauge can be built smaller and lighter. Hence, it can be
mounted to narrow tank flanges and is much easier to handle. In addition, sharp
antenna patterns that maximize the level echo while minimizing disturbing
reflections are possible, providing high accuracy and measurement reliability.
The
new 24 GHz systems not only utilize advanced microwave technology, they also
incorporate modern digital signal processing (DSP) features such as
self-calibration, self-diagnosis and automatic parameter setup, which provide
the user with easy installation and low maintenance. Besides level sensing,
radar technology is used in several industrial niche applications such as
turbine diagnosis, moisture measurement in paper production and object
detection within manufacturing lines. Figure 2 shows an increasingly common
contactless measurement gauge.
Automotive
Sensors
In the
automotive industry, a highly competitive car market exists. Advanced features
are used to distinguish cars while safety is a major consideration in new car
purchases. It is not surprising that radar technology has gained strong support
from leading members of the automobile industry. The automotive radar market is
expected to dynamically grow to a volume of roughly $300 M to $500 M by 2003.
The
revolutionary approach of automotive distance warning systems is to use
front, side and backup radar systems to monitor obstacles, as shown in Figure
3 . This car vision system determines distance from and speed of detected
objects and alerts drivers if they are too close to an obstacle. Radar appears
to be the best sensor principle since alternatives such as laser and ultrasound
fail under bad weather conditions when they are needed most.
front, side and backup radar systems to monitor obstacles, as shown in Figure
3 . This car vision system determines distance from and speed of detected
objects and alerts drivers if they are too close to an obstacle. Radar appears
to be the best sensor principle since alternatives such as laser and ultrasound
fail under bad weather conditions when they are needed most.
The
first 77 GHz adaptive cruise control (ACC) radar was scheduled to be available
in Mercedes Benz S-class cars this spring. Besides the forward-looking radar,
increasing interest is being expressed in short-distance sensor functions such
as lane-change aid, park distance control (PDC), precrash detection, occupant
sensing and a stop-and-go option for second-generation ACC radar systems. It is
not yet clear at which frequencies these novel automotive sensors will operate,
but the 24 GHz band could be a good choice with respect to production maturity
and cost. The in-car sensor functions are likely to be realized using an
optical basis.
The
parking aid is a well-established car option that was introduced by BMW in
1991. All PDC systems shipped currently are based on an ultrasonic principle.
However, ultrasound is likely to be replaced as soon as radar is offered at the
same price level. As a customer benefit, radar is more robust and the microwave
modules are mounted invisibly behind the bumper.
Airbag
systems are another potential application for radar and light detection and
ranging technology. Conventional airbag systems are triggered by acceleration
or pressure sensors. Sophisticated signal processing is required to determine
very quickly whether or not an accident occurred and at what time the airbags
must be deployed. A precrash detection using radar could help to further
improve the reliability of airbags, especially with respect to the side airbag,
which is the most critical type. An additional idea behind adaptive inflation
of the so-called smart airbag is the use of an in-car sensor to determine the
shape and position of the occupant on each seat. The technology for future
optical three-dimensional (3-D) camera chips for passenger detection is
currently in development.
Although
the car sensor functions discussed in this article are not yet completely
mature, it is not difficult to imagine microwave and optical vision systems
making their way into future automobiles. A survey of the automobile industry
has determined that an appropriately priced device designed to reduce
collisions could become as popular as other safety devices such as airbags and
automatic braking systems, which have gained an impressive market share.
Consumer
Sensors
Consumer
applications, a very fragmented market, have put the strongest price pressure
on sensor devices. The sensor element is only a small portion of the end
product. Here, radar again competes with less-expensive principles such as
ultrasound and infrared sensors. Despite the technical advantages of radar, it
cannot be successful unless ultra-low cost microwave sensor elements become
feasible.
The
most popular radar application is motion sensing. Typical end-customer products
are door openers and automatic light switches. Microwave sensors can be mounted
invisibly behind dielectric covers, which is a clear advantage over other
technologies. Radar motion sensors have been available for some time and it is
now possible to produce a simple planar 2.4 or 5.8 GHz Doppler radar module for
roughly $5. However, this cost is still higher than an IR sensor. The
semiconductor industry is working on radar chips capable of operation to 100
GHz. In parallel, optical 3-D camera technology is being established. The
higher the frequency, the better the sensor resolution and the smaller and
cheaper the sensor element can be. The industrial, scientific and medical band
at 61 GHz would be suitable for low cost sensors such as proximity switches.
Future
$3 sensor elements will open up the market for interesting products in
household applications. An intelligent home environment may contain functions
ranging from smart doors and lights, enhanced safety alarm features, wireless
identification and data transmission to more sophisticated products such as 3-D
imaging cameras for cleaning robots and smart cooking.
2016年5月18日星期三
Microwave Sensors for Industrial Applications
Neither of production control systems can do without sources of original
information, namely, sensors monitoring the behaviour of process
equipment. Push-button-relay control panels are replaced with micro-
processor-based process control systems demonstrating the highest
performance and reliability characteristics. Sensors are furnished with
digital communication interfaces, however, this does not always result
in the improvement of the general reliability and veracity of the system
operation. It can be explained by the fact that the very principles of
operation of the majority of the known sensor types dictate the
necessity for active constraints concerning the conditions of sensor
application.
The main function of a process control system is in the precise observance of feedstock processing technology and feedstock conversion into end product. In addition to continuous equipment monitoring and prevention of emergency situations a competently designed system must keep track of the product handling within the complete chain of processing machinery.
Technological processes intended for the modification of the chemical composition of feedstock, in-stream blending of various materials, wetting, etc. in case of loss of any component must provide for the reliable cut-off of the rest. Spring-loaded plates with microswitches are still in use for the control of availability of a product flow. In operation they are exposed to continuous shock impacts of humid and aggressive environment that naturally results in "freezing" of contacts or mechanical failure of plates.
Thus, the absence of reliable and cheap sensors for monitoring of industrial machinery and equipment results in the decline of the efficiency of production control systems, and poorer return of funds invested in automation. Sophisticated and expensive process control systems based on conventional types of sensors are only suitable for convenient group switch-on/switch-off of processing circuits, and in many cases they are not able to improve the quality of products and to save feedstock and resources.
The necessity for continuous maintenance, control and adjustment of sensors results in downtime: for the removal of the stuck product from a capacitance sensor it is necessary to discharge a bunker, to prepare and to install a winch for the personnel access to the bunker, on completion of the maintenance process it is necessary to adjust the device; for the replacement of a velocity pick-up or drag-type sensor on a continuous-bucket elevator the complete disassembly of the elevator boot is required. As a rule it takes several hours that brings down the production rate of a facility as a whole.
Several years ago the above mentioned problems gave rise to the development of radically new types of devices, namely, radar velocity pickups, mechanical motion and backup-pressure transducers, which operation is based on the interaction of the controlled item with a nearly 1010 Hz frequency radio signal.
Application of microwave methods of process equipment monitoring is completely free from the disadvantages of conventional-type sensors. Moreover, new devices successfully eliminate the earlier unsolved problems faced by process engineers and automation departments, as well as control and measuring instruments and automatic equipment sections.
The peculiar features of these devices are as follows:
• absence of a mechanical or electrical contact with an item (medium), the distance between a sensor and an item may be several meters;
• direct monitoring of an item (conveyor belt, chain) itself rather than its drive, tension drum, etc;
• low energy intensity;
• insensitivity to product sticking due to large working distances;
• high interference immunity and precise directivity of operation;
• air-tight design;
• once-only tuning for the entire service life;
• high reliability, safety, the device is free from ionizing radiation.
The right part of the table presents a list of microwave sensors for industrial automatics, which are commercially manufactured by the PromRadar research and production company, while the left part reflects the application areas of these devices.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
The main function of a process control system is in the precise observance of feedstock processing technology and feedstock conversion into end product. In addition to continuous equipment monitoring and prevention of emergency situations a competently designed system must keep track of the product handling within the complete chain of processing machinery.
Technological processes intended for the modification of the chemical composition of feedstock, in-stream blending of various materials, wetting, etc. in case of loss of any component must provide for the reliable cut-off of the rest. Spring-loaded plates with microswitches are still in use for the control of availability of a product flow. In operation they are exposed to continuous shock impacts of humid and aggressive environment that naturally results in "freezing" of contacts or mechanical failure of plates.
Thus, the absence of reliable and cheap sensors for monitoring of industrial machinery and equipment results in the decline of the efficiency of production control systems, and poorer return of funds invested in automation. Sophisticated and expensive process control systems based on conventional types of sensors are only suitable for convenient group switch-on/switch-off of processing circuits, and in many cases they are not able to improve the quality of products and to save feedstock and resources.
The necessity for continuous maintenance, control and adjustment of sensors results in downtime: for the removal of the stuck product from a capacitance sensor it is necessary to discharge a bunker, to prepare and to install a winch for the personnel access to the bunker, on completion of the maintenance process it is necessary to adjust the device; for the replacement of a velocity pick-up or drag-type sensor on a continuous-bucket elevator the complete disassembly of the elevator boot is required. As a rule it takes several hours that brings down the production rate of a facility as a whole.
Several years ago the above mentioned problems gave rise to the development of radically new types of devices, namely, radar velocity pickups, mechanical motion and backup-pressure transducers, which operation is based on the interaction of the controlled item with a nearly 1010 Hz frequency radio signal.
Application of microwave methods of process equipment monitoring is completely free from the disadvantages of conventional-type sensors. Moreover, new devices successfully eliminate the earlier unsolved problems faced by process engineers and automation departments, as well as control and measuring instruments and automatic equipment sections.
The peculiar features of these devices are as follows:
• absence of a mechanical or electrical contact with an item (medium), the distance between a sensor and an item may be several meters;
• direct monitoring of an item (conveyor belt, chain) itself rather than its drive, tension drum, etc;
• low energy intensity;
• insensitivity to product sticking due to large working distances;
• high interference immunity and precise directivity of operation;
• air-tight design;
• once-only tuning for the entire service life;
• high reliability, safety, the device is free from ionizing radiation.
The right part of the table presents a list of microwave sensors for industrial automatics, which are commercially manufactured by the PromRadar research and production company, while the left part reflects the application areas of these devices.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年5月13日星期五
Label free detection of specific protein binding using a microwave sensor
The specific binding of streptavidin to biotinylated protein A was demonstrated using a microwave detection system.
In control experiments, the degree of non-specific binding was negligible. The method of detection was used to monitor the adsorption of two other proteins, cytochrome c and glucose oxidase, on to the IDE microwave sensor surface.
The response of the sensor was also examined on different substrate materials, with detection of protein binding observed obtained on both smooth, conductive (gold) and on rough, insulating (hydroxyapatite) surfaces.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
In control experiments, the degree of non-specific binding was negligible. The method of detection was used to monitor the adsorption of two other proteins, cytochrome c and glucose oxidase, on to the IDE microwave sensor surface.
The response of the sensor was also examined on different substrate materials, with detection of protein binding observed obtained on both smooth, conductive (gold) and on rough, insulating (hydroxyapatite) surfaces.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年5月12日星期四
A Review of Industrial Microwave Sensors
This paper reviews the field of microwave sensors. The field is broad
and the applications numerous. This review will therefore only be able
to present the broad outlines.
Firstly the historical perspective and the physical background are briefly described, and the general advantages and disadvantages are listed.
An overview of the various working principles of microwave sensors is given with a few examples of the applications mentioned. Important fields of applications and interesting examples are treated separately, starting with the measurement of moisture, which is the single most important field of applications in microwave sensors.
Applications in the petroleum industry are also mentioned, because they are relatively new, they play an exceptionally important economical role, and represent the field in which the author is currently working. Followed by some trends for the future.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
Firstly the historical perspective and the physical background are briefly described, and the general advantages and disadvantages are listed.
An overview of the various working principles of microwave sensors is given with a few examples of the applications mentioned. Important fields of applications and interesting examples are treated separately, starting with the measurement of moisture, which is the single most important field of applications in microwave sensors.
Applications in the petroleum industry are also mentioned, because they are relatively new, they play an exceptionally important economical role, and represent the field in which the author is currently working. Followed by some trends for the future.
ISweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年5月5日星期四
Using Microwave Sensors to Measure Moisture Levels in Mozzarella Cheese
In the food
production industry, there are strict health and safety regulations in place to
ensure that consumers receive a product that is of superior quality. The
ramifications of not meeting these government and industry standards can be
hugely detrimental to a food producer. If poor-quality food were to make it to
market, it can cause illness to the consumer resulting in legal consquences for
the manufacturer. On the other hand, food that does not pass quality standards
can result in wasted materials, higher manufacturing costs, and ultimately a
loss in revenue.
When it comes to cheese manufacturing, being able to measure the moisture and temperature of the material are critical parameters for meeting quality standards. The amount of water that is contained in cheese can greatly affect its quality, processing, and shelf life.This article will explore the benefits of relying on microwave frequencies and RF resonators to accurately measure the moisture of soft cheeses, in particular mozarella, and includes a case study that gives manufacturers real-world guidelines for setting up a microwave resonator-based sensor to measure the moisture of cheese.
Benefits of Microwave Resnoator Sensors for Cheese Production
Using a microwave sensor solution, cheese manufacturers can obtain a precise measurement data for calculating the moisture, or water content, of mozarella. By accurately measuring moisture, microwave RF sensors help manufacturers reduce the growth of bacteria, helping a company achieve the highest quality product. Microwave sensors can also be used to make other measurements, such as weight, density, and temperature, as well as identify foreign particles or substances that have come into contact with the cheese. For this article, we will concentrate exclusively on the benefits of measuring moisture, since this is the most critical measurement at hand.
There are several characteristcs about advanced microwave-based sensors that make them the ideal solution for measuring the moisture content of cheese. One benefit is that they enable manufacturers to take a precise measurement within a small area. Using the microwave resonator technique, RF sensors can detect the moisture level percentage of a product as small as 2-3 cm. The measurement field always stays inside the material compared with capacitive sensors, which use a larger measurement area and therefore often measure outside of the substance.
Microwave measurements also offer the advantage of being able to detect the moisture at both the surface and core of the product. This makes it easier to measure challenging products, for example, those that may be dried at the surface only. It can be difficult to measure those types of products with capacitive and optical measuring methods.
Microwave resonator-based sensors also meet cheese manufacturers requirements for in-line measurements, as the sensors can be installed directly on the production line. For production lines with wide conveyor belts measuring 1 meter or more, several sensors can be used in a row. Using inline sensors, manufacturers can eliminate the need to use a probe and measure one-off samples in a laboratory, which is the traditional way of performing moisture measurements. With inline sensors, manufacturers can take an immediate measurement from the production line; no preparation of samples is needed. This method is significantly faster, uniquely handling microwave frequencies of up to 65 GHz at a rate of up to 10,000 measurements per second. In addition, it is infinitely more accurate, with industry research showing that accuracy increases when a measurement is taken inline vs. laboratory samples.
When it comes to cheese manufacturing, being able to measure the moisture and temperature of the material are critical parameters for meeting quality standards. The amount of water that is contained in cheese can greatly affect its quality, processing, and shelf life.This article will explore the benefits of relying on microwave frequencies and RF resonators to accurately measure the moisture of soft cheeses, in particular mozarella, and includes a case study that gives manufacturers real-world guidelines for setting up a microwave resonator-based sensor to measure the moisture of cheese.
Benefits of Microwave Resnoator Sensors for Cheese Production
Using a microwave sensor solution, cheese manufacturers can obtain a precise measurement data for calculating the moisture, or water content, of mozarella. By accurately measuring moisture, microwave RF sensors help manufacturers reduce the growth of bacteria, helping a company achieve the highest quality product. Microwave sensors can also be used to make other measurements, such as weight, density, and temperature, as well as identify foreign particles or substances that have come into contact with the cheese. For this article, we will concentrate exclusively on the benefits of measuring moisture, since this is the most critical measurement at hand.
There are several characteristcs about advanced microwave-based sensors that make them the ideal solution for measuring the moisture content of cheese. One benefit is that they enable manufacturers to take a precise measurement within a small area. Using the microwave resonator technique, RF sensors can detect the moisture level percentage of a product as small as 2-3 cm. The measurement field always stays inside the material compared with capacitive sensors, which use a larger measurement area and therefore often measure outside of the substance.
Microwave measurements also offer the advantage of being able to detect the moisture at both the surface and core of the product. This makes it easier to measure challenging products, for example, those that may be dried at the surface only. It can be difficult to measure those types of products with capacitive and optical measuring methods.
Microwave resonator-based sensors also meet cheese manufacturers requirements for in-line measurements, as the sensors can be installed directly on the production line. For production lines with wide conveyor belts measuring 1 meter or more, several sensors can be used in a row. Using inline sensors, manufacturers can eliminate the need to use a probe and measure one-off samples in a laboratory, which is the traditional way of performing moisture measurements. With inline sensors, manufacturers can take an immediate measurement from the production line; no preparation of samples is needed. This method is significantly faster, uniquely handling microwave frequencies of up to 65 GHz at a rate of up to 10,000 measurements per second. In addition, it is infinitely more accurate, with industry research showing that accuracy increases when a measurement is taken inline vs. laboratory samples.
2016年4月26日星期二
Microwave Sensor Applications in Industry
Microwave measuring methods can be applied to determine the
properties of materials and hence it is possible to develop microwave sensorsfor processing industry. The first applications were in moisture measurement
but lately many new sensor applications have appeared.
Microwave sensors especially suitable in forest industry
(wood, paper), in chemical industry (plastics, chemicals), in food industry
(tobacco, butter) etc. In developing sensors several problems must be solved.
The dielectric properties of the material in question must be known. They can
be measured or in some cases determined theoretically by applying mixing
theories.
The sensor is often some kind of a resonator. Its structure
must be such that the electric field penetrates the material as required, and
allows free flow of material. Displacements occurring normally in the material
flow or dirt in the sensor must not cause measuring errors. Several examples of
lately developed sensors are given.
2016年4月19日星期二
Using Microwave Sensors to Measure Moisture Levels in Mozzarella Cheese
In the food
production industry, there are strict health and safety regulations in place to
ensure that consumers receive a product that is of superior quality. The
ramifications of not meeting these government and industry standards can be
hugely detrimental to a food producer. If poor-quality food were to make it to
market, it can cause illness to the consumer resulting in legal consquences for
the manufacturer. On the other hand, food that does not pass quality standards
can result in wasted materials, higher manufacturing costs, and ultimately a
loss in revenue.
When it comes to cheese manufacturing, being able to measure the moisture and temperature of the material are critical parameters for meeting quality standards. The amount of water that is contained in cheese can greatly affect its quality, processing, and shelf life.This article will explore the benefits of relying on microwave frequencies and RF resonators to accurately measure the moisture of soft cheeses, in particular mozarella, and includes a case study that gives manufacturers real-world guidelines for setting up a microwave resonator-based sensor to measure the moisture of cheese.
Benefits of Microwave Resnoator Sensors for Cheese Production
Using a microwave resonator-based sensor solution, cheese manufacturers can obtain a precise measurement data for calculating the moisture, or water content, of mozarella. By accurately measuring moisture, microwave RF sensors help manufacturers reduce the growth of bacteria, helping a company achieve the highest quality product. Microwave sensors can also be used to make other measurements, such as weight, density, and temperature, as well as identify foreign particles or substances that have come into contact with the cheese. For this article, we will concentrate exclusively on the benefits of measuring moisture, since this is the most critical measurement at hand.
There are several characteristcs about advanced microwave sensors that make them the ideal solution for measuring the moisture content of cheese. One benefit is that they enable manufacturers to take a precise measurement within a small area. Using the microwave resonator technique, RF sensors can detect the moisture level percentage of a product as small as 2-3 cm. The measurement field always stays inside the material compared with capacitive sensors, which use a larger measurement area and therefore often measure outside of the substance.
Microwave measurements also offer the advantage of being able to detect the moisture at both the surface and core of the product. This makes it easier to measure challenging products, for example, those that may be dried at the surface only. It can be difficult to measure those types of products with capacitive and optical measuring methods.
Microwave resonator-based sensors also meet cheese manufacturers requirements for in-line measurements, as the sensors can be installed directly on the production line. For production lines with wide conveyor belts measuring 1 meter or more, several sensors can be used in a row. Using inline sensors, manufacturers can eliminate the need to use a probe and measure one-off samples in a laboratory, which is the traditional way of performing moisture measurements. With inline sensors, manufacturers can take an immediate measurement from the production line; no preparation of samples is needed. This method is significantly faster, uniquely handling microwave frequencies of up to 65 GHz at a rate of up to 10,000 measurements per second. In addition, it is infinitely more accurate, with industry research showing that accuracy increases when a measurement is taken inline vs. laboratory samples.
When it comes to cheese manufacturing, being able to measure the moisture and temperature of the material are critical parameters for meeting quality standards. The amount of water that is contained in cheese can greatly affect its quality, processing, and shelf life.This article will explore the benefits of relying on microwave frequencies and RF resonators to accurately measure the moisture of soft cheeses, in particular mozarella, and includes a case study that gives manufacturers real-world guidelines for setting up a microwave resonator-based sensor to measure the moisture of cheese.
Benefits of Microwave Resnoator Sensors for Cheese Production
Using a microwave resonator-based sensor solution, cheese manufacturers can obtain a precise measurement data for calculating the moisture, or water content, of mozarella. By accurately measuring moisture, microwave RF sensors help manufacturers reduce the growth of bacteria, helping a company achieve the highest quality product. Microwave sensors can also be used to make other measurements, such as weight, density, and temperature, as well as identify foreign particles or substances that have come into contact with the cheese. For this article, we will concentrate exclusively on the benefits of measuring moisture, since this is the most critical measurement at hand.
There are several characteristcs about advanced microwave sensors that make them the ideal solution for measuring the moisture content of cheese. One benefit is that they enable manufacturers to take a precise measurement within a small area. Using the microwave resonator technique, RF sensors can detect the moisture level percentage of a product as small as 2-3 cm. The measurement field always stays inside the material compared with capacitive sensors, which use a larger measurement area and therefore often measure outside of the substance.
Microwave measurements also offer the advantage of being able to detect the moisture at both the surface and core of the product. This makes it easier to measure challenging products, for example, those that may be dried at the surface only. It can be difficult to measure those types of products with capacitive and optical measuring methods.
Microwave resonator-based sensors also meet cheese manufacturers requirements for in-line measurements, as the sensors can be installed directly on the production line. For production lines with wide conveyor belts measuring 1 meter or more, several sensors can be used in a row. Using inline sensors, manufacturers can eliminate the need to use a probe and measure one-off samples in a laboratory, which is the traditional way of performing moisture measurements. With inline sensors, manufacturers can take an immediate measurement from the production line; no preparation of samples is needed. This method is significantly faster, uniquely handling microwave frequencies of up to 65 GHz at a rate of up to 10,000 measurements per second. In addition, it is infinitely more accurate, with industry research showing that accuracy increases when a measurement is taken inline vs. laboratory samples.
2016年3月15日星期二
Microwave Sensors vs Infrared Sensors
Automatic lighting controls work by sensing when an area is occupied,
the level of daylight or both. They then switch lighting on or off or
dim the level.
There are two main ways for sensors to detect when an area is occupied:
Microwave sensors transmit an inaudible microwave and monitor reflections from walls or objects in the room irrespective of heat or light. Line of sight issues do not affect microwave sensors as any movement of solid objects changes the pattern of the reflections and activates the sensor.
Key points:
• Activated by motion – speed and size not heat and light
• Unaffected by background temperature
• Completely enclosed within the lighting fixture as microwave operation can safely penetrate non-metallic objects such as glass and plastic
• Very stable performance which is suitable for any climate
• In line with the fittings IP rating, the units are dust and smoke proof as they are inside the fitting
• Very long life span of 100,000 hours plus
Passive infrared (PIR) sensors relate to the movement of objects by detecting their heat and light, but only in their field of view. As these products rely on line of sight their performance is affected when inanimate objects obstruct their field of view.
Key points:
• Activated by infrared – heat and light
• Do not function well in temperatures >35 degrees Celsius
• Cannot penetrate plastic or glass, so the detector has to be positioned externally to a light fitting, therefore they can become vulnerable to smoke and dust
• Lenses can age due to exposure to the atmosphere, which results in reduced performance over time
• Short life span of around 20,000 hours
The cutting edge microwave sensors used by Netlec.co.uk in a new generation of light fittings, such as the Lunar 2D wIth Microwave Sensor have numerous benefits:
• Purpose made for use in intelligent light fittings to suit energy saving applications
• Turn on when presence is detected, then dim down for a pre-set time to a lower percentage of brightness once the presence has passed
• The sensor is unobtrusive as it is located inside the light fitting, so there is no compromise to decoration or room design
• Extremely low transmission power equivalent to only 2% of that of a typical mobile phone
• Multi-operational settings which are variable to suit the user
• Wide operating temperature range of between -35 deg to +70 deg Celsius
• Replaceable rim trims with a range of colour options to suit the decor of the room
The Lunar 2D wIth Microwave Sensor is an Energy saving surface mounted flight fitting complete with a cutting edge integral microwave occupancy/light sensor. The fitting has been designed for Netlec.co.uk specifically to enhance their offering of energy saving products.
Fittings with microwave sensors are ideally suited to areas which only need to be illuminated when occupied and daylight diminishes below the required level. They are perfect for use in a wide variety of environments, where energy efficiency is of prime importance, for instance corridors, stairways, storage areas, toilets etc. Popular in schools and commercial premises, the Lunar 2D wIth Microwave Sensor is aesthetically pleasing enough to be used in almost any setting, especially when used in conjunction with one of the replaceable coloured rims which give the product increased diversity in its interior design applications.
As well as reducing energy costs, there are other benefits too through the use of a light fitting such as the Lunar 2D wIth Microwave Sensor. Organisations and business could reduce their lighting maintenance costs, create a better workplace and show, in a really visible way, that their organisation cares about the environment.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
There are two main ways for sensors to detect when an area is occupied:
Microwave sensors transmit an inaudible microwave and monitor reflections from walls or objects in the room irrespective of heat or light. Line of sight issues do not affect microwave sensors as any movement of solid objects changes the pattern of the reflections and activates the sensor.
Key points:
• Activated by motion – speed and size not heat and light
• Unaffected by background temperature
• Completely enclosed within the lighting fixture as microwave operation can safely penetrate non-metallic objects such as glass and plastic
• Very stable performance which is suitable for any climate
• In line with the fittings IP rating, the units are dust and smoke proof as they are inside the fitting
• Very long life span of 100,000 hours plus
Passive infrared (PIR) sensors relate to the movement of objects by detecting their heat and light, but only in their field of view. As these products rely on line of sight their performance is affected when inanimate objects obstruct their field of view.
Key points:
• Activated by infrared – heat and light
• Do not function well in temperatures >35 degrees Celsius
• Cannot penetrate plastic or glass, so the detector has to be positioned externally to a light fitting, therefore they can become vulnerable to smoke and dust
• Lenses can age due to exposure to the atmosphere, which results in reduced performance over time
• Short life span of around 20,000 hours
The cutting edge microwave sensors used by Netlec.co.uk in a new generation of light fittings, such as the Lunar 2D wIth Microwave Sensor have numerous benefits:
• Purpose made for use in intelligent light fittings to suit energy saving applications
• Turn on when presence is detected, then dim down for a pre-set time to a lower percentage of brightness once the presence has passed
• The sensor is unobtrusive as it is located inside the light fitting, so there is no compromise to decoration or room design
• Extremely low transmission power equivalent to only 2% of that of a typical mobile phone
• Multi-operational settings which are variable to suit the user
• Wide operating temperature range of between -35 deg to +70 deg Celsius
• Replaceable rim trims with a range of colour options to suit the decor of the room
The Lunar 2D wIth Microwave Sensor is an Energy saving surface mounted flight fitting complete with a cutting edge integral microwave occupancy/light sensor. The fitting has been designed for Netlec.co.uk specifically to enhance their offering of energy saving products.
Fittings with microwave sensors are ideally suited to areas which only need to be illuminated when occupied and daylight diminishes below the required level. They are perfect for use in a wide variety of environments, where energy efficiency is of prime importance, for instance corridors, stairways, storage areas, toilets etc. Popular in schools and commercial premises, the Lunar 2D wIth Microwave Sensor is aesthetically pleasing enough to be used in almost any setting, especially when used in conjunction with one of the replaceable coloured rims which give the product increased diversity in its interior design applications.
As well as reducing energy costs, there are other benefits too through the use of a light fitting such as the Lunar 2D wIth Microwave Sensor. Organisations and business could reduce their lighting maintenance costs, create a better workplace and show, in a really visible way, that their organisation cares about the environment.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年3月9日星期三
Presence Detectors (PIR sensors and Microwave sensors)
Our wide range of PIR sensors and microwave presence
detectors are designed to reduce the amount of time lighting is left on
unnecessarily, for example if an area is unoccupied or if there is sufficient
natural light.
A presence detector monitors the detection zone for occupancy; if a person is sensed then the detector will automatically turn the lighting on. When the area is vacated, the lighting will turn off after a preset time delay. Most of our PIR sensors and microwave sensors have a built in light level (lux) sensor which will keep the lighting off if there is enough natural light available.
Controlling lighting with a presence detector can save up to 60% of lighting energy costs dependent on occupancy behaviour and the amount of natural light available; our PIR switches and microwave sensors can also be used to control heating and ventilation.
Detectors will switch on lighting automatically when a
person enters the room, and switches off lighting automatically when no
movement is detected.
Upon entering the room the person switches on the light as
normal, but on leaving the detector switches off the lighting automatically.
Lights can also be switched off manually.
A presence detector monitors the detection zone for occupancy; if a person is sensed then the detector will automatically turn the lighting on. When the area is vacated, the lighting will turn off after a preset time delay. Most of our PIR sensors and microwave sensors have a built in light level (lux) sensor which will keep the lighting off if there is enough natural light available.
Controlling lighting with a presence detector can save up to 60% of lighting energy costs dependent on occupancy behaviour and the amount of natural light available; our PIR switches and microwave sensors can also be used to control heating and ventilation.
Presence and Absence Detection Explained
The choice between presence and absence detection for different spaces can make a big difference in user-friendliness and the amount of energy saved.Presence Detection
Absence Detection
2016年2月24日星期三
Microwave sensors
Microwave sensors, also known as Radar, RF or Doppler sensors, detect
walking, running or crawling human targets in an outdoor environment.
Southwest Microwave developed the industry’s first bi-static microwave sensor in 1971, and has pioneered the development of flexible, reliable microwave links and transceivers for the protection of open areas, gates or entryways and rooftop or wall applications.
Microwave sensors generate an electromagnetic (RF) field between transmitter and receiver, creating an invisible volumetric detection zone. When an intruder enters the detection zone, changes to the field are registered and an alarm occurs.
Our microwave sensors are easy to install, provide high probability of detection, low nuisance alarms and resistance to rain, fog, wind, dust, falling snow and temperature extremes. Most operate at K-Band frequency, maximizing detection performance and minimizing interference from external radar sources.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
Southwest Microwave developed the industry’s first bi-static microwave sensor in 1971, and has pioneered the development of flexible, reliable microwave links and transceivers for the protection of open areas, gates or entryways and rooftop or wall applications.
Microwave sensors generate an electromagnetic (RF) field between transmitter and receiver, creating an invisible volumetric detection zone. When an intruder enters the detection zone, changes to the field are registered and an alarm occurs.
Our microwave sensors are easy to install, provide high probability of detection, low nuisance alarms and resistance to rain, fog, wind, dust, falling snow and temperature extremes. Most operate at K-Band frequency, maximizing detection performance and minimizing interference from external radar sources.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年2月3日星期三
Wireless heart-beat and breath-rate sensing by a microwave-sensor
With the availability of new microwave-based sensor from Sharp, you
don't need to physically-connect leads to the patients or put some
wearable medical electronics devices to read heartbeat and breath rate.
The new microwave sensor from Sharp DC6M4JN3000, can detect human and animal body motion and biological functions such as heartbeats and breathing from a distance of 3 M from the patient, without having any physical contact attached to the body of the patient. Another feature in these wireless RF sensor is, they can detect/sense with obstacles like mattresses, doors, and walls between the patient and the microwave sensor.
DC6M4JN3000 emits microwave radiation on human or animal subject, the reflected microwaves provides signals on heart rate and breathing rate of lungs. Basically the sensor module uses microwave satellite-television antenna technology, proprietary signal-processing circuit and an algorithm for detecting biological functions.
If you look at the accuracy, DC6M4JN3000 is capable of measuring heart rate within a margin of error of ±10% when placed roughly three meters away from the target subject.
Elderly-care or nursing-care is the target market for products built out of these sensors. These sensors will not work if there are metal like conducting obstruction between the patient and sensor, because microwaves do not pass through the metal layers.
Brief specs:
Directionality Azimuth: 25°, elevation: 20°
Power supply voltage 3.2 to 3.6 V
Power consumption Typ. 100 mA
Output frequency 24.05 to 24.25 GHz
Dimensions RF module (including antenna): 31.0 x 47.5 x 16.0 mm
Signal processing substrate: 30.0 x 46.5 x 5.0 mm
Operating temperature –20 to 50°C
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
The new microwave sensor from Sharp DC6M4JN3000, can detect human and animal body motion and biological functions such as heartbeats and breathing from a distance of 3 M from the patient, without having any physical contact attached to the body of the patient. Another feature in these wireless RF sensor is, they can detect/sense with obstacles like mattresses, doors, and walls between the patient and the microwave sensor.
DC6M4JN3000 emits microwave radiation on human or animal subject, the reflected microwaves provides signals on heart rate and breathing rate of lungs. Basically the sensor module uses microwave satellite-television antenna technology, proprietary signal-processing circuit and an algorithm for detecting biological functions.
If you look at the accuracy, DC6M4JN3000 is capable of measuring heart rate within a margin of error of ±10% when placed roughly three meters away from the target subject.
Elderly-care or nursing-care is the target market for products built out of these sensors. These sensors will not work if there are metal like conducting obstruction between the patient and sensor, because microwaves do not pass through the metal layers.
Brief specs:
Directionality Azimuth: 25°, elevation: 20°
Power supply voltage 3.2 to 3.6 V
Power consumption Typ. 100 mA
Output frequency 24.05 to 24.25 GHz
Dimensions RF module (including antenna): 31.0 x 47.5 x 16.0 mm
Signal processing substrate: 30.0 x 46.5 x 5.0 mm
Operating temperature –20 to 50°C
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年1月28日星期四
Portable microwave sensors for measuring vital signs
Current medical techniques for monitoring the heart rate and other
vital signs use electrodes attached to the body, which are impractical
for patients who want to move around. Plasma physicist Atsushi Mase, a
scientist at Kyushu University in Japan, and colleague Daisuke Nagae
have developed a new technique to disconnect people from their
electrodes by using microwaves.
The work, which could lead to the development of non-invasive, real-time stress sensing in a variety of environments, is described in a recent issue of the journal Review of Scientific Instruments, which is published by the American Institute of Physics.
The system uses very weak microwaves to irradiate -- and scatter off -- the human body. A sensitive microwave sensor monitors the reflected waves, which change in phase in response to motions of the body, including the regular displacement of the chest during breathing or, the slight movement of the chest caused by the beating heart.
"The skin surface moves slightly," Mase says, "synchronizing to respiration and heart beat."
Using signal processing algorithms and techniques to filter out the effects of random body motions, Mase and Nagae were able to detect changes in heart rate in near real-time, which allows an evaluation of autonomic nervous system activity.
"We plan to apply the system to various conditions, including for clinical use -- such as for the overnight monitoring of human vital signs -- and as a daily health monitor, including detecting signs of sleepiness in drivers and preventing stress-related illnesses," he says. In the future, the system could even be used as a security monitor to distinguish the subtle signs of stress in potential terrorists.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
The work, which could lead to the development of non-invasive, real-time stress sensing in a variety of environments, is described in a recent issue of the journal Review of Scientific Instruments, which is published by the American Institute of Physics.
The system uses very weak microwaves to irradiate -- and scatter off -- the human body. A sensitive microwave sensor monitors the reflected waves, which change in phase in response to motions of the body, including the regular displacement of the chest during breathing or, the slight movement of the chest caused by the beating heart.
"The skin surface moves slightly," Mase says, "synchronizing to respiration and heart beat."
Using signal processing algorithms and techniques to filter out the effects of random body motions, Mase and Nagae were able to detect changes in heart rate in near real-time, which allows an evaluation of autonomic nervous system activity.
"We plan to apply the system to various conditions, including for clinical use -- such as for the overnight monitoring of human vital signs -- and as a daily health monitor, including detecting signs of sleepiness in drivers and preventing stress-related illnesses," he says. In the future, the system could even be used as a security monitor to distinguish the subtle signs of stress in potential terrorists.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
2016年1月19日星期二
Microwave Sensors Auto-Detect Bikes At Intersections
In most cities, bike commuters lucky enough to have their own lanes
still cannot trigger traffic signals, forcing them either to wait for a
car to pull up, or cross the street to push the crosswalk button. A
microwave motion sensor can help by determining when bikes are present.
The Bay Area town of Pleasanton, Calif., is the only municipality in the nation to use this system, which cyclists say is already improving efficiency and safety. The Intersector motion and presence sensor can tell the difference between bikes and cars, and alter traffic signal patterns accordingly.
Many cities have embedded road sensors that can detect bikes as well as cars, but they don't work if the bike isn't positioned properly or if the bike is not made of metal. Bike commuters might be tempted to ride through the intersection rather than wait, which is neither legal nor safe.
Video-monitoring systems can also help detect bikes — Pleasanton uses these at all intersections — but they are stymied by wind and fog, according to the Contra Costa Times. Continuous video monitoring can also spark privacy concerns.
The microwave sensors can monitor up to eight detection zones, which the city would specify, and send up to four commands to the traffic signal control box — such as "right turn," "straight through" and so on. It updates 20 times per second and can track both moving and stationary vehicles, according to the manufacturer, MS Sedco. The systems cost between $4,000 and $5,000 apiece, the Contra Costa Times says.
Pleasanton has the systems at seven intersections so far, with plans to add at least one more. It should come in handy when cars are eventually outnumbered by bikes in that part of the country.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
The Bay Area town of Pleasanton, Calif., is the only municipality in the nation to use this system, which cyclists say is already improving efficiency and safety. The Intersector motion and presence sensor can tell the difference between bikes and cars, and alter traffic signal patterns accordingly.
Many cities have embedded road sensors that can detect bikes as well as cars, but they don't work if the bike isn't positioned properly or if the bike is not made of metal. Bike commuters might be tempted to ride through the intersection rather than wait, which is neither legal nor safe.
Video-monitoring systems can also help detect bikes — Pleasanton uses these at all intersections — but they are stymied by wind and fog, according to the Contra Costa Times. Continuous video monitoring can also spark privacy concerns.
The microwave sensors can monitor up to eight detection zones, which the city would specify, and send up to four commands to the traffic signal control box — such as "right turn," "straight through" and so on. It updates 20 times per second and can track both moving and stationary vehicles, according to the manufacturer, MS Sedco. The systems cost between $4,000 and $5,000 apiece, the Contra Costa Times says.
Pleasanton has the systems at seven intersections so far, with plans to add at least one more. It should come in handy when cars are eventually outnumbered by bikes in that part of the country.
iSweek（http://www.isweek.com/）- Industry sourcing & Wholesale industrial products
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