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Train delays due to leaves on the line could be a thing of the past if a prototype developed at the University of Birmingham is adopted by railway networks.Every year, thousands of commuters endure the frustration of Autumn delays caused by the accumulation of leafy slush on train tracks – and these problems usually reach their peak in mid-November, when leaf loss is coupled with high levels of moisture in the air or on the ground.Lee Chapman, Professor of Climate Resilience from the University, was inspired by the Internet of Things, which uses a range of innovative power, communication and sensing technology to aggregate real-time, on the ground, data.Funded by EPSRC and the Rail Safety and Standards Board, he worked with Alta Innovations, the University of Birmingham's technology transfer company, to transform the concept into a reality. His new technology, called AutumnSense, uses low-cost sensors to continuously measure the level of moisture on the railway line at potentially thousands of sites across the network. By linking this data with a leaf-fall forecast, operators can identify where and when the risk is greatest. This allows the precise and efficient use of automated treatment trains, which can clear the lines before the morning rush hour starts. His team are now testing the next element of the solution which is a low-cost method to count the number of leaves remaining on the trees.Professor Chapman's team had previously developed low-cost devices that are fitted to lamp-posts, and transmit data on road surface temperatures, to show precisely where road gritting is needed, and where it isn't. The road technology, called WinterSense, is currently being tested by commercial partners and is expected to be in mass production by the end of this winter.Professor Chapman said, "One of the major issues with road and rail safety is that hazardous conditions are usually highly localised. For remedial actions to be efficient, and demonstrate 'best value' for the taxpayer, resources should be deployed where they are needed, rather than in a blanket fashion."He is marketing AutumnSense and WinterSense through AltaSense, an operating division of Alta Innovations, and hopes to incorporate by Autumn 2017.He said, "Even though leaf loss and damp conditions can largely be predicted - and despite automated treatment trains working round the clock from October to December - a windy, rainy night still causes havoc for commuters. We have run an initial trial of AutumnSense on a stretch of London Underground tracks that are above ground, and are hoping to move quickly towards a fuller network wide trial."Wet leaves pose a very real safety challenge for train operators, potentially doubling the breaking distance and causing signalling issues, or 'disappearing trains' on the rail control systems due to the electrically insulating effect of the leaves which can prevent operation of track circuits. Leaves on the line are only an issue when they are mixed with moisture or dew, creating a slippery, Teflon-like substance. Reference:KY45-D7E-1KY45-BU-27135-000KY45-1005447-1 

An ultra-compact implantable image sensor using body channel communication has been demonstrated in Japan. The body channel approach allows the sensor-transmitter device to be much smaller and use less power than an RF wireless unit.  Fundamental limitsInterest in implantable medical sensors is on the rise as developments in established technologies and new concepts are making more and more applications feasible. One thing that all such sensors share is the need to be able to get the information they gather within the body, out of the body.RF communication is widely used for such applications, however, with implantable devices size reduction is generally desirable to reduce invasiveness, and in some applications there are also specific size limitations, owing to where and how the sensors are to be implanted. For example, sensors intended for use inside the brain need to be very compact.Using smaller antennas generally means using higher frequencies, and that in turn leads to attenuation problems with biological tissues. To compensate for increased attenuation more power is needed, which is also a serious issue for an implantable device.Conductive communicationAn alternative wireless approach to sending the data is body channel communication, in which an electrical signal is transmitted by conduction through the tissues of the body. In this issue of Electronics Letters, researchers from the Nara Institute of Science and Technology's Graduate School of Materials Science report using this approach to transmit and receive image data from a CMOS sensor fully implanted in a simulated body environment.Their sensor design, using body channel as the transmission method, will allow data to be read from the device by attaching an electrode to the surface of the body near the implantation site, as well as allowing the sensor unit itself to be low-power and small."Our implantable CMOS image sensor is intended for biomedical applications such as brain functional imaging," explains team member Hajime Hayami. "It can be planted with minimum invasiveness. Its features enable implantation of a number of sensors in a brain to investigate collaborative neural activities."In their experiments, the team at Nara have transmitted images from a CMOS sensor submerged in phosphate buffer saline (PBS), a body simulant material, to a receiver electrode 2 mm away. The experiments prove the principle of operation for this form of communication and even this small distance is enough to allow in vivo use in smaller animals."We are planning to apply our device to brain functional imaging of a mouse brain in the near future. Because the size of a mouse brain is only a few mm thick, the transmission distance of 2 mm is sufficient. Even in the case of signal transmission through a longer distance with a larger animal, the experimental results indicate that this method can be applied by adjusting the sensitivity of the receiver circuit," said Hayami.Neural arraysBefore the team can proceed with implantation in an animal, they need to integrate all of their PCB based devices into a single chip. This chip has already been designed and they are now working on the fabrication, with the goal of beginning implantation experiments by the end of 2014.Meanwhile, the Nara researchers have also been working to develop the design and say that relatively long distance transmission is now possible through improvements to the receiver circuit. On the sensor/transmitter side, they have also shown that they can use pulse-width modulation rather than an ADC output from the image sensor.The central goal of their work is creating tools for research into the human brain. "Our research group aims to elucidate the cooperative neural activity with distributed ultra-small sensors in the brain. We think we can achieve the goal by designing more intelligent chips based on the proposed communication method," said Hayami.The team believe that current sociological trends, including aging societies, will continue to drive demand for implantable devices, and that the applications of this kind of technology may develop to include more natural interaction between users and technology. Hayami commented that "I hope we will create an epoch where one can unconsciously use implantable devices by developing a brain-machine interface."Reference:KY45-OVM7695-RAEAKY45- OV09726-A40A-1DKY45- MT9P001I12STC 

The Internet of Things (IoT) describes devices and applications that gather and distribute data for everyday life. Sensor devices and processes that will underpin the IoT need to be small, versatile and energy efficient. Now A*STAR researchers have developed a sensor processor node that is capable of intelligent sensing while using ultra-low levels of power.IoT applications range from biomedical signal processing to uses in vehicle-status monitoring and environmental sensing. Most IoT devices are tiny in size, which means that they typically consume only a small amount of power. This is particularly challenging for processors that sample the information from sensors and analyze the data, as their power demands, in contrast, are intense, explains Xin Liu and Jun Zhou from the research team. "The limits on the space for power sources such as batteries leads to a critical power budget at the level of the micro Watt," says Liu. "At this level, processor design becomes extremely challenging if we are to achieve ultra-low power consumption whilst maintaining comprehensive functions."Typically, the lower the operating voltage, the lower is the overall power consumption. The Institute of Microelectronics research team adopted ultra-low voltage circuitry and system design techniques, and further developed diverse hardware accelerators for high-energy efficient signal processing of sensor information.A further key advance is possible by taking a more intelligent approach to the signal acquisition, by utilizing the knowledge about the specific sensor signals. In many applications, sensor signals take the form of sudden spikes, which are best-processed using cognitive sampling technologies. The advantage of those techniques is that they reduce the amount of data that needs to be processed by about 40 per cent which greatly reduces the power consumption.Using such techniques, the researchers were able to develop a sensor node processor design that can operate on ultra-low operating voltages as low as 0.5 volts, and that use only 29 to 39 pico Joule per operation cycle.The design represents a step toward a more comprehensive set of hardware systems, explains Liu."Emerging IoT devices play a key role to support the Singapore Smart Nation initiative in a wide range of applications," says Liu. "Our research team aims to develop high energy efficiency hardware circuits and systems, to achieve high performance, artificial intelligence, high energy efficiency, and a high security level."Reference:KY45-D7E-1KY45-BU-27135-000KY45-1005447-1  

The Telecontrolli capacitive rain sensor detects precipitation rate, current precipitation intensity and its end with precision and effectiveness, avoiding false positives which can cause inappropriate operations (objects such as dirt or other particles that in preexisting optical sensors cause a reflection mimicking the one of rain and limit its effectiveness in rapidly responding to light rain).Capacitive sensing is a technology based on the change in capacity determined by the change of the dielectric constant of the material separating the electrical conductors (plates) of the capacitor following the action of external agents.Capacitive sensing is becoming a popular technology to replace optical detection methods and mechanical designs for applications like proximity/gesture detection, material analysis and rain/humidity detection, because it offers more reliable and accurate measurements than optical ones.The sensor has IDT electrodes on one side of the alumina substrate, while a resistive heater and a temperature sensor are placed on the opposite side. The rain sensitive area, which in dry conditions assumes the nominal value of 100pF. Moreover in presence of the rain, the capacitance goes to high values compared to dry conditions and the ratio changing is over 300%.The integral and configurable heater is provided to ensure that the detection surface dries quickly, protecting the surface from fog, condensed moisture and frost. It also can be disabled when power consumption is critical.The alumina substrate and the glass sensitive layer makes the sensor immune to water and moisture absorption, ensuring high resistance and long duration.Moreover, thanks to the thermal conductivity of the ceramic, the heat emitted by the heater on the back of the sensor is immediately transferred to the upper surface, making the sensor more sensitive than other technologies.Furthermore, while resistive rain sensors are sensible to corrosion and contamination, the Telecontrolli capacitive rain sensor doesn't suffer from these disadvantages, making it suitable for any type of application - including irrigation systems for agriculture, automotive wiper systems, weather stations, and applications for home and building automation.  

Housed in a compact 2.5x3.0x0.95mm3 package, the BMX160 has been announced by Bosch Sensortec as the world’s smallest 9-axis motion sensor. The device is suited for space- and power-constrained applications such as smartphones, smart watches, fitness trackers, smart jewelry (e.g. rings, necklaces) as well as AR/VR devices.By combining Bosch Sensortec’s advanced accelerometer, gyroscope and geomagnetic sensor technologies, the BMX160 is able to meet the increasingly more stringent low-power requirements demanded by wearable devices. Bosch's low-power sensor technology makes this the standout 9­-axis inertial sensor on the market, reducing power consumption below 1.5mA.Jeanne Forget, Vice President Marketing, Bosch Sensortec, commented: “By combining Bosch Sensortec’s advanced sensor technologies into a single compact package, the BMX160 sets new industry benchmarks for high performance, tiny footprint and low power consumption. This device finally overcomes today’s placement constraints in smartphones and directly addresses the demands of wearable devices, where PCB space and low power consumption are at an even greater premium.”Enabling wearable applicationsThe BMX160 sensor enables Android wearable applications relying on sensor data such as device orientation, magnetic heading or the gravity vector. Moreover, the sensor supports applications such as 3D indoor mapping and smartphone optimised VR applications (e.g. cardboard VR). The sensor can be used in conjunction with the Bosch Sensortec BSX sensor data fusion software library to further optimise performance.The single-package BMX160 effectively replaces the present mainstream two-component workaround solution, i.e. combination of a 6-axis IMU with a 3-axis geomagnetic sensor. This innovative 9-axis motion sensor provides the placement flexibility necessary for overcoming current limitations on positioning of the magnetic sensor. Pin- and register-compatibility with Bosch Sensortec’s industry-standard 6-axis BMI160 IMU simplifies the task of upgrading designs.Built-in power management unitThe BMX160 has a built-in power management unit and ultra-low power background application features. This enables the power-hungry application processor to remain in sleep mode much longer, for example when counting steps, which further contributes to extending battery recharge intervals. The integrated step counter function and the Android compatible significant motion detector only consume 30µA each.The accelerometer, gyroscope and magnetic technology in the BMX160 have been optimised for low offset, low noise and best temperature stability. Bosch Sensortec gyroscope technology offers an extremely low drift, which is a key requirement for an accurate real-time user experience, especially in AR & VR applications.Reference:KY45-EKMB1203111KY45-AMN41122KY45-EKMB1101112

The piezo actuator with haptic feedback and integrated sensor functionality has been presented by TDK Corporation at this year’s electronica. The new actuator features unrivalled performance in terms of acceleration, force and response time, and offers an unprecedented quality of haptic feedback. The compact and powerful actuator enhances the sensory experience of HMIs significantly by engaging the full range of human tactile sensitivity.Driven by the miniaturisation of devices and applications and the requirements for more ease of use, multifunctional touchscreens and touch surfaces have become nearly ubiquitous. While these human-machine interfaces (HMI) do feature many advantages, there is one important drawback: the haptic feedback to user actions is very limited and not strong enough.As a result of this such HMIs are often less user-friendly and prone to errors. They can sometimes be s safety risk.The new actuator is based multilayer piezo plates with cost-effective copper inner electrodes. Thanks to the multilayer technology the actuators can be driven with relatively low operating voltages up to 120V.When activated, the piezo plates only expand minimally in the z axis, but due to the constant volume of the piezo effect contract simultaneously in both the x and y axes. The new component employs cymbals on both sides of the plate as levers to amplify the contraction by a factor of 15 in the z axis. The actuator is initially available in two types, a 5N type that achieves a displacement of up to 100µm and a 20N type that can achieve a displacement of more than 200µm. Despite their compact dimensions of 12.7x12.7x1.6mm and 26x26x2.4mm, respectively, the new actuators can generate forces of up to 5N and 20N.Compared with conventional electromagnetic solutions such as eccentric rotary motors (ERMs) and linear resonant actuators (LRAs), the piezo actuator with haptic feedback features the highest acceleration and force, the lowest insertion height and the fastest response time, all in a single component with integrated sensor functionality: Under a load of 0.1kg, the 5N type delivers an acceleration of 5.0g with a rise time of 2ms while the 20N type features 15.0g after just 1ms.Unlike conventional electromagnetic solutions the piezo actuator with haptic feedback can excite the entire stimulation range between 1-1000Hz. They have no significant frequency or amplitude limitations for customized haptic feedback to key human mechanoreceptors. In this way, the new actuator enables designers to custom develop high-definition haptic feedback profiles that users expect from cutting-edge HMIs. Applications for the piezo actuator with haptic feedback can be found, for example, in vehicles, smartphones and tablets, household appliances, ATMs and vending machines, game controllers, industrial equipment and medical devices. Main applicationsVehicles, smartphones and tablets, household appliances, ATMs and vending machines, game controllers, industrial equipment and medical devices.Main features and benefitsVery large forces of 5N and 20N, respectivelyLarge displacement of 100µm and 200µm, respectivelyExtremely low insertion height of 1.6mm and 2.4mm, respectively Reference:KY45-EKMB1203111KY45-AMN41122KY45-AMN14112