The Kynix Blog

A team of MIT engineers has described a novel way of controlling the flow of water in flexible tubes, a finding with implications for agricultural systems worldwide. Their research, published in the Journal of Mechanical Design, could reduce the energy demands of pulsating sprinklers used for irrigation."Food and its relationship to water is one of the biggest problems in the world," says Ruo-Qian Wang, a former postdoc at the MIT Tata Center for Technology and Design who is now a postdoc at the University of California at Berkeley. "There is a clear need for efficient irrigation technologies that save money and conserve resources."Wang co-authored the paper with three researchers in MIT's Department of Mechanical Engineering: graduate student Teresa Lin, PhD candidate and Tata Fellow Pulkit Shamshery, and Assistant Professor Amos Winter.The model they propose could be especially useful in developing countries, where many farmers cultivate small plots of land without reliable access to the electricity grid. These farmers rely on solar or diesel power to draw water for irrigation."If you bring down the energy requirements of the irrigation system, that means a farmer can buy a smaller solar panel, or use less diesel," Wang says. "Everything gets cheaper and more accessible."Compensating for pressureThe researchers focused on a device called a Starling resistor, which is a flexible tube that collapses as pressure is applied. This device is noted for its similarities to human respiration, and has been used to model flow in the lungs and airways."But," Wang says, "it has never been applied to a pressure-compensated flow control system for agriculture."The team created an experimental Starling resistor architecture that introduces a needle valve, which allows for independent control of two key variables: activation pressure and flow rate. The goal is a phenomenon called pressure compensation, in which a steady flow rate can be maintained no matter the pressure differential."Activation pressure is key to energy consumption," Wang says. "A traditional resistor has to achieve a high level of activation pressure, about 1 bar, to activate the pressure compensation mechanism. That takes a lot of pumping power."The team's experiment showed that using a rubber tube to replace the diaphragm of the existing Starling resistor design can reduce the needed activation pressure by 90 percent."As a result, Wang says, "farmers can use smaller pumps and smaller solar panels to provide the activation pressure."They placed the needle valve at a critical juncture in the system, where, together with the rubber tube, it acted as part of a series of resistors to water flow. Using different tube lengths and thicknesses, they discovered that adjusting the needle valve changed the flow rate, but did not change the minimum pressure needed to "activate" the system. Their paper describes the first mathematical model that quantitatively predicts this decoupling of the two variables.This means their device could make it easier to optimize irrigation systems for a variety of settings."We can design the activation pressure using a given tube material and geometry, and by adjusting the needle valve, water can be applied to different crops at different flow rates," Wang says.This new Starling resistor can be optimized for a high flow rate—necessary for pulsating sprinklers—while the pressure compensation phenomenon also causes the tube to oscillate, which gives it a natural pulsating quality.Wang explains that "a traditional sprinkler uses a spring-loaded arm to impact the flow rate. That wastes energy, and energy has a cost. This device provides pulsation by itself."Leveraging global expertiseThe project has grown out of the team's partnership with Jain Irrigation Systems, a multinational company headquartered in Jalgaon, India, that provided funding, technical knowledge, and market expertise. Researchers in Winter's GEAR Lab have collaborated with Jain on a number of projects related to water and agriculture."Jain is a $1 billion revenue company with small-scale farmers comprising 80-90 percent of their clients," says Wang. "They can commercialize agriculture projects in that space better than any other company."He notes that Jain's guidance and ability to field-test prototypes helped keep the Starling resistor project on the right track."Being able to test this architecture with Jain helped us determine that it had potential in sprinkler systems. Now we have a great opportunity for our work to make an impact."Reference:KY83-TFH85M51R0JEKY83-PF2472-100RF1KY83-P8212 

Induction cooking appliances commonly make use of resonant topologies which allow bidirectional current flow. Additionally they demand a discrete IGBT that performs best at switching frequencies from 18 to 40kHz and has low losses. Infineon has launched a family of discrete IGBTs to address these needs. The RC-E devices are cost optimised and specifically meet the demands of low- to mid-price range induction cookers and induction rice cookers.Monolithically integrated reverse conduction diodeThe RC-E family features an IGBT with monolithically integrated reverse conduction diode for resonant switching. The technology used in RC-E IGBTs is also optimised for low switching and conduction losses. Lower losses allow designers to achieve efficiency and power targets for induction cooking applications more easily. Thus, less energy is consumed for cooking, leading to lower operating costs for consumers. With low E off, V F, R th and V ce(sat) this device sets a new industry benchmark in price/performance and ease-of-use.The new devices offer Infineon’s proven quality in discrete RC IGBTs and fulfill all the requirements for soft switching applications and efficiency as well as EMI standards. The RC-E delivers the well-established high-performance of its predecessors with a more attractive price for lower BoM cost. The RC-E is offered in a standard TO-247 package allowing a drop-in replacement for existing designs.Samples are available now and the devices are in production. The family will be launched with two devices: 15 A and 25 A, both with the most commonly used blocking voltage of 1200V.Reference:KY56-MN3306KY0-SE40PJ-M3/86A

TT Electronics launched the LCS series of thin film resistors. For sensing and measurement of DC and AC currents in the sub-3A range, the resistors bring precision thin film resistor performance into the field of low ohmic values for use in very accurate current sensing applications. Most thin film chips have a minimum value in the range of one to 10Ω, but TT Electronics’ LCS series uses a proprietary technology to extend this down to 100mΩ.The resistors also feature low sensitivity to temperature variations.Aimed at designers of power supplies, battery monitoring, process control and point of load converters, the LCS resistors will find acceptance for use in market sectors such as industrial, medical, instrumentation and IT.The resistors offer a level of precision of ±0.5% and ±50ppm/°C, providing higher precision and temperature stability of current measurement. While there are currently a few thin film chip products below one ohm that use the nickel phosphorus material traditionally used for low value films, TT Electronics’ proprietary LCS film system delivers lower TCRs (temperature coefficient of resistance) in the hundreds of milliohms range.Available in five sizes from 0603 to 2512, LCS resistors feature high power ratings, e.g. 1W for 2512, which is comparable to thick film ratings. This also enables smaller footprints to be used. Enhancing reliability and reducing field failures in industrial applications, LCS also feature anti-sulphur terminations.A major factor driving the demand for this type of product is the growth of battery powered equipment. The proprietary thin film technology of TT Electronics’ LCS bridges the gap between the ohmic values offered by bulk metal chips and those of conventional nichrome thin film chips. Whilst thick film chips are also available in this very low ohmic range, LCS offers superior precision, offering the lowest TCR for precision current sensing available in the 0.1 to 1 Ω range.Reference:KY83-ERA-S15J180VKY83-ERA-S15J472VKY83-ERA-S27J182V 

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 

A new kind of wearable. It doesn’t track your steps, or how many calories you’ve burned in a day. Nor does it analyse your sleep cycles and record your workouts. This wearable analyses something else, your posture. The UpRight is a posture trainer that does not only read your posture when sitting, but also rectifies it by providing real time biofeedback.Your back posture has a knock-on effect across your bodily functions, and when your posture is poor, this has negative repercussions from decreased lung capacity, increased blood pressure, decreased digestive function, back pain and decreased bone density.The UpRight sensor affixes to the user’s back via single-use adhesives and vibrates when it senses the user has slacked from a good postural position, to remind them to adjust accordingly.The vibration and sensitivity levels can be manually adjusted on the UpRight app, allowing the user the choose how strict they want their posture training to be.The app has tutorials on correct posture and how to use the UpRight vibration sensorproperly, as well as an easy to understand infographic displaying the user’s training progress and history.The UpRight sensor can be worn for a length of time at the user’s discretion, but UpRight suggest wearing it for 15 minutes to an hour every day. The Upright training programmes to gradually train core muscles and build muscle memory.“UpRight’s training is built on Skinner’s theory of operant conditioning negative reinforcement, which explains that a behaviour is strengthened by removing an aversive stimulus. In UpRight’s case, the vibration is the aversive stimulus. Skinner’s theory explains why UpRight’s training is almost entirely subconscious and trains you to naturally improve your posture gradually,” UpRight explain.The UpRight blog regularly updates with information on the benefits of good posture, not only physical, but also psychological. Read the ‘5 reasons to start working on your posture, and one way to do it’ blog here.Reference:KY45- D7E-1KY45-BU-27135-000KY45-1005940-1