sensor Related Articles

Researchers at the University of Alabama at Birmingham have found a novel and practical way to combat malicious attacks on motion sensors inside mobile devices.In a study published in proceedings of the 9th Association for Computing Machinery Conference on Security & Privacy in Wireless and Mobile Networks, associate professor Nitesh Saxena, Ph.D., and Ph.D. students Prakash Shrestha and Manar Mohamed have created a way to defend mobile device users against motion-based touchstroke leakage with the injection of noise.Previous research shows that, much like the way a hacker can covertly capture inputs made from a regular computer keyboard, it is also possible to capture a user's inputs on a touchscreen. Currently, motion sensors on Android devices can be accessed by any application downloaded to the device, without a user's being prompted to give permission. By tricking a user into unknowingly downloading a malicious program, hackers could obtain sensitive information like passwords and PINs by tracking the vibrations made from the touchscreen and decoding the movements based on a keyboard's layout. Given the accuracy rate of this type of attack, mobile security experts consider it a significant threat to user privacy and are exploring methods to combat it."Most mobile platforms have established a sensor security access control model," Saxena said. "Android follows a model where read access to many sensitive sensors, like a phone's camera or microphone, is very restrictive or requires special permissions granted by the user. However, the read access to other sensors, like inertial sensors, is not restricted because Android may not consider these sensors explicitly sensitive. This openness in the Android sensor security architecture has given rise to potentially significant threat of motion-based side channel attacks."By utilizing a recently developed framework called SMASheD (Sniffing and Manipulating Android Sensor Data), initially created as a malicious application, the study's authors built a defense mechanism called Slogger that can be used to thwart sensor-based touchstroke logging attacks. As a user enters sensitive information, Slogger transparently inserts noisy sensor readings in order to obscure the original readings. Slogger works in the background of a device and is completely unnoticeable to a user and other trusted applications. It can be installed through the Android Debug Bridge, without the need to root the device or change its operating system.To test Slogger's effectiveness, the authors compromised an Android device using two of the latest touchstroke logging algorithms developed for touchstroke detection and inference. During this type of attack, the start and end points of a user's taps are monitored. With data recorded by the accelerometer, a hacker could determine whether a user is holding the device vertically or horizontally. They can also predict what areas of the screen were tapped by applying machine learning tools. Later, by mapping the predicted areas with the standard keyboard layout, a hacker can determine the series of taps.After installing the malicious application, the authors also installed Slogger. Upon being installed, Slogger prompts the user to do a series of typing tests, holding the device in various positions. This allows Slogger to learn the range of the sensor values based on the user's typing style. The user types while holding the phone in his or her hand and while it is lying on a flat surface. The values are later used to set the range of values for injecting noise during an attack."During the evaluation phase, we implemented Slogger in such a way that, whenever the user launches the application used for the attack, a noise inject request is sent to the Slogger server," Saxena said. "When the user closes the application, a request to stop Slogger is sent. The application can also be updated to send an inject request whenever the keyboard is running or whenever a user is entering sensitive information."Slogger searches for system files related to motion sensors such as an accelerometer or gyroscope, and injects noise until it receives a request to stop, like when the application being used for the malicious attack is closed. Without Slogger, the touchstroke detector had an 85 percent rate of accuracy. Once the Slogger application was enabled, the touchstroke detector was unable to detect any touchstrokes. During the touchstroke inference test, there was a 90 percent accuracy rate without Slogger. Slogger was able to reduce inference accuracy to 56 percent while the device lay on a flat surface. While the user held the device, inference accuracy was reduced by more than 20 percent.During the evaluation, the authors discovered Slogger was also highly effective in minimizing touchstroke leakage even when more than one motion sensor is leveraged by an attacker. 

Imec, the Belgian nanoelectronics research center, will present at this week's 'CMOS Image Sensors for High Performance Applications' workshop in Toulouse (France) a prototype of a high-performance, time-delay-integration (TDI) image sensor. The image sensor is based on imec's proprietary embedded charge-coupled device (CCD) in CMOS technology. Imec developed and fabricated the sensor for the French Space Agency, CNES, which plans to utilize the technology for space-based earth observation.  The prototype image sensor combines a light-sensitive, CCD-based TDI pixel array with peripheral CMOS readout electronics. By integrating CCD with CMOS technology, imec combined the best of both worlds. The CCD pixel structure delivers low-noise TDI performance in the charge domain, while CMOS technology enables low-power, on-chip integration of fast and complex circuitry readouts.A TDI imager is a linear device that utilizes a clever synchronization of the linear motion of the scene with multiple samplings of the same image, thereby increasing the signal to noise ratio. CCDs fit extremely well with the TDI application since they operate in the charge domain, enabling the movement of charges without creating excess noise. By combining the TDI pixels array with CMOS readout circuitry on the same die, imec produced a camera-on-a-chip or system-on-a-chip (SOC) imager, which reduces the overall system complexity and cost. The CMOS technology enables on-chip readout electronics, such as clock drivers and analog-to-digital convertors (ADCs), operating at higher speeds and lower power consumption not possible with traditional CCD technology.The prototypes were fabricated using imec's 130nm process with an additional CCD process module. An excellent charge transfer efficiency of 99.9987 % has been measured ensuring almost lossless transport of charges in the TDI array, and guaranteeing high image quality. Imec's specialty imaging platform combines custom design (i.e., specialized pixels, high-performance readout circuits and chip architectures) with optimized silicon processing, such as dedicated implants and backside thinning, to achieve high-end specialized imagers.  

At SPIE Photonics West, imec will present a new set of snapshot hyperspectral CMOS image sensors featuring spectral filter structures in a mosaic layout, processed per-pixel on 4x4 and 5x5 'Bayer-like' arrays.Imec's hyperspectral filter structures are processed at wafer-level on commercially available CMOS image sensor wafers, enabling extremely compact, low cost and mass-producible hyperspectral imaging solutions. This paves the way to multiple applications ranging from machine vision, medical imaging, precision agriculture to higher volume industries such as security, automotive and consumer electronic devices."Imec's latest achievements in hyperspectral imaging emphasize how our promising technology has become an industrially viable solution for a number of applications," said Andy Lambrechts, program manager at imec. "The new mosaic architecture, and extended spectral range, brings unique advantages compared to our previously announced hyperspectral linescan sensors for applications in which scanning would not be practical. It enables spectral imaging in a truly compact, tiny form-factor, that can even be scaled to handheld devices. From the technology standpoint, we have now successfully demonstrated linescan and tiled sensors, in which spectral filters cover many pixels, to mosaic sensors, in which filters vary from pixel to pixel. At the same time, the spectral range is extended and now covers down to 470nm."The newly developed mosaic sensors feature one spectral filter per pixel, arranged in mosaics of 4x4 (16 spectral bands) or 5x5 (25 spectral bands) deposited onto a full array of 2 Million pixels 5.5µm size CMOSIS CMV2000 sensor. Two versions of the mosaic hyperspectral image sensors have been developed:one 4x4 mosaic with 16 bands in the 470-630nm (visible range)one 5x5 mosaic with 25 bands in the 600-1000nm range (Visible – NIR range)"Imec's hyperspectral imaging sensors (100bands linescan, 32bands tiled and 16/25bands mosaic designs) are off-the-shelf, commercially available engineering sample sensors that we developed to address the fragmented machine vision market and to trigger interest for this unique technology from potential end-users in other industries," explained Jerome Baron, business development manager at imec. "We also offer customized spectral filtering solutions for companies that are already familiar with the technology and interested in developing proprietary solutions with a specific performance in terms of speed, compactness, spatial versus spectral resolution, bands selection, or cost."Related products:ANPVC5030ANPVC2260ANPVC1470ANPVC1210 

A small NO2 sensor featuring a low power consumption in the mW range has been developed by Imec and Holst Centre. The sensors have a low detection limit for NO2 (<10 ppb) and a fast response time. They are particularly well suited for air quality monitoring and serve as a solution to the increased demand for accurate local air quality monitoring for indoor and outdoor environments. The sensors are being tested in real-life situations, as part of an environmental monitoring platform.While wearable technology that measures body parameters has become increasingly popular in recent years, the Intuitive Internet of Things (I2oT) is next on the horizon: connecting everybody and everything everywhere with data stored in the cloud, turning the massive amount of data in information to make the right decisions, to take the right actions exactly as we need or want. The I2oT is expected to manage the sustainability, complexity and safety of our world. It will increase our comfort and wellbeing in many ways.Health issues resulting from poor air quality are a growing concern for consumers and accurate monitoring is becoming more and more in demand, for both outdoor and indoor environments.Air quality is typically measured on just a few distinct locations per city, with specialized equipment. Many current gas sensors are large in size, have high power consumption and are too cost prohibitive to be implemented on a large scale for I2oT applications. Imec and Holst Centre have developed small, simple, low power and high quality autonomous sensors that wirelessly communicate with the environment and the cloud.Imec and Holst Centre's NO2 sensors were integrated in the Aireas air quality network, a multiple sensor network in the city center of Eindhoven (the Netherlands). The purpose was to test -in actual outdoor conditions and long term- the stability of the sensors, and benchmark them against established reference sensors. The sensors are operational since early May 2015 and contribute with valuable outdoor sensor data since then. During traffic rush hours, the sensors detect a significant increase of NO2 concentration up to the health safety limits.Imec and Holst Centre are currently deploying a similar sensor network inside the Holst Centre building in Eindhoven to test the sensors for indoor air quality monitoring. This environmental monitoring platform today includes it proprietary NO2 sensor and commercial sensors for temperature, relative humidity and CO2. The measured levels can be monitored live, over the internet. In a next step, proprietary low-cost low-power sensors will be added for CO2, VOCs (Volatile Organic Compounds), ozone, and particle matter.The generated sensor data are transferred to the cloud, stored in a database and immediately available on (mobile) applications, explained Kathleen Philips, director of imec's perceptive systems for the intuitive internet of things R&D program. "Data fusion methodology and advanced algorithms enable us to combine data from different sensors such as temperature, several gasses, humidity, human presence detection and to derive contextual knowledge. This information contributes to a correct interpretation of the situation and helps us to take adequate actions to solve the problem. In this way, we have developed a context-aware intuitive sensing system."Companies interested in early application validation and development for distributed IoT networks and/or in the innovative technology and circuits to realize them are invited to become a partner in our R&D program. IP can also be licensed.

Imec and Holst Centre (set-up by imec and TNO) have demonstrated a prototype of a single-chip electrochemical sensor for simultaneous detection of multiple ions in fluids. The demonstrator paves the way to small-sized and low-cost detection systems for agriculture, healthcare and lifestyle applications, food quality monitoring and water management.Imec and Holst Centre's ion sensor solution is a generic platform that can be tailored towards specific applications. It enables efficient and low-cost monitoring, such as monitoring of nutrient concentrations in surface and waste water, both for agricultural applications and water quality. In the healthcare and lifestyle applications, it provides disposable point-of-care solutions, or conformable solutions for integration into patches. Depending on the application and the form factor, it can be mass produced through microfabrication or through screen-printing on inexpensive substrates such as glass or foil. As compared to commercial ion sensors, this bring a unique advantage in terms of low cost manufacturability, and size of the solution. Moreover, by changing the selective membranes on the electrodes, the sensor can be adopted to detect other ions.The presented prototype is a handheld device that integrates a single-chip sensor with different electrodes that detect pH levels in a range from 2 to 10 at a 0.1 pH accuracy. For the chemical elements chloride (Cl-), sodium (Na+), potassium (K+), and nitrate (NO3-) -ranging from 10-4 M to 1 M ions- the sensor detects at a 10 percent accuracy. Benchmarked against other available single-ion sensors, imec's prototype demonstrated comparable sensitivity and accuracy for a versatile multiple-ion solution."With small autonomous smart sensors that adapt to and wirelessly communicate with the environment and each other, imec aims to develop the building blocks that enable an Intuitive Internet of Things," stated Kathleen Phillips, program director perceptive systems at imec. "Our scientists and engineers have reached an important breakthrough demonstrating the capabilities of our technology with this versatile single-chip sensor. As we continue to improve our sensor platform, develop sensors for other ions, integrate more sensors into a single system, and extend the lifetime of our sensor, imec will be at the nucleus in driving the advancements of smart connected systems. We invite industry to join our R&D program, become a partner to jointly develop new ion sensing applications and to bring this technology to the market." 

Researchers are making an attempt to steer us closer to comfortable touch mechanisms for operating mobile devices. A promising sign that they are on to something is evident in iSkin. A team from Max Planck Institute for Informatics, Saarland University, Carnegie Mellon, CNRS LTCI, Telecom-ParisTech and Aalto University have authored a paper describing their work in "iSkin: Flexible, Stretchable and Visually Customizable On-Body Touch Sensors for Mobile Computing." They envision a digital life where one can use a comfortable, light wearable such as finger strap, arm sticker and even keyboard extensions on rollout paper attached to the wrist device for mobile touch input. A video shows iSkin in action. In one scene, it is an arm sticker to control a music player; the person presses various places on the sticker to play a song or adjust the volume. Another scene shows somebody using a finger overlay to accept an incoming call. The video also shows a keyboard extension that can be rolled out on demand for a smartwatch text entry. iSkin is flexible and stretchable; it can detect touch input with two levels of pressure, even when stretched by 30 percent or when bent with a radius of 0.5 cm, they said. It can be of different shapes and sizes for different parts of the body—-such as fingers, forearm, or ear. A key feature is its construction of biocompatible materials. That requirement was not taken lightly. The authors in the paper said "iSkin should be non-toxic, and easily cleanable, washable, or replaceable in order to limit the accumulation of pathogens such as bacteria. Moreover, the properties of skin vary greatly." As "wrinkliness, oiliness, and distribution of receptors, sweat glands, and hair follicles" vary across body locations and individuals, they said this presented a requirement for materials and adhesives compatible with natural skin and exhibiting a high variability of form factors. What they came up with is "based on advances in electronic skin (e-skin) and soft-matter electronics, an active research field in robotics and material science." The sensor can be thought of as a sandwich composed of multiple layers. They wrote that "iSkin is made of multiple layers of thin, flexible and stretchable silicone. The base material is polydimethylsiloxane (PDMS), an easy-to-process silicone-based organic polymer. PDMS is fully transparent, elastic, and a highly biocompatible material." A Reuters report by Matthew Stock on Monday had further comments on the materials and the research from co-developer Martin Weigel, who said the technology was initially coming from robotics :where it's used to give robots kind of a feeling similar to the human body, to human skin. However, we are the first to look into how we can use it on the body to control mobile devices; so as a kind of second-skin which nicely conforms to your body." Weigel said carbon particles inside the silicone make it conductive so they can use it for electronics. The Reuters report added that the stickers are attached to the body using a medical-grade adhesive, easily peeled off after use without hurting the skin. In their paper, they said that study results showed the sensor remained functional under typical and extreme deformations occurring on the human body; also it accurately sensed touch input when worn on various body locations. Right now there are no signs that you will find iSkin sensors in the marketplace; this is a proof of concept, said the authors, of on-skin touch sensing "that bears some promise over rigid sensors and computer vision based solutions." Related products: CY8CMBR2044-24LKXI