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The race to create tiny wireless sensors that could monitor anything from pressure in the eyes and brain to the stability of bridges appears to be heating up. Earlier this month, IEEE Spectrum reported on two approaches to creating an almost-indefinitely-running sensor using piezoelectric systems to convert tiny vibrations into power. Now, another team from the University of Michigan has created an alternative approach that uses solar power to keep the sensor running autonomously for many years.

25 March 2010—Nowadays, a phone that doesn’t know where it is or where it’s going can’t really call itself ”smart.” To orient themselves properly, smartphones require not just GPS capability but also an electronic compass, an accelerometer, and increasingly, digital gyroscopes. The point of a gyroscope is to sense any change in an object’s axis of rotation. Up until now, gyroscopes measured movement around the three axes with three sensors—one for pitch, one for yaw, and another for roll. At most, two of these sensors would be combined on a single die. The best you could do was, say, match up a 3- by 5- by 1-millimeter yaw sensor with a 4- by 5- by 1-mm sensor that would detect pitch and roll. But on 15 February, STMicroelectronics unveiled  a 4- by 4- by 1-mm gyroscope whose single sensing structure tracks all three angular motions. It’s a triumph of microelectromechanical systems (MEMS) engineering.

In earlier articles on intelligent sensor design, we saw how valuable they can be to both end users and those who manufacture and sell them. It’s now time to delve more deeply into what it takes to make intelligent sensors work.   The first step in that journey is to develop a solid, intuitive understanding of the principles of digital signal processing(DSP). Unlike many introductory DSP articles and texts, the focus here will be on presenting and using the important concepts rather than deriving them, for the simple reason that addressing the subject in depth is a book-sized, not a chapter-sized, project.

Earlier in this series, we touched on one problem that can arise when sampling an analog signal, namely the problem of aliasing. There are three other issues with signal sampling to which we now turn our attention: digitization effects, finite register length effects, and oversampling. So far, weve assumed that all of the signals were measuring are continuous analog values; i.e., our measurements are completely accurate. Even in the cases in which we have noise, the underlying assumption is that the measurement itself, for example the noisy sensor output voltage, is known precisely.

We’re all familiar with the general idea of a filter: it removes something that we don’t want from something we do want. Coffee filters that pass the liquid coffee but retain the grounds or air filters that pass clean air but trap the dust and other pollutants are two common examples of mechanical filters in everyday life. That same concept can be applied to noisy electrical signals to pass through the “true” signal of interest while blocking the undesirable noise signal. Looking at Figure 2.5c below, imagine for a moment that the signal of interest is in the lower-frequency region and that the noise signal is in the higher-frequency region. Ideally, we’d like to be able to get rid of that high-frequency noise, leaving just the signal component that we want.

With all of the new competition in the consumer robotics field, it’s about time for iRobot to show that they’re still capable of innovating new and exciting things. AVA, their technology demonstrator, definitely fits into the new and exciting category. AVA is short for ‘Avatar,’ although iRobot was careful not to call it a telepresence robot so as not to restrict perceptions of what it’s capable of. AVA is capable of fully autonomous navigation, relying on a Kinect-style depth sensing camera, laser rangefinders, inertial movement sensors, ultrasonic sensors, and (as a last resort) bump sensors. We got a run-down a few days ago at CES, check it out:

The potential for the QTC material to transition from an insulator to a conductor (i.e. change its electrical property) is influenced by how much deformation the material is experiencing as a result of the applied mechanical pressure. QTC can be used to produce low profile, low cost, pressure activated switches or sensors that display variable resistance with applied force and return to a quiescent state when the force is removed. The difference between a QTC switch and a QTC sensor is arguably only the speed and amount of physical input required to achieve the required switching point or resistance range.

In what comes as a bit of a surprise, Fuji Soft Inc.’s new humanoid robot platform for hobbyists and researchers has been given the name PALRO (pal + robot).  Naturally we feel this name is a superb choice!  Sales to research institutions will begin on March 15th, 2010 with a general release following later in the year.  The robot combines Fuji Soft’s software prowess with an open architecture which will give developers plenty of room to experiment. PALRO stands 39.8cm (15″) tall and weighs 1.9kg (3.5 lbs), and here’s the good news: it costs 298,000 JPY ($3300 USD).  Considering PALRO has 20 DOF, a camera, 4 directional microphones, a speaker, LED arrays in its head and chest, 4 pressure sensors in each foot, 3-axis gyro sensor, an accelerometer, and an Intel Atom 1.6GHz CPU, it is priced very competitively.  A comparative robot kit like Vstone’s Robovie-PC for example, costs $1100 USD more and doesn’t have such a fancy exoskeleton.

Just as photographic film was mostly replaced by silicon image chips, now quantum film threats to replace the conventional CMOS image sensors in digital cameras. Made from materials similar to conventional film—a polymer with embedded particles—instead of silver grains like photographic film the embedded particles are quantum dots. Quantum films can image scenes with more pixel resolution, according to their inventors, InVisage Inc., offering four-times better sensitivity for ultra-high resolution sensors that are cheaper to manufacture.

When the Arduino Duemilanove microcontroller appeared in 2005, it featured a set of female pin headers exposing most of the pins of the ATmega168 for easy hacking and for connecting accessory boards known as 'Shields'. The purpose of a shield is to provide new plug-and-play functionality to the host microcontroller, such as circuit prototyping, motion control, sensor integration, network and radio communication, or gaming interfaces, without worrying too much about the hardware implementation details. Seven years after the birth of the original Arduino, new shields keep coming out and are being cataloged on http://shieldlist.org/, a testament to the versatility of the design. It is also simple to build a DIY shield when nothing out there will meet your needs or when you want to understand how the shield concept works from the ground up.

bowl and pairing off to come up with a way to create and commercialise sensors and switches that generate their own power. The idea is that the parts will make external power sources redundant - because they can convert energy from body heat, light and vibrations straight into electricity. Self powered electronics have already sporadically been used in technology like wall-mount remote control units for air conditioners, says Nikkei, but existing parts are bulky and cost a couple thousand yen a piece. 3,000 yen is about $35 - which means they're not the best bet, financially, yet.

Single-walled carbon nanotube (SWCNT)-based thin film transistors (TFTs) could be at the core of next-generation flexible electronics – displays, electronic circuits, sensors, memory chips, and other applications that are transitioning from rigid substrates, such as silicon and glass, to flexible substrates. What's holding back commercial applications is that industrial-type manufacturing of large scale SWCNT-based nanoelectronic devices isn't practical yet because controlling the morphology of single-walled carbon nanotubes is still causing headaches for materials engineers.

Events such as natural disasters, military actions, and public safety threats have led to an increased need for robust robots — especially ones that can travel across complex terrain in any dimension. The ability to scale vertical building surfaces or other structures offers unique capabilities in military applications such as urban reconnaissance, sensor deployment, and setting up urban network nodes. SRI's novel clamping technology, called compliant electroadhesion, has enabled the first application of this technology to wall-climbing robots that can help with these situations.  As the name implies, electroadhesion is an electrically controllable adhesion technology. It involves inducing electrostatic charges on a wall substrate using a power supply connected to compliant pads situated on the moving robot. SRI has demonstrated robust clamping to common building materials including glass, wood, metal, concrete, etc. with clamping pressures in the range of 0.5 to 1.5 N per square cm of clamp (0.8 to 2.3 pounds per square inch). The technology works on conductive and non-conductive substrates, smooth or rough materials, and through dust and debris. Unlike conventional adhesives or dry adhesives, the electroadhesion can be modulated or turned off for mobility or cleaning. The technology uses a very small amount of power (on the order of 20 microwatts/Newton weight held) and shows the ability to repeatably clamp to wall substrates that are heavily covered in dust or other debris.

Not so long ago, artists routinely made their own paints using all sorts of odd ingredients: clay, linseed oil, ground-up insects—whatever worked. It was a crude and rather ad hoc process, but the results were used to create some of the greatest paintings in the world. Today I and other scientists are developing our own special paints. We’re not trying to compete with Vermeer or Gauguin, though. We hope to create masterpieces of a more technical nature: optoelectronic components that will make for better photovoltaic cells, imaging sensors, and optical communications equipment. And we’re not mixing and matching ingredients quite so haphazardly. Instead, we’re using our blossoming understanding of the world of nanomaterials to design the constituents of our paints at the molecular level.

Robots mean many things to many people, and National Instruments offers intuitive and productive design tools for everything from designing autonomous vehicles to teaching robotics design principals. The NI LabVIEW graphical programming language makes it easy to program complex robotics applications by providing a high level of abstraction for sensor communication, obstacle avoidance, path planning, kinematics, steering, and more.

On Monday, National Instruments announced one such platform. It's called LabView Robotics. In addition to LabView, the popular data-acquisition application, the package includes a bunch of tools specific to robotics. It can import codes in various formats (C, C++, Matlab, VHDL), offers a library of drivers for a wide variety of sensors and actuators, and has modules for implementation of real-time and embedded hardware. NI says engineers could use the package to both design and run their robotic systems. 

In 2008 a team of physicists from Argonne National Laboratory, in Illinois, and other institutions stumbled upon an odd phenomenon. They called it superinsulation, because in many ways it was the opposite of superconductivity. Now they’ve worked out the theory behind it, potentially opening the doors to better batteries, supersensitive sensors, and strange new circuits. Superconductors lose all resistance once they fall below a certain temperature. In superinsulators, on the other hand, the resistance to the flow of electricity becomes infinite at very low temperatures, preventing any flow of electric current.

In a recent video, Willow Garage researcher Eitan Marder-Eppstein describes the open-source navigation stack they've released as version 1.0. The code, available at http://ros.org/wiki/navigation, was designed to be flexible and cross-platform, he says, and could be used in anything from a small iRobot Create-based bot to a large multi-sensor robot like Willow's own PR2 (which Spectrum has covered in detail here and here).

Anyone can bake a cake, but while some chefs bake dry, uninspired bricks of dough, there are other chefs who make cakes we would die for. The ingredients may be the same, but the outcomes are so very different. This is also the case between average electronic products and world-class, market-changing products. One of the most recent technical sensations is the capacitive touch screen. But what makes some touch screen-based products amazing, while others get such poor reviews?