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In this video we present four types of wall climbing robots that were developed in Dr. Amir Shapiros lab at the Department of Mechanical Engineering of Ben Gurion University of the Negev, Israel. The robots shown are: First, a magnetic climber that has compliant magnetic wheels and is capable to climb on ferromagnetic surfaces. This robot can be used for inspection of ship hull or bridges. Second, is a Snail inspired wall climbing robot capable of climbing on non metallic surfaces using hot melt glue. The robot secretes the adhesive at the front and peels off the track from the wall at the bottom leaving a trail behind just like the snail does. Third, is a robot that uses sticky wheels in order to attach itself to the wall. It simply has 3Ms sticky tape on the wheels. It can climb on smooth surfaces like glass. Fourth, is a four legged wall climbing robot for climbing on rough surfaces. It has 12 claws made of fishing hooks mounted on each footpad, and it climbs like cat or other rodents. For further information email: ashapiro@bgu.ac.il. See also: www.bgu.ac.il/~ashapiro and http://bgurobots.pbworks.com/

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.

A new form of propulsion that could allow microrobots to explore human bodies has been discovered. The technique would be used to power robots and other devices such as microfluidic pumps from a distance. Finding a propulsion mechanism that works on the microscopic scale is one of the key challenges for developing microrobots. Another is to find a way to supply such a device with energy because there is so little room to carry on-board fuel or batteries. Now a team lead by Orlin Velev at North Carolina State University in Raleigh, US, has found that a simple electronic diode could overcome both these problems. Velev and Vesselin Paunov from the University of Hull, UK, floated a diode in a tank of salt water and zapped the set-up with an alternating electric field.

A new form of propulsion that could allow microrobots to explore human bodies has been discovered. The technique would be used to power robots and other devices such as microfluidic pumps from a distance. Finding a propulsion mechanism that works on the microscopic scale is one of the key challenges for developing microrobots. Another is to find a way to supply such a device with energy because there is so little room to carry on-board fuel or batteries. Now a team lead by Orlin Velev at North Carolina State University in Raleigh, US, has found that a simple electronic diode could overcome both these problems. Velev and Vesselin Paunov from the University of Hull, UK, floated a diode in a tank of salt water and zapped the set-up with an alternating electric field.

Given the maturity of MOSFETs, selecting one for your next design may seem deceptively simple. Engineers are familiar with the figures of merit on a MOSFET data sheet. Selecting a MOSFET requires the engineer to use their expertise in scrutinizing different specifications for individual applications. In an application such as a load switch in a server power supply, the switching aspects of a MOSFET matter little because the MOSFET is on almost 100% of the time. The on resistance (RDS(ON)) may be the key figure of merit in such an application. Still other applications, including switching power supplies, use MOSFETs as active switches, and cause the engineer to value other MOSFET performance parameters. Let us consider some applications and their prioritization of MOSFET specifications.

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.

The marriage of high performance optics with microfluidics could prove the perfect match for making lab-on-a-chip technologies more practical. Microfluidics, the ability to manipulate tiny volumes of liquid, is at the heart of many lab-on-a-chip devices. Such platforms can automatically mix and filter chemicals, making them ideal for disease detection and environmental sensing. The performance of these devices, however, is typically inferior to larger scale laboratory equipment. While lab-on-a-chip systems can deliver and manipulate millions of liquid drops, there is not an equally scalable and efficient way to detect the activity, such as biological reactions, within the drops.

Breadboarding a new circuit is a key skill and an important step in many projects—especially early on, when you need to move wires around and substitute components. But that very flexibility also makes it easy to knock wires out. Eventually, if your project is a keeper, you’re going to want something with a bit more permanence. Printed circuit boards (PCBs) solve all those shortcomings. But most people don’t even consider translating a one-off project into a PCB design. For one thing, PCB fabrication has traditionally been expensive, viable only in commercial quantities. (One alternative is to do it yourself with etches and silk screens, a messy and time-consuming process.) Also, there are technical constraints involved with PCB designs that are daunting to the casual hobbyist. But it turns out that nowadays you can produce a professional PCB very inexpensively.

Three-dimensional microchip designs are making their way to market to help pack more transistors on a chip as traditional scaling slows down. By stacking logic chips on top of one another other or combining logic chips with memory or RF with logic, chipmakers hope to sidestep Moore's Law, increasing the functionality of smartphones and other gadgets not by shrinking a chip's transistors but the distance between them. "There's a big demand for smaller packages in the consumer market, especially for the footprint of a mobile phone, or for improving the memory bandwidth of your GPU," says Pol Marchal, a principal scientist of 3-D integration at European microelectronics R&D center Imec. On 9 February, at the IEEE International Solid-State Circuits Conference (ISSCC), in San Francisco, Imec engineers presented some key design challenges facing 3-D chips made by stacking layers of silicon circuits using vertical copper interconnects called through-silicon vias (TSVs). These design constraints will have to be dealt with before TSVs can be widely used in advanced microchip architectures, Marchal says.

Today's FPGAs are doubling in capacity every 2 years and have already surpassed the 5 million equivalent ASIC gate mark. With designs of this magnitude, the need for fast flows has never been greater. At the same time, designers are seeking rapid feedback on their ASIC or FPGA designs by implementing quick prototypes or initial designs on FPGA-based boards. These prototypes or designs allow designers to start development, verification and debug of the design—in the context of system software and hardware—and also to fine tune algorithms in the design architecture. Quick and intuitive debug iterations to incorporate fixes are of great value. The ability to perform design updates that don't completely uproot all parts of the design that have already been verified is also a bonus! Whether the goal is aggressive performance or to get a working initial design or prototype on the board as quickly as possible, this paper provides information on traditional and new techniques that accelerate design and debug iterations.

March has seen two significant announcements from FPGA start-ups with innovative architectures: Tabula, with their time-domain-multiplexed architecture, and TierLogic, implementing their routing switches in a layer of thin-film transistors. Both approaches promise to significantly reduce the die size and cost of high-end FPGAs. But before these announcements broke, a relatively unnoticed paper at February's International Symposium on FPGAs described what may be the most radical technology of them all: FPGAs using electromechanical relays. No, this is not an early April Fool's joke, nor is it one of those "let's see if anyone will publish this one" academic exercises. The paper presented work by professors and students at the Stanford University departments of electrical engineering and computer science, and researchers at Altera Corp. The work was supported in part by DARPA funding.

Tiny semiconductor dots could lead to a new type of circuit based on magnetism rather than current flow. At least that’s the hope of researchers who’ve made the dots and are hoping to build them into a workable device. ”We want to make it into a so-called nonvolatile transistor,” says Kang Wang, head of the Device Research Laboratory at the University of California, Los Angeles. Such a ”spintronic” transistor would retain its logic state in the absence of current and require less power to switch a bit, reducing the electrical power required by a computer chip by as much as 99 percent. Wang’s research, supported in part by Intel, was published in March in the online version of Nature Materials. Where electronic transistors rely on the presence or absence of current to register the ones and zeros of digital logic, spintronic transistors depend on ”spin,” a quantum characteristic of the electron. Picture the electron as a rotating globe. When the north pole is pointing upward, that’s spin up; when pointing the other way, it’s spin down. When the spins of most electrons are aligned, the material is magnetic. When their spins are random, the material isn’t. An applied current can align or randomize the spins, allowing for spin-based switches.