Borrowing technology it originally developed for power applications, Gowanda Electronics in Gowanda, N.Y., has designed an SMRF 2007 series of compact toroidal inductors to serve as signal filter components in radio frequency circuit designs. The inductors are incorporated into circuit boards by OEMs, among them Hewlett Packard and Agilent Technologies, for RF applications, including computers, computer peripherals, security systems, instrumentation, bar code devices, and laboratory analysis equipment.

Vertically mountable Gowanda toroidal inductors save circuit board space and minimize magnetic fields in radio frequency applications.

Like their power industry counterparts, the SMRF 2007s are equipped with a proprietary housing so the inductor can be mounted vertically, saving circuit board space. Mounted horizontally, as is common practice, the inductors would take up about half a square inch. Vertically mounted, they take up only a quarter-inch. The manufacturer says the compact package also minimizes external magnetic fields that can interfere with the electronics. The inductors' molded epoxy base provides heat resistance from -55°C to 125°C.

Gowanda specializes in developing magnetic components for the electronics industry, and customizes its new family of inductors to accommodate specific usage frequencies. This includes inductance ranging from 0.10 to 47 microhenries, current ratings from 575 to 3,100 milliamperes, and saturation current up to 4,500 milliamps. In production quantities, the inductors cost less than $1 apiece.

Extreme environments, such as vehicle, process control, or on-board flight testing, can damage sensitive pressure sensors. To deal with that problem, Validyne Engineering Corp. of Northridge, Calif., developed a differential pressure transmitter to perform accurately under extreme shock and vibration. The product, the P55 differential pressure transducer, uses variable reluctance sensing technology.

According to Martin Abbott, vice president of sales and marketing at Validyne, the variable reluctance technology is more robust than strain gauges, which use bridge circuitry of thin metal pieces that is subject to breakage. The P55 operates with a very thin metal diaphragm which, when exposed to differential pressures, moves in one direction or the other. The change in position of the diaphragm produces changes in a magnetic current, which correspond to the difference in pressure. While the P55 is subject to failure from significant over-pressurizing, its diaphragm can be replaced by removing four screws, Abbott said. The removable diaphragm also means that the P55 can be easily cleaned, he said.

The P55 differential pressure transducer uses variable reluctance to detect differences between pressures and to withstand shock and vibration.

Abbott said that the P55 could be configured for different pressure ranges by inserting a diaphragm of a different thickness. The company claims the sensor has a pressure measurement capability from 0.125 to 3,200 psi in 23 full-scale ranges.

Abbott claimed that the electrical signal has a high resolution that is sensitive to very small pressure changes. The P55 will accept both liquids and gases at the diaphragm. It operates in temperatures from -65°F to 250°F. The unit, which measures 1 1/2 x 1 1/2 x 4 1/2 inches, is contained in a NEMA 4 housing that resists spray and moisture.

When a robot on the factory floor hits something that it's not supposed to, the bump can result in downtime. A collision may damage the robot's end effectors, the often-delicate end-of-arm tooling, or harm surrounding machinery.

Typically, robots are equipped with breakaways—clutch sections in the arm that let it give like a broken wrist—to prevent damage. Another method of avoiding harm is to equip the robot with a power override sensor, which will cut power to the motors or hydraulics if it senses extra load on the arm. Yet each of these solutions has drawbacks. Breakaways can be heavy and can slow down the robot, and they do little to protect end effectors. Power override sensors often act too slowly to avoid damage.

The ATAM-4000R uses an accelerometer to provide crash protection to robots. The unit costs about $6,000 and can protect end-of-arm tooling.

ATAM Systems Inc. in Worthington, Ohio, says it has developed an alternative. The company, which supplies monitoring systems for CNC machines, offers the ATAM-4000R, which sends a trip signal to the robot controller within one millisecond of detecting a deviation. The quick reaction upon collision minimizes damage to tooling, fixtures, or process material, and limits crash-induced downtime and repairs.

Harry Kincaid, ATAM Systems' president, explained that the unit works by a small accelerometer on the robot's arm, which monitors movement in any direction. If the arm generates an abnormal signal by deviating from its pattern, the unit will send a signal to the robot's controller to take an appropriate action, which could be to shut off power, to retract to the home position, or to move to a neutral zone.

Kincaid said that the ATAM-4000R is extremely sensitive and quick, and can also filter out other noises and vibrations, decoupling it from movements of forklifts, for example.

Kincaid said that the ATAM-4000R can be interfaced with any CNC-based robot controller. It is equipped with a reset/relearn button that allows the sensor to learn new movements. The unit is also equipped with a modem that allows the company's tech support to troubleshoot the sensor from a remote location. Cost is roughly $6,000, said Kincaid, who added that a major automotive OEM is considering it for use.

As everyone who has been residing on the planet for the last few months must surely know, "It," the mysterious invention that was widely touted to change the world, was finally revealed as the Segway HT, a scooterlike device that will enable a rider to tool about the sidewalks, regulations permitting, at about 12 mph.

An array of sensors in the Segway determines the machine's precise orientation.

By all accounts, the most remarkable feature of Dean Kamen's invention is the array of sensors that can determine the precise orientation of the machine. Through massive computing power (there are 10 microprocessors aboard to interpret the data) this information is converted into instructions for the two small electric motors, one for each wheel. The resulting maneuvers are said to enable the Segway, and hence its rider, to remain upright despite all provocations, while interpreting the tiniest shifts of balance on the rider's part to take both machine and human in whatever direction is desired.

J. Douglas Field, chief engineer and vice president for product development for Segway LLC in Manchester, N.H., compares the sensors to those that enable humans to keep their balance—the inner ear and the eye, both of which are required to accomplish the task. The Segway's two tilt sensors, like the inner ear, use fluid to determine a level. The solid state gyroscopes, with their quick data refresh rate, can be compared to eyes.

The vehicle's five gyroscopes, which come from Silicon Sensing Systems of Plymouth, U.K., a joint venture of the British firm BAE Systems and Sumitomo of Japan, operate by vibration rather than spinning. The heart of the vibrating structure gyroscope is a tiny ring vibrating in a small box; the Coriolis effect is used to calculate the angular rate, according to Field.

Goodrich will be putting its name on more of the Trent engine. In what appears to be a first, Goodrich Corp.'s electronic systems unit will be the sole supplier of sensors for Rolls-Royce's Trent 900 turbofan.

Goodrich will provide a proprietary suite of more than 50 individual sensors to monitor temperature, pressure, speed, torque, and other critical engine performance data. Rolls-Royce said it has never done that before—that is, buy all of an engine's sensors from one source.

Meanwhile, Goodrich's aerostructures business has a separate contract to make fan case sections for the Trent.
The Trent 900 is being designed to power the Airbus A380 jumbo jet. Goodrich has also announced contracts to supply fuel systems, landing gear, and evacuation systems for the A380.

According to Rolls-Royce, the first Trent 900 engines to enter service will have thrust of 68,000 pounds, expandable to 84,000 lbs. The A380 will carry four of them.

The Trent 900 is one of two engines being developed for the Airbus A380. The other one is the GP 7200, the product of an alliance between General Electric Aircraft Engines and Pratt & Whitney.

Airbus Industrie, headquartered in Toulouse, France, is developing the A380 to compete against Boeing for the super jumbo jet market. The A380 will seat more than 500 passengers on two decks. It will have a maximum takeoff weight of 1.2 million pounds, or 560 metric tons.

Developers have scheduled the plane to make its first flight in 2004, and to enter into commercial service in 2006.

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