The new Maestro network-based multi-axis supervisor from Elmo Motion Control Inc. of Westford, Mass., is a good example of how much intelligence companies are now packing into their devices. Equally important, Maestro is designed to supervise Elmo's SimplIQ intelligent servos, creating a distributed architecture that shares the motion processing workload.

This architecture begins with Elmo's intelligent servo drives. These compact, high-power density units come with fully programmable built-in motion controllers, power supplies, and power amplifiers. With trade names like Harmonica, Cello, Bassoon, and Cornet, Elmo's drives play their own programs or take direction from the Maestro supervisor.

The new Maestro supervisor controls intelligent servos with a single wire over its CANopen bus.

Maestro links to the drives using a single wire over the CANopen bus. This simplifies the spaghetti of wiring that can crawl across a complex multi-axis machine, shaving it down to a few cost-saving cables. Maestro controls up to 126 axes and up to 16 axes of interpolated motion per CAN bus port. Its software enables users to develop applications and administer files. As a CANopen master, Maestro provides network management and clock synchronization. It also operates as an Ethernet-CAN gateway, giving users direct access to axis-level setup, monitoring, and analysis.

All this intelligence supports some very sophisticated applications. In a food process, for example, the system scans the size, shape, and weight of a chicken breast, then directs a series of waterjet cutters to slice it into equal portions.

"Maestro costs less than most controllers in the industry," said Elmo applications engineer Jack Curll. "Our intelligent drives would typically make a machine more expensive, but with Maestro the package is very competitive."

Imagine a solid-state motor, one that has no conventional moving parts and generates no magnetic fields. Running virtually silently, it can vary its speed from less than 1 micrometer to nearly 250 millimeters per second and achieve resolutions down to the nanometer level.

Nanomotion Inc. of Yokneam, Israel, has been making such motors for years, based on proprietary piezoelectric ceramic technology. Now prices have begun to fall to levels that make them adaptable to mass market products.

Wireless companies, for example, are testing piezo motors in cell phones with built-in camcorder zoom lenses. Unlike conventional motors, their silent operation does not drown out sounds entering the nearby microphone. Piezo motors could be used to build a truly silent pan-and-zoom security camera.

Ability of piezoelectric motors to achieve movement resolutions down to the nanometer level make them good for self-focusing microscopes.

Because piezoelectrics do not require or produce magnetic fields, piezo motors could control robotic surgical devices inside a magnetic resonance imaging machine. They could also position wafers during highly sensitive electron and ion-beam deposition in semiconductor manufacturing. The concept behind piezo motors is simple, even if the execution is complex, according to Alan Feinstein, president of the firm's U.S. subsidiary in Ronkonkoma, N.Y.

Instead of coils and magnets, the driver is a solid, single crystal of piezoelectric ceramic about the size of a stick of Trident gum. Piezo ceramics change their shape when excited by an electrical current.

Nanomotion divides the ceramic into four quadrants. It uses dual electrical signals to activate two diagonally opposing quadrants at a time. The currents cause the quadrants to stretch and bend, thus twisting the rectangle into an S.
This creates elliptical movement at the end of the ceramic, similar to the motion a hand makes when spinning a lazy susan. The only difference is speed: At the ceramic's resonant frequency of 39.6 kHz, it completes nearly 40,000 ellipses every second.

Piezoelectric motors rely on orbital movements to achieve linear motion at 250 mm per second.

Nanomotion packages the ceramic in a small housing with a spring that puts five pounds of force on the crystal. "As a result, we have static holding and braking without any power consumption," Feinstein said. "We can stop on a nanometer rather than a dime."

According to Feinstein, the motors are rated to run up to 20,000 hours. "After that, we service them to reestablish the preload compression of the spring and they're good to go," he said.

The typical motor produces about 10 newtons, or 1 pound force, of thrust. Nanomotion configures units with up to eight individual piezos. Users can control them with any standard servo controller. Typical applications range from driving linear and rotary stages to certifying disk drives and coating drug stents.

When you try to start your car and find the battery dead, there appears to be a better solution than just swearing and pulling out your hair. Called Battery Brain, it is a small device that connects to a car's battery.

Battery Brain uses advanced electronics and software to continuously monitor the charge strength of the battery. If the charge drops below a programmed level, Battery Brain automatically cuts off power to anything draining the battery, to extend the life of the charge.

"Battery Brain actually operates as an on/off switch between the battery and electrical system, preventing energy drainage of the battery due to electrical devices being left on, or due to an unknown short in the system," said Aharon Levinas, a mechanical and environmental engineer whose own frustration with dead batteries led him to develop the device and form a company, Smart Energy Solutions Inc., to market it. "It also protects electronic devices in the vehicle—such as DVD players or GPS systems—which can be damaged if the electrical current and voltage do not remain at a constant level."

The company, which is headquartered in Clifton, N.J., was formerly known as Datigen.com Inc.

Battery Brain can be used with any engine with a conventional lead-acid battery. Once installed, Battery Brain monitors the battery to ensure that it is maintaining a sufficient charge.

Should Battery Brain need to disconnect power due to excess drain, all it takes is a push on the device's reset control knob to start the engine—at which point the electric generator or alternator will recharge the battery. The Battery Brain III model comes with a remote control device to restart the battery, without having to lift the hood of the car.

The basic model has a suggested list price of $39.95. An advanced model with remote control and theft protection is $69.95.

Battery Brain is available through automotive accessories dealers nationwide. It may also be purchased online at www.batterybrain.com.

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© 2006 by The American Society of Mechanical Engineers