Goodbye to batteries and power sockets

Jun 03, 2008
Goodbye to batteries and power sockets
The demonstrator – a miniature conveyer system driven by compressed air – contains wireless sensors that provide their own power supply. © Festo

A broken cable or a soiled connector? If a machine in a factory goes on strike, it could be for any of a thousand reasons. Self-sufficient sensors that provide their own power supply will soon make these machines more robust.

When a factory machine breaks down, it’s hard to know what to do. Production often comes to a standstill until the error has finally been pinpointed – and that can take hours. The causes are legion; in many cases it is all due to a single interrupted contact.

Consequently, many manufacturers have long been hoping for a technology that will work without vulnerable power and data cables. The idea is basically feasible, using small devices that harvest energy from their surroundings and provide their own power supply rather like a solar calculator. Experts speak of energy self-sufficient sensor-actuator systems.

These high-tech components normally consist of a sensor, a processor and a radio module. They measure position, force or temperature and transmit the data instantaneously by radio. In this way, vital machine data reach the control center without using cables at all. Is the machine overheating? Is the drive shaft wearing out?

So far, however, there are hardly any off-the-shelf solutions with their own energy supply. Research scientists from the Fraunhofer Technology Development Group TEG in Stuttgart have now joined forces with industrial partners and universities in the EnAS project, sponsored by the Federal Ministry of Economics and Technology, to build a transportable demonstrator.

This is a miniature conveyer system driven by compressed air that transports small components in an endless cycle. The round workpieces are picked up by a vacuum gripper, transported a short way and set down on a small carrier, which conveys the parts back to the starting point. All steps of the process are monitored by sensors as usual.

The special feature of the demonstrator is that the sensing elements have no need of an external power supply. The machine uses photo diodes, for instance, to check whether the carrier has been correctly loaded – if so, the light from the diodes is obscured by the workpieces. Solar cells supply the energy for this workpiece detector. Another example are pressure sensors which monitor the work of the vacuum gripper. In this case, the power is supplied by piezoelectric flexural transducers.

The piezoelectric elements contain ceramics that generate electricity on being deformed. This deformation happens when the vacuum pump is switched on and off. The electricity thus generated is sufficient to send an OK signal to the central control unit. The sensor thus draws its power from pressurized air that is present anyway. Within the next two years, the various system components are expected to make their way into everyday industrial use.

Source: Fraunhofer-Gesellschaft

Explore further: New device could spell the end of no balls

Related Stories

Supercomputers a hidden power center of Silicon Valley

May 21, 2015

Silicon Valley is famed for spawning the desktop, mobile and cloud computing revolutions. What is less well known is that it's one of the nerve centers for building the world's fastest number-crunchers.

Gaza engineer seeks solution to water woes

May 12, 2015

With Gaza's supply of drinking water expected to dry up by 2020, a Palestinian engineer is pioneering a machine to make seawater potable for residents of the coastal territory.

WSJ: Google exploring new day for battery tech

Apr 13, 2015

When The Wall Street Journal turned out a story recently about how Google was exploring improved battery technology, technology watchers thought Google was not a minute too soon; in fact it was about time b ...

Recommended for you

Defusing bombs by color

May 22, 2015

This March, Cambodia held its first national-level science festival at the Royal University of Phnom Penh, attracting over 10,000 young students to the science booths over the course of three days. At one ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.