The expected boom in demand for small, often isolated devices in the Internet of Things is driving developers to craft new types of components.
Two developments announced this week should help IoT come together. On Wednesday at a trade show in Tokyo, researchers showed off a prototype of a tiny power supply that harvests energy from vibrations in the air so remote sensors and other parts don’t need batteries. And on Thursday, U.K. chip company Imagination Technologies announced a design for radio chips that can be used in small, power-sipping devices.
IoT promises to feed data from machines and sensors everywhere to systems that can deliver reports or automatically make changes in public or private infrastructure. To do that, the emerging network has to get into places that wires, cables and support teams can’t easily reach, especially if those remote devices number in the millions. That makes size and power requirements stricter than ever.
One emerging technology to power standalone devices in the field is vibration harvesting, or generating electricity from movements in the environment. It can use a variety of sources, including wind, water, radio waves and human movement. For example, the motion of a person walking might help to power a small wearable device.
At the Techno-Frontier conference in Tokyo, researchers from Europe and Japan are showing off a prototype built around an electrostatic vibration harvester from Japanese automation vendor Omron with power management electronics from European research institution Holst Centre/imec. Combining the two technologies allowed them to build a vibration-based power supply that’s much smaller than current models, the partners said. The DC power module they built measures 5 centimeters by 6 centimeters and may be able to shrink down to just 2 square centimeters.
The prototype is going through testing and customer input before volume production. It could be substituted for batteries in current designs or used in totally new products, the partners said.
The power supply is intended for wireless sensors for industrial applications such as equipment control and predictive maintenance. The sensors themselves could be “set and forget” devices with little need for maintenance because they wouldn’t need replacement batteries. The researchers’ design could be tuned for power output between 1.5 volts and 5 volts, the partners said.
Like Omron and Holst, chip architecture vendor Imagination is addressing small, wirelessly connected things. Its Ensigma Series4 “Whisper” RPU (radio processing unit) architecture extends the company’s Ensigma line with a design geared to low power consumption more than high performance, said Richard Edgar, director of communications technology marketing. Rather than a chip itself, it’s a blueprint for chip makers to design processor cores.
The Whisper architecture can be used for Wi-Fi, Bluetooth Classic, low-power Bluetooth Smart, NFC (near-field communications), GNSS (Global Navigation Satellite System) and other current or emerging wireless technologies. Imagination already sells the Ensigma Explorer architecture for devices such as set-top boxes that need high speed, but it designed the Whisper technology for equipment that will never send big streams of packets.
“For IoT, the criteria are different,” Edgar said. “It’s small amounts of data, occasionally.” For example, a temperature sensor in a home might take readings every 15 minutes and send a few hundred bytes. Whisper might also be used in industrial sensors, wearable devices or smart electrical grids, he said.
Whisper is designed for use in chips built with the MIPS architecture, which Imagination acquired in 2012. It can be implemented in a MIPS chip specifically for communications or built into a single chip that also handles application processing and other tasks, Edgar said. The Whisper is scheduled to ship in a series of different versions starting in the fourth quarter.
It’s hard to say whether the Omron-Holst vibration-harvesting design could power a device using Imagination’s new architecture, because there are many ways to measure energy, Edgar said. But the voltages it could generate are within the right range.