As processors shrink and become less power hungry computers are finding their way into places they’ve never been before – on people, animals and in the environment around us.
The smartphones we carry around in our pockets are evidence of just how much computing power can be squeezed out of small batteries.
Shrink the computer down from a smartphone to a simple processor, wireless radio and some sensors and you have a device that can sit collecting data for more than a year before it needs replacing.
The advent of low-power chips of the likes of the Arm Cortex-M0+ processor – which only consumes about 30 per cent of the power of eight and 16 bit processors available today – can be embedded in buildings, everyday objects and clothing to make items ‘aware’ of their environment and capable of intelligent decisions.
One such example of the application of these technologies is LivingPlanIT with its technology to support smart cities that marshal traffic flows to reduce congestion and direct resources to where they are needed.
Another group is working on what it calls computers you can forget about, which sit unseen sucking up information, is the Centre for Speckled Computing at the University of Edinburgh in Scotland.
The devices – known as specks – are able to work for up to a year without being manually charged because they rely on low-power Arm processors, energy efficient radio transmitters and operate in a way that minimises their battery use.
The centre’s test devices are being used to monitor the breathing of NHS patients, to track the movements of wild horses and for low-cost motion capture.
But Janek Mann who is in charge of the hardware and firmware at the Centre for Speckled Computing, predicts an explosion in the use of these embedded devices to capture data in the environment.
“I see it as extending computation from your computer and your mobile phone,” he said.
“You can do more than you can do with a phone or a computer because you can put the sensor in the place where it can be of the most use.
“The point is these are computational devices that you forget about. What’s unique about the devices that we’re building is the extremely low-power nature of them.”
Being able to drop off intelligent sensors in the environment and leave them to report back opens up new applications for computing Mann said.
For example in the case of the RESpeck breathing monitor it is a matchbox-sized device worn by the patient that captures their breathing rate and relays it back to their doctor. The patient just gets on with their daily life, there’s no need for them to charge the device or download the data, it takes care of the process in the background.
Similarly in the case of the device monitoring the horses the speck calculates the animal’s position using the onboard GPS and then relays it back to base stations situated around the nature reserve without the need for any human interaction.
Power demands are minimised by the way they operate. For example, the breathing monitor only transmits when it is in range of a home base station and does so in very short bursts – minimising the drain on the battery. Meanwhile the horse tracker processes data on the device to reduce the amount of data sent, which is 10 times more power efficient than sending raw data to be processed remotely.
The horse tracking device also includes a solar cell that charges the device while it operates.
The device used for motion capture demonstrates the large array of sensors that can be packed onto tiny low-power computing devices today. It includes a gyroscope to measure the orientation of the device, a magnetometer that tells which way is north, a pressure sensor that measures height above sea level and an infra-red thermometer that measures temperature. It also has a radio amplifier that gives it a wireless range of 100m.
But this is only the start according to the Centre for Speckled Computing. Its vision of tomorrow’s low-power embedded computing technology makes today’s matchbox sized devices look as clunky as a tower PC.
The centre’s website predicts a future where specks will be “around 1mm cubed semiconductor grains that can sense and compute locally and communicate wirelessly.
“Each speck will be autonomous, with its own captive, renewable energy source. Thousands of specks, scattered or sprayed on the person or surfaces, will collaborate as programmable computational networks called Specknets.
“Data sensing and information processing capabilities will fragment and disappear into everyday objects and the living environment.”