Wearable computing tomorrow’s world?

Materials World magazine
24 Jul 2012

Anyone who saw the Google Glass advert – a point-of-view clip showing a young man wearing a pair of glasses that overlay maps, diary appointments and hands-free video phone calls onto his daily routine – could be forgiven for feeling a sense of dread that the dark, technology-obsessed future predicted by science fiction writers is coming to pass. With Apple being granted its own patent for a heads up display (HUD) last month, the war for the space in front of our eyes is about to begin. 

Researchers at the Department of Electrical Engineering at the University of Washington, USA, have already designed, built and tested a single pixel contact lens display on a rabbit eye. The chip consists of an antenna, a power harvesting and radio integrated circuit made from silicon, metal interconnects, insulation layers and a transparent sapphire chip (covered in a gallium nitride buffer layer) containing a micro-light emitting diode. 

Though the device seems to be the first step towards Terminator-style tracker vision, it is early days yet. Firstly, the human eye has a minimum focal distance of a few centimetres – a problem for a lens-based display. The academics at Washington propose two solutions – either light from LEDs could be focused using subsidiary lenses, or alternatively, beams from vertical cavity surface emitting lasers could be used to create an image. 

Another issue is that contact lenses must be porous to allow the human eye to breathe, and the prototype is made from a non-breathable material. But as with many technological innovations, once a concept has been proven, it is likely that a process of refinement, lightweighting, and increasing functionality has been set in motion. The team at Washington has already set its next goal of fabricating multi-pixel LED chips. 

Meanwhile, technology manufacturers are busy exploring the real-world uses that sunglass-style HUDs can offer. American company Vuzik has a wide range of augmented reality glasses aimed at defence, consumer and entertainment markets, that allow users to overlay their field of vision with a range of information, including data, 3D models and live streaming of footage. The goggles have already been used by the Italian Coast Guard to control small remote drones equipped with infrared cameras to monitor heat differences in the water and catch illegal toxic waste dumpers. The company also recently announced that it had been awarded US$150,000 from the US Office of Naval Research to develop a lightweight, low-cost, high-performance HUD for military training, research that could lead to a HUD incorporated in the visor of a helmet. 

Elsewhere, Tokyo-based camera giant Canon recently released its mixed reality (MR) system for the Japanese market. The MR system uses videoenabled goggles and allows multiple designers to work on a 3D design of a product simultaneously and evaluate it, which can reduce the number of prototypes needed, saving time and material costs. ‘As product lifecycles become progressively shorter, it is increasingly necessary for the manufacturing industry to introduce products to market in a timely manner,’ says Mototada Toriumi, from Canon’s Image Communications Products Operations team. The MR system has a variety of applications, such as deciding the layout of a site before construction or inspection while possible future uses could include surgical procedure simulations.


Flexing its muscles 

To really take off as a sector, wearable computing needs to be flexible, and make use of novel power solutions, thinks Xiadong Li, Professor of Mechanical Engineering at the University of South Carolina, USA. ‘We have seen large, cumbersome desktop computers evolve into portable laptops. What is next? I think that the answer is in wearable computing. In the near future we will be able to carry a flexible computer that can roll up just like a piece of paper’. 

A flexible energy storage device is necessary for this to happen, says Li, whose team has found a way to convert a cotton T-shirt into a supercapacitor. After soaking the shirt in a solution of fluoride and baking it in an oxygen-free oven, they found the surfaces of fibres in the fabric had converted from cellulose to activated carbon, while still being flexible. The team coated the individual fibres of the T-shirt with ‘nanoflowers’ of manganese oxide 1nm thick to enhance electrode performance. ‘This is a low-cost, green technology that is also a new and innovative biotechnology,’ says Li. He adds that although at present the T-shirt can currently only store power, his team are developing a cotton-enabled energy device with the capability to capture energy as well. 

Power issues notwithstanding, perhaps an important question to ask is why do people need to wear electronics? Why would they want to? Becky Stern is Director of Wearable Electronics at open-source hardware specialists Adafruit, based in New York. She believes it is because ‘humans are constantly improving and extending their capabilities through tools, and those tools are getting smaller and more integrated with our bodies’. 

Adafruit has a wide variety of customisable, makeyour- own-wearable-computing kits available. Many of them include a small round printed circuit board (PCB) made from fibreglass with copper connecters and gold-plated solder, designed to act as the brains inside wearable electronics. Stern thinks the opensource nature of such tools could help the sector take off. ‘I think the DIY-ers are driving innovation when it comes to wearable computing. Homemade devices can be made fast, loose, buggy [containing bugs], and published online immediately, even if their silver conducting wires have to be re-stitched in a month. Companies that want to take something like an iPodcontrolling snowboarding jacket to market have to spend years in R&D to sell a product that won't easily break.’ 

Stern adds that innovations in wearable computing could have health benefits for many people wearing electronics such as pacemakers or insulin pumps. ‘Would you hate your mandatory medical device less if it synced with your iPad, or if you could access the sensor data to build a heartbeat visualiser or monthly chart of your insulin levels?’ she says. ‘Making use of the information about your physical being and activity is one of the main motivators for wearing electronics.’ 

With the future notoriously hard to predict, the way we see the world of wearable computing shaping up may be way off. ‘I think a lot of companies are going to try and have head-mounted versions of mobile phones,’ says Professor Phillip Torr, Head of the Computer Vision Group at Oxford Brookes University. ‘But it is not yet clear whether that will succeed because people might not want to be distracted by HUDs or want to wear glasses. Wearable computing will introduce a whole other dimension of social issues. Will people like it if you’ve got a wearable camera filming them all the time?‘