Many of us have grown up watching science fiction visions of a future where we live in houses that are fully interactive, where our lives are made easier by technological advancements and that reality is getting closer and closer with home automation. We're not quite there yet, but one of the stumbling blocks to this vision may have been recently removed.
In order to have sophisticated tracking, listening and processing system on the scale of a whole building, requires a very large number of small self-powered wireless sensors to surround us. It's the self-powering part of this which has been one of the significant problems thus far. A new generation of ultra-low power microchips could provide a breakthrough.
Inside every chip are transistors which have an electrical current running through them – the level of this current is used to represent either a '0' or a '1' – an 'on' or an 'off'. By using a large number of these, we can build the mathematical, computational systems upon which all computers are based. However, even when the transistor is 'off' it is still using electricity – just a lower current than when it is 'on' and a small amount of current leaks through most transistors when they are in this state.
The new principle is to take advantage of the small charge to perform certain tasks without having to raise the current to the more power-hungry 'on' state. The technology is referred to as 'sub-threshold' and a number of the major chip manufacturers have been investing heavily in this area. One in particular, the Cambridge giant, ARM Holdings (who produced 10 billion chips for the mobile market last year, 2013), has been exploring this concept. Chips capable of simple sensing functions are being developed for release next year (2015) which potentially use 0.1% of the power of existing chips.
The real benefit of such chips is that by operating on such tiny amounts of power, this can be drawn from external environmental factors rather than having to have their own internal power source. For example, a wearable EKG monitor that is powered thermoelectrically from the patient's own body heat has already been constructed. Other sources might include tiny solar cells, piezoelectric devices which can derive energy from movement or even ambient radio wave energy – potentially this could be harnessed.
These devices – which are essentially self-powered in being able to harvest energy from the environment around them – open up a whole new vista of possibilities of micro devices that can be embedded not only into our homes, offices and vehicles but into our very bodies. The 'System-on-Chip' (SoC) paradigm takes a significant step forward and more importantly brings nano-technology closer still.
In just five years, SoC technology has moved from enabling basic computation and connectivity on a mobile phone to being at the heart of all smartphones and early stage ultra-books - all capable of a wide range of functions including audio/video, gaming, communication and productivity. The next five to ten years will see advances far beyond this and a whole new generation of complex technological medical devices within our bodies. The possibilities are endless and with this exciting advancement, science fiction may be looking a little more real before too long.