This is probably more for those interested in technology more than those interested in theremins..
Plessey have been involved in biometric monitoring for years - but it seems that the trchnology has now advanced well beyond the ability to detect biological signals through clothing etc.. It seems they can detect changes to electrical fields over long distance, and are applying this technology to gestural control interfaces.
A brief overview of Epic Gestural control (or imPart) can be found here -
>> Plessey’s Director of Business Development, Steve Cliffe, explains why he thinks CES 2013 is the right place to debut imPart: “CES is the perfect showcase for this stunning new technology. People are amazed at how sensitive it can be at picking up very small signals even at a distance of up to 100 cm without physical contact.” <<
Ok, I suspect it will be many years before this Epic Technology becomes common - but apparently they have now managed to produce their sensors "cheaply" - what exactly they mean by "cheaply" I do not know - their early sensors were far from cheap - but were for a market which could afford it.
It certainly (to me) looks like a technology which could be used for musical applications, and possibly replace capacitive sensing for theremin type instruments of the future.. Probably long after I am pushing up daisies though..
Difficult to find / link to the relevant sections on the site - so I paste some info below:
Because of EPIC's mode of operation, it can be used to detect any disturbance in the local electric field at distances of up to several tens of meters. The human body, because it acts as a large container of conducting/polarizable material, causes a large perturbation in the electric field and so presents an easily detectable target for the sensor. Sitting a few meters away from the sensor, one has only to raise the sole of one's foot to create a strong signal. Arrays of sensors can be used to provide spatial resolution and therefore the location of a target. Such arrays can also distinguish between humans and quadrupeds because the time signature of the response is a direct function of cadence. Such a system of sensors could perhaps be used for border security in remote areas.
The ability of EPIC to resolve signals unique to various muscles or groups of muscles presents opportunities for improved man-machine interaction. For example, a quadriplegic who currently depends on either a unicorn stick or a suck/blow tube to issue commands to equipment within his or her local environment could achieve a faster and more efficient interaction using EPIC for eye tracking and detection of activity in any muscle groups still under voluntary control. Alternatively, because EPIC can assign a unique signature to the use of certain muscle groups, it opens up many possibilities for interfacing with and controlling prosthetic limbs.