As far as I know no further details of the "Emma" have been published. So, I've gone ahead with my own ideas of how vibrating motors may reduce tremor.

I've built my first prototype using 3 flat vibrators.

The device runs off an Arduino Uno, which is connected to my laptop. This allows me to have better control of the settings, but at the cost of being tethered to the machine. It will be easy to make the device stand-alone, with the electronics about the size of a pack of cards, and later down to watch size. The vibrators (diameter about 8mm and height about 4mm) are positioned on a velcro strap around my wrist.

The user experience is pleasant, and you quickly forget that it's there. The device makes a noise. I find this OK, but other people might object.

Does it work? I don't know. I've convinced myself that with a bad setting (e.g. 5Hz) it makes my tremor worse. I've not managed to find any setting which has definitely causally reduced my tremor, but 0.5Hz and 10Hz look promising. Even with the placebo effect working to my advantage, I've been unable to find any setting which has stopped all tremors. However, and it may be just coincidence, I've had many cases where I've changed the frequency and the tremor has reduced within seconds. Unfortunately, because the tremors are so variable this does not prove that the device works.

At any time only one vibrator is in focus. You can set how long it is switched on for. Focus then goes to the next vibrator, and so on until a lap around the wrist has been completed. (It is in this sense that I mean the frequencies above, e.g. 5Hz with 3 vibrators delivers an individual pulse of vibration every 1/15th second.)

The next thing to do is to find a way of collecting statistics in as blind a way as possible. In addition to measuring the short-term impact on tremor I need to monitor the effect on bradykinesia and any long-term effects.

If anyone wants any help in building one of these devices, please get in touch.

John