This little vest is quite the feat — for the visually challenged it’s a new friend and for the gamer it’s a new delight. Found on Hackaday, it’s creator, Sean Benson, has done his homework on sensing.
The skin, a sense organ, contains the biological sensors of touch which are the thermoreceptors (responsible for thermal sensing), the nociceptors (responsible for pain sensing), and the mechanoreceptors (sensitive to mechanical stimulus and skin deformation.) Of the four kinds of mechanoreceptors, the one that is relevant to this project is Pacini corpuscles which respond to vibration.
In order to make good use of those muscles, Sean incorporated 48 vibration motors to surround the wearer’s torso. The motors vibrate at different levels to help indicate an obstacle. This is where it gets tricky, both from a body standpoint, as well as a circuit standpoint. Apparently there is a two point discrimination threshold (TPDT) that is used to distinguish stimuli on the skin. This becomes an important factor when designing wearable touch stimulation devices for the body. Then, there is the consideration of how to actually connect 48 motors to a microcontroller when they need PWM. That would take a large number of pins on one controller, or multiple controllers, which would get bulky fast. Sean was able to use two Adafruit LED Drivers, in conjunction with a Raspberry Pi and Parallax Propeller microcontroller to get things buzzing in a cost effective way. As for depth sensing, he used a Kinect. Check out the vest in test mode.
Sean’s vest also has the ability to add more action in gaming, but to be honest, I’m happy enough with its ability to help those that need it most. Not only can the vest be used as a sensing tool, but it can also be used as an instructional tool to recreate the feeling of blindness for those with sight. There’s no telling how many other inventions might come from this mega motor project, but one thing is for sure. If you want to use Sean’s trick for handling a bunch of motors, you should check out our Learning Guide on LED Driver Breakouts. That’s what I call a good hack for a great cause.
Every Wednesday is Wearable Wednesday here at Adafruit! We’re bringing you the blinkiest, most fashionable, innovative, and useful wearables from around the web and in our own original projects featuring our wearable Arduino-compatible platform, FLORA. Be sure to post up your wearables projects in the forums or send us a link and you might be featured here on Wearable Wednesday!