I'm working on designing an exoskeleton for my senior design project in mechatronics, and I need some advice on sensors to control a feedback control system.
The project I'm working on is an exoskeleton for the arm, with a single joint, probably actuated by hydraulics. The ultimate purpose of our device is to curl weights; it essentially strength booster, but we also want it to be able to have precise angular control, so it can stop or move to any angle between lower and upper arm (for reference our main design constraint is for the device to be as low profile as possible). Also this is something that will be wrapped around the arm rather than a single bar adjacent to the arm, and we want to be able to control the system using only the arm, rather than having a joystick/finger sensors.
So first off, does anyone know of some affordable EMG sensors (less than $100, preferably more around the $50 dollar range, but this may be too much to ask for...) that are accurate enough for the control I've just described? I found some by advancer technologies ( http://www.advancertechnologies.com/p/muscle-emg-sensor-v2.html
), but it's hard to tell how accurate they are. Anyone have experience with these?
I've also been looking at force sensors (we'd probably place these on the inside of a frame that would wrap around the arm, so that when it senses force exerted by the arm, it knows to move), however since this is the first time I've designed anything for feedback control, I'm not entirely sure how accurate of a sensor I will need. I was looking at some on sparkfun, specifically ( https://www.sparkfun.com/products/11207
) but again, I don't know if this type of sensor will be accurate enough. Anyone know if this particular sensor would be sensitive enough? Or are there other places I should be looking for force sensors?
Any suggestions would be greatly appreciated.