Leg sensor and Robotic Leg

I am looking for advice on how to use sensors on a leg to replicate the motions on a robotic leg.


  1. What sensors should I look at for getting the position to replicate?

2)What sort/number of motors should I look at for the robot?

interesting project.

It really comes down to how heavy your robot is and how quick you plan on moving. A lot of people choose servo motors and keep their robot small. Keep in mind that the human body is all curvy and bendy and doesn’t conform to simple joint movements. you’ll either have to simplify your movements when puppeteering or make your robot super complex.

I’ve seen people use accelerometers to gauge angles on various parts of their body and build custom software to calculate position data.
It all sounds hard but for simple movements which do not require accurate position tracking but only angles to copy on a robot this could be achievable with cheap 9axis accelerometers and a kalman filter on an arduino. I’ve messed around with this before with not to many dramas.

What are your ideas/size requirements for this robot?

A series of flex sensors / variable resistors (Nintendo power glove style) is a way I have detected body position before.

Here is a video a super star little ninjas I worked with made a couple of years back. She was using flex sensor to trigger key presses using an Arduino Leonardo but there is no reason you couldn’t use the same principle to trigger servos (in fact has totally been done…)

Then she made another video with three flex sensors.

Do you may be able to put one on the front and back of a joint like a knee and take readings to translate to your servos or whatever you’re using.

The other way could be to use something like the Myo armband from Thalmic Labs to detect what the muscles are doing https://www.myo.com