Simulate the Motion of the Human Arm

How to simulate the motion of a human arm on a robotic arm.

What are the sensors and software to use? other than IMUs and barometers.

Watch the following video starting from (03.40) for a demo.

Thank you.

There are many parts to such a project.

On the operator: Notice how at 4:20 she places electrodes to get nerve / muscle impulses from his arm.

On the robot: The angle of each joint needs to be known (potentiometer or encoder?). The question of what feedback to provide the user determines what sensors to install, though how to provide the feedback to the user is another issue.

Software: This is really up in the air and likely custom developed (C+, Python etc.)

I’m all aware of the system including the feedforward and feedback. I’m not concerned with the feedback.

I have a 6-DOF arm robot, and I want it to follow my arm’s motion as in the video (03:40). I’m not concerned with the hand either. Because this is another work that I’m getting done already.

In brief, how to get information about my hand’s position and feed it forward to the robotic arm to take the same motion.

Essentially like this?

You just need some way of measuring each rotation. In the video, mechanical rotary potentiometers were used. Note that if you’re measuring angular acceleration using an IMU or gyro, there is often drift. An IMU can also measure the force of gravity which can help with orientation. Sensors you’d use to make the feedback arm therefore might include:

  • Rotary potentiometer
  • Encoder (magnetic or optical)
  • IMU (gyro, accel)
  • Stretch and bend sensors (best for fingers)

The difficulty comes in creating the mechanical structure and incorporating the sensors. The software would be entirely custom. You’d need to know the communication protocol of the arm that you have to be able to adjust each joint angle.

Would you please list these components available in the shop?

My apologies, normally I add links. The specific choice of product will depend on your needs and design.

For example, a simple 10k rotary potentiometer would work, but since it uses wipers, the accuracy is low and the noise is high. If you opt for an encoder, you’ll need to find a way to zero it since it provides relative rather than absolute positioning. The microcontroller you select needs to (ideally) have the IO for all the sensors, and programmable in a language you are comfortable with.

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