Question

We investigated two different methods for measuring velocity: differentiated potentiometer, and differentiated encoder counting. Describe how each method compares in terms of resolution, implementation effort, and, noise in velocity estimate. What are the advantages of using a potentiometer for position and velocity estimation? When would you use a single rotation potentiometer for position or velocity estimation? Describe the advantages of using a dual channel encoder to measure velocity. When would you use an encoder for position and velocity estimation?

Answer 1

Differential potentiometer * Resolution: Resolution is characterized as the minimal amount by which the voltage charges in response to corresponding shaft movement one of the biggest advantage of potentiometer is that the resolution is virtually infinite. A potential is an absolute position sensing device As such when powered on or OFF the potentiometer always known where it is positioned and does not need to return to zero. * Rightarrow noise is caused by variation in the output, caused by transient resistance between resistive element surface, that do not exist in the input. Rightarrow Potentiometer can be designed to fit a variety of custom packages and interfaces. Special design consideration will take into account package size, shaft configuration Rightarrow termination requirements cost is less differential encoder Rightarrow Displacement resolution: Displacement resolution is governed by the number of windows N in the code dist and the digits size r of the buffer.

??Advantage of potentiometer and when would you use this