A centrifuge is a device that is used to separate components in a mixture. In an industrial centrifugation process, the mixture to be separated is placed in the centrifuge and rotated at high speed. The centrifugal force on a particle depends on the mass, radial location, and the angular speed of the particle. This force is responsible for separating the particles in the mixture.
The angular motion and temperature of the container are the two key variables that have to be controlled in a centrifuge. In particular, a specific centrifugation curve is used that consists of an acceleration segment, a constant-speed segment, and a braking (deceleration) segment and this corresponds to a trapezoidal speed profile. An optical encoder may be used as the sensor for microprocessor-based speed control in the centrifuge. Discuss whether an absolute encoder is preferred for this purpose. Give the advantages and possible drawbacks of using an optical encoder in this application