PWM Control Accuracy for Scratch Drive Actuators
In this paper we investigate the problem of controlling a scratch drive actuator that has two discrete modes of locomotion: forward motion in a straight line, and forward motion with fixed radius curvature. This type of device can be modeled as a two-wheeled vehicle (with the previously stated constraints). By alternating between these two modes of operation, the device can move along a variable-radius curved path. In practice, the robots do not move in a purely straight manner. This paper seeks to quantify the accuracy that can be achieved by switching between the two modes of locomotion. This type of low-level open-loop control facilitates the use of a higher level feedback controller designed for two-wheeled vehicles with a variable turning radius.