What is the purpose of a singularity avoidance routine in robot programming?

The purpose of a singularity avoidance routine in robot programming is to prevent the robot from entering or closely approaching singular configurations, which can lead to unpredictable robot behavior, excessive joint speeds, and potential damage to the robot. A singularity is a configuration in which the robot loses one or more degrees of freedom, meaning that it cannot move in certain directions or orientations. At or near a singularity, small movements of the robot's end-effector can require extremely large and rapid movements of the robot's joints. This can exceed the joint speed limits, cause the robot to vibrate violently, or even damage the robot's mechanical components. A singularity avoidance routine typically involves monitoring the robot's joint angles and Cartesian position, and modifying the robot's path to avoid configurations that are close to singularities. This might involve slightly altering the robot's path, changing its orientation, or using redundant degrees of freedom to maintain a safe distance from the singularity. For example, if a robot is approaching a singularity where its wrist joints are aligned, the singularity avoidance routine might adjust the robot's wrist angles to maintain a more favorable configuration. By implementing singularity avoidance, robot programmers can ensure smooth, predictable, and safe robot motion.