Open-loop Control

Open-loop control executes a pre-planned trajectory without using sensor feedback during execution — the robot simply follows the commanded positions or velocities regardless of what actually happens. This is appropriate for highly repeatable tasks in controlled environments, such as CNC machining or pick-and-place on a fixed conveyor. Open-loop control is fast and simple but fails when disturbances occur, because no corrective action is taken. In contrast, closed-loop (feedback) control continuously compares the actual state to the desired state and applies corrective commands, making it far more robust for robot learning in variable environments.