Finite-time Visual Servo Control for Robotic Fruit Harvesting in the Presence of Fruit Motion

摘要

Many developed and rapidly developing countries around the world are exploring autonomous robotic solutions for harvesting fruit due to their potential for increased productivity over manual harvesting. However, economic feasibility of robotic harvesting depends at large on two factors: harvesting efficiency, which is a quantitative measure of successful harvest, and harvest time. To maintain economic advantage, it is imperative that the robotic system achieves high harvesting efficiency and the harvest time for the robotic operation should be comparable to its manual counterpart. One of the challenges impacting harvesting efficiency in outdoor environments is that of the fruit motion. Exogenous disturbances such as wind gusts, robot-tree contact, and canopy unloading forces may cause the fruit to oscillate about its equilibrium position. Therefore, it is of interest to develop robust control systems that successfully harvest fruit in the presence of fruit motion and guarantee finite and computableharvest times. By leveraging on our prior work in finite-time visual servo control, this paper proposes a new continuous terminal sliding mode visual servo controller to guarantee finite-time regulation of the robot to a target fruit in the presence ofnonlinear fruit motion. Simulation results are presented to validate the proposed controller.