Design and implementation of a computer-controlled sensor-equipped robot end effector

Abstract

This paper describes the conceptual design, development, and application of a sensor-equipped, computer-controlled robot end effector. A commercially available, parallel jaw pneumatic gripper is retrofit with tactile, force, torque, and position feedback and interfaced to an industrial robot. The integrated system is applied to a variety of typical robot tasks. This work demonstrates that the retrofit of a standard pneumatic robot gripper with sensor feedback and servo control is an economically and technically viable alternative to the purchase of a commercial unit. The developed servo gripper features fully programmable finger gap and grip force capabilities, controllable from within a robot program. The control strategies are discussed briefly. Real-time optimization of the controller gains and the development of appropriate gain schedules are also discussed. The developed system has been applied to a variety of tasks that are difficult or impossible using conventional grippers. These include fragile object handling, detection of part presence, quality control (part dimension measurements), and picking from closely packed trays. The tactile feedback can be utilized in a wide variety of applications, such as part identification and orientation, and in-process robot path modification.