Vibration as an aid in robotic peg-in-hole assembly

This dissertation presents an analytical and experimental investigation of vibration assisted engagement for parts mating. A dynamic model of assembly is established by using Lagrange\u27s equation for impact to derive impact equations for a robotic manipulator in peg-in-hole assembly. The model can be used to analyze part motion and contact force in the mating of parts by robots. The impact equations of a SCARA robot are derived using this model and utilized to investigate how robot configuration, insertion speed, chamfer angle, coefficient of restitution and other system parameters affect impulsive force and departure angle in the assembly of a peg with a chamfered hole in the presence of position errors. In the analytical investigation, how the vibration amplitude, vibration frequency, frequency ratio, phase angle, uncertainty and tolerance of the assembly system affect the engagement time is analyzed. An algorithm is developed to determine the required time for engagement given a set of assembly and vibration parameters. An intelligent force-based approach is used in conjunction with this algorithm to aid mating of parts and is implemented in experiments to verify analytical results