Structural vibrations degrade the performance and productivity of electromechanical systems. This dissertation develops implementable boundary controllers for distributed parameter models of mechatronic systems. The controllers stabilize all motion of the distributed system using a small number of practical sensors and a single control input. Lyapunov theory, integral inequalities, and passivity theory prove stability. Numerical simulations based on Galerkin discretized models and experiments on a PC/DSP test stand verify the performance improving characteristics of the controllers. String-mass, cable, and flexible link gantry systems are investigated.; First, a class of boundary controllers damps transverse vibrations in a string-mass system. A novel Lyapunov functional and the Meyer-Kalman-Yakubovich Lemma prove strong exponential stability. Impulse response experiments show the vibration decays six times faster using a five term controller than without control.; Second, a three term (PDC) boundary controller stabilizes the three dimensional motion of a nonlinear elastic cable. Boundary position, velocity, and departure angle drive the boundary control force. Out-of-plane impulse response simulations and experiments show a 50% decrease in the settling time compared to passive boundary damping.; Third, the PDC boundary controller is applied to a flexible, single link gantry robot. The controller feeds boundary position error, velocity, and shear force to the boundary control force, allowing precise gantry payload position control and damping of the flexible beam vibration. The experimental step response shows a 90% settling time reduction over passive regulation.; Finally, an observer-based, backstepping controller is developed for the flexible, single link gantry robot driven by a brushed DC motor. The observer eliminates the need for boundary velocity measurements. The backstepping controller allows voltage level input to the mechatronic system. The fast motor dynamics cannot be neglected because they are slow relative to high order vibration modes. Through an embedded desired current, the integrator backstepping controller generates the desired force on the mechanical subsystem. Experimental vibration decay improves by a factor of twenty over the open loop response for step desired gantry position inputs.
展开▼
