Magee, David P. | Search NASA

NASA NTRS1991

The application of input shaping to a system with varying parameters

The original input shaping technique, that was developed in earlier work, is summarized, and a different definition for residual vibration is proposed. The new definition gives better insight into the ability of the input shaping method to reduce vibration. The extension of input shaping to a system with varying parameters, e.g., natural frequency, is discussed, and the effect of these variations is shown to induce vibration. A modified command shaping technique is developed to eliminate this unwanted motion.

Magee, David P.↗

NASA NTRS1991

Experimental verification of modified command shaping using a flexible manipulator

A brief discussion introduces the original input shaping method applied to a system with varying parameters. A change in parameters causes a vibration in the system and a modified command shaping technique is created to eliminate this unwanted motion. Using a two degree of freedom (DOF) flexible manipulator, experiments are conducted by varying perturbations to input trajectories to compare the modified method to a previously used adaptive proportional plus derivative (P.D.) control method. The control scheme that produces the smaller magnitude of resonant vibration at the first natural frequency of the robot is considered the more effective control method.

Magee, David P.↗