Accession Number : ADA208074

Title :   Residual Vibration Reduction in Computer Controlled Machines.

Descriptive Note : Doctoral thesis,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB

Personal Author(s) : Singer, Neil C.

Report Date : FEB 1989

Pagination or Media Count : 241

Abstract : Control of machines that exhibit flexibility becomes important when designers attempt to push the state of the art with faster, lighter machines. Three steps are necessary for the control of a flexible plant. First, a good model of the plant must exist. Second, a good controller must be designed. Third, inputs to the controller must be constructed using knowledge of the system dynamic response. There is a great deal of literature pertaining to modeling and control but little dealing with the shaping of system inputs. Chapter 2 examines two input shaping techniques based on frequency domain analysis. The first involves the use of the first derivative of a gaussian exponential as a driving function template. The second, a causal filtering, involves removal of energy from the driving functions at the resonant frequencies of the system. Chapter 3 presents a linear programming technique for generating vibration-reducing driving functions for systems. Chapter 4 extends the results of the previous chapter by developing a direct solution to the new class of driving functions. A detailed analysis of the new technique is presented from five different perspectives and several extensions are presented. Chapter 5 verifies the theories of the previous two chapters with hardware experiments. Because the new technique resembles common signal filtering, chapter 6 compares the new approach to eleven standard filters. The new technique will be shown to result in less residual vibration, have better robustness to system parameter uncertainty, and require less computation than other currently used input shaping techniques. Keywords: Vibrations, Oscillations, Teleoperators, Flexible manipulators, Machinery. (KT)

Descriptors :   *COMPUTER APPLICATIONS, *DAMPING, *ROBOTICS, *VIBRATION, COMPUTERS, CONTROL, DYNAMIC RESPONSE, ENERGY, FILTERS, FREQUENCY, FUNCTIONS, INPUT, LINEAR PROGRAMMING, MACHINES, MANIPULATORS, METHODOLOGY, OSCILLATION, PARAMETERS, REDUCTION, REMOVAL, RESIDUALS, RESONANT FREQUENCY, SHAPE, SIGNALS, SOLUTIONS(GENERAL), TELEOPERATORS, TEMPLATES.

Subject Categories : Machinery and Tools
      Cybernetics

Distribution Statement : APPROVED FOR PUBLIC RELEASE