Release Time:2019-07-01  Hits:

Indexed by: Journal Article

Date of Publication: 2019-04-01

Journal: INSTRUMENTS AND EXPERIMENTAL TECHNIQUES

Included Journals: EI、SCIE

Volume: 62

Issue: 2

Page Number: 256-265

ISSN: 0020-4412

Key Words: Deformation; Error compensation; Three term control systems, Compensation scheme; Functional relationship; Large displacements; Measuring precision; Mechanical deformation; Self-tuning fuzzy PID; Small displacement; Structural deformation, Displacement measurement

Abstract: A method for measuring large displacements >800 mm with a precision of 0.0094% and an accuracy of 0.0125%, realizing the principle of measurement with walking pattern and utilizing two analog high-precision small displacement sensors as the measuring unit is presented. A self-tuning fuzzy PID controller with high adaptability is used to make two identical measuring subsystems work coordinately for reaching a large displacement measurement. A series of tests are conducted to verify the effectiveness of the method. Theresults show that this method has a good performance. The influence of the mechanical deformation on measuring precision is discussed, and the functional relationship between mechanical structural deformation and measuring error is found in the experiment. A feasible compensation scheme is built to eliminate the error caused by mechanical deformation.