Design and Development of High-Precision Scanning Flexural Mechanism Using PID

Rigid linkage mechanism has narrow accuracy and repeatability. The mechanism offers motion between the joints. A different approach has been made to develop S-type flexure mechanism for high-precision systems. This paper presents the flexural mechanism design with the building blocks. This S-shaped mechanism is developed using a numerical approach to get linear motion. The mechanism is incorporated with a voice coil motor (VCM), optical encoder, and dSPACE 1104 R&D microcontroller board. The S-shaped mechanism is integrated, designed, and developed with system integration and identification of the system. The proportional–internal–derivative (PID) controls the implementation of the mechanism. The system identification is done and performance is evaluated for the natural frequency, damping factor and also evaluated by experimentation for the same. The transfer function is used to build the control system and parameters are tuned with the help of PID. PID implementation in real time imparts the accuracy for positioning at a high scanning speed of 0.5 mm/s.