Research On Controller For Micro Scanning Platform Based On Piezoelectric Stack

In recent years, precision engineering has played an increasingly important role in scientific research, industrial production and people's life. Studying the precision technology is very important.A controller of this article as a part of a precision instrument, combined with technology index and timing requirements, has been designed to suit the controller development program, meeting technology index and timing control requirements, after analyzing the piezoelectric stack actuator and micro scanner's characteristics of the structure and working principle. And also implements the design of hardware and software in accordance with the parameters requirement.First of all, the hardware of micro scanning platform controller has been designed in this paper. Due to the limits of instrument-specific size, the controller must be designed in the limited size of 91 mmx 125mm, PCB design should be based on the principle of small size and integration. MSP430F169 microcontroller has been selected as the master controlling chip. Controller's hardware is divided into the master control module, driving signal amplification module and position feedback module, and designed independently in each module. Micro scanner controller has been finally built.Then according to the timing requirements, controller's software has been designed. Master chip of hardware can produce a given waveform through programming in embedded C. A modular approach has been used in software programming. The overall function is divided into clock module, internal DAC output module, external DAC output module, ADC sampling method and control algorithm module, and the program design for each module has been completed independently. Simultaneously the PID simulation and programming of control algorithms are done, realizing the control of micro scanning controller.Finally, the controller's performance has been tested and optimized. The method of serially connecting resistance in the circuit has been used to view changes of current. Find that the power of positive supply is 2.92W, and give an optimizing recommendation. Single peak current has been measured as 25.20mA. Burr voltage has been reduced about 76.2%. The control error is just 0.5 um in 50g load after introducing PID close-loop feedback. The need parameter for controller has been tested and optimized, verifying that the designed micro scanning controller's performance meets the design requirements, and control plan is rational.