Research And Design On Driving Control Of Ultrasound Motor For Flexible Mechanical Finger Drive

Dexterous manipulator has a broad demand and application prospect in aerospace,nuclear energy development,medical equipment and other cutting-edge fields.Recent decades of research,most of the dexterous manipulator drive is the electromagnetic motor drive control,but the electromagnetic motor structure characteristics and operating characteristics limit the development of dexterous manipulator,so it is necessary to study the new driving mode.Ultrasonic motors(USM)is a kind of new principle direct drive motor.Ultrasonic vibration excited by inverse piezoelectric effect of piezoelectric ceramics is used as the driving force to drive the rotor motion through the friction force between the stator rotors.Compared with the traditional electromagnetic motor,it has low speed,large torque,small size,no electromagnetic interference,fast response,noiseless operation,power failure self-locking and other outstanding characteristics.Due to its remarkable advantages in discontinuous operation and precision control,it can be used as a driver for dexterous finger joints with mechanical structure constraints.The research topic of this paper is the design of ultrasonic motor driving control for dexterous manipulator.The main research content is the design of the driving controller of ultrasonic motor for dexterous fingers,the establishment of the step response speed model of ultrasonic motor,the ultrasonic motor speed control system based on LADRC and the flexible control of dexterous fingers.The research objectives of this paper are following:1.For the ultrasonic motor used for smart fingers,the parameters of the ultrasonic motor were determined,and the step response speed model of the ultrasonic motor and the step response speed model of the upper FM were established.2.Design the driving and control circuit of the ultrasonic motor,including the control system based on F28335 DSP,the driving circuit based on push-pull inverter amplification circuit,the protection circuit based on current feedback,the sampling and conditioning circuit,and the calculation and design of the matching circuit between the driving circuit and the motor of the ultrasonic motor.Device type selection and parameter calculation are carried out for each part of the circuit.3.According to the established ultrasonic motor step response speed model and up-fm step response speed model,the linear LADRC speed control system is designed by combining with ADRC,and the parameters are calculated and simulated.The simulation results show that LESO can observe the modeling error,model parameter perturbation and external interference of the ultrasonic motor,and compensate it by PD controller.The motor can reach a stable speed state in a very short time.4.The ultrasonic motor speed position cascade control strategy suitable for this topic is adopted,focusing on the position control of the motor.The positioning process adopts the method of series and compound grading speed reduction to realize the flexible control of the ultrasonic motor driven by smart fingers.In order to design and composite classification speed down the way,the self-locking power error detection,determine the classification speed down gate value,designs the flexible control process:according to the characteristics of the ultrasonic motor power cuts self-locking according to relative to the movement of a target location,adopt different ways of startup and change speed,realize flexible control of ultrasonic motor.5.The ultrasonic motor driving control platform for dexterous mechanical finger driving is built,and the validity of the ultrasonic motor speed control method based on LADRC is verified.For the three levels of speed adopted in this paper,the motor can fully track the target speed within 20ms.The results show that the positioning error of the motor is small,which meets the positioning accuracy requirement of the dexterous mechanical finger.