Design 3D Movable Platform Based On The STM32 Microprocessors

In many cases of medical field,surgons cannot perform operations for themselves due to the complex structure of human joints.In order to complete these operations accurately and steadily in different occasions,an electrical 3D movable platform is designed in the present thesis.The platform is drived by three independent step-motors and controlled by a development board based on ARM.The major work done here is to design a control system of 3D movable platform on the basis of ARM development board.This project adopts an STM32F103 microchip as the system core and is coded in the MDK environment.Only manipulations on a LCD screen can the generate periodic signal which controls the speed and directions of the step-motors.Meanwhile,the control system can receive signals of limit switches installed on each axis of the platform to constrain the platform within a pleasant range.The whole system features a simple structure,a high precision and stable motions.This thesis first presents the control system scheme of the 3D movable platform according to its requirements and some background information.It also gives a brief introduction to the design goals and philosophy.Then,introductions of step-motors are given,including their history,categories,work principle,some important parameters and typical characteristics.Besides,a mathematical model of step-motors is inferred and the different driving methods are studied and compared.The specific step-motors used in our project are also involved.In the aspect of hardware,the system comprises a STM32 development board,a 2.4 inches TFT-LCD screen,three SJ-M415 B step-motor drivers,three 35BYGH28-0504 A step-motors and a Q-120 D power supplier.What follows next is the software.It introduces the development board and the MDK environment.It also give information about UCOSIII and StemWin,in addition to the design and operations of the human-machine-interface.The program has been divided into several relatively independent modules according to their functions,e.g,initialization module,motion control module,interrupt service program module of the timer,PWM module,position limit module and etc.Due to the background information,it requires that the shell of the platform should be designed as compact and light-weight as possible provided that the functions are not affected.Finally,the whole system is tested module by module to meet the predefined requirements.It has been proved that the scheme presented in this thesis is workable and stable and thus practicable.