Research And Design On Omnidirectional Mobile Platform And Control System

Omnidirectional mobile robot is a branch of robot,based on the omnidirectional wheel.Through the control system,the omnidirectional mobile robot can achieve degrees of freedom in any direction.The omnidirectional mobile platform is the motion execution part of the omnidirectional mobile robot and is the basis for the robot to implement other functions.This paper takes the robot omnidirectional mobile platform as the research object,based on the Mecanum wheel,and uses the STM32 master chip as the core hardware of the slave computer.The Raspberry Pi is used as the control computing center of the host computer to develop an omnidirectional mobile platform.The main work of this paper includes the following:(1)The basic motion principle of omnidirectional mobile platform is studied.The working principle of the general omnidirectional wheel is analyzed,and the inverse kinematics equation of a single general omnidirectional wheel is derived.The layout of two types of omnidirectional wheels is analyzed,and the OMNI wheel and the Mecanum wheel are obtained.The inverse kinematics equations under different layouts,in which the kinematic Jacobian matrix of the Mecanum wheel 4 wheel set is obtained.For the Meinham wheel 4 wheelsets have different layouts,their different sports characteristics,combined with the subject to choose a more reasonable Mecanum wheel4 wheel set layout,and designed the omnidirectional mobile platform Motion structure and bridge independent suspension mechanism.(2)The distributed control and priority control mechanism of the omnidirectional mobile platform is studied.The control system for slave computer is established in the omnidirectional mobile platform,and the Raspberry Pi is used as the host computer control system of the computing control center.According to the idea of distributed control and priority control,the control system is divided into five control subsystems:Host computer communication control subsystem,IMU calculation subsystem,Motion control subsystem,Fault detection subsystem,Close proximity detection control subsystem,Display control subsystem.(3)Research and implementation of the control task subsystem of the omnidirectional mobile platform.Based on the control system of the embedded realtime operating system Free RTOS,five control tasks are designed: the ROS?Task task realizes the data processing with the host computer,the Detect?Task task realizes the fault detection of all the devices of the entire control system,and the IMU?Task task realizes the attitude of the IMU.The data fusion of the sensor,the stable data,the Chassis?Task task,combined with the Mecanum wheel motion model,realizes the motion control of the omnidirectional mobile platform,and the Uesr?Task task realizes the working state of the lower computer.