Design And Motion Control Of A Spherical Robot With Control Moment Gyroscope

Spherical robot refers to one kind of mobile robot that has a ball-shaped case including all its mechanisms, control devices inside it. The ball-shaped case works as walking device of the robot. Compared with traditional wheeled and tracked mobile robots, the flexible spherical robot can provide efficient protection for the driving mechanisms, sensory devices and control devices because all of them are placed inside the shell. The robot can restore stability after brief irregular motions if it collides with obstacles. Even if it occurs that the robot falls from a height or meets with other dangerous situations, it can still continue to work because there are no overturning problems. That holds the spherical robot is superior to traditional wheeled or tracked mobile robots for navigation in unknown or varying territories, such as lunar explorations, social service establishments, disaster areas such as earth quakes, etc.Limited by the totally enclosed spherical shell and the special walking style of rolling, existing spherical robots usually lack exteroceptive sensors, such as laser, vision camera and sonar. So they have weak capability of environmental perception and low precision of motion control.Aiming at the above problems, this paper proposes a new type of spherical robot with control moment gyroscope(CMG) based on the improvement of existing spherical robot. According to the robot's mechanical structure and dynamic model, the robot control system is designed and the physical robot is set up to complete some experiments.The main contents of this paper are as follows:(1) This paper presents a spherical robot with CMG, designs the mechanical structure of the spherical robot and kinetic modeling based on the motion principle of the robot, simplified and decoupled.(2) Based on the linearization dynamic model, the motion controller is designed including inner-loop speed controller and outer-loop posture controller of spherical robot. The Adams virtual prototype is established and simulated by MATLAB / Simulink to verify the performance of the robot controller.(3) The whole control system based on the spherical robot is proposed and designed, including the motion control subsystem, the motion actuator subsystem,the energy system, the software system and the remote control system. The paper analyses the compositions, functions and inner relationships of the various subsystems.(4) The physical spherical robot is developed and experimented to test the motion performance of the robot and the controller.