Research on Control System of Spherical Robot
|School||Harbin Institute of Technology|
|Course||Aviation Aerospace Manufacturing Engineering|
|Keywords||spherical robot control modeling PID|
Spherical robot is a new-style of mobile robot with a global or approximately spherical shell, and takes the rolling as their main motion mode, internal drive and external friction as motion motive power, which has characteristics of tumbler and moving in all directions. The spherical robot to be researched can face special task environment such as anti-terrorism, investigation, searching and rescuing, and have the ability of vibration resistance, rapid motion speed and strong pavement adaptability. This thesis colligates merits and demerits of all spherical mobile robots to raise a kind of double motors driving double polarizations spherical robot. And the method of controlling fixed-point rotation and velocity of rolling motion is presented.Firstly, the dynamic characteristics of rolling motion with basic nonlinear dynamics method, concluding fixed-point of phase plane and phase trajectory is researched in this paper. The DC motor rotating speed and robot velocity controls and reducing vibration are realized through PID control. The problem of big polarization mass acceleration in the starting process is solved by S planning method. Secondly, the dynamic model of fixed-point rotation motion is built with theorem of moment of momentum. Motion scheme based on dividing rotation process into three stages of static, viscous and slip is proposed by analyzing the relationship of polarization mass swing angle, spherical shell rotation angle and friction resistance moment. The numerical simulations indicate the effectively of motion control method.Finally, hardware system and two-stage control are designed. The system takes high performance processor dsPIC as the core of control and calculation, implements feedback control by motion information supplied by MEMS inertial original, and drives motor by high efficiency drive. And comparing experiments of open-loop and PID control are conducted to testify the system performance.