球形轮组结构及其控制系统设计

Design of Spherical Wheel Formation Structure and Its Control System

研究的球形轮组是通过控制3个全向轮的转速和方向维持自身不倒,在不改变方向的前提下能在平面上任意移动的系统。其具有非线性、强耦合和欠驱动问题,因此需要进行动力学分析和控制系统的设计。采用建模软件建立球形轮组物理模型,并完成球形轮组的制作和电路设计;用拉格朗日方程展开动力学分析,将球形轮组简化成全向轮、球轮和机身三部分,得出电机的扭矩与全向轮的力和力矩的关系;结合动力学分析的内容设计一套串级PID控制算法与ROS系统建立的上位机联合处理传感器采集的姿态数据,计算出电机的控制变量;将物理模型与控制算法相结合,利用仿真软件验证其能够实现自平衡。

The spherical wheel group studied is a system that can move freely on the plane without changing direction by controlling the rotation speed and direction of three omnidirectional wheels.It has nonlinear,strong coupling and underdrive problems,so dynamics analysis and control system design were needed.The physical model of the spherical wheel set was established by modeling software,and the production and circuit design of the spherical wheel set were completed.Lagrange equation was used to develop the dynamic analysis,and the spherical wheel was simplified into three parts,namely the full-directional wheel,the spherical wheel and the fuselage,and the relationship between the motor torque and the force and moment of the omnidirectional wheel was obtained.Combined with the dynamic analysis,a set of cascade PID control algorithm was designed and the ROS system was established to jointly process the attitude data collected by the sensor and calculate the motor control variables.The physical model was combined with the control algorithm,and the simulation software was used to verify that it can realize self-balancing.