改进的两轮直立车多回路控制

Improved Multi-loop Control of Two-wheel Upright Vehicle

两轮直立车传统单回路PID闭环算法实现简单,成为常用的基础算法,但直立车系统具有非线性、欠驱动、高阶次、自然不稳定等特点,单级PID不能实时有效地进行调节,且由于直立环与速度环并联产生耦合,导致在车速较高时该方法的控制不稳定。针对这一问题,采用比值法、四元数-互补滤波法和平均速度法提高车辆和环境信息的准确度,并设计了串级行驶和串级转向PID控制系统。经过实际调试和与传统方案的数据对比分析,结果显示,两轮直立车在平衡保持跟踪和循迹方面的稳定性、抗干扰能力以及控制精度都获得了较大提升。

The traditional single-loop PID closed-loop algorithm of two-wheel upright vehicle has become the common base algorithm because of its simple to realize.But the upright vehicle system has the characteristics of nonlinear,underdrive,high order and natural instability,which cannot be adjusted effectively in real time in single-stage PID.And the coupling between the balance control and the velocity control in parallel leads to the instability of the control method at higher speeds.In order to solve this problem,the ratio method,quaternion complementary filtering method and average speed method are used to improve the accuracy of vehicle and environment information,and the PID control system of cascade driving and steering is designed.Through comparing the data of the actual debugging and the traditional scheme,the results show that the stability,anti-interference ability and control accuracy of upright vehicle have been greatly improved in attitude keeping and tracing.