4WD-4WS型床椅一体化机器人室内定位与点镇定控制研究

Research on Indoor Positioning and Point Stabilization Control of 4WD-4WS Wheelchair-Bed Robot

摘要:

以床椅一体化机器人为研究对象,通过设计相应的运动控制器,并结合所搭建的组合导航定位测控系统,实现了室内环境下的点镇定控制。首先,设计了一种四轮转向-四轮驱动模式的全向床椅机器人样机,并对其运动学进行分析；其次,通过不连续坐标变换,用极坐标形式表示当前位姿与目标位姿间的全局控制误差,并选取合适的位姿误差变量对系统模型进行描述,设计出一种基于位置闭环的全局反馈控制器；继而,根据控制器的需要,设计搭建基于卡尔曼滤波的IMU/UWB组合导航定位系统,实现床椅一体化机器人的全局实时精确定位；最后,采用Lyapunov函数法,对所设计控制器中的控制律进行稳定性分析。MATLAB仿真实验与现场实验均表明所设计的点镇定方法控制效果良好。

Abstract:

Taking the bed and chair integrated robot as the research object, by designing the corresponding motion controller and combining with the integrated navigation positioning measurement and control system, the point stabilization control in the indoor environment is realized. Firstly, a four-wheel steering and four-wheel driving driven omnidirectional wheelchair-bed robot prototype is designed and implemented, and its kinematics is analyzed. Secondly, through discontinuous coordinate transformation, the control errors between the current and target poses are expressed in polar coordinates, and the appropriate pose error variables are used to describe the system model, and a global feedback controller based on position closed loop is designed; Then, according to the needs of the controller, an IMU / UWB integrated navigation and positioning system based on Kalman filter is designed and built to realize global real-time precise positioning of wheelchair-bed robot; Finally, the stability analysis of the control law in the designed controller is performed using the Lyapunov function method. Both MATLAB simulation experiments and field experiments show that the designed point stabilization method has good control effect.