基于前馈补偿的轮腿式机动平台姿态自适应控制

Adaptive Attitude Control of Wheel-legged Mobile Platform Based on Feedforward Compensation

在通过复杂路面障碍时,轮腿式机动平台的轮端负载较大,且地面对轮胎的外力会突然变化,会显著降低机身姿态的控制精度,并容易导致轮胎脱离地面失稳等问题。为提高平台的地形适应能力和稳定性,提出一种基于前馈补偿的平台姿态自适应控制策略。构建平台的逆运动学模型和动力学模型,考虑轮-地接触点垂向支撑力和纵向驱动力实现轮-地接触状态的实时估计,结合腿部高度观测器和轮-地接触状态估计器获得腿部垂向补偿高度,兼顾平台车轮运动稳定性和姿态自适应控制精度。考虑平台机身动量和角动量,利用二次规划算法优化的轮端虚拟驱动力求解前馈补偿力矩,以实现平台的运动精确控制。仿真结果表明,该方法可以有效提高轮腿式机动平台在崎岖路面环境下的姿态自适应控制精度和轮胎驱动稳定性,为在复杂工况下轮腿式机动平台执行侦察等任务奠定基础。

When passing through complex obstacles,a wheel-legged mobile platform bears a relatively large load on the wheel end,and the external force acting on the tire from the ground undergoes sudden changes.This significantly reduces the precision of the platform's attitude control and can lead to tire instability and loss of contact with the ground.To improve the terrain adaptation and stability,an adaptive attitude control strategy for the platform based on feedforward compensation is proposed.Considering the vertical support force and longitudinal driving force at the wheel-ground contact point,the inverse kinematic model and dynamic model of the platform are constructed.And the real-time estimation of the wheel-ground contact state is achieved,and the leg height observer and wheel-ground contact state are combined to perform feedforward compensation to adjust the leg's vertical height,balancing the platform's wheel motion stability and adaptive attitude control accuracy.Furthermore,considering the momentum and angular momentum of the platform,the virtual driving force at the wheel end is optimized by the quadratic programming algorithm to solve the feedforward compensation torque and thus enable the precise control of platform motion.The simulation results show that the proposed method can improve the adaptive attitude control accuracy and tire driving stability of the wheeled-legged mobile platform,laying the foundation for its performing reconnaissance and other tasks in complex working conditions.