轮式爬壁机器人转向稳定性研究

Research on steering stability of wheeled wall-climbing robot

针对四轮爬壁机器人在铅垂壁面上转向失稳的问题展开研究。首先,基于机器人驱动轮与铅垂壁面相互作用的赫兹接触理论,提出了一种机器人摩擦力模型,利用线性积分算法求解出机器人驱动轮转向过程中的纵向摩擦力、横向摩擦力和转向阻力矩;然后,通过机器人动力学建模,推导出转向过程中的驱动力矩关系式,并利用MATLAB仿真得出不同转弯半径、不同磁吸附力和不同负载质量所对应的驱动力矩值随转向角近似呈正弦变化趋势。最后,进行了机器人转向稳定实验,结果显示驱动力矩的实测值与仿真值基本吻合。仿真和实验结果表明,控制转弯半径为0 m、调节磁吸附力为1 000 N和限定最大负载质量为27 kg,能够保证机器人转向稳定,有效解决轮式爬壁机器人转向失稳的问题。研究结果可为四轮爬壁机器人的路径规划和转向稳定性控制提供理论依据。

It is launching a research on the instable problem of the four-wheel wall-climbing robot during the steering process on the vertical wall.First of all,based on the Hertz contact theory that the robot driving wheels interacted with the vertical wall,a friction model for robot was proposed,and then the longitudinal friction,lateral friction and turning resistance torque during the whole steering process of robot driving wheel were solved by using the linear integral algorithm.Furthermore,the dynamics model was used to derive the driving torque relation.The torque values that corresponded to different turning radii,different magnetic adsorption forces and different load weights were calculated by the MATLAB software,which were approximately sinusoidal with the steering angles.Finally,the steering stability experiment of the robot was carried out,and the results showed that the measured and simulated values of the driving torque were basically in agreement.Simulation and experimental results indicated that,when controlling the turning radius to 0 m,adjusting the adherence-based force to 1 000 N and limiting the maximum load weight to 27 kg,the steering stability of the robot could be guaranteed and the instable problem of robot during the steering process could be effectively solved.The study results provide the theoretical foundation for path planning and the steering stability control of four-wheel wall-climbing robot.