煤矿履带巡检机器人多体动力学建模及越障仿真

Multi-body dynamics modeling and obstacle surmounting simulation of tracked inspection robot in coal mine

针对煤矿井下底板路面变化多样,履带巡检机器人行走机构行驶动态特性复杂,底板路面对履带行走机构响应较大,表征和模拟履带-底板路面相互作用的行驶特性较困难。特别是台阶型路面,履带行走装置在越障时其机身上仰姿态过高、落地时履带受到的冲击较大。基于履带地面力学理论,通过一定数量的经验常数确定煤矿底板路面参数,采用柔性体多体动力学的有限段模型方法建立履带行走机构虚拟样机模型,完成巡检机器人在水平底板路面及台阶型路面环境下的多体动力学仿真实验,其履带与地面的接触力、履带内部的轴套力及履带变形情况与机器人行驶、越障过程相一致,表明建模方法正确;同时得到巡检机器人在不同底板路面状况下,其滑转及滑移率也会随之发生变化,在水平底板路面其履带滑转率较小,但在越障过程中,履带理论速度与实际速度相差较大,特别是履带刚接触到障碍瞬间、以及机器人刚越过台阶型障碍瞬间可达0.78,研究结果可为履带巡检机器人在煤矿井下的智能控制提供理论依据。

In view of various underground coal mine road pavements,the complex dynamic characteristics of the walking mechanism of the tracked inspection robot,and the response of floor pavement to tracked walking mechanism varies greatly.Therefore,it is difficult to characterize and simulate the driving characteristics of track-road pavement interaction.Especially for the road with step,the tracked walking mechanism has a high elevation on the fuselage when it surpasses the obstacle,and the tracked suffers a great impact when it lands.Based on the theory of traced vehicle terramechanics,this paper determines the parameters of coal mine road pavement by a certain number of empirical constants.A virtual prototype model of tracked walking mechanism is established by using the finite segment model method of flexible multi-body dynamics,and completes the simulation experiment of tracked inspection robot under horizontal road pavement and step-shaped pavement.The results show that the contact force between the track and the ground,the variation trend of the bushing force inside the track and the deformation of the track are consistent with the process of the robot’s driving and obstacle surmounting,indicating that the modeling method is proper.At the same time,the slip and skid rate of the inspection robot will also change under different pavement conditions.In a flat road pavement its track slip rate is smaller;however,in the process of obstacle crossing,the theoretical speed of the track differs greatly from the actual speed,especially when the track just touches the obstacle and when the robot just crosses the step type obstacle,with the speed reaching 0.78.The research results can basically provide theoretical reference for intelligent control of tracked inspection robot in underground coal mine.