Abstract: Loaders are often used in harsh working environments such as the construction industry and mining industry.The autonomous operation of loaders can effectively guarantee the safety of employees,which has become a development trend in the field of construction machinery.The shovel trajectory is a key factor affecting the energy consumption of the autonomous operation of loaders.At present,scholars have proposed some trajectory planning methods aiming at optimal energy consumption.However,most of these methods only take the trajectory of the bucket tip as the planning goal but ignore the influence of the bucket angle on the energy consumption during the autonomous shovel loading process.Aiming at the above problems,a method for shoveling trajectory planning of loader based on beetle antennae search was proposed.The kinematic mathematical model of the working mechanism was established,and the relationship between the position of bucket tip,bucket angle and the displacement of the vehicle,boom cylinder and bucket cylinder was obtained.Based on the bucket tip position model and bucket angle model,the planning scheme characterized by the shovel depth and angle coefficient was determined to form a series of alternative shovel trajectories.Using these shoveling trajectories as the search space,a new heuristic search method named beetle antennae search was used to search for the approximate optimal shovel trajectory of loader aiming at the lowest fuel consumption per unit shovel weight.To verify the energy-saving and consumption reduction effect of the shoveling trajectory planning method,a 5t loader test platform was built,and a comparison experiment of manual shoveling operation and autonomous shoveling operation was carried out.The experimental results showed that the mean fuel consumption per unit shovel weight was only 14.13 ml·t-1  when the shoveling trajectory planning method of the loader based on the beetle antennae search was used for autonomous shoveling operations,which was 20.35% lower than that of manual shoveling operations.These results show that the proposed shoveling trajectory planning method could significantly reduce the energy consumption of loaders.

Key words: wheel loader, automatic shoveling, shoveling trajectory, trajectory planning, beetle antennae search

摘要： 装载机常用于建筑、采矿等恶劣工作环境,实现其自主作业可以有效保障从业人员安全,已成为工程机械领域的发展趋势。铲掘轨迹是影响装载机自主作业能耗的关键因素,目前已有学者提出了一些以能耗最优为目标的轨迹规划方法,但这些方法大多仅以铲斗斗尖位置为规划目标,忽略了铲装过程中铲斗转角对自主作业能耗的影响,导致装载机自主作业能耗仅能达到局部最优。针对上述问题,提出一种基于天牛须搜索的装载机铲掘轨迹规划方法,首先建立作业机构运动数学模型,得到铲斗斗尖位置、铲斗转角与车体位移、动臂油缸和转斗油缸位移的关系,进而基于斗尖位置模型和铲斗转角模型确定以铲掘深度和转角系数表征铲掘轨迹的规划方案,形成一系列备选铲掘轨迹,最后以此为搜索空间采用新兴的启发式搜索方法——天牛须搜索方法,搜索以单位铲掘重量油耗最低为目标的近似最优的装载机铲掘轨迹。为验证该铲掘轨迹规划方法的节能降耗效果,搭建了5吨级装载机测试试验平台,并进行了人工铲掘作业和自主铲掘作业对比实验。实验结果表明,采用基于天牛须搜索的装载机铲掘轨迹规划方法进行自主铲掘作业时,单位铲掘重量油耗的平均值仅为14.13 ml·t-1,与人工铲掘作业相比降低达20.35%。

关键词: 装载机, 自动铲掘, 铲掘轨迹, 轨迹规划, 天牛须搜索