School of Mechanical Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
Shaanxi Key Laboratory of Mine Mechanical and Electromechanical Equipment Intelligent Monitoring, Xi'an 710054, China.
Sensors (Basel). 2023 Apr 30;23(9):4412. doi: 10.3390/s23094412.
Aiming at the problems of grab failure and manipulator damage, this paper proposes a dynamic gangue trajectory planning method for the manipulator synchronous tracking under multi-constraint conditions. The main reason for the impact load is that there is a speed difference between the end of the manipulator and the target when the manipulator grabs the target. In this method, the mathematical model of seven-segment manipulator trajectory planning is constructed first. The mathematical model of synchronous tracking of dynamic targets based on a time-minimum manipulator is constructed by taking the robot's acceleration, speed, and synchronization as constraints. The model transforms the multi-constraint-solving problem into a single-objective-solving problem. Finally, the particle swarm optimization algorithm is used to solve the model. The calculation results are put into the trajectory planning model of the manipulator to obtain the synchronous tracking trajectory of the manipulator. Simulation and experiments show that each joint of the robot's arm can synchronously track dynamic targets within the constraint range. This method can ensure the synchronization of the position, speed, and acceleration of the moving target and the target after tracking. The average position error is 2.1 mm, and the average speed error is 7.4 mm/s. The robot has a high tracking accuracy, which further improves the robot's grasping stability and success rate.
针对抓取失败和机械手损坏的问题,本文提出了一种在多约束条件下机械手同步跟踪的动态矸石轨迹规划方法。机械手抓取目标时,由于机械手末端和目标之间存在速度差,是产生冲击载荷的主要原因。在该方法中,首先构建了七段式机械手轨迹规划的数学模型。通过以机器人的加速度、速度和同步性为约束,构建了基于时间最小化机械手的动态目标同步跟踪的数学模型。该模型将多约束求解问题转化为单目标求解问题。最后,采用粒子群优化算法对模型进行求解。将计算结果代入机械手的轨迹规划模型中,得到机械手的同步跟踪轨迹。仿真和实验表明,机器人手臂的各个关节都能在约束范围内同步跟踪动态目标。该方法可以保证运动目标和跟踪后的目标的位置、速度和加速度的同步性。平均位置误差为 2.1mm,平均速度误差为 7.4mm/s。机器人具有较高的跟踪精度,进一步提高了机器人的抓取稳定性和成功率。