Simultaneous path planning and trajectory optimization for high-speed sorting system

Abstract

This article presents a strategy for efficient sorting path planning and trajectory optimization with multiple constraints. The proposed strategy is applicable to typical high-density sorting applications. It plans the sorting path while optimizing each trajectory. The total stroke traveled by the end effector to complete the sorting task is shortened, and the efficiency of the production line is correspondingly facilitated. Thus, this article designs bow-shaped trajectories by analyzing the work process of the production line to ensure the smooth transition of the end effector and bow-shaped trajectories are based on the starting point and the end point of each sorting action. The modified trapezoidal acceleration and deceleration algorithm is used to optimize each sorting trajectory, which ensures that each sorting action is executed quickly and stably. Simultaneously, the greedy strategy is applied to plan the sorting task, which further shortens the total stroke of the end effector and improves the efficiency of the production line. A specific cost function is also designed to improve the planning strategy to prevent the occurrence of missing materials and enhance the adaptability of the sorting system. In consideration of the efficiency of the sorting system is significantly improved by this approach, the effectiveness of the proposed strategy in this article is thus verified compared with existing ones by experiments. In addition, the impact of the conveyor speed on the sorting system is also discussed.

Challenges for Future Robotic Sorters of Mixed Industrial Waste: A Survey

“…A well-known method to sort moving objects on the conveyor is first-in first-out (FIFO) using a SCARA [172]. Several timeminimum plans of path or trajectory for parallel link robots that handle moving objects have been generated in previous studies [173], [174], [175]. Chen et al [176] proposed to segment the sorting area based on the assumed maximum velocity of a robot to reduce the computational load of the robot's velocity planning.…”

Robotic Sorting on the Grid

“…Path planning (for one or multiple agents) is another popular area of research. [9] uses path-planning techniques to design an algorithm for sorting elements into a grid with a single robotic arm. Research in object arrangement by distributed mobile robotics systems, though, is sparse.…”

Minimum-jerk trajectory planning pertaining to a translational 3-degree-of-freedom parallel manipulator through piecewise quintic polynomials interpolation

“…By investigating the handling process of practical production line, the most frequently used trajectory of pick-and-place operation is a bow-shaped trajectory, 41 which is approximately considered as an inverted U-shaped trajectory. As depicted in Figure 8, the red solid line in the dexterous workspace ( W t ) of 3-PUU PKM denotes the presupposed inverted U-shaped trajectory for a flexible pick-and-place application.…”