A Path Planning Strategy for Multi-Robot Moving with Path-Priority Order Based on a Generalized Voronoi Diagram

Abstract

This paper proposes a new path planning strategy called the navigation strategy with path priority (NSPP) for multiple robots moving in a large flat space. In the space, there may be some static or/and dynamic obstacles. Suppose we have the path-priority order for each robot, then this article aims to find an efficient path for each robot from its starting point to its target point without any collision. Here, a generalized Voronoi diagram (GVD) is used to perform the map division based on each robot’s path-priority order, and the proposed NSPP is used to do the path planning for the robots in the space. This NSPP can be applied to any number of robots. At last, there are several simulations with a different number of robots in a circular or rectangular space to be shown that the proposed method can complete the task effectively and has better performance in average trajectory length than those by using the benchmark methods of the shortest distance algorithm (SDA) and reciprocal orientation algorithm (ROA).

Path Planning of Multi-Type Robot Systems with Time Windows Based on Timed Colored Petri Nets

“…Combining the linear transformations for the exclusive, collaborative, and the public task regions, i.e., Equations ( 4), (8), and (10), Problem 1 can be solved by the following MILPP:…”

“…For the temporal requirement, we assumed that the task regions r 69 , r 3 , r 24 , r 45 , r 21 , r 10 , and r 11 should be visited in the time windows [10,12], [3,5], [10,15], [17,25], [8,22], [3,8], and [15,20], respectively. Therefore, the task requirement ϕ for the MTRS can be represented as follows: ϕ = (r 65 , E 1 ), (r 69 , E 1 , [10,12]), (r 3 , E 2 , [3,5]), (r 24 , E 3 , [10,15]), (r 45 , E 3 , [17,25]), (r 21 , S 2 , [8,22]), (r 21 , S 3 , [8,22]), (r 10 , S 1 , [3,8]), (r 10 , S 3 , [3,8]), (r 13 , A), (r 48 , A), (r 11 , J, [15,20]), (r 37 , J), (r 68 , J), which requires that task region r 65 be visited by a C 1 robot; task region r 69 be visited by a C 1 robot in the time window [10,12], task region r 3 be visited by a C 2 robot in the time window [3,5]; task region r 24 be visited by a C 3 robot in the time window [10,15]; task region r 45 be visited by a C 3 robot in the time window [17,25]; task region r 21 be visited by C 2 and C 3 robots in the time window [8,22]; task region r ...…”

“…To tackle the problem of collaborative coverage of multiple robots in complicated environments, a novel multi-robot persistent coverage strategy was proposed in [9] to take into account the environmental complexity and the differences in robot path lengths. If robots have different priorities and there are both static and dynamic obstacles in the workspace, a navigation strategy with priorities was presented [10]. To complete some collaborative tasks within time constraints, the distributed planning of robots was researched in [11,12] to ensure that enough robots are present at the task destinations within the given time constraints.…”

A New Multirobot Path Planning With Priority Order Based on the Generalized Voronoi Diagram

“…The dilation width depends on the size of the obstacle, and the larger the size of the obstacle, the wider the width of the dilation. Then referring to [25], we can generate many red points called Voronoi corners around the gray boundary of each obstacle and the boundary of the map shown in Fig. 3.…”

“…It is pity that the paper did not provide a comparison between their proposed method and other algorithms. In paper [25], the navigation strategy with path priority (NSPP) algorithm assigns the priority to each robot such that the path of high path priority robot is shorter than that of low path priority robot in the same space and collision-free is guaranteed too. However, a drawback is that the higher path priority robot sometimes may need to stop and wait for a lower path priority robot to pass through for avoiding a collision.…”