PATH PLANNING OF TRACTOR-TRAILER ROBOT BY FAST MARCHING METHODE (FMM)

This paper deals with motion planning of Tractor-trailer robots، which are car-like robot dragging several trailers with no driving force. Each trailer has a nonholonomic kinematic constraint which increases the complexity of the path planning problem. We solved this problem by implementing the Equivalent Size concept، which depending on the size، number، and link-point positions of trailers، transforms a tractor-trailer path planning problem into a single car-like robot path planning problem. In this paper a new path planning algorithm is proposed for car-like robots which utilizes the Fast Marching Method (FMM)، which is a numerical method for solving the Eikonal differential equation، and the concept of Virtual Obstacles. The algorithm is fast، works independent of the shape of obstacles، and is easy to implement. To evaluate the quality of the solutions the algorithm is compared with the grid search and nonholonomic RRT algorithms. The results showed that the new method has by far lower runtime compared to the other algorithms، while producing short and smooth paths.