OGBPS: Orientation And Gradient Based Path Smoothing Algorithm For Various Robot Path Planners It is significant to plan a smooth trajectory for highspeed wheeled mobile robots working in a cluttered environment. The trajectory generated by most of the previously proposed path planners is not smooth enough for robot motion, especially under kinodynamic constraints. An improved smoothing algorithm is proposed in this work as a solution for most of the previously proposed path planners to deal with the rugged paths, which may cause abrupt and angular turns of robots. The improved solution we proposed could be applied to many mainstream path planners (like Theta*, A*, RRT, RRT*, RRT, SORRT*, PRM) as a postsmoothing algorithm, which is called orientation and gradientbased path smoothing (OGBPS). The OGBPS algorithm is derived from both orientationanglebased and gradientbased path deformations to obtain a highquality path. The objective of path deformations in this work is to improve path smoothness, lower maximum curvature and path length. Sufficient simulation experiments are well conducted to demonstrate the effectiveness of our approach. It is verified that the proposed algorithm can improve the quality of the previous path while respecting the kinodynamic constraints through experiments. The simulation results indicate the advantages (smaller maximum curvature and smaller path length) of the proposed algorithm compared with several stateoftheart smoothing algorithms.

From Reeds and Shepps to ContinuousCurvature Paths Most path planners for carlike robots compute Reeds and Shepp pathsu0027u0027 made up of line segments connected with circular arcs. Such paths have a discontinuous curvature that makes them difficult to track (curvature is related to the orientation of the front wheels). The purpose of this paper is to present one of the first path planner for carlike robots that computes paths with continuouscurvature and upperbounded curvature derivative (curvature derivative is related to the steering velocity). The approach presented herein relies upon a steering method, i.e. an algorithm that computes paths without taking into account the obstacles of the environment, which is then embedded within a general path planning scheme in order to deal with the obstacles and thus solve the full problem. The paths computed are made up of line segments, circular arcs and clothoid arcs.