Dynamic visibility checking for vision-based motion planning

An important problem in position-based visual servoing (PBVS) is to guarantee that a target will remain within the field of view for the duration of the task. In this paper, we propose a dynamic visibility checking algorithm that, given a parametrized trajectory of the camera, determines if an arbitrary 3D target will remain within the field of view. We reformulate this problem as the problem of determining if the 3D coordinates of the target collide with the frustum formed by the camera field of view during the camera trajectory. To solve this problem, our algorithm computes and compares the shortest distance between the target and the frustum with the length of the trajectory described by the target in the camera's coordinate frame. Furthermore, we demonstrate that our algorithm can be combined with path planning algorithms and, in particular, probabilistic roadmaps (PRM). Results suggest that our algorithm is computationally efficient even when the target moves in the vicinity of image borders. In simulations, we use our dynamic visibility checking algorithm in conjunction with a PRM to plan collision free paths while providing the guarantee that a specific target will not leave the field of view.

Authors

• Simon Léonard
• Elizabeth A. Croft
• James J. Little

Keywords

• Robot kinematics
• Cameras
• Visual servoing
• Service robots
• Robot sensing systems
• Orbital robotics
• Feedback
• Heuristic algorithms
• Trajectory
• Road accidents
• Field Of View
• Computational Efficiency
• Shortest Distance
• Path Planning
• Pathfinding
• Dynamic Algorithm
• Coordinate Frame
• Trajectory Length
• Target Coordinates
• Target Frame
• Frustum
• Camera Field Of View
• Algorithm Checks
• Collision-free Path
• Arbitrary Target
• Upper Bound
• Shortest Path
• Linear Interpolation
• Visual Feedback
• Joint Space
• Dijkstra’s Algorithm
• Cartesian Space
• Image Coordinates
• Backward Motion
• Assembly Line
• Final Angle
• 3D Point
• Amount Of Rotation