Figure 1: Navigation under different constraint specifications. (a) Attractor to go behind an obstacle and a repeller to avoid going in front of an obstacle. (b) Combination of attractors to go along a wall. (c) Combination of attractors and repellers to alternate going in front of and behind obstacles, producing a (d) Lane formation with multiple agents under same constraints. (e)-(h) Dynamic constraints used to avoid navigating in front of vehicles. AbstractPath planning is a fundamental problem in many areas ranging from robotics and artificial intelligence to computer graphics and animation. While there is extensive literature for computing optimal, collision-free paths, there is little work that explores the satisfaction of spatial constraints between objects and agents at the global navigation layer. This paper presents a planning framework that satisfies multiple spatial constraints imposed on the path. The type of constraints specified could include staying behind a building, walking along walls, or avoiding the line of sight of patrolling agents. We introduce a hybrid environment representation that balances computational efficiency and discretization resolution, to provide a minimal, yet sufficient discretization of the search graph for constraintaware navigation. An extended anytime-dynamic planner is used to compute constraint-aware paths, while efficiently repairing solutions to account for dynamic constraints. We demonstrate the benefits of our method on challenging navigation problems in complex environments for dynamic agents using combinations of hard and soft constraints, attracting and repelling constraints, on static obstacles and moving obstacles.

Path planning is a fundamental problem in many areas, ranging from robotics and artificial intelligence to computer graphics and animation. Although there is extensive literature for computing optimal, collision-free paths, there is relatively little work that explores the satisfaction of spatial constraints between objects and agents at the global navigation layer. This paper presents a planning framework that satisfies multiple spatial constraints imposed on the path. The type of constraints specified can include staying behind a building, walking along walls, or avoiding the line of sight of patrolling agents. We introduce two hybrid environment representations that balance computational efficiency and search space density to provide a minimal, yet sufficient, discretization of the search graph for constraint-aware navigation. An extended anytime dynamic planner is used to compute constraint-aware paths, while efficiently repairing solutions to account for varying dynamic constraints or an updating world model. We demonstrate the benefits of our method on challenging navigation problems in complex environments for dynamic agents using combinations of hard and soft, attracting and repelling constraints, defined by both static obstacles and moving obstacles.Keywords path planning, spatial constraints, navigation, anytime dynamic planning, potential fields Disciplines Computer Sciences | Engineering | Graphics and Human Computer Interfaces CommentsThe preprint version title is Constraint-Aware Navigation in Dynamic Environments; it was published in its final form as Planning Approaches to Constraint-Aware Navigation in Dynamic Environments.This journal article is available at ScholarlyCommons: http://repository.upenn.edu/hms/139 Constraint-Aware Navigation in Dynamic Environments AbstractPath planning is a fundamental problem in many areas ranging from robotics and artificial intelligence to computer graphics and animation. While there is extensive literature for computing optimal, collision-free paths, there is little work that explores the satisfaction of spatial constraints between objects and agents at the global navigation layer. This paper presents a planning framework that satisfies multiple spatial constraints imposed on the path. The type of constraints specified could include staying behind a building, walking along walls, or avoiding the line of sight of patrolling agents. We introduce a hybrid environment representation that balances computational efficiency and discretization resolution, to provide a minimal, yet sufficient discretization of the search graph for constraintaware navigation. An extended anytime-dynamic planner is used to compute constraint-aware paths, while efficiently repairing solutions to account for dynamic constraints. We demonstrate the benefits of our method on challenging navigation problems in complex environments for dynamic agents using combinations of hard and soft constraints, attracting and repelling constraints, on static obstacles and moving obstacles.

This work demonstrates the use of depth panoramas in the construction of detailed 3D models of extended environments. The paper describes an approach to the acquisition of such panoramic images using a robotic platform that collects sequences of depth images with a commodity depth sensor. These sequences are stitched into panoramic images that efficiently capture scene information while reducing noise in the captured imagery. Scene structure is extracted from the panoramas and used to register a collection of panoramas to obtain coverage of extended areas. The presented approach maintains fine geometry detail in 3D reconstructions, uses a modest amount of memory, and enjoys excellent scaling characteristics across large environments.