Abstract:

A hierarchical task planning method with multi-constraint is presented for space manipulator. The process of task planning is separated into two hierarchies：mission profile analysis and task node planning. A representation method for working environment using state matrix and state mask is proposed, according to the space manipulator’s characteristic. Then, three kinds of original tasks and operators are defined based on those matrixes. A sequence of original tasks can be derived by applying hierarchical task network to a complex task. A sequence of task node of the original task which cannot be executed directly because of some constraints can be calculated by an improved A* algorithm, and optimization problem is introduced into the calculation. The feasibility and effectiveness of the proposed task planning method are verified by simulation.

Key words: A* algorithm, hierarchical task network, task plan, space manipulator