Novel Algorithm for Simulating the General Parachute-Payload System: Theory and Validation

摘要

A novel algorithm to model and simulate the general parachute-payload system was developed. This algorithm adopted the multibody system method and the Kane equation to analyze dynamically the parachute-payload system. Two main aspects of the algorithm were discussed: treating the parachute system as a special multibody system and establishing universal methods to select the general coordinates. The chosen general coordinates were suitable for the parachute-payload system to describe the kinematics of the system. The Kane equation and its augmented form aiming at systems with variable mass were applied to create kinetic equations. Additionally, some special issues in simulating the parachute-payload system, such as parachute opening and contacting between the parachute cluster and the sling system, were further analyzed within a unified framework. A solver to numerically implement the proposed algorithm was developed by using C++. The solver was able to read the formatted configuration files of a concrete parachute system and to uniformly conduct the simulation for the different stages during the entire airdrop process. The algorithm and solver were verified by some examples obtained from literature or generated by commercial software and were applied successfully to investigating many kinds of parachute-payload systems.