Path-constrained rendezvous

Introduction

Path-constrained rendezvous is the process of moving an orbiting object from its current position to a desired position, in such a way that no orbiting obstacles are contacted along the way. It is a more constrained instance of the general problem of orbital rendezvous.

When no orbiting obstacles are a consideration, the problem of moving from one orbital position to another is straightforward, and many efficient algorithms are available to plan the necessary maneuvers. Depending on the desired time taken to accomplish the rendezvous, there are literally an infinite number of possible rendezvous paths.

The presence of obstacles posing a collision risk complicates the problem. The shortest-time rendezvous might be made infeasible by obstacles, so a path requiring more time would have to be employed. For instance, if the purpose of the rendezvous is to rescue an astronaut in distress on the far side of a large space station, one might well need quickly to find the rescue path requiring minimal time to execute.

A natural object of study is the problem of maneuvering in the vicinity of a large orbiting sphere, since a collision with a more complex structure can be avoided by selecting rendezvous paths that avoid contact with a virtual sphere enclosing the structure. Early research considered the problem of departure and arrival points lying on the surface of an orbiting sphere. This led to a pair of necessary conditions called the Tangential Departure and Tangential Arrival conditions.

Selected Publications

• Stern, S. A. and Soileau, K. M., "Operational Implications for Path-Constrained Rendezvous," Proceedings of the AIAA Guidance, Navigation and Control Conference, Snowmass, CO, August 19-21, 1985, pp. 812-820.
• Soileau, K. M. and Stern, S. A., "PathConstrained Rendezvous: Necessary and Sufficient Conditions," Journal of Spacecraft and Rockets, Vol. 23, September-October 1986, pp. 492-498.
• Stern, S. A. and Soileau, K. M., "Inadequacy of Single-Impulse Transfers for Path-Constrained Rendezvous," Journal of Spacecraft and Rockets, Vol. 24, May-June 1987, pp. 282-284.
• Soileau, Kerry M., "Defining Optimal Point-to-Point Transfer Surfaces for Orbital Path-Constrained Rendezvous," Proceedings of the AAS/NASA International Symposium, Greenbelt, MD, April 24-27, 1989, pp. 103-107.