Ascent guidance for a satellite rendezvous.
A discussion of the problem of guiding a vehicle to a rendezvous with a space platform or satellite. Rendezvous not only requires matching vehicle and satellite positions, but the two velocity vectors must also be identical. A further complication is that the geometric relationship between a given launch site and the satellite is a function of time. As a consequence, the ascent trajectory is generally nonplanar, and the time of launch is a critical factor. For an ideal rendezvous, the vehicle must be guided so that at the end of propulsion its three components of velocity and position are the same as the corresponding satellite variables. In practice, the residual errors in position and velocity at the end of the ascent phase serve as the initial conditions for a terminal guidance period during which the vehicle is brought into proximity with the satellite.