A reactive control system for a partially guided small sounding rocket

摘要

Most small sounding rockets are unguided vehicle. Stability is solved aerodynamically using fins and/or rapidly spinning the vehicle and trajectory is determined by the azimuth and elevation of the launch pad as the rocket usually fly a gravity turn. Access to upper atmosphere usually require two or three stages and the presence of fins on the upper stages inflict a penalty on the stability of the launcher in the start configuration. The paper presents a modification made to an existing launcher suggested by the need to add dead weight for stability when flying small payloads. By eliminating the fins from the second stage and using a RCS for active stability and control of the upper stage several opportunities arise: the aerodynamic configuration is simpler and the stability in the start configuration improved, drag is reduced a bit, non-gravity turn evolutions are possible and special payload requested attitudes (mainly orienting a camera towards ground) are conceivable. Of course, this require a new OBC with enhanced sensors and new navigation and flight control algorithms.