This paper presents results on the output regulation of a single-input multi-output (SIMO) rotationaltranslational actuator (RTAC) system. The results focus primarily on stability and robustness, which are studied in light of the presence of externally generated exogenous input signals. Two exosystem types were investigated and tested. Obtained results answers the question of asymptotic stabilization and tracking of a desired trajectory in the presence of a dynamic exosystem. The results confirmed the working theory of robust stabilization using output feedback techniques, borne out of differential-geometric observer design principles. The utilized design showed good stability results which compares favourably with existing works on RTAC stabilization.