Journal of Guidance, Control, and Dynamics, cilt.20, sa.5, ss.1049-1052, 1997 (SCI-Expanded)
A nonlinear feedback law for an aerodynamically unstable rocket is presented. This is proximate time-optimal in the sense it marches near minimal-time behavior. Unlike the proximate time-optimal laws of Pao and Franklin, it is continuous and, thus, produces a continuous control function that is likely to produce little response in the presence of small plant imperfections. It has been shown that the system is asymptotically stable as long as the initial state is within the RZ of the unstable plant. Continuous proximate time-optimal (CPTO) laws for two more second-order plants, including the double-integrator plant, have been obtained. CPTO laws for third- and higher-order systems have also been obtained.