Abstract
A new state-matching digital redesign method to nd the lifted dual-rate pulse-amplitude-modulated (PAM) and pulse-width-modulated (PWM) digital controllers from a predesigned, state-feedback, continuous-time controller is presented. The proposed method provides close matching of the states of the continuous-time controlled analog system with those of the digitally redesigned system (including intersample behavior). The redesigned lifted dual-rate controller enables the digitally controlled X-38 vehicle to track the desired trajectory while remaining insensitive to modeling parameters, initial conditions, and exogenous disturbances for larger sample times than existing methods. The X-38 will require a PAM controller for commanding the electromechanical actuators that operate its aerodynamic surfaces for ight in the atmosphere. PWM control will be used to command the reaction control jets during orbital operations. The proposed method provides a new alternative for indirect digital design of state-feedback multivariable continuous-time systems.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
