—We present an adaptive controller that requires limited model information for stabilization, command following, and disturbance rejection for mult-input multi-output minimum-phase discrete-time systems. Specifically, the controller requires knowledge of the open-loop system's relative degree as well as a bound on the first nonzero Markov parameter.… (More)
results of . This note, therefore, unveils a link between polynomial hyperbolicity and stability. Finally, as pointed out in [3, Sec. 18.9], the applications of frequency response convexity in robust control have only been minimally explored. The explicit LMI formulation described in this note may motivate further research along these lines.… (More)
— This paper is the second part of a pair of papers, which together present a direct adaptive controller for discrete-time systems that are possibly nonminimum phase.
— We extend retrospective cost adaptive control (RCAC) to command following for uncertain Hammerstein systems. We assume that only one Markov parameter of the linear plant is known and that the input nonlinearity is monotonic but otherwise unknown. Auxiliary nonlinearities are used within RCAC to account for the effect of the input nonlinearity.
— In this paper we investigate the robustness of an extended version of retrospective cost adaptive control (RCAC), in which less modeling information is required than in prior versions of this method. RCAC is applicable to MIMO possibly nonminimum-phase (NMP) plants without the need to know the locations of the NMP zeros. The only required modeling… (More)
— We address the problem of adaptive command following and disturbance rejection for a nonlinear planar multilink mechanism interconnected by torsional springs and dashpots. We consider a nonlinear multilink mechanism where a control torque is applied to the hub of the multilink mechanism , and the objective is to control the angular position of the tip,… (More)
— We present a direct adaptive controller for discrete-time (and thus sampled-data) systems that are possibly nonminimum phase. The adaptive control algorithm requires limited model information, specifically, knowledge of the first nonzero Markov parameter and the nonminimum-phase zeros (if any) of the transfer function from the control to the performance.… (More)
— We address the model reference adaptive control problem for a nonlinear multilink planar arm mechanism, where links are interconnected by torsional springs and dash-pots, a control torque is applied to the hub of the mechanism, and the objective is to control the angular position of the last link. It is known that the linearized transfer function for the… (More)