https://hdl.handle.net/1721.1/95692 2026-04-03T19:17:20Z https://hdl.handle.net/1721.1/101750 Supplementary Materials to "Adaptive Output-Feedback Control for A Class of Multi-Input-Multi-Output Plants with Applications to Very Flexible Aircraft" Qu, Zheng; Annaswamy, Anuradha; Lavretsky, Eugene A dominant presence of parametric model uncertainties motivates an adaptive approach for control of very flexible aircraft (VFA). This paper proposes an adaptive controller that includes a baseline design based on observers and parameter adaptation based on a closed-loop reference model (CRM), and is applicable for a class of multi-input multi-output (MIMO) plants where number of outputs exceeds number of inputs. In particular, the proposed controller allows the plant to have first-order actuator dynamics and parametric uncertainties in both plant and actuator dynamics. Conditions are delineated under which this controller can guarantee stability and asymptotic reference tracking, and the overall design is validated on a nonlinear VFA model. 2016-03-22T00:00:00Z https://hdl.handle.net/1721.1/98917 Squaring-Up Method for Relative Degree Two Plants Qu, Zheng; Annaswamy, Anuradha; Lavretsky, Eugene Abstract--- Non-square multi-input-multi-output (MIMO) plants are becoming increasingly common, as the addition of multiple sensors is becoming prevalent. However, square systems are needed sometimes as an leverage when it comes to design and analysis, as they possess desirable properties such as strict positive realness. This paper presents a squaring up method that adds artificial inputs to a class of MIMO plants with relative degree two and stable transmission zeros, where number of outputs exceeds number of inputs. The proposed method is able to produce a square plant that has stable transmission zeros and uniform/nonuniform relative degree, and is used to carry out adaptive control of this class of plants and shown to lead to satisfactory performance in a numerical study. 2015-09-28T00:00:00Z https://hdl.handle.net/1721.1/98482 Supplementary Materials to "Adaptive Output-Feedback Control for Relative Degree Two Systems Based on Closed-Loop Reference Models" Qu, Zheng Abstract--- In this paper, a new adaptive output-feedback controller for multi-input-multi-output (MIMO) linear plant models with relative degree two is developed. The adaptive controller includes a baseline design based on observers and parameter adaptation based on a closed-loop reference model (CRM). The overall design guarantees robust stability and tracking performance in the presence of parametric uncertainties that are commonly seen in aircraft applications. Supplementary materials for the CDC paper. 2015-09-14T00:00:00Z