Sahjendra N. Singh

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This paper presents an approach to large-angle rotationalmaneuvers of a spacecraft-beam-tip body configuration based onnonlinear invertibility and linear feedback stabilization. A controllaw Ud is derived for the decoupled control of attitude angles, lateralelastic deflections, slopes due to bending and angular deflection dueto torsion at the tip of the(More)
In this Letter a feedback linearizing adaptive control system for the control of Chua’s circuits is presented. It is assumed that all the parameters of the system are unknown. Using a backstepping design procedure, an adaptive control system is designed which accomplishes trajectory control of the chosen node voltage by an independent voltage source.(More)
This paper treats the question of control of an elastic robotic arm of two links based on variable structure system (VSS) theory and pole assignment technique for stabilization. A discontinuous joint angle control law, based on VSS theory, is designed which accomplishes asymptotic decoupled joint angle trajectory tracking. In the closed-loop system, the(More)
This paper treats the question of control of a biorobotic autonomous undersea vehicle (BAUV) in the yaw plane using a biomimetic mechanism resembling the pectoral fins of fish. These fins are assumed to undergo a combined sway-yaw motion and the bias angle is treated as a control input, which is varied in time to accomplish the maneuver in the yaw-plane.(More)
The question of realization and feedback linearization of a class of differential-algebraic systems is considered. Based on nonlinear inversion of an input-output map, an analytical expression for the constraint force vector satisfying the algebraic constraints is derived. In this derivation, certain requirements on the relative degree of the output(More)
The development of a non-certainty-equivalent adaptive control system for the control of a nonlinear aeroelastic system is the subject of this paper. The prototypical aeroelastic wing section considered here includes structural nonlinearity and a single control surface for the purpose of control. Its dynamical model has two-degree-of-freedom and describes(More)
Energy efficient, lightweight robot arms for space applications have considerable structural flexibility. We present in this paper an approach to control of a class of flexible robotic systems. A control law is derived which decouples the joint-angle motion from the flexible motion and, in addition, asymptotically decomposes the elastic dynamics into two(More)
The question of control of the end effector trajectory and stabilization of a two-link flexible robotic arm is considered. A control law based on the inversion of an input-output map is obtained. The outputs are chosen as the sum of the joint angle and tip elastic deformation times a constant factor for each link. The stable maneuver of the arm critically(More)
This paper treats the question of servoregulation of autonomous underwater vehicles (AUVs) in the yaw plane using pectoral-like mechanical fins. The fins attached to the vehicle have oscillatory swaying and yawing motion. The bias angle of the angular motion of the fin is used for the purpose of control. Of course, the design approach considered here is(More)
This article introduces a variable structure system scheme to control the end effector trajectory of a two-link flexible robotic arm. Because control of the actual tip position leads to unstable zero dynamics, control of points in the neighborhood of the tip is considered. An output is chosen as the sum of the joint angle and tip elastic deformation times a(More)