Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)


Mechanical and Aerospace Engineering


Amit Sanyal


Geometric Mechanics;Nonlinear Control;Nonlinear Observer;System Constraints

Subject Categories

Aerospace Engineering | Engineering


In the first part of this dissertation, we consider the control of autonomous systems in the presence of pointwise-in-time state and control constraints. Firstly, we propose the attitude and pointing control of a rigid body in the presence of constraints. Artificial potentials are used to achieve desired tracking and avoid pointing direction constraints. The proposed control law ensures the asymptotic convergence to the desired attitude and pointing direction. Additionally, the control of driftless control-affine systems is also considered. The feedback system converges in a stable manner to the desired safe set in the state space, while avoiding the unsafe exclusion zones in the state space and maintaining control input constraints. The problem of constraints satisfaction is then extended to the case where system model is unknown or partially known. The design of reference governors is proposed to the data-driven control of systems with unknown input-output dynamics. The Lyapunov analysis ensure that the output of the reference governor-based control system converges to a desired output trajectory that meets the constraints. In the second part of this dissertation, we consider state estimation on the Lie group of rigid body motions, SE(3). A finite-time stable pose estimation scheme is proposed to provide estimates of the pose from three-dimensional point cloud measurements obtained by a body-mounted optical sensor(s). This observer is designed directly on the Lie group of rigid body motions, SE(3), and is model-free. The proposed Lyapunov analysis shows finite-time stability and its robustness to bounded measurement noises.


Open Access