Loading...
Search for:
pseudospectral
0.007 seconds
Pseudospectral optimal control of active magnetic bearing systems
, Article Scientia Iranica ; Vol. 21, Issue. 5 , 2014 , pp. 1719-1725 ; ISSN: 10263098 ; Livani, M ; Sharif University of Technology
Abstract
In this paper, an optimal control framework is formed to control rotor-Active Magnetic Bearing (AMB) systems. The multi-input-multi-output non-affine model of AMBs is well established in the literature and represents a challenging problem for control design, where the design requirement is to keep the rotor at the bearing centre in the presence of external disturbances. To satisfy the constraints on the states and the control inputs of the AMB nonlinear dynamics, a nonlinear optimal controller is formed to minimize tracking error between the current and desired position of the rotor. To solve the resulted nonlinear constrained optimal control problem, the Gauss Pseudospectral Collocation...
Optimal tracking control of an underactuated container ship based on direct Gauss Pseudospectral Method
, Article Scientia Iranica ; Vol. 21, issue. 6 , 2014 ; Salarieh, H ; Sharif University of Technology
Abstract
In this paper, the problem of optimal tracking control for a container ship is addressed. The multi-input-multi-output nonlinear model of the S175 container ship is well established in the literature and represents a challenging problem for control design, where the design requirement is to follow a commanded maneuver at a desired speed. To satisfy the constraints on the states and the control inputs of the vessel nonlinear dynamics and minimize the heading error, a nonlinear optimal controller is formed. To solve the resulted nonlinear constrained optimal control problem, the Gauss Pseudospectral Method (GPM) is used to transcribe the optimal control problem into a Nonlinear Programming...
Path Planning and Design of Optimal Guidance Algorithm for a High Speed Planing Craft
, M.Sc. Thesis Sharif University of Technology ; Salarieh, Hassan (Supervisor)
Abstract
In this thesis, the problem of trajectory planning for a high speed planing boat under nonlinear equality and inequality constraints is addressed. First, a nonlinear mathematical model of the craft’s dynamics is derived. To solve a trajectory optimization problem, we can utilize the indirect or direct methods. In the indirect methods, maximum principle of Pontryagin is used to transform the optimal control problem into Euler Lagrange equations, on the other hand, in the direct methods it is necessary to transcribe the optimal control problem into a nonlinear programming problem (NLP) by discretization of states and controls. The resulted NLP can be solved by well-developed algorithms such as...
Development of an Optimal Path Planning Algorithm for Aerial Robots Based on GPOPS Program
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
In this thesis the problem of path planning for aerial robots,specifically the UAVs, is studied. Some software packs aiming to perform optimal path planning are already published worldwide. In this thesis, these software are investigated and UAV path planning is done by them. In UAV path planning using these software, due to the high number of equations, number of constraints in solution increases and even in a simple problem, the process of solving becomes difficult for software. Among introduced software packs, “GPOPS”, which uses pseudospectral methods, is chosen as the best. Avoiding obstacles in different problems is checked. Obstacle avoidance and waypoint tracking at the same time,...
Optimal Coupled Rendezvous and Docking Control
, M.Sc. Thesis Sharif University of Technology ; Pourtakdoust, Hassan (Supervisor)
Abstract
Planning safe rendezvous and docking trajectories between two spacecrafts has a high importance in the space applications. In order to make two spacecrafts moving in different orbits closer, two stages must be completed simultaneously: First the implementation of rendezvous maneuver which deals with the generation of control/guidance commands leading to trajectories that lead the chaser towards the target. Second the docking maneuver incorporation which makes the two spacecrafts closer with the relative zero attitude. Various approaches have been dealt with till now using the analytical and numerical approaches generally considering rendezvous, not the docking maneuver. These approaches...