In this paper is presented a new technique to design trajectories with finite time convergence properties for precision tracking maneuvers in unmanned vehicles. This technique allows the finite time positioning on sequentially distributed points, the properties for the trajectory guarantee to start in an initial point with velocity and acceleration zero, and position itself on the subsequent point with finite time convergence, again with velocity and acceleration zero. Such trajectory depends exclusively of the time and of the initial and last position. In addition, this technique could be used to design open loop controllers to be implemented in mobile robotics applications that require long accuracy. To show the controllers feasibility we considering the kinematic car model with finite time properties, obtaining an open loop control for the car’s velocity and steering the vehicle to desired trajectory, where simulation results present the control performance and effectiveness.
In this work, the analysis of the dynamic general model of an unmanned underwater vehicle (UUV) based on dual quaternions is presented, then the general dynamic model is reduced to a specific vehicle of 4 DoF, this model eliminates the singularities that exist with the representation of the Euler angle and that the model is more compact than others proposed in the literature [1],[2]. To demonstrate the applicability of the model, three controller strategies are proposed for tracking a trajectory, the first controller is a PD + G, under unknown disturbances it produces a considerable tracking error, the second is an adaptive controller that estimates unknown hydrodynamic parameters, and the third is a robust controller for unknown disturbances and parameter uncertainties. The closed-loop system stability analysis for each controller is based on Lyapunov’s theory, a set of numerical simulations is performedto show the behavior of the vehicle with the proposed controllers. The efficiency of the controllers is shown in Table 2 where it is deduced that the adaptive controller has a better performance. The graphics show that the robust controller has little error tracking and the computational cost is lower.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.