Andrés Rosales

A fixed-frequency Sliding-mode control in a cascade scheme for the Half-bridge Bidirectional DC-DC converter

For the Half-bridge Bidirectional DC-DC power converter focused on electric traction applications, this paper develops a fixed-frequency Sliding-mode control (SMC) based on a cascade structure. First, the use of cascade control is justified by means of the state space small-signal averaged equations. Then, the design of the proposed cascade SMC scheme is detailed. Lastly, the simulation results showed that the developed control strategy outperforms the sole use of SMC for different comparison scenarios.

Multilayer scheme for the adaptive cooperative coordinated control of mobile manipulators

This paper presents a multi-layer scheme for the adaptive cooperative coordinated control of mobile manipulator robots. Each layer works as an independent module, dealing with a specific part of the problem of cooperation, coordination and adaptation, thus giving more flexibility to the scheme. The adaptive dynamic compensation layer is capable of updating the estimated parameters for all robots, which are directly related to physical parameters of each mobile manipulator. Also, the redundancy of the mobile manipulators is used for the avoidance of obstacles by the mobile platforms - without deforming the virtual structure and maintaining its desired trajectory - and the singular configuration prevention through the systems manipulability control. Stability and robustness are proved by using Lyapunovs method. Simulation results show a good performance of the proposed multi-layer scheme as proved by the theoretical design.

A dynamical sliding mode control approach for long deadtime systems

The purpose of this work is to combine the concepts of sliding mode control and internal model control to design a Dynamical Sliding Mode Control (DMSC). The Internal Model Control (IMC) structure is used to obtain a simple and easy way to design the controller. This new approach eliminates the major sliding mode control problem: chattering. The process is reduced to a first-order-plus-deadtime (FOPDT) model, and it is divided in two components an invertible one and other non-invertible. A lead term is added to the invertible term and a lead-lag model is obtained and used to get the desired controller. The approach is tested in a high order system with elevated deadtime. The performance of the controller is tested under tracking and regulation conditions: change in the set point, persistent disturbance applied at a determined time, and addition of noise. Finally, a robustness test is conducted to prove how well the controller works when the plant ages. In every of these cases, the performance of the controller is satisfactory, also neither chattering nor instabilities are presented.

A new approach of a Numerical Methods Controller for self-regulating processes

The aim of this paper is to design a Numerical Methods Controller (NMCr) based on a first order plus dead time (FOPDT) model of the actual process. The overall idea is to develop a general NMCr, which can be used for different self-regulating industrial processes, if they have a similar open loop response, such as an FOPDT model. Hence, this work summarises the easily and simplicity of numerical methods procedures along to a reduced order model of the process to obtain a simple and versatile controller. The performance of the proposed controller in this article is tested by simulations in several higher order linear systems with different characteristics. It is compared against a PID, and also its robustness is checked.