Examinando por Autor "Rodriguez-Barroso, Alejandro"

Mostrando 1 - 6 de 6

A Sensor Based on a Spherical Parallel Mechanism for the Measurement of Fluid Velocity: Experimental Development
(IEEE, 2019-02-01) Portilla, Gerardo; Saltaren, Roque; Rodriguez-Barroso, Alejandro; Cely, Juan S.; Yakrangi, Oz
In this paper, an experimental demonstration was developed, to measure the velocity of a fluid by using a sensor based on the spherical parallel mechanism with three degrees-of-freedom. This sensor transforms the kinetic energy of the fluid into potential energy by deforming the parallel mechanism. This deformation is due to the impact of the fluid on a sphere attached to the platform of the parallel mechanism. Through the acquisition of data from an inertial measurement unit in the sphere, an algorithm calculates the velocity and direction of the fluid. The mathematic model and algorithm of the velocity measurement was developed in a previous article. This paper built and tested the sensor with the objective of demonstrating the theoretical basis for the sensor. The experiment is based on the underwater movement of the sensor in a linear way along a rail. The velocity that is measured by the linear encoder is equal to the fluid's relative velocity that is measured by the sensor. The measurements taken by the encoder and the sensor were compared in three experiments. The results show that the two measurements were similar, demonstrating that the sensor can accurately measure the velocity of the fluid.
An Intelligent Algorithm for Decision Making System and Control of the GEMMA Guide Paradigm Using the Fuzzy Petri Nets Approach
(MDPI, 2021-02-19) Yakrangi, Oz; Saltaren, Roque; Cely, Juan S.; Rodriguez-Barroso, Alejandro; Garcia Cena, Cecilia E.; San Segundo, Pablo; De la Cueva, Julio; Shapiro, Amir
The aim of this article is to present the fuzzy Petri net algorithm and its implementation on the Guide d’etude des modes de marche et d’arrêt (GEMMA) guide paradigm. Additionally, this article presents a brief description of the GEMMA guide paradigm, the fuzzy logic approach, the Petri nets theory, and fuzzy Petri nets. Each algorithm is intended for a specific set of transitions, depending on their essential conditions. All these algorithms generate intelligent and safe control of the GEMMA guide paradigm in order to have the best control system for the machine. Moreover, the algorithms are able to make the best decision automatically depending on the machine’s situation and condition, something that allows the machine to be placed in the appropriate mode for each situation. The results show that the different fuzzy Petri net algorithms were working properly for the GEMMA guide paradigm and provided a proper solution for the automation of production systems.
Cable-Driven Parallel Robot with Reconfigurable End Effector Controlled with a Compliant Actuator
(MDPI, 2018-08-22) Rodriguez-Barroso, Alejandro; Saltaren, Roque; Portilla, Gerardo; Cely, Juan S.; Carpio, Marco
Redundancy in cable-driven parallel robots provides additional degrees of freedom that can be used to achieve different objectives. In this robot, this degree of freedom is used to act on a reconfigurable end effector with one degree of freedom. A compliant actuator actuated by one motor exerts force on both bodies of the platform. Due to the high tension that appears in this cable in comparison with the rest of the cables, an elastic model was developed for solving the kinestostatic and wrench analysis. A linear sensor was used in one branch of this cable mechanism to provide the needed intermediate values. The position of one link of the platform was fixed in order to focus this analysis on the relationship between the cables and the platform’s internal movement. Position values of the reconfigurable end effector were calculated and measured as well as the tension at different regions of the compliant actuator. The theoretical values were compared with dynamic simulations and real prototype results.
Dynamic Walking of a Legged Robot in Underwater Environments Environments
(MDPI, 2019-08-17) Portilla, Gerardo; Saltaren, Roque; Montero de Espinosa, Francisco; Rodriguez-Barroso, Alejandro; Cely, Juan S.; Yakrangi, Oz
In this research, the dynamic walking of a legged robot in underwater environments is proposed. For this goal, the underwater zero moment point (Uzmp) is proposed in order to generate the trajectory of the centre of the mass of the robot. Also, the underwater zero moment point auxiliary (Uzmp aux.) is employed to stabilize the balance of the robot before it undergoes any external perturbations. The concept demonstration of a legged robot with hydraulic actuators is developed. Moreover, the control that was used is described and the hydrodynamic variables of the robot are determined. The results demonstrate the validity of the concepts that are proposed in this article, and the dynamic walking of the legged robot in an underwater environment is successfully demonstrated.
Experimental and Computational Methodology for the Determination of Hydrodynamic Coefficients Based on Free Decay Test: Application to Conception and Control of Underwater Robots
(MDPI, 2019-08-21) Cely, Juan S.; Saltaren, Roque; Portilla, Gerardo; Yakrangi, Oz; Rodriguez-Barroso, Alejandro
Hydrodynamic coefficients are essential for the development of underwater robots; in particular, for their design and navigation control. To obtain these coefficients, several techniques exist. These methods are usually experimental, but, more recently, some have been designed by a combination of experiments with computational methods based on Computational Fluid Dynamics (CFD). One method for obtaining the hydrodynamic coefficients of an ROV (Remote Operated Vehicle) is by using an experimental PMM (Planar Motion Mechanism) or CWC (Circular Water Channel); however, the use of these experimental infrastructures is costly. Therefore, it is of interest to obtain these coefficients in other ways, for example, by the use of simple experiments. The Free Decay Test is an ideal type of experiment, as it has a low cost and is simple to implement. In this paper, two different free decay tests were carried out, to which three different methods for obtaining coefficients were applied. They were compared with results obtained by CFD simulation to conduct a statistical analysis in order to determine their behaviours. It was possible to obtain values of the drag and added mass coefficients for the models analysed, where the values were obtained for an Underwater Drone Robot (UDrobot).
Potential Energy Distribution of Redundant Cable-Driven Robot Applied to Compliant Grippers: Method and Computational Analysis
(MDPI, 2019-08-02) Rodriguez-Barroso, Alejandro; Saltaren, Roque; Portilla, Gerardo; Cely, Juan S.; Yakrangi, Oz
Cable-driven parallel robots with a redundant configuration have infinite solutions for their cable tension distribution to provide a specific wrench to the end-effector. Redundancy is commonly used to increase the workspace and stiffness or to achieve secondary objectives like energetic minimization or additional movements. This article presents a method based on energy distribution to handle the redundancy of cable-driven parallel robots. This method allows the deformation and tension of each link to be related to the total energy available in the parallel robot. The study of energy distribution expression allows deformation, tension, and position to be combined. It also defines the range of tension and deformation that cables can achieve without altering the wrench exerted on the end-effector. This range is used with a passive reconfigurable end-effector to control the position of two grippers attached to some cables which act as compliant actuators. The relationship between the actuators’ energy and their corresponding gripper positions is also provided. In this way, energy measurement from the actuators allows the grasping state to be sensed. The results are validated using multibody dynamic software.