Jessica S. Ortiz

Robust Control with Dynamic Compensation for Human-Wheelchair System

This work presents the kinematic and dynamic modeling of a human-wheelchair system, and dynamic control to solve the path following problem. First it is proposed a dynamic modeling of the human-wheelchair system where it is considered that its mass center is not located at the center the wheels’ axle of the wheelchair. Then, the design of the control algorithm is presented. This controller design is based on two cascaded subsystems: a kinematic controller with command saturation, and a dynamic controller that compensates the dynamics of the robot. Stability and robustness are proved by using Lyapunov’s method. Experimental results show a good performance of the proposed controller as proved by the theoretical design.

Adaptive cooperative control of multi-mobile manipulators

This paper presents a multi-layer scheme for the adaptive coordinated cooperative control of n mobile manipulator. 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. Also, the redundancy of the n 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 theory. Simulation results show a good performance of the proposed control scheme as proved by the theoretical design.

Bilateral Control of a Robotic Arm Through Brain Signals

This work presents the design of a bilateral teleoperation system for a robotic arm, allowing people with upper limb impairments to move and manipulate objects through brain signals. The person receives visual feedback from the remote site, and it sends position commands and movement velocity to the slave. The desired velocity of the end-effector is considered as a function of the disregard of the person to move the robotic arm. Additionally, the singular configuration prevention through the systems manipulability control is considered. Finally, the simulation results are reported to verify the performance of the proposed system.

Assistance System for Rehabilitation and Valuation of Motor Skills

This article proposes a non-invasive system to stimulate the rehabilitation of motor skills, both of the upper limbs and lower limbs. The system contemplates two ambiances for human-computer interaction, depending on the type of motor deficiency that the patient possesses, i.e., for patients with chronic injuries, an augmented reality environment is considered, while virtual reality environments are used in people with minor injuries. In the cases mentioned, the interface allows visualizing both the routine of movements performed by the patient and the actual movement executed by him. This information is relevant for the purpose of (i) stimulating the patient during the execution of rehabilitation, and (ii) evaluation of the movements made so that the therapist can diagnose the progress of the patient’s rehabilitation process. The visual environment developed for this type of rehabilitation provides a systematic application in which the user first analyzes and generates the necessary movements in order to complete the defined task. The results show the efficiency of the system generated by the human-computer interaction oriented to the development of motor skills.

Teaching Process for Children with Autism in Virtual Reality Environments

This paper presents the implementation of 3D virtual environments applied to the teaching-learning process for children with autism. The virtual system implemented allows real-time bilateral interaction between the user and the virtual environment in order to stimulate the abilities of children with autism spectrum disorder. The implemented system has multiple environments and applications for interaction with the physical medium in order to increase the stimulus of the affected. The results show the benefit and usability of the implementation of virtual environments to the processes of teaching learning of children with autism.

Modeling Dynamic of the Human-Wheelchair System Applied to NMPC

This paper presents the development of algorithm nonlinear predictive controller based on the model, NMPC, trajectory tracking applied to a wheelchair. Also it illustrated the kinematic and dynamic modeling of human-wheelchair system is considered in which the deviation of the center of gravity of the system due to postural problems of man, limb amputations, or obesity user. In NMPC they considered restrictions on control measures, as well as in the states of the system. The results show that the movements of the wheelchair converge to the desired trajectory in accordance with the provisions of the theoretical design; with analysis times NMPC calculation algorithm concludes that the controller can be implemented in real time.

Realism in Audiovisual Stimuli for Phobias Treatments Through Virtual Environments

This article proposes a system of perception of the real world through audiovisual stimulation for the treatment of different types of phobias. The proposed system is made up of various virtual environments which will be selected according to the phobia to be treated, i.e., the user-environment integration depends on the type and degree of the phobia. The interface allows visualize the environment where the patient must comply with a predetermined therapy by the psychotherapist, in which the biometric signals of the patient are feed back in real time through wearables devices. This information is processed in order to ingest directly in the algorithm of the user’s behavior; algorithm that controls the audiovisual stimuli related to the phobia during the interaction of the virtual environment with the user. In addition, the parameters of the biometric signals are displayed graphically/numerically in the virtual environment in order for the patient to control their behavior and face their irrational fear-phobia. The results are validated based on the realism of the virtual environments developed, and the audio-visual stimuli applied to the patient based on the change of the parameters of the biometric signals acquired through wearable devices.

Modeling and Kinematic Nonlinear Control of Aerial Mobile Manipulators

This work proposes a kinematic modeling and a kinematic nonlinear controller for an autonomous aerial mobile manipulator robot that generates saturated reference velocity commands for trajectory tracking problem. In the kinematic modeling is considered through of a quadcopter-inner-loop system to independently track four velocity commands: forward, lateral, up/downward, and heading rate; and arm-inner-loop system to independently track angular velocity commands. Stability and robustness of the complete control system are proved through the Lyapunov method. Finally, simulation results are presented and discussed, which validate the proposed controller.

Path Planning Based on Visual Feedback Between Terrestrial and Aerial Robots Cooperation

This paper presents an algorithm for path planning in which the evasion of fixed and mobile obstacles is considered in order to be followed by an unmanned land vehicle; path planning is based on visual feedback through an unmanned aerial vehicle. In addition, a path planning algorithm is proposed for the ground vehicle in which a non-constant velocity is considered that is a function of the control error, of the curvature of the road to be followed. The stability of the control algorithm is tested through the Lyapunov method. Finally the experimental results are presented and discussed in which the proposal is validated.

Robotic Applications in Virtual Environments for Children with Autism

In this paper, it proposes the development of a virtual reality system that works simultaneously with the physical environment, by creating an atmosphere that stimulates the abilities of children with autism spectrum disorder. This system is implemented through a human - machine interface, which has the possibility to simulate and work with functions focused on rehabilitation, so the patient will be involved in assisted therapies based on DSM - 5 protocols. Therefore, multiple environments and applications are presented for the interaction with the physical media to increase the stimulus of the affected one. The results of the application are presented to validate the project using the information collected through the interaction between the developer, therapist and patient.