Varela Aldas, José
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Varela Aldas, José
Main Affiliation
Ambato
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josevarela@uti.edu.ec
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Scopus Author ID
57192546163

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Effects of a dual intervention (motor and virtual reality-based cognitive) on cognition in patients with mild cognitive impairment: a single-blind, randomized controlled trial

2024 , Buele, Jorge , Avilés-Castillo, Fátima , Carolina Del-Valle-Soto , Varela Aldas, José , Guillermo Palacios-Navarro

Abstract Background The increase in cases of mild cognitive impairment (MCI) underlines the urgency of finding effective methods to slow its progression. Given the limited effectiveness of current pharmacological options to prevent or treat the early stages of this deterioration, non-pharmacological alternatives are especially relevant. Objective To assess the effectiveness of a cognitive-motor intervention based on immersive virtual reality (VR) that simulates an activity of daily living (ADL) on cognitive functions and its impact on depression and the ability to perform such activities in patients with MCI. Methods Thirty-four older adults (men, women) with MCI were randomized to the experimental group (n = 17; 75.41 ± 5.76) or control (n = 17; 77.35 ± 6.75) group. Both groups received motor training, through aerobic, balance and resistance activities in group. Subsequently, the experimental group received cognitive training based on VR, while the control group received traditional cognitive training. Cognitive functions, depression, and the ability to perform activities of daily living (ADLs) were assessed using the Spanish versions of the Montreal Cognitive Assessment (MoCA-S), the Short Geriatric Depression Scale (SGDS-S), and the of Instrumental Activities of Daily Living (IADL-S) before and after 6-week intervention (a total of twelve 40-minutes sessions). Results Between groups comparison did not reveal significant differences in either cognitive function or geriatric depression. The intragroup effect of cognitive function and geriatric depression was significant in both groups (p < 0.001), with large effect sizes. There was no statistically significant improvement in any of the groups when evaluating their performance in ADLs (control, p = 0.28; experimental, p = 0.46) as expected. The completion rate in the experimental group was higher (82.35%) compared to the control group (70.59%). Likewise, participants in the experimental group reached a higher level of difficulty in the application and needed less time to complete the task at each level. Conclusions The application of a dual intervention, through motor training prior to a cognitive task based on Immersive VR was shown to be a beneficial non-pharmacological strategy to improve cognitive functions and reduce depression in patients with MCI. Similarly, the control group benefited from such dual intervention with statistically significant improvements. Trial registration ClinicalTrials.gov NCT06313931; https://clinicaltrials.gov/study/NCT06313931.

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System Identification and Nonlinear Model Predictive Control with Collision Avoidance Applied in Hexacopters UAVs

2022 , Recalde, Luis , Guevara, B.S. , Carvajal, C.P. , Andaluz, V.H. , Varela Aldas, José , Gandolfo, D.C.

Accurate trajectory tracking is a critical property of unmanned aerial vehicles (UAVs) due to system nonlinearities, under-actuated properties and constraints. Specifically, the use of unmanned rotorcrafts with accuracy trajectory tracking controllers in dynamic environments has the potential to improve the fields of environment monitoring, safety, search and rescue, border surveillance, geology and mining, agriculture industry, and traffic control. Monitoring operations in dynamic environments produce significant complications with respect to accuracy and obstacles in the surrounding environment and, in many cases, it is difficult to perform even with state-of-the-art controllers. This work presents a nonlinear model predictive control (NMPC) with collision avoidance for hexacopters’ trajectory tracking in dynamic environments, as well as shows a comparative study between the accuracies of the Euler–Lagrange formulation and the dynamic mode decomposition (DMD) models in order to find the precise representation of the system dynamics. The proposed controller includes limits on the maneuverability velocities, system dynamics, obstacles and the tracking error in the optimization control problem (OCP). In order to show the good performance of this control proposal, computational simulations and real experiments were carried out using a six rotary-wind unmanned aerial vehicle (hexacopter—DJI MATRICE 600). The experimental results prove the good performance of the predictive scheme and its ability to regenerate the optimal control policy. Simulation results expand the proposed controller in simulating highly dynamic environments that showing the scalability of the controller. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

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Modelling and control of a mobile manipulator for trajectory tracking

2018 , Varela Aldas, José , Andaluz V.H. , Chicaiza F.A.

This article presents the mathematical modelling of a mobile manipulator robot to describe its kinematic and dynamic behaviour; the kinematic model is used to design a control law that allows the autonomous tracking of trajectories in structured spaces; while the dynamic model is used to compensate for speed errors in the robot. Additionally, the stability of the proposed control systems is demonstrated, and finally, simulation and experimentation tests are carried out to validate the proper functioning of the controllers. © 2018 IEEE.

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Robotic cane for the visually impaired

2020 , Varela Aldas, José , Guamán J. , Paredes B. , Chicaiza F.A.

Currently, there is a growing public interest in improving the quality of life of people with disabilities, being the visual limitation one of them, where different research projects have been developed. Assistance robotics is a branch dedicated to the support in mobility and rehabilitation of people with visual disabilities and other limitations. This work describes the construction and use of a robotic cane to assist people with visual problems. The robot structure is generated by 3D printing, and the electronic system has been designed based on Arduino technology. The robot features include a sensor distance to detect possible collisions, a GPS to track its movements, and two DC motors in caterpillar-like configuration for cane mobility. In addition, the robot has connectivity with mobile devices through Bluetooth communication, where the mobile application coordinates the movements of the robot in two ways, manual and autonomous, allowing to reach the desired location and sending the user’s location to the web. This proposal is tested in a structured environment so that patients cast their perspective through a usability test and their characteristics are examined through the analysis of an expert. © Springer Nature Switzerland AG 2020.

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Development of a Scale Prototype of Smart Bed Controlled Using a Mobile Application

2022 , Soberon J.C. , Gamboa G. , Castillo F. , Palacios-Navarro G. , Varela Aldas, José

The need for a technological system for health care for sick people is evident. This work develops a scale prototype of a smart bed controlled through a mobile application. The electronic design consists of two servomotors that act to position the bed; these actions can be activated through the mobile application. At the same time, the patient can be monitored by a camera and an infrared thermometer that sends the data to the application through the Internet. The local operating code is designed so that the position of the bed changes automatically according to a preset sequence. The electronic system is based on the ESP32 board; this chip integrates WiFi communication that allows the connection of the bed with the cloud-based in Firebase. Temperature tests were carried out with the help of people to ensure that the data taken was correct. In addition, bed positions and reception of camera images were tested on a mannequin. As a result, adequate communication was obtained between the mobile application and all the devices installed in the smart bed. Finally, an acceptance test is applied that validates this proposal with a good score. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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Development of Behavior Profile of Users with Visual Impairment

2020 , Guevara Maldonado, César Byron , Arias Flores, Hugo Patricio , Varela Aldas, José , Castillo Salazar, David Ricardo , Borja M. , Fierro-Saltos W. , Rivera R. , Hidalgo-Guijarro J. , Yandún-Velasteguí M.

The interaction of the user with visual impairment with assistive technologies, and in particular with screen readers, generates a group of actions and events during their navigation. These interactions are defined as behavioral patterns, which have a sequence that occurs at specific time slot. Understanding user behavior by analyzing their interaction with applications, in addition, details the characteristics, relationships, structures and functions of the sequence of actions in a specific application domain. The objective of this document is to find activity patterns from a set of commands used by the user, combining data mining and a Bayesian model. This model calculates the probability of the functions used with the screen reader and generates a behavior profile to improve the user experience. For this study, the screen reader JAWS version 2018, the Open Journal Systems platform version 3.0.1 and a computer with Windows 10 operating system were used. During the first phase, command history used by the user by interacting with the Open Journal Systems platform were collected. The result is that the accessibility of users with visual impairment to interact with the computer and its applications has been improved by applying this model. © Springer Nature Switzerland AG 2020.

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Temperature control system with hysteresis for drying oven using IoT

2023 , Bucay-Valdiviezo J. , Veronica-Ocana Parra S. , Saa F. , Varela Aldas, José

The fourth industrial revolution (Industry 4.0) spread to the whole world, improving all kinds of industrial processes. Thus, temperature control and monitoring of ovens through the Internet of Things (IoT) is part of this technology, especially in the automotive industry. In this work, the temperature control with hysteresis of a drying oven is carried out incorporating the IoT, with the objective of maintaining the temperature within a certain range in the drying process inside an oven. For this, a thermocouple, heat lamps, couplers and an electronic board are used. The temperature data from the drying oven is sent to the internet via WiFi using a router. The oven temperature data is recorded in the cloud for its respective subsequent analysis using the ThingSpeak services. For the results, the temperature is configured in the range of 50 ° C to 70 ° C that is monitored through a mobile application developed in App Inventor. The tests carried out demonstrate the proper functioning of the system and the high usability of the application. © 2023 IEEE.

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Body Temperature Control Using a Robotic Arm

2021 , Varela Aldas, José , Moreira A. , Criollo P. , Ruales, María Belén

At the end of 2019, a highly contagious virus appears, changing the form of interaction between humans, this has implied the use of technology as a support tool to counteract the effects of the new disease (COVID-19). Although many technologies have been successfully adapted, applied robotics promises to reduce or even eliminate the need for person-to-person contact. This article presents the control of the body temperature of the clients of a commercial premises through the implementation of a system that includes a robotic arm, two sensors and a mobile device. The robotic arm is constructed using 3D printing and a low-cost electronic circuitry, body temperature is obtained using an infrared sensor, and a mobile device displays, alerts, and stores the information. The developed code allows remote control of the robot positions or a pre-programmed sequence is automatically activated that includes temperature measurement and hand disinfection. The results show the robot in operation and the data acquired by the system, observing adequate temperatures in most of the users and a single alert during the tests carried out. The conclusions establish the importance of the system in the real application and highlight the multiple benefits of this proposal. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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Salty Taste Intensity Classifier Through Multivariate Analysis

2022 , Fuentes E.M. , Varela Aldas, José , Verdú S. , Grau Meló R. , Barat J.M. , Alcañiz M.

Voltammetric electronic Tongues (VET) are widely used on the industry, especially when focused on sample classification, adulteration recognizement and quality control, a VET equipment developed by the Interuniversity Institute of Molecular Recognition and Technological Development of the UPV-UV (IDM) was employed to develop the study, the results of each test were 7920 data, and different Chloride of Sodium concentrations such as 1.25 mM, 2.5 mM, 5 mM and 10 mM were tested. This is a part of a series of studies related with basic flavor recognize though VET, so the aim of this work was to study the capability of the VET to recognize different intensity of salt concentrations, supported on multivariate analysis. The results showed a concordance of more than 70.31% in the separation of samples, allowing to conclude as acceptable the performance of the classifier and the data acquired through the voltammetric electronic tongues. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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IoT-Based User Interface for Remote Control of a Mobile Robot

2023 , Varela Aldas, José , Palacios-Navarro G.

Recent advancements in mobile robot research have resulted in the development of precise robot control tools, while information technology research has focused on the Internet of Things (IoT) in the context of the fourth industrial revolution. This study evaluates a user interface designed for remote control of the Crowbot BOLT robot. This robot utilizes the ESP32 board and is controlled through the M5Stack Core2 kit with a touch screen. The user interface offers two modes of operation: touch-based buttons for movement control and gyroscope control based on the M5Stack’s angular position. Communication between the robot and the user interface is established using the MQTT protocol through the ThingSpeak server, allowing control from any location with a line of sight and internet connectivity. Operation data is collected by recording control orders and measuring sending times, while user acceptance is evaluated using an IoT-based technology acceptance model. The results indicate the need for remote control response time improvement and reveal low scores in perceived usefulness and influence social. In conclusion, the study demonstrates the feasibility of remote control of a mobile robot using the MQTT protocol, providing valuable insights for similar applications and considering user recommendations for future enhancements and system expansion. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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