Development of a Low-Cost Markerless Optical Motion Capture System for Gait Analysis and Anthropometric Parameter Quantification.

Technological advancements have expanded the range of methods for capturing human body motion, including solutions involving inertial sensors (IMUs) and optical alternatives. However, the rising complexity and costs associated with commercial solutions have prompted the exploration of more cost-effective alternatives. This paper presents a markerless optical motion capture system using a RealSense depth camera and intelligent computer vision algorithms. It facilitates precise posture assessment, the real-time calculation of joint angles, and acquisition of subject-specific anthropometric data for gait analysis. The proposed system stands out for its simplicity and affordability in comparison to complex commercial solutions. The gathered data are stored in comma-separated value (CSV) files, simplifying subsequent analysis and data mining. Preliminary tests, conducted in controlled laboratory environments and employing a commercial MEMS-IMU system as a reference, revealed a maximum relative error of 7.6% in anthropometric measurements, with a maximum absolute error of 4.67 cm at average height. Stride length measurements showed a maximum relative error of 11.2%. Static joint angle tests had a maximum average error of 10.2%, while dynamic joint angle tests showed a maximum average error of 9.06%. The proposed optical system offers sufficient accuracy for potential application in areas such as rehabilitation, sports analysis, and entertainment.

Optical fiber sensors for posture monitoring, ulcer detection and control in a wheelchair: a state-of-the-art.

BACKGROUND: In the last ten years, the design and implementation of Optical Fiber Sensors (OFS) in biomedical applications have been discussed, with a focus on different subareas, such as body parameter monitoring and control of assistive devices. MATERIALS AND METHODS: A scoping review was performed including scientific literature (PubMed/Scopus, IEEE and Web of Science), patents (WIPO/Google Scholar), and commercial information. RESULTS: The main applications of OFS in the rehabilitation field for preventing future postural diseases and applying them in device controllers were discussed in this review. Physical characteristics of OFS, different uses, and applications of Polymer Optical Fiber pressure sensors are mentioned. The main postures used for posture monitoring analysis when the user is sitting are normal position, crooked back, high lumbar pressure, sitting on the edge of the chair, and crooked back, left position, and right position. Additionally, it is possible to use Machine Learning (ML) algorithms for posture classification, and device control such as Support Vector Machine, k-Nearest Neighbors, etc., obtaining accuracies above 97%. Moreover, the literature mentions wheelchair controllers and Graphical User Interfaces using pressure maps to provide feedback to the user. CONCLUSIONS: OFS have been used in several healthcare applications as well as postural and preventive applications. The literature showed an effort to implement and design accessible devices for people with disabilities and people with specific diseases. Alternatively, ML algorithms are widely used in this direction, leaving the door open for further studies that allow the application of real-time systems for posture monitoring and wheelchairs control.

IMPLICATIONS FOR REHABILITATIONPosture monitoring and ulcer detection systems are very useful to prevent or treat diseases related to bedsores or pressure ulcers using a different kind of electronic or optic instrumentation to improve the user's quality of life.The system characteristics using optical fiber sensors discussed in this review set an important precedent in the fabrication of low-cost systems for biomedical applications.

A Kinematic Information Acquisition Model That Uses Digital Signals from an Inertial and Magnetic Motion Capture System.

This paper presents a model that enables the transformation of digital signals generated by an inertial and magnetic motion capture system into kinematic information. First, the operation and data generated by the used inertial and magnetic system are described. Subsequently, the five stages of the proposed model are described, concluding with its implementation in a virtual environment to display the kinematic information. Finally, the applied tests are presented to evaluate the performance of the model through the execution of four exercises on the upper limb: flexion and extension of the elbow, and pronation and supination of the forearm. The results show a mean squared error of 3.82° in elbow flexion-extension movements and 3.46° in forearm pronation-supination movements. The results were obtained by comparing the inertial and magnetic system versus an optical motion capture system, allowing for the identification of the usability and functionality of the proposed model.

Assessment of the Mechanical Support Characteristics of a Light and Wearable Robotic Exoskeleton Prototype Applied to Upper Limb Rehabilitation.

Robotic exoskeletons are active devices that assist or counteract the movements of the body limbs in a variety of tasks, including in industrial environments or rehabilitation processes. With the introduction of textile and soft materials in these devices, the effective motion transmission, mechanical support of the limbs, and resistance to physical disturbances are some of the most desirable structural features. This paper proposes an evaluation protocol and assesses the mechanical support properties of a servo-controlled robotic exoskeleton prototype for rehabilitation in upper limbs. Since this prototype was built from soft materials, it is necessary to evaluate the mechanical behavior in the areas that support the arm. Some of the rehabilitation-supporting movements such as elbow flexion and extension, as well as increased muscle tone (spasticity), are emulated. Measurements are taken using the reference supplied to the system's control stage and then compared with an external high-precision optical tracking system. As a result, it is evidenced that the use of soft materials provides satisfactory outcomes in the motion transfer and support to the limb. In addition, this study lays the groundwork for a future assessment of the prototype in a controlled laboratory environment using human test subjects.

Integration of Inertial Sensors in a Lower Limb Robotic Exoskeleton.

Motion assistance exoskeletons are designed to support the joint movement of people who perform repetitive tasks that cause damage to their health. To guarantee motion accompaniment, the integration between sensors and actuators should ensure a near-zero delay between the signal acquisition and the actuator response. This study presents the integration of a platform based on Imocap-GIS inertial sensors, with a motion assistance exoskeleton that generates joint movement by means of Maxon motors and Harmonic drive reducers, where a near zero-lag is required for the gait accompaniment to be correct. The Imocap-GIS sensors acquire positional data from the user's lower limbs and send the information through the UDP protocol to the CompactRio system, which constitutes a high-performance controller. These data are processed by the card and subsequently a control signal is sent to the motors that move the exoskeleton joints. Simulations of the proposed controller performance were conducted. The experimental results show that the motion accompaniment exhibits a delay of between 20 and 30 ms, and consequently, it may be stated that the integration between the exoskeleton and the sensors achieves a high efficiency. In this work, the integration between inertial sensors and an exoskeleton prototype has been proposed, where it is evident that the integration met the initial objective. In addition, the integration between the exoskeleton and IMOCAP is among the highest efficiency ranges of similar systems that are currently being developed, and the response lag that was obtained could be improved by means of the incorporation of complementary systems.

Wheelchair prototype controlled by position, speed and orientation using head movement.

A prototype that simulates a wheelchair was built using electronic commercial devices and software implementation with the aim to operate the prototype using head movement and analyzing the system response. The controllers were simulated using MATLAB® toolbox and Python™ libraries. The mean time response of the system with manual control was 37,8 s. The mean orientation control response with constant speed was 36,5 s and the mean orientation control response with variable speed was 44,2 s in a specific route. The variable speed response is slower than constant speed due to head motion error. The system was rated such as" very good" by 10 participants using a System Usability Scale (SUS).

Integration and Testing of a High-Torque Servo-Driven Joint and Its Electronic Controller with Application in a Prototype Upper Limb Exoskeleton.

Mechatronic systems that allow motorized activation in robotic exoskeletons have evolved according to their specific applications and the characteristics of the actuation system, including parameters such as size, mechanical properties, efficiency, and power draw. Additionally, different control strategies and methods could be implemented in various electronic devices to improve the performance and usability of these devices, which is desirable in any application. This paper proposes the integration and testing of a high-torque, servo-driven joint and its electronic controller, exposing its use in a robotic exoskeleton prototype as a case study. Following a brief background review, the development and implementation of the proposal are presented, allowing the control of the servo-driven joint in terms of torque, rotational velocity, and position through a straightforward, closed-loop control architecture. Additionally, the stability and performance of the servo-driven joint were assessed with and without load. In conclusion and based on the obtained results, the servo-driven joint and its control system demonstrate consistent performance under the proposed test protocol (max values: angular velocity 97 °/s, torque 33 Nm, positioning RMSE 1.46°), enabling this approach for use in various applications related to robotic exoskeletons, including human performance enhancement, rehabilitation, or support for daily living activities.

Design, Development, and Testing of an Intelligent Wearable Robotic Exoskeleton Prototype for Upper Limb Rehabilitation.

Neuromotor rehabilitation and recovery of upper limb functions are essential to improve the life quality of patients who have suffered injuries or have pathological sequels, where it is desirable to enhance the development of activities of daily living (ADLs). Modern approaches such as robotic-assisted rehabilitation provide decisive factors for effective motor recovery, such as objective assessment of the progress of the patient and the potential for the implementation of personalized training plans. This paper focuses on the design, development, and preliminary testing of a wearable robotic exoskeleton prototype with autonomous Artificial Intelligence-based control, processing, and safety algorithms that are fully embedded in the device. The proposed exoskeleton is a 1-DoF system that allows flexion-extension at the elbow joint, where the chosen materials render it compact. Different operation modes are supported by a hierarchical control strategy, allowing operation in autonomous mode, remote control mode, or in a leader-follower mode. Laboratory tests validate the proper operation of the integrated technologies, highlighting a low latency and reasonable accuracy. The experimental result shows that the device can be suitable for use in providing support for diagnostic and rehabilitation processes of neuromotor functions, although optimizations and rigorous clinical validation are required beforehand.

Design and Implementation of a Position, Speed and Orientation Fuzzy Controller Using a Motion Capture System to Operate a Wheelchair Prototype.

The design and implementation of an electronic system that involves head movements to operate a prototype that can simulate future movements of a wheelchair was developed here. The controller design collects head-movements data through a MEMS sensor-based motion capture system. The research was divided into four stages: First, the instrumentation of the system using hardware and software; second, the mathematical modeling using the theory of dynamic systems; third, the automatic control of position, speed, and orientation with constant and variable speed; finally, system verification using both an electronic controller test protocol and user experience. The system involved a graphical interface for the user to interact with it by executing all the controllers in real time. Through the System Usability Scale (SUS), a score of 78 out of 100 points was obtained from the qualification of 10 users who validated the system, giving a connotation of "very good". Users accepted the system with the recommendation to improve safety by using laser sensors instead of ultrasonic range modules to enhance obstacle detection.

Brain-Computer Interfaces Systems for Upper and Lower Limb Rehabilitation: A Systematic Review.

In recent years, various studies have demonstrated the potential of electroencephalographic (EEG) signals for the development of brain-computer interfaces (BCIs) in the rehabilitation of human limbs. This article is a systematic review of the state of the art and opportunities in the development of BCIs for the rehabilitation of upper and lower limbs of the human body. The systematic review was conducted in databases considering using EEG signals, interface proposals to rehabilitate upper/lower limbs using motor intention or movement assistance and utilizing virtual environments in feedback. Studies that did not specify which processing system was used were excluded. Analyses of the design processing or reviews were excluded as well. It was identified that 11 corresponded to applications to rehabilitate upper limbs, six to lower limbs, and one to both. Likewise, six combined visual/auditory feedback, two haptic/visual, and two visual/auditory/haptic. In addition, four had fully immersive virtual reality (VR), three semi-immersive VR, and 11 non-immersive VR. In summary, the studies have demonstrated that using EEG signals, and user feedback offer benefits including cost, effectiveness, better training, user motivation and there is a need to continue developing interfaces that are accessible to users, and that integrate feedback techniques.

Artificial Intelligence-Based Wearable Robotic Exoskeletons for Upper Limb Rehabilitation: A Review.

Processing and control systems based on artificial intelligence (AI) have progressively improved mobile robotic exoskeletons used in upper-limb motor rehabilitation. This systematic review presents the advances and trends of those technologies. A literature search was performed in Scopus, IEEE Xplore, Web of Science, and PubMed using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology with three main inclusion criteria: (a) motor or neuromotor rehabilitation for upper limbs, (b) mobile robotic exoskeletons, and (c) AI. The period under investigation spanned from 2016 to 2020, resulting in 30 articles that met the criteria. The literature showed the use of artificial neural networks (40%), adaptive algorithms (20%), and other mixed AI techniques (40%). Additionally, it was found that in only 16% of the articles, developments focused on neuromotor rehabilitation. The main trend in the research is the development of wearable robotic exoskeletons (53%) and the fusion of data collected from multiple sensors that enrich the training of intelligent algorithms. There is a latent need to develop more reliable systems through clinical validation and improvement of technical characteristics, such as weight/dimensions of devices, in order to have positive impacts on the rehabilitation process and improve the interactions among patients, teams of health professionals, and technology.

Control Systems and Electronic Instrumentation Applied to Autonomy in Wheelchair Mobility: The State of the Art.

Automatic wheelchairs have evolved in terms of instrumentation and control, solving the mobility problems of people with physical disabilities. With this work it is intended to establish the background of the instrumentation and control methods of automatic wheelchairs and prototypes, as well as a classification in each category. To this end a search of specialised databases was carried out for articles published between 2012 and 2019. Out of these, 97 documents were selected based on the inclusion and exclusion criteria. The following categories were proposed for these articles: (a) wheelchair instrumentation and control methods, among which there are systems that implement micro-electromechanical sensors (MEMS), surface electromyography (sEMG), electrooculography (EOG), electroencephalography (EEG), and voice recognition systems; (b) wheelchair instrumentation, among which are found obstacle detection systems, artificial vision (image and video), as well as navigation systems (GPS and GSM). The results found in this review tend towards the use of EEG signals, head movements, voice commands, and algorithms to avoid obstacles. The most used techniques involve the use of a classic control and thresholding to move the wheelchair. In addition, the discussion was mainly based on the characteristics of the user and the types of control. To conclude, the articles exhibited the existing limitations and possible solutions in their designs, as well as informing the physically disabled community about the technological developments in this field.

Upper Limb Physical Rehabilitation Using Serious Videogames and Motion Capture Systems: A Systematic Review.

The use of videogames and motion capture systems in rehabilitation contributes to the recovery of the patient. This systematic review aimed to explore the works related to these technologies. The PRISMA method (Preferred Reporting Items for Systematic reviews and Meta-Analyses) was used to search the databases Scopus, PubMed, IEEE Xplore, and Web of Science, taking into consideration four aspects: physical rehabilitation, the use of videogames, motion capture technologies, and upper limb rehabilitation. The literature selection was limited to open access works published between 2015 and 2020, obtaining 19 articles that met the inclusion criteria. The works reported the use of inertial measurement units (37%), a Kinect sensor (48%), and other technologies (15%). It was identified that 26% used commercial products, while 74% were developed independently. Another finding was that 47% of the works focus on post-stroke motor recovery. Finally, diverse studies sought to support physical rehabilitation using motion capture systems incorporating inertial units, which offer precision and accessibility at a low cost. There is a clear need to continue generating proposals that confront the challenges of rehabilitation with technologies which offer precision and healthcare coverage, and which, additionally, integrate elements that foster the patient's motivation and participation.

Infraestructura física para laboratorios en el área de ingeniería del software / Infraestrutura física para laboratórios na área de engenharia de software / Physical infrastructure for laboratories of the area of software engineering

Resumen Se presenta una propuesta del diseño de infraestructura física con los requerimientos mínimos necesarios para la construcción de un laboratorio que se adapte y facilite el desarrollo e implementación de estrategias de enseñanza y aprendizaje en las asignaturas de Ingeniería de requisitos y Gestión de proyectos informáticos del programa de Ingeniería de Sistemas y Computación de la Universidad Pedagógica y Tecnológica de Colombia (UPTC); dicha propuesta surge a partir de la aplicación y validación de estrategias metodológicas basadas en los niveles de la taxonomía de Bloom, como también en los lineamientos definidos por la guía de conocimientos de ingeniería de software Swebok; por tal razón el artículo presenta el resultado de la investigación que conllevó a esta propuesta donde se proponen el diseño y las características principales de los espacios requeridos para el desarrollo de las actividades propias de la ingeniería de software en las asignaturas mencionadas, es así que se detalla una sala principal, sala de juntas y sala de entrevistas.

Abstract It presents a proposal for the design of physical infrastructure with the minimum requirements necessary for the construction of a laboratory that adapts to the development of the subjects of Requirements Engineering and Management of computer projects of the program of Systems Engineering and Computing of the Universidad Pedagógica y Tecnológica de Colombia (UPTC), this proposal arose from the validation of teaching and learning strategies based on the levels of Bloom's taxonomy and the guidelines defined by the Swebok Software Engineering Knowledge Guide. In such a reason the article presents the design and characteristics of the main spaces for the development of the activities of software engineering in the subjects mentioned, so the main room, meeting room, and interview room are detailed.

Resumo Uma infraestrutura física projeto proposta com os requisitos mínimos para a construção de um laboratório que atende e facilitar o desenvolvimento e implementação de estratégias de ensino e aprendizagem nas disciplinas de Engenharia de Requisitos e programa de gerenciamento de projeto de TI é apresentado Engenharia de sistemas e Computação Pedagógico e Universidad Pedagógica y Tecnológica de Colombia (UPTC); Esta proposta decorre da aplicação e validação com base em níveis de taxonomia de Bloom, bem como nas orientações definidas pelo guia de estratégias metodológicas conhecimento software de engenharia SWEBOK; Por esta razão, o artigo apresenta os resultados do inquérito que conduziu a esta proposta, onde as características do projeto e principais dos espaços necessários para o desenvolvimento da engenharia próprio software nas disciplinas mencionadas actividades são propostas, de modo que detalha um salão principal, sala de reuniões e sala de entrevista.

Modelos de calidad del software, un estado del arte

Existen diferentes modelos de calidad del software que permiten un proceso de mejora continua con su implementación. En el presente escrito se exponen características de los modelos investigados a través de una revisión de información, se realiza una clasificación de los mismos de acuerdo con el nivel de proceso o de producto; cada modelo cuenta con unas características y una estructura la cual se enuncia brevemente en el escrito. Las diferentes empresas, con el fin de verse inmersas en una mejora continua de sus procesos, han identificado la importancia de hacerse a la implementación de modelos que permitan certificar y garantizar la calidad de sus productos y procesos, se encontraron algunos casos de éxito de la implementación de los modelos estudiados, los cuales permitieron a las empresas posicionarse o destacarse por mejorar los procesos de su negocio.

There are many software quality models that allows a process of continuous improvement with its implementation. In this paper some characteristics of the investigated models are exposed, through an information revision, a classification of these models is performed according to the level of the process or product; each model count with some characteristics and a structure that is briefly stated in the written. The different enterprises in order to be immersed on a continuous improvement of their processes have identified the importance of getting the implementation of models that allows to certify an guarantee the quality of their processes and products, some success cases were found for the implementation of the studied models, which allowed the enterprises to position or stand by the improvement of their business process.

Existem diferentes modelos de qualidade de software que permitem processo de melhoria contínua com a sua implementação. Neste escrita características dos modelos investigados através de uma revisão das informações forem definidos, a mesma classificados de acordo com o nível de processo ou produto é feito; cada modelo tem características e uma estrutura que brevemente indicado na carta. Diferentes empresas, a fim de ser imerso em um processo contínuo de melhoria identificaram a importância de começar a implementação de modelos para certificar e garantir a qualidade de seus produtos e processos, alguns casos de sucesso foram encontrados implementação dos modelos estudados, o que permitiu que as empresas a posicionar ou ficar para melhorar seus processos de negócios.

Sistema experto para determinar la frecuencia cardiaca máxima en deportistas con factores de riesgo / Expert system for determining the heart rate maximum in athletes with risk factors / Sistema especialista para determinar a taxa coraçao maximo em atletas com fatores de risco

En este trabajo se presenta un sistema experto (SE) que permite establecer la frecuencia cardiaca máxima en términos de porcentaje de intensidad, la duración de una sesión de entrenamiento y la frecuencia en días por semana. La base del SE es el conocimiento de profesionales en el área de medicina y del deporte, que ayuda a los deportistas con padecimiento de enfermedades o factores de riesgo a tomar mejores decisiones al momento de realizar ejercicio físico. Este sistema se desarrolló en un ambiente web para facilitar la adquisición de los datos por parte de los profesionales, permitiendo así, la incorporación de varios criterios donde la aplicación del algoritmo del SE y de minería de datos proveen a los deportistas resultados con soporte médico. El SE ha sido incorporado a un software que se encarga de monitorizar la frecuencia cardiaca en tiempo real en una disciplina deportiva, donde se evidenció el buen funcionamiento del SE.

This paper presents an expert system (SE) that establishes the maximum heart rate in percentage terms of intensity, duration of a training session and frequency in days per week is presented. The base SE is the knowledge of professionals in the field of medicine and sport that helps athletes suffering from diseases or risk factors make better decisions at the time of exercise. This system was developed in a web environment to facilitate the acquisition of data by professionals, thus allowing the incorporation of several criteria where application of the algorithm SE and mining provide athletes results with medical support. The SE has been incorporated into software that is responsible for monitoring the heart rate in real time in a sport where the proper functioning of the SE was evident.

Este trabalho apresenta um sistema especialista (SE), que estabelece a frequência cardíaca máxima em termos percentuais de intensidade, a duração de uma sessão de treinamento ea freqüência em dias por semana é apresentado. A base de SE é o conhecimento de profissionais no campo da medicina e esporte, que ajuda atletas que sofrem de doenças ou factores de risco a tomar melhores decisões no momento do exercício. Este sistema foi desenvolvido em um ambiente web para facilitar a aquisição de dados por profissionais, permitindo a incorporação de vários critérios, quando a aplicação do algoritmo SE e mineração oferecer aos atletas resultados com apoio médico. A SE foi incorporado no software que é responsável por monitorar o ritmo cardíaco em tempo real em um esporte onde o bom funcionamento da SE foi evidente.