Virtual reality tool for balance training

Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Eletrónica Médica)Em todo o mundo, 15 milhões de pessoas sofrem um acidente vascular cerebral (AVC) por ano. Destas, 66% sobrevivem e metade delas ficam com incapacidade permanente de equilíbrio, limitando a sua independência motora e qualidade de vida. Estes pacientes podem recuperar o seu equilíbrio e independência motora através do fenómeno da neuroplasticidade, alcançado com intervenções de reabilitação. Asferramentas de realidade virtual (RV) podem ser utilizadas como complemento àsterapias físicas convencionais, promovendo treinos de alta repetição com estratégias de aprendizagem otimizadas. Assim, os ambientes virtuais podem ser personalizados de acordo com as necessidades iminentes dos pacientes, maximizando a reorganização do cérebro e plasticidade, aumentando a eficácia e acelerando a recuperação do equilíbrio. Não obstante, existe uma falta de ferramentas de RV neste campo, as quais não apresentam uma visão centrada no utilizador. Esta dissertação tem como objetivo conceber, desenvolver e validar uma ferramenta totalmente imersiva baseada em RV, seguindo uma visão centrada no utilizador. A ferramenta de RV desenvolvida inclui quatro desafios virtuais baseados em atividades do dia-a-dia (ADDs), compreendendo um total de nove tarefas motoras. A ferramenta de RV fornece estímulos visuais, sonoros e hápticos, através de óculos de RV, auscultadores incorporados, e comandos vibratórios. Paralelamente, foi realizado um estudo sobre as ADDs mais realizadas e apreciadas, com recurso a um questionário, provando que os desafios virtuais concebidos estão de acordo com a preferência da maioria das pessoas. A partir de uma validação preliminar com sujeitos saudáveis, verificou-se que a ferramenta de RV melhorou significativamente o deslocamento do centro de massa (CDM) na direção mediolateral (ML) e a velocidade mínima do CDM na direção anteroposterior (AP), durante a marcha. Além disso, o deslocamento do CDM e a velocidade máxima e mínima do CDM, nas direções AP e ML, embora não significativas, exibiram melhorias noutras tarefas motoras. Os testes clínicos também revelaram uma melhoria após o treino RV. A avaliação da experiência do utilizador provou a elevada aceitabilidade, valor e utilidade da ferramenta de RV. O trabalho futuro envolve a melhoria da ferramenta com mais e personalizados desafios virtuais e a validação do sistema com doentes durante treinos mais longos.Worldwide, 15 million people suffer a stroke each year. Of these, 66 % survive and half of them are left with permanent balance disabilities, limiting their motor independence and compromising their quality of life. The patients can recover their balance function and regain their motor independence through neuroplasticity phenomenon, achieved by rehabilitation intervention. Virtual reality (VR) tools may be used as a complement to physical therapies to promote high-repetitive training with optimised learning strategies. Thus, virtual environments can be customised according to the patient’s imminent needs, maximising brain reorganisation, allowing to increase the effectiveness and accelerate balance recovery. Nonetheless, there is a lack of VR tools in this field, and no user-centered design is available. This dissertation aims to design, develop, and validate a fully immersive VR-based tool, following a user-centered design. The developed VR tool includes four virtual challenges based on activities of daily living (ADLs), comprising a total of nine motor tasks. The VR-based tool provides visual, sonorous, and haptic stimuli, through a Head-Mounted Display (HMD), built-in headphones, and vibrotactile controllers. In parallel, a study about the most performed and appreciated ADLs was carried out, using a questionnaire, proving that the developed virtual challenges are in accordance with most peoples’ preferences. From a preliminary validation with healthy subjects, the VR tool significantly improved the user’s center of mass (COM) displacement in the mediolateral (ML) direction, and the minimum COM velocity in the anteroposterior (AP) direction when walking. Moreover, COM displacement and the maximum and minimum COM velocity on both AP and ML directions, although not significantly, also showed improvements in many other tasks. Furthermore, clinical tests revealed improvements after VR training. The user experience evaluation proved the high acceptability, value, and usefulness of the VR-based tool. Future work towards enhancing the VR-based tool with more and customised virtual challenges and extending the VR tool validation with end-users throughout a longer training period

Wearable virtual reality tool for balance training: the design and validation on healthy

Book series: Lecture Notes in Networks and Systems, ISSN 2367-3370, vol. 530Balance disabilities affect the human quality of life. Current directions for balance rehabilitation require the inclusion of virtual reality (VR) tools as a complementary robotic tool to conventional physical therapies to accelerate balance recovery. This works aims to present the design and validation on healthy of a wearable and fully immersive VR-based tool following a user-centred design. This wearable VR tool comprises four Activities of Daily Living-based virtual challenges including nine motor tasks, chosen according to those most performed in the literature, as well as in the tasks of the Berg Balance Scale (BBS) and Timed Up and Go (TUG) clinical tests. This system comprises wearable VR technology, providing multimodal feedback (visual, sonorous, and vibrotactile cues), and integrates wearable inertial sensors for real-time motor assessment. The system’s operability was validated with six healthy subjects executing BBS and TUG related motor tasks to assess balance performance after and before two training trials for each virtual challenge. The results showed statistically significant improvements regarding COM’ displacement and velocity during “Cooking” and “Watch Tv” games and after VR training. The VR-based tool was rated with high IPQ and IMI scores. This wearable VR-based tool has the potential to effectively improve balance and walking, and to effectively increase the user’s active participation and enthusiasm during balance training; thus, contributing to accelerate the user’s balance and motor recovery.This work has been supported by the FEDER Funds through the Programa Operacional Regional do Norte and national funds from Fundação para a Ciência e Tecnologia with the SmartOs project under Grant NORTE-01-0145-FEDER-030386, under the national support to R&D units grant, through the reference project UIDB/04436/2020 and UIDP/04436/2020, under scholarship reference 2020.05709.BD, and under Stimulus of Scientific Employment with the grant 2020.03393.CEECIND