Design e Fabricação de Órtese Ankle-Foot (AFO)
Autores
Ribeiro, ugusto Rocha
Parnes, Daniel
Kramer, Florencia Averame
Barros, Rodrigo Carvalho Monteiro de
Orientador
Valente, Carlos Magno de Oliveira
Co-orientadores
Citações na Scopus
Tipo de documento
Data
2023
Resumo
Este projeto teve como objetivo o aprimoramento da fabricação da Órtese
Tornozelo-Pé (AFO) produzida pela Associação de Assistência à Criança Deficiente (AACD).
O projeto buscou produzir a órtese por manufatura aditiva (MA) utilizando a metodologia
Fused Filament Fabrication (FFF), dando alternativas ao trabalho manual, automatizando o
processo e otimizando massa, custo e propriedades mecânicas do produto. A massa final da
peça devia ser igual ou menor, o custo não deveria aumentar em mais de 30%, mas era
desejado que diminuísse, e a resistência mecânica devia ser igual ou superior à da órtese atual,
permitindo leve flexão da região dos metatarsos, com o intuito de manter a marcha normal e
um retorno de energia em cada passada. O tamanho de AFO escolhido está relacionado com o
tipo de paciente a ser atendido, buscando que a órtese fabricada resista a carga de um paciente
adulto, tratando de uma AFO de tamanho grande. Para a escolha do material, foram realizados
ensaios de tração e compressão, dos quais se obteve o Módulo de Young e o Limite de
Escoamento. Se escolheu o ABS entre os materiais ensaiados devido a sua alta resistência,
rigidez e custo baixo. Para ter um modelo de AFO cujo teste fosse de fácil acesso, a perna de
um dos integrantes do grupo foi escaneada e foram projetados modelos de AFO’s sobre ela. O
design dessas órteses foi reforçado nas regiões críticas indicadas por simulações de elementos
finitos (MEF), no software NX Siemens. A simulação foi validada realizando ensaios de
flexão na órtese com regiões e níveis de aplicação de força equivalentes à simulação. Com a
simulação validada, os modelos de AFO foram iterados para otimizar a sua resistência e
conforto. O modelo final de AFO foi validado na marcha simples, já que a deformação obtida
no ensaio de validação representou uma envergadura menor que os 5º de dorsiflexão natural
do tornozelo. Se obteve, então, uma AFO com 58,62% da massa atual, aumento do custo para
111,51% do valor atual e aumento nas propriedades mecânicas de 308,06% no Módulo de
Young atual e 142,96% no Limite de Escoamento atual.
This project objective has to enhance the manufacturing of the Ankle-Foot Orthosis (AFO) produced by the Association for Assistance to Disabled Children (AACD). The project sought to produce the orthosis through Additive Manufacturing (AM) using the Fused Filament Fabrication (FFF) methodology, providing alternatives to manual labor, automating the process, and optimizing the mass, cost, and mechanical properties of the product. The final mass of the piece was intended to be equal to or less than the current mass, the cost should not increase by more than 30%, but a decrease was desired, and the mechanical strength should be equal to or greater than that of the current orthosis, allowing for slight flexion of the metatarsal region to maintain normal gait and energy return with each step. The chosen AFO size was related to the type of patient to be treated, aiming for the manufactured orthosis to withstand the load of an adult patient, resulting in a large-sized AFO. For material selection, tensile and compression tests were performed to obtain the Young's Modulus and Yield Strength. ABS was chosen among the tested materials due to its high strength, rigidity, and low cost. To have a readily testable AFO model, the leg of one of the group members was scanned, and AFO models were designed on it. The design of these orthoses was reinforced in critical regions identified through Finite Element Analysis (FEA) simulations in Siemens NX software. The simulation was validated by conducting bending tests on the orthosis with force application levels and regions equivalent to the simulation. With the validated simulation, the AFO models were iterated to optimize their strength and comfort. The final AFO model was validated in simple gait, as the deformation obtained in the validation test represented a deflection smaller than the natural 5° dorsiflexion of the ankle. The result was an AFO with 58.62% of the current mass, a cost increase of 111.51% of the current value, and an increase in mechanical properties of 308.06% in the current Young's Modulus and 142.96% in the current Yield Strength
This project objective has to enhance the manufacturing of the Ankle-Foot Orthosis (AFO) produced by the Association for Assistance to Disabled Children (AACD). The project sought to produce the orthosis through Additive Manufacturing (AM) using the Fused Filament Fabrication (FFF) methodology, providing alternatives to manual labor, automating the process, and optimizing the mass, cost, and mechanical properties of the product. The final mass of the piece was intended to be equal to or less than the current mass, the cost should not increase by more than 30%, but a decrease was desired, and the mechanical strength should be equal to or greater than that of the current orthosis, allowing for slight flexion of the metatarsal region to maintain normal gait and energy return with each step. The chosen AFO size was related to the type of patient to be treated, aiming for the manufactured orthosis to withstand the load of an adult patient, resulting in a large-sized AFO. For material selection, tensile and compression tests were performed to obtain the Young's Modulus and Yield Strength. ABS was chosen among the tested materials due to its high strength, rigidity, and low cost. To have a readily testable AFO model, the leg of one of the group members was scanned, and AFO models were designed on it. The design of these orthoses was reinforced in critical regions identified through Finite Element Analysis (FEA) simulations in Siemens NX software. The simulation was validated by conducting bending tests on the orthosis with force application levels and regions equivalent to the simulation. With the validated simulation, the AFO models were iterated to optimize their strength and comfort. The final AFO model was validated in simple gait, as the deformation obtained in the validation test represented a deflection smaller than the natural 5° dorsiflexion of the ankle. The result was an AFO with 58.62% of the current mass, a cost increase of 111.51% of the current value, and an increase in mechanical properties of 308.06% in the current Young's Modulus and 142.96% in the current Yield Strength
Palavras-chave
Órtese Tornozelo-Pé (AFO); Fused Filament Fabrication (FFF); Comparação de materiais; Elementos finitos; Design; Ankle-Foot Orthosis (AFO); Fused Filament Fabrication (FFF); Material Comparison; Finite Element Analysis; Design
Titulo de periódico
URL da fonte
Título de Livro
URL na Scopus
Idioma
pt
Notas
Projeto realizado para a empresa AACD - Mentor na empresa: Eric Buonpater Lee Santos
Membros da banca
Valente, Carlos Magno de Oliveira
Marcos, Gustavo Pollettini
Miagava, Joice
Área do Conhecimento CNPQ
ENGENHARIAS