Ankle prosthesis design for transtibial amputation

People who suffer an amputation at the transtibial level choose to wear an ankle prosthesis to make their walk like a person without disabilities. In the present investigation, an ankle prosthesis design and simulation are made, which involves a restricted patella mechanism and a linear actuator capable of granting two degrees of freedom. A ball joint is designed where twelve springs that support the weight of a person are located, six springs comply with the eversion movement and the rest comply with the inversion movement, likewise, the actuator performs the dorsiflexion and plantar-flexion movements. The simulations were made in Inventor software. The results obtained on the ‘Y’ axis indicate a patella displacement in the inversion and eversion movement of 13.65 mm and 11.89 mm, respectively. These values are obtained when a tension of 1876.1 N is applied to the twelve springs. With these data obtained, stability and support for a person weighing 70 kg can be guaranteed, in addition, the established movement angles are com-plied. The prosthesis was built using additive and subtractive manufacturing.