Modeling and Analysis of a Novel Smart Knee Joint Prosthesis for Transfemoral Amputation

Abstract

The absence of a limb impacts devastatingly on any person, especially if it is the lower limb as it is paramount to human locomotion. The effect of mobility loss reduces independence, and affects amputees’ lifestyles. A smart prosthetic knee joint is designed and manufactured in which the amputee above the knee can perform various daily and effective movements. It is distinguished by its distinctive and very high efficiency mechanically and electronically. The new design of the artificial smart knee joint has proven to be 100% successful as a passive mechanical movement. Should a power failure occur at the source, the ability to move smoothly is very high, proved highly efficient by walking, sitting, and applying various daily movement activities. The artificial knee joint is able to detect the movement of the residual limb according to the results of the movement study, thus allowing the prosthesis to simulate the biomechanics of the missing limb without any difficulty by using the finite element method (FEM) as a numerical technique. The results showed that 94.303 MPa and 0.1379 mm are the highest stresses and displacements experienced by the knee joints, respectively at 110°. This remains below the yield stresses of 339.15 MPa (depending on the properties of aluminum alloy material 2024-T3). On the other hand, the highest safety of factors was at 0° with a value of 5.5905 and the lowest safety of factors was at 110° with a value of 3.5964. The above results show that von Mises stresses and displacement increase with increasing the angle of flexion of the knee joint while the safety of factors decreases as the angle of flexion of the knee joint increases. The result of finite element analysis shows that the concept is safe enough to use for this specific topic.

A novel design of smart knee joint prosthesis for above-knee amputees

“…The following explains the relationship between the forces produced by the actuator and the torque of the knee joint [6]:…”

“…However, amputees consume around 60% more energy than others since walking requires the wearer's muscles [5]. A passive prosthesis balances the impedance with a power supply to assist with walking [6][7][8][9]. The user of the active prosthesis has less physical stress than with the passive prosthesis while still being able to walk normally.…”

Design and Control of Transfemoral Prosthesis Prototype with Magneto-Rheological Damper

“…In 2021, Kamel et al [15] modelled and analyzed a prosthesis for use in amputations of transfemoral nature presenting a smart knee joint of novel proportions. The finite element method was applied where it's found that the displacement values and stress test are directly proportional to the flexion angle of the designed knee joint.…”