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Many hand accidents are reported around the world resulting in a necessity to perform a procedure of amputation of the hand. For this consideration, a large number of hand prostheses have been designed. However, the mechanical design of these prostheses present challenges such as kinematic functionality, strength, and cost. The present article analyses the mechanical design of a low-cost practical hand prosthesis using the finite element method with the help of Abaqus commercial software. Functional and technical requirements were considered to consider the biomechanics of the human hand. The hand prosthesis was conferred with 14-degrees-of-freedom (DOF), which gives it the capacity for grips associated with security, stability, dexterity, and sensibility. Additionally, due to practicality and low-cost manufacturing techniques, fused deposition modelling with acrylonitrile butadiene styrene (ABS) is proposed. The evaluation of the hand prosthesis was carried out by tensile, flexural, and torsional load conditions. Finally, the mechanical effectiveness of the designed prosthesis was demonstrated since maximum stresses close to 13 MPa were computed, which are less than the yield stress of ABS.

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In this paper, the energy absorption response of single and multi-cell profiles with different cross sections under bending load is presented. Emphasis was given to the modeling of damage initiation criteria and damage evolution. For this purpose, several discrete models of thin-walled structures were developed using Abaqus/Explicit. To obtain reliable results, a numerical study of a double-chambered profile under quasi-static three-point bending was conducted and validated experimentally. The studied structures included profiles with triangular, square, hexagonal, and circular cross-sectional shapes. The beams were fabricated with aluminum alloy EN AW-7108 T6 and modeled with ductile, shear, and Müschenborn-Sonne forming limit diagram damage initiation criteria. From the numerical results, both single and multi-cell profiles show an improvement in crashworthiness performance as their cross sections tend to approach a circle. In this way, an improvement of up to 80.95% in the crush force efficiency (CFE) parameter was obtained. Similarly, the introduction of ribs allowed for an increase in the energy absorption performance of the profiles relative to the single structure (non-ribbed). In this sense, an increase in specific energy absorption (SEA) and CFE values of up to 40% and 69% was calculated. Relative to single profiles, a maximum resistance to bending and an increase in energy absorption are observed when the circular cross section is reinforced in the longitudinal and transverse directions. Finally, with the improvements found, the design of an impact door beam used in the automobile industry is presented and discussed.

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