Fused deposition modeling (FDM) is a fast-expanding additive manufacturing technique for fabricating various polymer components in engineering and medical applications. The mechanical properties of components printed with the FDM method are influenced by several process parameters. In the current work, the influence of nozzle temperature, infill density, and printing speed on the tensile properties of specimens printed using polylactic acid (PLA) filament was investigated. With an objective to achieve better tensile properties including elastic modulus, tensile strength, and fracture strain; Taguchi L8 array has been used for framing experimental runs, and eight experiments were conducted. The results demonstrate that the nozzle temperature significantly influences the tensile properties of the FDM printed PLA products followed by infill density. The optimum processing parameters were determined for the FDM printed PLA material at a nozzle temperature of 220°C, infill density of 100%, and printing speed of 20 mm/s.

Fused deposition modeling (FDM) is an extensively used method for additive manufacturing of thermoplastic materials. It is growing in a variety of engineering applications because of its ability to produce complicated structural designs with low manufacturing time. However, the mechanical characteristics of the 3D printed components are extremely dependent on the proper selection of the printing conditions. In this present work, the impact of three foremost printing parameters, including fill density, extrusion temperature, and printing speed, is examined on the hardness of poly-lactic acid (PLA) parts. Taguchi design of experiment (DOE) methodology is used to minimize the total experimental runs and evaluate the optimal printing parameters for the maximum hardness of the printed part. Analysis of S/N ratios is utilized for establishing the optimal printing parameters, and the corresponding percentage contribution of control factors is measured using ANOVA. The study results have shown that extrusion temperature profoundly influences the hardness of the 3D printed PLA specimens, while printing speeds have a much smaller impact on it.

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Research in biomechanics has numerous applications including rehabilitation which helps in the fabrication of assistive devices. The Assistive devices or exoskeletons are used to serve the patients affected by stroke and spinal cord malfunctioning. These devices are programmed to follow a fixed redundant gait cycle and are lacking in producing natural movement of the gait. To overcome this limitation and make the device more user comfortable during usage of their daily life activities, a thorough study was done using an open source software that contributed to the design of exoskeleton device for the subject. In the current study, a simulation of various daily life activities are thoroughly studied using a musculoskeletal simulator package like OpenSim. The paper presents the observations of muscle responses from ground reaction forces with minimized metabolic cost function in various activities of daily living such as sitting to standing, standing to sitting, jumping, twisting suddenly while walking and turning suddenly. The study deliberates the inputs for developing more comfortable exoskeletons in performing tasks in a more sophisticated manner.

Ankle foot orthosis (AFO) device improves the walking ability by hold and directs the position and advancement of the lower limb, specifically ankle movement. The primary function of AFO is to correct the deformities of the damaged nerves and compensate for the weak & paralyzed muscles. Traditional AFOs are handcrafted using plaster moulds for generating patient's geometry, by a thermoforming process. Hence, the fabrication of a customized AFO consumes more time and expense as well. In the current review paper, it is discussed thoroughly about the upcoming technology known as additive manufacturing and its potential application for the production of customized AFOs. This review aimed to present the different AFOs produced by the additive manufacturing processes along with gait performances and material properties compared to the traditionally manufactured AFOs.