Biomechanical design of a passive lower extremity gait support

Gait supports, known as exoskeletons, are wearable devices that work in interaction with human limbs and have been developed since 1890 to assist the user. Exoskeletons have begun to be used in industrial and civil life, especially in the military and health fields, with the increase of human machine interaction. In this thesis, biomechanical design and mathematical modeling of lower extremity gait support for people working standing for a long time has been performed. Thus, it is predicted that people working without serious health problems in the lower extremities due to prolonged standing will be able to work more comfortably and spend less metabolic energy. The designed model is based on the body measurements of a person with a height of 1.80 m and a mass of 80 kg. By creating static equilibrium equations, unknown forces and ankle moment have been found. After the equations in the model without exoskeleton was created, the equations were created to find the change of forces and ankle moment in the system with the designed walking frame model. The equations found using the position of the foot in the lower phases of the stance phase, as the foot contact with the ground during the swing phase of the gait cycle is very low. With the mathematical solution, the Achilles tendon strength, forces acting on the ankle and ankle moment were found for the lower extremity with and without gait support. The total deformation, the spring forces in the system and the elongation in the spring were obtained by analyzing in the computer program. With the help of the designed and calculated model, a system that works mechanically and helps to reduce metabolic energy by reducing the loads on the feet during walking has been proposed. In the system that will work mechanically, a simpler system is designed by adding springs parallel to the tendon in order to reduce the load on the Achilles tendon and to reduce the metabolic energy consumed during walking. Thus, an exoskeletons was created without the need for any external power requirement.