Footplate-free newton-euler based gait analysis and its application to the design of a knee-supporting lower limb exoskeleton

Wearable exoskeletons have been an area of research interest especially in the last 20 years. Wearable exoskeletons are basically divided into two categories according to their intended use: military and medical/rehabilitation. Within the scope of this thesis, ground reaction forces were estimated without using a Newton-Euler-based footplate. Additionally, the aim is to design, analyse, and produce a prototype of an exoskeleton that will provide joint range of motion (JROM) in the knee for rehabilitation purposes, both for individuals who can only walk painfully due to knee joint wear and for whom surgery is not possible, and for the period prior to total knee replacement surgery. There are brace-type wearable exoskeleton structures developed for this purpose in the literature. In this thesis, a wearable exoskeleton that will be used for the entire lower extremity with support from the ground has been developed. In addition, in this system, in accordance with human biomechanics, the knee joint will perform not only rotational movement with the hinge connection, but also both rotational and translational movement with the four-bar mechanism to be used. This system will be driven by electric motors to support the person. In this way, it is envisaged that the wearable exoskeleton system will provide both knee joint clearance and benefit the lower extremity muscle groups of the person. Within the scope of the thesis, the studies in literature are reviewed, and especially the studies on the lower extremities are focused. In the next section, the biomechanics of gait is discussed, and information on the subject is given. In the following chapters, motion simulations of all lower extremity limbs and centers of gravity are performed using MATLAB software and gait data. In the next section, the calculation of ground reaction forces and Achilles tendon forces using the equilibrium equations are discussed respectively. It has been observed that the results given by the MATLAB code and the experimental data taken as reference match. In this method, it is shown that ground reaction forces can be estimated using only anthropometric data, kinematic data, and IMU sensors, and without a force plate. Since the developed wearable exoskeleton is a structure that will move simultaneously with the person, it should be designed according to the anthropometric measurements of the person. Here, as a study, the values of the Achilles tendon forces for the conditions with and without wearing an exoskeleton were investigated, and this verification was carried out on a design. For this purpose, the design of the wearable exoskeleton is discussed in the next section of the thesis. In Chapter 3 of the thesis, which is about the production of the prototype, the production stages of the system are shown. In this section, hip, knee and ankle joints, which can move in harmony with joint movements, are examined under a different subheading, as it is critical to ensure joint range of motion. In order to explain each production stage of the wearable exoskeleton more easily, the lower extremity limbs are also explained under separate headings. In the 4th chapter of the thesis, the findings are discussed and conclusions and recommendations are made, and evaluations and suggestions are made about the topics that may be related and/or close to the thesis subject.