×
The submission system is temporarily under maintenance. Please send your manuscripts to
Go to Editorial ManagerThe modern development in prosthetics field demand the evaluation of the dynamical behavior and automatic control .The key process in the design and implement of these devices is the determination of the model parameters inherited with the transfer function .In such complicated structures it is so difficult to evaluate transfer function analytically ,however experimental approaches can serve as a simple and effective tool for estimating transfer function and model parameters .In this regard computer software such as Matlab is used .System Identification SID refers to the method for estimating the system transfer function from experimental tests by using computer .In the present paper; SID method is employed for analyzing below-knee prosthesis leg .In order to simulate with the practical requirement for design and evaluation ,two phases of human gait are considered ,namely; swing phase and single support of stance phase .The validity of this method is firstly checked by applying it on clamped-clamped beam model where the required parameters are evaluated and compared theoretically (via modal analysis) and experimentally (via System identification) .It is found that ; the error in estimating the transfer function parameter of beam is not exceeded 6% . Then the transfer function of the prosthesis are estimated for two phases of gait cycle .It is found that; the estimated transfer function of the prosthesis leg is highly affected by the phase type of gait cycle , where ;the natural frequency highly increases, the static gain decrease for support phase as compared with the swing phase ,however the damping ratio does not affected .
This work involved two major parts: the first one is the experimental part which included treatment of scoliosis deformity by manufacturing thoracolumbosacral orthosis, measuring the cobb angle of deformity, measuring the gait cycle data and walk path for both legs and suggesting a composite material to improve the mechanical properties of the orthosis and finally the interface pressure between trunk and orthosis is measured for twelve points covering of the total TLSO surface area by using f-socket devise. The second part of this study is the numerical simulation part during which the stresses are calculated using Ansys software for calculating stresses due to interface pressure loading boundary condition. The result shows no deference in gait cycle phases but the clear difference noted in walking path due to deviate center of mass, maximum pressure recorded left thoracic region with 900KPa due to correct spinal deformity while the minimum pressure recorded at right chest with l40KPa because of it is tissue region and Maximum value of stress was recorded at the left thoracic region with 2.81MPa due to Maximum interface pressure at this point.
This study compares two different sockets, traditional and smart. It includes designs, manufacturing, and testing to evaluate the influence of the socket designs on gait symmetry. The proposed materials are locally available in the prosthetics center where traditional sockets are manufactured. and smart socket designs with the same materials as traditional additions. A simple electronic system programmed to control the movement of the stump by pneumatic pads and prevent slipping during movement is considered an advanced suspension system. A gait cycle test was carried out to evaluate the sockets. it was performed on a patient with AK amputation in two cases: the first when the patient was wearing the traditional and the second when wearing the smart. Where the difference in (gait cycle time, step velocity, heel contact, and mid-stance) between the left and right leg is equal to (0.54, 4.3, 0.19, and 0.34) respectively, when the patient uses the traditional, while these values reduce to (0.09, 0.7, 0.07, and 0.27) respectively when the patient used the smart, it improves comfort by modifying pressure distribution, relieving pressure points, and enhancing functionality through gait analysis. They adjust to the volume of the residual limb, ensuring an effective fit. Real-time monitoring and remote modifications decrease the need for in-person meetings and enhance user confidence. The smart socket, designed to fit user requirements, provides enhanced comfort, functionality, and independence. The studies will explore its long-term benefits and broader applications, focusing on its originality, practical implications, and outcome measurement.
Total hip replacement (THR) is an elective surgical procedure with the primary indication being pain relief. The aim of this study is to analyze gait dynamics for patients after they underwent a unilateral THR surgery and compare it with normal parameters. To investigate the gait dynamics a gait analysis was performed on five patients after they underwent a unilateral THR surgery; only two of them were examined before the surgery. The gait analysis was performed using a digital video camera with two force plates. Kinematics data were obtained from 2D trajectories of seven passive markers using SkillSpector software. MATLAB software has been used for inverse dynamics computation. General gait parameters, Harris Hip Score, joints’ angles, forces, moments and powers were obtained during gait cycle. It was found that the average of improvement in Harris Hip Score (for four patients who were examined 1.5, 2.5, 3 and 9 months after surgery) is 61.8 points, which is an indication of pain relief. In the other hand, the general gait parameters were found slightly lower than normal after THR surgery. The average hip reaction force was found to be 2.988 N/BW, which is within normal range. Also, the average of maximum hip extension and maximum hip flexion angles were found to be 25.69 and -13.524 degree respectively, which both are within normal ranges. Furthermore, hip, knee and ankle moments and powers results showed some abnormality. Therefore as a conclusion, patient satisfaction and functional improvement are not related to general gait parameter. And it is not unusual that gait mechanics improvement would not reach normal after months of recovery. Also, the results of gait dynamics which are from the engineer’s perspective are compatible with Harris Hip Score, which is from the physician’s perspective, in quantifying surgical results and subsequent recovery progress.
This article is about studying the placing direction effect of a piezoelectric sensor on the shoe insole in the GRF results. Where the sensors used in this research are in two directions, along and perpendicular to the foot midline. In the both cases the sensors were fixed on the shoe insole to sense the foot pressure. For the first set of sensors which are perpendicular to the foot midline the collected data has similar trend to the GRF collected from the force plate, as the small lateral strain in the shoe insole due to the patient weight and GRF is close to the GRF data collected from other measurement system. On the other hand, the collected data from the second set of sensors which are in a longitudinal direction with the foot midline will have different trend and values from the collected data from the force plate or any other GRF measurement system. This different in the results is due to the large longitudinal strain in the shoe insole due to the patient weight which produce dissimilar results from the force plate result data.
There are many patients who face a lot of things that hurt the knee joint. Knee replacement is the best solution to these problems. This research was based on reducing the vibrations of daily activities as measured by the frequency of foot and knee for the patient for three cases when the bare foot, sports shoes with ground air and sports shoes with ground air with silicon damping. Patient information for this work was of age, weight, height and leg length 48 years, 90 kg, 160 cm, 84 cm, respectively. The results was shown that the decline in acceleration results was in the case of sport shoes with ground air with silicon damping with 22.57%, while the decline in vibration results was in the case of sports shoes with ground air with -54.9%.