Research On Body Lower Limb Spasticity Rehabilitation Device

There are some senile diseases increasingly because of growing aging population rapidly, such as cerebral hemorrhage, hypertension and so on. And especially hemiplegia caused by cerebral hemorrhage becomes the problem of modern rehabilitation medicine. Currently clinical rehabilitation has obtained certain achievements but most of the rehabilitation centers still adopt the exoskeleton robots to help to recover limbs. The advantage of exoskeleton robot is that it makes people finish rehabilitation therapy by imitating normal walk. But the ROM of patients during spasticity is much too little and limb remains straight, so it’s easy to cause the second injury if movement angle is out of safe angle when patients do basic rehabilitation. Based on this situation, we will design a new device of lower limb spasticity rehabilitation so as to meet the needs of the patient in the period of spasticity.First of all, I do some research on the pathology of hemiplegia caused by lower limb spasticity, understand the structure and motion mechanism of lower limbs and then I summary the main ways of clinical rehabilitation. Aiming at the rehabilitation methods to analyze the advantages and disadvantages of exoskeleton recovery and then based on the nerve recoverable theory, I come up with a new rehabilitation program--Intermittent Traction Method, meanwhile adopt a new control strategy--Force Closed-loop Control instead of PVT. In the aspect of structure design, I find some data related with human body and according to ergonomics we can make the best adaptability between people and machine. I decide to design it to chair that lifts the seat, linear actuator as driver, including two key DOFs to drive the knee and ankle joints. Backrest is adjustable within the range of 0～83° to ensure the patient’s comfort. In consideration of the recovery pattern and force, we need to analyze its kinematics, dynamics and strain simulation. Sensor system uses the pressure sensor and absolute encoder to collect force signal and angle signal to feed back to control system and evaluation indexes display on the screen for evaluating the rehabilitation process and then redact control flow chart preparing for editing program. Besides, we should ensure the safety of patients. In addition to the machinery limitation by itself, we need to design power scram button. If angle is more than safe value, this device must shut off electricity immediately.The recovery device I design is used for passive rehabilitation during spasticity. Because this stage is the most difficult, most complex and most important period. However, exoskeletal rehabilitation in the current market is throughout the treatment process, not focus on spasm stage and so application prospect of this rehabilitation device is very broad.