Integration of IMU Sensors with Fugl-Meyer Assessment for Evaluating Lower Limb Rehabilitation in Stroke Patients

In this study, we have researched and developed a compact wearable device to assist doctors in monitoring and evaluating the recovery of lower limb function for stroke patients. The research used IMU sensors to collect the joints' angles values when exercising under instruction of doctors. The data were evaluated based on the FUGL-MEYER assessment scale. By collecting the boundary values of the lower limb joint angles (hip, knee, ankle), and then scoring these boundary values based on the criteria in the FUGL-MEYER scale, doctors can evaluate the recovery of lower limb function in patients. In fact, during experiments IMU sensors were easily affected by environmental noise. Thus in order to ensure the accurate operation of the sensors, Kalman filter is applied to predicts changes in deviation and makes real-time adjustments to minimize the errors. After researching and developing the device, the system was installed on healthy individuals in the first trial. The results showed that the joint angle values obtained from the IMU were quite accurate compared to the actual joint angles of the lower limbs. Therefore, in the next phase, the device is expected to achieve similar accuracy when tested on stroke patients. In conclusion, our research has initially succeeded in developing a compact, easy-to-use device model with relatively high accuracy to assist doctors in evaluating the recovery of stroke patients' function.