It is very difficult for stroke patients to complete the action of squatting-standing because their equilibrium function ability has been seriously declined. It was necessary, therefore, to do a deep research on the action of human squatting-standing and to set up an accurate model and simulation. In our modeling research, the movements of upper limbs and head was neglected, and a seven-segment model was developed to establish the coordinate system of human squatting-standing action. It calculated the knee joint moment and hip joint moment during squatting and standing by utilizing Lagrange method, and then simulated this mathematical model by utilizing Matlab. Geometric model of human squatting-standing was developed and simulated in ADAMS which proved that the established Lagrange model was reasonable. It would also provide significant theoretical references for further study and development of squatting-standing rehabilitation training equipment.
This article presents the design of a treadmill of comprehensive training experiment for rats. The treadmill is composed of six tracks and two of them were designed as conventional plane, two were designed to swing right and left, and two were designed to swing back and forth. The power was provided by six motors. The MSP430F149 is used as core to adjust the swing rate and the grade of electric shock. The IAR for MSP430 is used to design the software. The speed of the six tracks could be adjusted between 0 and 30 m/min. The swing tracks of back and forth can be swung for 3-25 times per minute and the swing tracks of right and left for 3-32 times. The electric shock can be divided into three levels, i.e. strong, middle, and weak level for each track. The digital comprehensive training treadmill can meet different training needs, and provide experimental data for mechanism research of some related diseases.
Exercise-induced muscle fatigue is a phenomenon that the maximum voluntary contraction force or power output of muscle is temporarily reduced due to muscular movement. If the fatigue is not treated properly, it will bring about a severe injury to the human body. With multi-channel collection of lower limb surface electromyography signals, this article analyzes the muscle fatigue by adoption of band spectrum entropy method which combined electromyographic signal spectral analysis and nonlinear dynamics. The experimental result indicated that with the increase of muscle fatigue, muscle signal spectrum began to move to low frequency, the energy concentrated, the system complexity came down, and the band spectrum entropy which reflected the complexity was also reduced. By monitoring the entropy, we can measure the degree of muscle fatigue, and provide an indicator to judge fatigue degree for the sports training and clinical rehabilitation training.