| Maintaining body balance is the primary condition for people to carry out normal production and life.Accurate and objective assessment of the ability of human body to maintain stable posture is of great social significance for elderly people prone to falls and patients with neurological impairment.Therefore,this paper uses a self-designed high-precision force measuring platform to evaluate the balance ability of the human body under static standing and external interference.The following work has been completed:(1)Filter the data collected by the force measuring platform to ensure the accuracy of the data.The time domain parameters and frequency domain parameters of the collected data are calculated with Matlab program.(2)The swing signal of the pressure center of stroke patients when standing was collected,and the collected data were drawn into a three-dimensional probability density map through Matlab program.The correlation analysis between the parameters extracted from the three-dimensional probability density map and the traditional time domain parameters was conducted to verify its ability to represent human balance.Verify the differences between the parameters without vision.According to the shape of the pressure center trajectory and its distribution in the front,back,left and right directions,the swing types of these patients at rest are also divided into five categories,which will help clinicians better determine the location of the focus of stroke patients and provide better diagnosis and rehabilitation plans.(3)Through time-frequency domain analysis of the pressure center data of normal young people under static eye opening,dynamic eye opening,static eye closing and dynamic eye closing,the difference of human body balance under different states is compared.It also reveals the certainty and randomness of the time series of the pressure center through the recursive quantitative analysis method,which can explore the local structure of the posture swing through the repeated patterns in the time series.For different vision and different interference conditions,the features extracted from the recursive graph can distinguish the balance ability of the human body in different states.(4)The small-angle non-equilibrium model of human standing at rest is abstracted into a single-pendulum inverted model and a double-pendulum inverted model for dynamic simulation analysis.Meanwhile,the intermittent control mode of human standing is introduced.The effectiveness of the simplified model for controlling human balance is verified through simulation analysis of the model. |
