Design Of Wearable Interactive Gait Monitoring System

Gait is a reflection of a person’s physical condition and athletic performance.Gait monitoring is the monitoring of gait parameters such as hip angle,knee angle,ankle angle,gait cycle and step count to analyze whether the walking status is abnormal,and is widely used in medical,safety,sports and fitness fields.Currently,wearable devices are ideal for gait monitoring because they are comfortable to wear and easy to integrate.However,wearable devices have a single means of interaction with the user in gait monitoring,and the accuracy of monitoring gait parameters is vulnerable to the interference of the wearer and the wearing position.To address these problems,this paper investigates interactive wearable gait monitoring.Firstly,a multi-joint information acquisition system is designed,which consists of a wearable resistive interactive sensor and a wearable capacitive tensile sensor for extracting hip,knee and ankle joint bending angle information under walking;secondly,a calibration and solution model of multi-joint gait parameters is established to solve gait parameters from multi-joint information,and finally,a wearable interactive gait monitoring system is built to realize gait parameters Finally,a wearable interactive gait monitoring system is built to realize real-time monitoring and interactive training of gait parameters.The main contents of this paper are as follows.(1)Establishing a multi-joint information acquisition system based on wearable stretch sensors.Firstly,the wearable resistive interactive sensor is designed based on fabric technology,which has the ability to monitor joint bending and luminous interactivity.Secondly,the wearable capacitive stretch sensor and the wearable resistive interaction sensor were selected based on the performance index to form a multi-joint information acquisition framework;among them,the wearable resistive interaction sensor was placed at the knee joint and the wearable capacitive stretch sensor was placed at the hip and ankle joints.Finally,the electronic technology is applied to design the sensor signal conditioning circuit to acquire the bending angle information of the three joints in walking respectively.(2)A calibration and solution model of multi-joint gait parameters was established to extract gait parameters.First,in order to reduce the influence of the wearer and wearing position of the wearable stretch sensor on the joint angle measurement,optical acquisition means are introduced to calibrate the relationship between the output electrical signal of the wearable stretch sensor and the joint angle.In addition,to solve the problem of data desynchronization between the optical sensor and the wearable stretch sensor during acquisition,this paper proposes a multidimensional data optimal synchronization algorithm based on feature point detection,which can automatically obtain the optimal time synchronization between multi-dimensional data.Secondly,based on the least squares method to fit the linear relationship between the output of the wearable stretch sensor and the joint angle,the calibration equations are obtained to solve the angles of hip,knee and ankle joints;based on the automatic wave detection algorithm and weight setting to fuse the multidimensional sensor signals,the gait period and step number are solved.The experimental results show that the errors of joint angle,gait period and step number solved by the calibration and solution model of multi-joint gait parameters are less than 7%,3% and 1%,respectively.(3)Based on the proposed multi-joint information acquisition system and the calibration and solution model of multi-joint gait parameters,a wearable interactive gait monitoring system is designed and implemented,which consists of a multi-joint acquisition system,a cloud server,and a monitoring application.The system can meet the user’s demand for real-time gait monitoring and gait abnormality warning,and also meet the demand for autonomous training of gait with multi-modal interaction.