Research On Silicone Rubber Soft Sensor For Piantar Pressure Measurement

Plantar pressure measurement is an essential link in the field of exoskeleton assistance,human sports medicine,lower limb rehabilitation training and so on.At present,the existing plant-pressure measuring devices on the market are expensive,limited in use scenarios,poor wearing comfort,and can not be bent.In this paper,the inductive strain sensor is made by embedding the metal wire into the silicon rubber based on the excellent bending resistance of the silicon rubber.The range of the sensor can be adjusted by the modulus of the silicon rubber,and the sensor can be used to measure the plantar pressure,which is expected to greatly improve the reliability of the plantar pressure measuring device.Centered on this new strain sensor,the specific research contents of this paper are as follows:Firstly,based on the characteristics of the plantar pressure,the design of the detection scheme and the structure of the silicone rubber soft sensor suitable for the plantar pressure measurement was carried out.The advantages and disadvantages of capacitive silicon rubber soft sensor or inductive silicon rubber soft sensor are analyzed.After comprehensive comparison,inductive silicone rubber sensor was selected to study the preparation process of inductive silicone rubber sensor.The required silicone rubber modulus was calculated according to the fluctuation range of human foot pressure value,and then the silicone rubber model was determined.Multiple coils are connected in series to improve the initial value of inductance to meet the requirements of the system.The preparation process of multicoil package,the stable inlay process of metal wire and the lead process are studied.Secondly,to complete the design of the detection circuit of the silicon rubber soft sensor,which is a key and difficult point of this topic.The circuit is designed to detect the inductance change of the soft sensor and then map the pressure change acting on the soft sensor.According to the common methods of inductance detection at present,the characteristics of partial voltage method and bridge method are analyzed,and the detection principle of inductive silicon rubber soft sensor detection circuit is determined.And complete the design and production of the circuit board.Finally,the performance test and application of silicone rubber soft sensor are studied.Test the performance index of the sensor.The specific content includes: the sensitivity,linearity,repeatability and hysteresis of the silicon rubber soft sensor.On this basis,the silicon rubber soft sensor is applied to the measurement of plantar pressure,and the distribution of plantar pressure is given.