Development Of A Compression Force Detection System For Compression Stockings

The use of medical varicose vein compression stockings is an important means to prevent and treat varicose vein diseases.However,the dynamic detection of their compression force is a major problem and there is a lack of uniformity standards and rules in how to evaluate the test results.Although there are some relevant standards for medical compression stockings in China,the detection regulations for compression stockings are not accurate enough.And there is a short of mature methods and instruments for the detection of compression force.As a result,those products are not completely suitable for patients.Rapid and accurate detection of compression force is conducive to the evaluation and development of medical compression stockings.At the same time,it can promote the development of the private customized varicose vein compression hosiery industry.In order to detect the compression force of compression stockings,first of all,it is necessary to accurately measure the leg circumference parameters of different positions of the human legs.And then,stretch the compression stockings to a specified length according to the leg circumference parameters of each position and collect the corresponding sensor values.Finally,the values of the sensor are transformed to the required compression force values by the Laplace formula.Therefore,this article develops a compression stocking compression force detection system based on the IAP15W413AS single-chip microcomputer and VS2010 programming software.At the same time,the applicability of the Laplace transform formula is also verified in this work.First of all,this article designs a multi-chuck compression sock clamping device with the combination of dynamic and static chucks.The rotation of the drive motor is converted into the linear motion of this device through a set of linear bearings and a lead screw guide mechanism.This device has a smooth contact surface with the compression socks and will not damage the compression socks.At the same time,the clamping method is simple and easy to operate,which facilitates the installation and disassembly of the compression socks.Then,a method of fitting the actual bending shape of the human leg with a non-uniform cubic B-spline curve is proposed in view of the problem that the leg circumference parameters at different measurement positions of the human leg are not easy to determine.According to the curve equation,the leg circumference parameters at the corresponding position of the clamping device is calculated.The leg circumference parameters are calculated to obtain the specific position of the linear movement of the clamping device,and the communication software is used to control the drive motor to realize the stretching movement of the compression socks.The compression force detection system designed in this paper can continuously and dynamically measure compression socks without damaging the compression socks.It can measure the compression force of multiple positions at one time.It is also suitable for compression socks of different specifications.The operation is simple and the ultimate measurement result is the compression force,which is directly displayed in the software window.The compression force detection system designed in this paper belongs to the indirect test method of compression force.The final compression force is obtained from the tension value of the pressure sensor through the Laplace transformation formula.In the previous studies,the Laplace transformation formula are all quoted directly,and their principles,rationality and accuracy are not discussed.Therefore,design experiments and the balloon-type fluid pressure direct test method is adopted to verify the Laplace transform formula.The test results show that the theoretical value calculated by the Laplace formula and the actual measured value are in the range of allowable error,which indicates that the compression force detection system designed in this paper has a certain feasibility.In the follow-up research,the accuracy of the system can be further improved and can be used in the research of private customized medical compression stockings.