Non Contact Heart Rate Measurement System Based On Zynq

With the development of economic and the intensification of aging,cardiovascular disease mortality accounts for more than 45% of residents’ disease mortality.Heart rate is an important parameter of cardiovascular disease,and its daily monitoring is increasingly important.However,traditional heart rate measurements are inconvenient for special groups such as infants and burn patients because of the need for contact.Therefore,non-contact heart rate measurement methods have attracted widespread attention.However,the existing researchs on non-contact heart rate measurement are computationally intensive,almost all calculations are carried out with PC or server,and there are few related researches carried out with mobile embedded devices.In addition,although have been developed for many years,there are few optical researches on non-contact heart rate measurement.This paper is based on Zynq(heterogeneous embedded platform)to achieve real-time non-contact heart rate measurement at low cost.The specific work contents are as follows:1.In view of the problem that there was no optical model to describe photoplethysmography method,a six-layer optical modeling was carried out on the skin.Monte Carlo method was used for the established model,and a Python language program was written to simulate the dynamic optical characteristics of the skin under diastolic and contraction states.2.According to the characteristics of the Zynq platform,a heart rate measurement algorithm suitable for Zynq was customized using the Python language.Image processing modules and part of calculation modules in the algorithm were made into hardware modules using Vivado HLS tools,and run on the programmable logic(PL)FPGA side of Zynq to achieve hardware acceleration.The ARM processor system(PS)side was used to run the remaining simple algorithms by C language,and it also undertook the control process of the entire system.The PS and PL co-processing scheme enabled the non-contact real-time heart rate measurement system to be successfully realized on the embedded platform.3.OV5640 camera was selected for measurement,and the hardware system was built in conjunction with Zynq platform.Then data measured by finger clip pulse oximeter as a control were used to form a set of hardware test platform.4.Experiments were designed and standard evaluation indicators in heart rate measurement were introduced to evaluate the system.The results show that the performance of this system was not much different from mainstream solutions under the premise of low cost.The evaluation indicators also showed the problems of the system from multiple dimensions,and provided ideas for subsequent improvements.