Design And Integration Of Wearable Impact Testing Equipment Based On MEMS

Traumatic brain injury occurs frequently during the war and the production of life.In the war environment,shock wave damage and shrapnel injury caused by the explosive device are the main causes of head injury.In daily life,the impact of transport,fall and a variety of industrial accidents can lead to different degrees of brain injury.Mild to moderate traumatic brain injury can be easily overlooked and missed the best treatment time because its appearance is not obvious.In order to detect the external environment load which causes traumatic injury,the establishment of protective equipment equipped sensors is necessary.The purpose of this paper is to design and develop a wearable impact detection device,which uses the MEMS sensors and high-performance single-chip microcomputer recording the impact events.According to the standard of the head injury,the injury grade is graded so as to get the medical intervention as soon as possible,the data collected can also be used for post-processing and analysis.The main contents of this paper are as follows.(1)To analyze the domestic and international research progress on the cause of traumatic injury and head injury criteria and combine the practicality of the product and the cost of the system,this paper presents the overall program of wearable impact detection equipment,selecting the pressure and acceleration as the main cause of head injury.By carrying pressure sensors and three-axis acceleration sensors,the device detects the magnitude and direction of the overpressure and acceleration.The data is processed by the microcontroller to do the initial injury classification,and also stored in the MicroSD card for post-data processing.(2)The design of hardware and software architecture is implemented to realize the system function,as well as the low-power design of the system.The system can reduce the overall power consumption by selecting the low-power hardware devices and the different working state of the system and automatically detecting the impact events.In the process of data storage,the design method of the communication module with software FIFO buffer is proposed to reduce the loss of data and improve the efficiency of the software.(3)Through the Multisim circuit simulation,static characteristics and dynamic characteristics of system pressure module is tested.During the simulation experiment,the sensitivity calibration of the system pressure module is completed.The time-domain characteristic and the frequency-domain characteristic of the pressure sensor peripheral circuit are tested.In the frequency range of 1 ? 100 Hz,the system follows better,the time response is about 2ms,the phase deviation is 20 °,which can meet the practical application requirements.