Development And System Integration Of Simultaneously Monitoring Equipment For Respiration And Rumination Of Dairy Goats Based On Acoustic Signal

In recent years,the market scale of goat milk products has continuously expanded.According to statistics,the market size of goat milk powder in China was 11.1 billion yuan in2021 and is expected to exceed 20 billion yuan by 2026.With the booming development of the goat milk market,intelligence is an inevitable trend in the dairy goat industry.Individual physiological monitoring of dairy goats is an essential part of intelligent farming.Respiration and rumination are basic physiological indicators of dairy goats,and achieving synchronous monitoring of respiration and rumination behavior in dairy goats is of great significance for the health monitoring of diseased goats and other special individuals.Wearable monitoring technology may interfere with the natural state of dairy goats,and existing non-contact monitoring technology cannot achieve synchronous monitoring of respiration and rumination.Additionally,it is limited by the orientation of the tested goats and cannot monitor their respiration and rumination when they are facing away from the equipment or in obstructed scenes.Addressing the shortcomings of existing research,this thesis proposes a sound-based system for the synchronous monitoring of respiration and rumination in individual dairy goats.By leveraging the rich multipath reflection effects of sound waves in the pen and the periodic nature of respiration and rumination,the system achieves robust monitoring of the goats’ position and orientation during respiration and rumination.The specific contents of this thesis are as follows:(1)Ultrasound multiplex synchronous transceiver platform.To achieve interference-free synchronized monitoring of the respiration and rumination of the tested dairy goat,a multi-channel synchronized ultrasonic transceiver platform was designed to address the problems of low coverage and poor synchronization of existing audio equipment.The platform is mainly composed of twelve circular speakers and a USB sound card.The twelve circular speakers can emit omnidirectional ultrasonic waves,and when outputting 44 k Hz electrical signals,the attenuation is only about 0.6 d B relative to 1 k Hz output,with a good acoustic frequency response curve.The USB sound card has a high sampling rate of up to 96 k Hz,with synchronous transmission and reception sampling.It can maintain stable real-time performance for up to 10 hours of continuous operation.The platform can be used on system hosts such as Raspberry Pi and laptops.(2)Synchronized monitoring system for respiratory and ruminant behavior of dairy goats.Based on the multi-channel synchronized ultrasonic transceiver platform constructed,a synchronized monitoring system for respiratory and rumination behaviors of dairy goats was built.To address the lack of synchronized monitoring capability for respiratory and ruminant behavior in existing methods,this study proposes a synchronized monitoring method based on system acoustic impulse response.This method first utilizes the multipath effect of acoustics in indoor spaces to achieve omnidirectional acquisition of chest heaving during goat respiration and mouth chewing during ruminant behavior.Then,the impulse response of the received signal is calculated to capture the periodic variation characteristics of the multipath signal caused by respiratory and ruminant movements.The respiratory and ruminant signals are then separated using the frequency difference between them.Finally,after amplitude normalization and phase synchronization,the respiratory and ruminant waveforms are visualized.(3)Test of synchronized monitoring system for respiratory and rumination behaviors of dairy goats.This article presents experimental tests of the synchronized monitoring system for the respiratory and rumination activities of dairy goats.By comparing the respiratory and rumination frequencies detected by the system with the actual movements captured by a camera,the monitoring capability of the respiratory and rumination synchronization system was verified.The experiments were conducted on individual dairy goats of different breeds.The results showed that the maximum relative error of the respiratory frequency was 6.25%,the average relative error of the rumination frequency was 3.51%,the maximum relative error of the rumination frequency was 4.76%,and the average frame drop rate was 2.49%.These results indicate that it is feasible to use a system based on sound waves and impulse response to achieve synchronized monitoring of the respiratory and rumination activities of dairy goats.The system is robust to the position and orientation of the dairy goats,adaptable to the pause and resumption behaviors of rumination,and resistant to common noise,thus providing technical support for the subsequent acoustic monitoring of infectious diseases and health of individually fed dairy goats.