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CN-121994317-A - Non-contact milk flowmeter and flow measuring method based on near infrared receiver

CN121994317ACN 121994317 ACN121994317 ACN 121994317ACN-121994317-A

Abstract

The non-contact milk flowmeter based on the near infrared receiver comprises a milk pipeline, an infrared emission module, an infrared receiving array, a signal processing unit, a data processing module and a temperature monitoring module, wherein the temperature monitoring module is provided with a temperature sensor for detecting the temperature of the infrared receiver, each infrared emitter is used for generating an infrared beam with a preset wavelength to penetrate milk flowing in the pipeline, each infrared receiver is used for correspondingly receiving the infrared beam, the signal processing unit is used for processing received optical signals, the data processing module can calculate the instantaneous flow and the accumulated flow of the milk in real time based on the effective cross-sectional area of an inner side channel of the pipeline, and the temperature compensation parameters in milk flow calculation are adjusted based on the temperature of the infrared receiver. Therefore, the device has the advantages of simple structure, difficult damage, no pollution to milk due to non-contact metering, simple cleaning of only one milk pipeline, and more accurate calculation result by adopting a model algorithm.

Inventors

  • ZHANG XIAOWEN
  • WANG ZHIRAN
  • ZHANG DONG
  • ZHOU ZENGCHAN
  • ZHOU XUEQING
  • HAN GUITAO

Assignees

  • 北京市农业机械研究所有限公司

Dates

Publication Date
20260508
Application Date
20260205

Claims (10)

  1. 1. The non-contact milk flowmeter based on the near infrared receiver is characterized by comprising a pipeline (1) for milk to be measured to flow through, an infrared emission module (2), an infrared receiving array (3), a signal processing unit, a data processing module and a temperature monitoring module, wherein the infrared emission module (2) and the infrared receiving array (3) are oppositely arranged at two lateral sides of the pipeline (1) and correspondingly comprise at least two infrared emitters and infrared receivers which are arranged along the longitudinal direction of the pipeline (1) respectively, each infrared emitter is used for generating an infrared beam with a preset wavelength to penetrate milk flowing in the pipeline (1), each infrared receiver is used for correspondingly receiving the infrared beam, the signal processing unit is used for processing a received optical signal, the temperature monitoring module is provided with a temperature sensor for detecting the temperature of the infrared receiver, the data processing module can calculate the instantaneous flow and the accumulated flow of the milk in real time based on the effective cross-sectional area Z of the inner side channel of the pipeline (1), and adjust the temperature compensation parameters in the milk flow calculation based on the temperature of the infrared receiver as the temperature compensation parameters, the extreme value of the temperature compensation is set to take a complete shielding value H and a trigger value Y as the temperature reading value of the two ends, and the extreme value of the temperature compensation is compensated threshold value of the temperature compensation to the temperature of the two ends of the temperature threshold value of the infrared receiver is used for the temperature compensation threshold value of the temperature range of the temperature compensation of the temperature sensor, which is used for the temperature compensation of the end section: Y=Y 0 *[1+k*(T-T0)], H=H 0 *[1+k*(T-T0)], wherein Y is the signal value reading received by the infrared receiver when the flow rate is minimum, H is the signal value reading received by the infrared receiver when the flow rate is maximum, T0 is a preset calibration temperature value, k is a preset temperature coefficient, T is a real-time temperature monitoring value of the temperature sensor, Y 0 is the optical signal threshold received by the infrared receiver when the flow rate is minimum at the preset calibration temperature T0, H 0 is the optical signal threshold received by the infrared receiver when the flow rate is maximum at the preset calibration temperature T0, Determining a shielding proportion C based on an actual value U received by an infrared receiver, a trigger value Y and a complete shielding value H at corresponding temperatures: When U is equal to or less than H, c=1; when H < U < Y, c= (Y-U)/(Y-H); When U is more than or equal to Y, C=0, Multiplying the shielding proportion C by the inner diameter cross-sectional area S of the pipeline (1) to obtain an effective cross-sectional area Z: Z=C*S。
  2. 2. The near infrared receiver based non-contact milk flow meter according to claim 1, wherein the pipe (1) is configured as a translucent food-grade rectangular pipe and/or the pipe (1), the infrared emitting module (2), the infrared receiving array (3) are arranged inside the light-shielding type outer casing (4).
  3. 3. The near infrared receiver based noncontact milk flow meter as claimed in claim 1 or 2, characterized in that the conduit (1) is made of food grade PPSU material and/or the conduit has a cross section of 12mm long, 8mm wide and a cross section of 96mm2.
  4. 4. The near infrared receiver based non-contact milk flowmeter of claim 1, wherein the infrared emission module (2) and the infrared receiving array (3) are respectively provided with five infrared emitters and infrared receivers correspondingly, wherein the infrared emission module (2) adopts five infrared LED arrays for forming parallel light beams, wherein the four infrared emitters and the infrared receivers are respectively arranged adjacently in a field shape, thereby being provided with two groups of two infrared receivers arranged along the longitudinal direction of the pipeline (1).
  5. 5. The near infrared receiver-based noncontact milk flowmeter of claim 1, wherein the infrared receiving array (3) comprises photodiodes independently corresponding to signal amplifying circuits of the signal processing unit, the signal processing unit further comprises a transimpedance amplifying circuit, and the data processing module calculates the flow rate by using a lambert-bragg law model after the signal processing.
  6. 6. The near infrared receiver-based noncontact milk flowmeter of claim 1, wherein the data processing module comprises a dynamic baseline correction unit, a wavelet noise reduction processing unit and a flow calculation engine based on a light intensity flow relation model, wherein the dynamic baseline correction unit tracks a reference light intensity signal without milk flow in real time by using a dynamic baseline correction method, automatically compensates baseline drift, the wavelet noise reduction processing unit is used for carrying out wavelet decomposition on the baseline corrected signal to filter high-frequency noise, the flow calculation engine integrates the light intensity flow relation model constructed based on the lambert-Bragg law, calculates instantaneous flow by combining a temperature compensation threshold interval and a pipeline structure parameter, and obtains accumulated flow by integral operation.
  7. 7. The near infrared receiver based non-contact milk flow meter of claim 1, further comprising a flow display module for displaying instantaneous flow and cumulative flow simultaneously or based on a flow rate threshold or a cup off threshold switch.
  8. 8. The near infrared receiver based non-contact milk flow meter of claim 1, further comprising a heating circuit provided with a heating resistor (51) for heating the infrared receiver.
  9. 9. A milk flow measuring method, characterized in that the method is realized by adopting the non-contact milk flowmeter based on the near infrared receiver as claimed in any one of claims 1 to 8, and comprises the following steps: flowing milk through the duct (1); the infrared light beam emitted from the infrared emission module (2) vertically penetrates through the flowing milk, The infrared receiving array (3) detects the light intensity attenuation signal of the infrared light beam, The temperature monitoring module detects the temperature of the infrared receiver, The data processing module calculates and outputs an instantaneous flow and an accumulated flow value, Wherein the milk velocity V is calculated as V=L/Δt, Wherein L is the distance between two adjacent infrared receivers in the longitudinal direction of the pipeline (1), deltat is the sampling interval time used for milk to flow between the two infrared receivers, Calculating the instantaneous flow rate Q i :Q i = L/Δt x ρ x Z, Wherein ρ is the density of milk, i is the set number of sampling time intervals, Calculate the cumulative flow W:W= * , Where n is the total number of samples.
  10. 10. The milk flow measuring method according to claim 9, wherein the preset calibration temperature value T0 is 37 ℃, the preset temperature coefficient k is 0.39%/°c, Y 0 =3900,H 0 = 800, the infrared emitting module (2) adopts five infrared LED arrays with 940nm wavelength, and the emission power is 10-100 mw for forming parallel light beams with the diameter of 20-50 mm.

Description

Non-contact milk flowmeter and flow measuring method based on near infrared receiver Technical Field The invention belongs to the technical field of livestock equipment, relates to a non-contact milk flow detection device, and particularly relates to a non-contact milk flow meter and a flow measurement method based on a near infrared sensing technology, which are particularly suitable for real-time monitoring of milking processes of modern dairy farms. Background For domestic animal husbandry, traditional volumetric measurement type milk flowmeter equipment is comparatively behind, because mechanical flowmeter has the problem of milk direct contact part, easily receives milk corruption, and life 3~5 years, contact measurement mode easily causes secondary pollution moreover, influences milk quality. The existing electronic flowmeter has the defects of complex structure, high maintenance cost, lack of self-adaptive modification capability for measuring errors caused by temperature and illumination changes, no temperature compensation function and no function of switching and displaying instantaneous flow and accumulated flow. Disclosure of Invention The invention aims to provide a non-contact milk flowmeter, which can solve the technical problems of low measurement precision, large potential health safety hazard, difficult maintenance and the like in the prior art and can accurately measure instantaneous flow and accumulated flow simultaneously. The invention provides a non-contact milk flowmeter based on a near infrared receiver, which comprises a pipeline, an infrared emission module, an infrared receiving array, a signal processing unit, a data processing module and a temperature monitoring module, wherein the pipeline is used for allowing milk to be measured to flow through, the infrared emission module and the infrared receiving array are oppositely arranged at two lateral sides of the pipeline and respectively comprise at least two infrared emitters and infrared receivers which are arranged along the longitudinal direction of the pipeline and correspond to each other, each infrared emitter is used for generating an infrared beam with a preset wavelength to penetrate the milk flowing in the pipeline, each infrared receiver is used for correspondingly receiving the infrared beam, the signal processing unit is used for processing received optical signals, the temperature monitoring module is provided with a temperature sensor used for detecting the temperature of the infrared receiver, the data processing module can calculate the instantaneous flow and the accumulated flow of the milk in real time based on the effective cross-sectional area Z of the inner side channel of the pipeline, and can adjust the temperature compensation parameters in the milk flow calculation based on the temperature of the infrared receiver as temperature compensation parameters, and set temperature compensation threshold intervals with a complete triggering value H as extreme values at two ends are set to compensate the influence of ambient temperature on the reading of the infrared receiver. Y=Y0*[1+k*(T-T0)], H=H0*[1+k*(T-T0)], Wherein Y is the signal value reading received by the infrared receiver when the flow rate is minimum, H is the signal value reading received by the infrared receiver when the flow rate is maximum, T0 is a preset calibration temperature value, k is a preset temperature coefficient, T is a real-time temperature monitoring value of the temperature sensor, Y 0 is the optical signal threshold received by the infrared receiver when the flow rate is minimum at the preset calibration temperature T0, H 0 is the optical signal threshold received by the infrared receiver when the flow rate is maximum at the preset calibration temperature T0, Determining a shielding proportion C based on an actual value U received by an infrared receiver, a trigger value Y and a complete shielding value H at corresponding temperatures: When U is equal to or less than H, c=1; when H < U < Y, c= (Y-U)/(Y-H); When U is more than or equal to Y, C=0, Multiplying the shielding proportion C by the inner diameter cross-sectional area S of the pipeline to obtain an effective cross-sectional area Z: Z=C*S。 Preferably, the duct is configured as a translucent food-grade rectangular duct, and/or the duct, infrared emitting module, infrared receiving array are disposed inside the light-shielding type outer housing. Preferably, the tubing is of food grade PPSU material and/or the tubing has a cross-section length of 12mm, a width of 8mm and a cross-sectional area of 96mm2. Preferably, the infrared emission module and the infrared receiving array are respectively provided with five infrared emitters and infrared receivers correspondingly, wherein the infrared emission module adopts five infrared LED arrays for forming parallel light beams, and the four infrared emitters and the four infrared receivers are respectively arranged adjacently in a Chin