CN103487397A - Quick detecting method for hardness of phyllostachys pracecox shoots and device - Google Patents

Abstract

The invention discloses a method and device for quickly detecting the hardness of bamboo shoots, comprising: 1) collecting the reflectance of bamboo shoots corresponding to characteristic wavelengths; 2) converting the obtained reflectances at each wavelength into absorbance values; 3) converting each The absorbance was brought into the multiple linear regression equation to calculate the hardness of Lei bamboo shoots. The invention also discloses a device for implementing the above-mentioned detection method, including a stage, a sample fixing profiling rubber seat, a hemispherical spectrum collection box, a light source system, a computer, a single-chip microcomputer module, and welding between the stage and the hemispherical spectrum collection box Elastic support feet are provided, the center of the bottom of the hemispherical spectrum collection box is integrally formed with a central opening, and the hemispherical spectrum collection box is also equipped with a handle. The invention mainly detects the hardness of the bamboo shoots quickly and accurately through the characteristic wavelength, greatly shortens the detection time, and provides a basis for the automatic cutting of the bamboo shoots.

Description

A method and device for rapid detection of hardness of bamboo shoots

technical field

The invention belongs to the field of quality detection of bamboo shoots, and in particular relates to a rapid detection method and device for the hardness of thunder bamboo shoots.

Background technique

Bamboo shoots contain amino acids necessary for the human body, as well as various trace elements and cellulose. It is a low-sugar, low-fat, high-protein, high-fiber green health food. Hardness is an important indicator for evaluating the quality of bamboo shoots. Cutting bamboo shoots with different hardness can make the best use of them and create better economic value. The traditional bamboo shoot hardness testing method usually uses a hardness tester for perforation testing. This method is a destructive testing method, and the testing speed is slow, which cannot meet the rapid testing needs of large sample groups in the bamboo shoot cutting process. Therefore, it is of great significance to study the method of non-destructive, rapid and accurate detection of the hardness of bamboo shoots for the storage and automatic cutting of bamboo shoots.

The wavelength range of near-infrared light is about 780 ~ 2500 nm. It is an electromagnetic wave between visible light and mid-infrared light. It forms organic molecules by interacting with hydrogen-containing groups of organic molecules in substances such as C-H, O-H, and N-H bonds. Doubling and combined frequency absorption spectra. According to information characteristics such as the location and absorption intensity of these near-infrared spectra, combined with chemometric methods, quantitative or qualitative analysis can be performed on the quality characteristics of the measured substance. Near-infrared spectroscopy has the advantages of simple operation, fast measurement speed, and no pollution, and has been widely used in petrochemical, food, agriculture, pharmaceutical and other fields.

Contents of the invention

The purpose of the present invention is to provide a method and device for rapid detection of the hardness of thunder bamboo shoots. It can quickly collect the reflectance of certain specific wavelengths of bamboo shoots, and quickly and accurately detect the hardness of bamboo shoots through multiple linear regression models, providing a basis for automatic cutting of bamboo shoots.

The rapid detection method of a kind of thunder bamboo shoot hardness is characterized in that comprising the following steps:

1) Collect the reflectance of thunder bamboo shoots corresponding to the characteristic wavelengths: 1181nm, 1719nm, 1867nm, 1494nm, 2296nm, 2122nm, 1144nm, 1441nm, 1028nm, 2416nm, 1164nm , 1909 nm, 1000 nm, 2448 nm and 2037 nm;

2) Convert the obtained reflectance at each characteristic wavelength into an absorbance value;

3) Bring each absorbance value into the multiple linear regression equation: y = -133.34 λ ₁ + 92.17 λ ₂ + 72.93 λ ₃ – 62.03 λ ₄ – 33.60 λ ₅ + 48.72 λ ₆ – 71.16 λ ₇ + 41.46 λ ₈ + 66.87 λ ₉ – 19.90 λ ₁₀ + 46.08 λ ₁₁ +0.76 λ ₁₂ – 47.09 λ ₁₃ + 23.17 λ ₁₄ - 25.21 λ ₁₅ + 1.39, the hardness of the bamboo shoot is calculated;

In the equation, y is the hardness of the measured bamboo shoots, and λ ₁ ~ λ ₁₅ are 1811 nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, Absorbance of test sites corresponding to wavelengths of 1909 nm, 1000 nm, 2448 nm and 2037 nm.

Since bamboo shoots are non-transparent media containing various organic components, when light waves are irradiated on its surface, most of the light is reflected except for part of the light being absorbed, and the amount of light wave absorption is related to the chemical composition or physical properties of bamboo shoots , while the bamboo shoot hardness attribute is related to the chemical composition or physical properties of the bamboo shoot, especially related to the reflectivity of a small number of light waves with certain characteristic wavelengths.

The fast detection method of described a kind of thunder bamboo shoot hardness is characterized in that the acquisition of described characteristic wavelength adopts the following steps:

1) Collection of raw materials of bamboo shoot samples: choose bamboo shoots with a length greater than 30cm and a root diameter greater than 5cm as the sample raw materials;

2) The sample raw material in step 1) was cut longitudinally, and a leaf puncher with an inner diameter of 1.5 cm was used to punch holes in the internodes of the bamboo shoots to obtain a sample with a diameter of 1.5 cm and a thickness of 1 cm;

3) Use Antraris II Fourier transform near-infrared spectrometer to collect the near-infrared diffuse reflectance spectrum of the sample in step ² ). 8 cm ^-1 , when scanning, the optical fiber probe is in direct contact with the circular surface of the bamboo shoot, and the collected near-infrared diffuse reflectance spectrum data is collected and converted with TQ Analyst 9.1 software;

4) Use a texture analyzer to measure the longitudinal hardness data of the thunder bamboo shoot sample. The measurement method is: use a P2N needle probe to measure the probe penetration depth of 5mm at three test points on the circular plane of the sample with an interval of 120°. The hardness is averaged as the final hardness of the sample.

5) Use the Monte Carlo sampling algorithm to eliminate abnormal samples and determine the spectral data of the sample set;

6) Firstly, the adaptive competitive weighting method is used for the primary selection of the characteristic wavelength in the wavelength range of 1000-2500nm, and irrelevant variables are eliminated, and some variables related to the hardness of Lei bamboo shoots are initially obtained, and then the continuous projection algorithm is further used for the secondary selection of the characteristic wavelength. second choice, get these. The characteristic wavelengths are 1811 nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448 nm and 2037 nm. Using the absorbance of the bamboo shoots at the above-mentioned wavelengths as an input variable and the hardness of the bamboo shoots measured as an output variable, multiple linear regression was performed to obtain the above regression equation.

The described device for rapidly detecting the hardness of thunder bamboo shoots comprises a stage, a sample fixing profiling rubber seat cooperating with the stage, a hemispherical spectrum collection box, a light source system, a computer, and a single-chip microcomputer module, and the hemispherical The inside of the shaped spectrum collection box is equipped with a ring-shaped spectrum receiver bracket, and the spectrum receivers are evenly distributed on the ring-shaped spectrum receiver bracket. The light source system is arranged on the top of the hemispherical spectrum collection box. The spectrum receiver and light source The system is connected with the single-chip microcomputer module, and the single-chip microcomputer module is connected with the computer through a USB data line, and it is characterized in that elastic supporting feet are welded between the stage and the hemispherical spectrum collection box, and the center of the bottom of the hemispherical spectrum collection box is integrally formed A central opening is provided, and a handle is provided on the hemispherical spectrum collection box.

The device for quickly detecting the hardness of bamboo shoots is characterized in that there are 16 spectral receivers.

The described device for quickly detecting the hardness of bamboo shoots is characterized in that there are 3 elastic supporting legs, and the 3 elastic supporting legs are evenly arranged at 120° to be welded with a hemispherical spectrum collection box.

The device for quickly detecting the hardness of bamboo shoots is characterized in that the spectral receiver includes a photosensitive sensor, an optical filter, and a first Fresnel lens installed in sequence.

The device for quickly detecting the hardness of bamboo shoots is characterized in that the light source system includes an LED light source and a second Fresnel lens arranged under the LED light source, and the wavelength range of the LED light source is 1000-2500nm.

The device for quickly detecting the hardness of bamboo shoots is characterized in that the inner wall of the hemispherical spectrum collection box is provided with a white layer.

The device for quickly detecting the hardness of bamboo shoots is characterized in that the single-chip microcomputer module can provide a cross-flow signal with adjustable size to supply power to the light source, and the single-chip microcomputer module is built-in. , Display and transfer data and results to computer for data storage and reproduction.

The device for rapidly detecting the hardness of bamboo shoots is characterized in that the multiple linear regression equation is y = -133.34 λ ₁ + 92.17 λ ₂ + 72.93 λ ₃ - 62.03 λ ₄ - 33.60 λ ₅ + 48.72 λ ₆ - 71.16 λ ₇ + 41.46 λ ₈ + 66.87 λ ₉ – 19.90 λ ₁₀ + 46.08 λ ₁₁ +0.76 λ ₁₂ – 47.09 λ ₁₃ + 23.17 λ ₁₄ - 25.21 λ ₁₅ + 1.39, y in the equation is the hardness of the measured part of the bamboo shoot: λ ₁ ~ λ ₁₅ are the wavelengths of 1811 nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448 nm and 2037 nm respectively The absorbance of the corresponding test site of bamboo shoots.

The beneficial effects of the present invention are:

1. The rapid and convenient detection of the hardness of thunder bamboo shoots is realized, and the measurement accuracy is high;

2. Using a small number of characteristic wavelengths for multiple linear regression analysis, it has strong anti-interference ability and low cost;

3. It has a wide range of applications. Filters with other central wavelengths can be selected according to the actual situation. By modifying the multiple linear regression model, it can be used to detect the hardness of bamboo shoots or other quality indicators in different regions and varieties.

4. The present invention is mainly used to quickly and accurately detect the hardness of thunder bamboo shoots through the spectrum of characteristic wavelengths, which greatly shortens the detection time and reduces the detection cost, and lays the foundation for the storage and automatic cutting and grading of fresh bamboo shoots.

Description of drawings

Fig. 1 is the structural representation of bamboo shoot hardness rapid detection device;

Fig. 2 is the distribution schematic diagram of spectral receiver in the device shown in Fig. 1;

3 is a scatter distribution diagram of the prediction results of the calibration set samples in the embodiment of the present invention;

Fig. 4 is a scatter distribution diagram of the predicted structure of the test set samples in the embodiment of the present invention;

In the figure, 1-stage, 2-elastic support feet, 3-sample fixed profiling rubber seat, 4-hemispherical spectrum collection box, 5-spectrum receiver, 6-computer, 7-single-chip microcomputer module, 8-light source System, 9-LED light source, 10-second Fresnel lens, 11-handle, 12-ring spectrum receiver bracket, 13-photosensitive sensor, 14-filter, 15-first Fresnel lens, 16- Center opening.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1: a device for quickly detecting the hardness of bamboo shoots, including the following components: stage 1, elastic support feet 2, sample fixing profiling rubber seat 3, hemispherical spectrum collection box 4, spectrum receiver 5, computer 6. Single-chip microcomputer module 7, light source system 8, LED light source 9, second Fresnel lens 10, handle 11, ring spectrum receiver bracket 12, photosensitive sensor 13, optical filter 14, first Fresnel lens 15. The spectrum receiver 5 and the light source system 8 are connected to the single-chip microcomputer module 7, and then connected to the computer 6 through a USB data line. The top of the hemispherical spectrum collection box 4 is embedded with a light source system 8, and an LED light source 9 is placed in the light source system 8. The center of the bottom of the hemispherical spectrum collection box 4 is integrally formed with a central opening 16. After the LED light source 9 emits light, it passes through the second Fresnel The lens 10 focuses the light onto the sample to be measured. A handle 11 is installed on the hemispherical spectrum collection box 4, which can be used for mobile measurement. The three elastic support feet 2 are evenly distributed at 120° and welded with the hemispherical spectrum collection box 4, and the measured part can be made to cling to the central opening 16 at the bottom of the hemispherical spectrum collection box 4 through the elastic support feet 2. The inner wall of the hemispherical spectrum collecting box 4 is white, so that the illumination is uniform.

As shown in Figures 1 and 2, a ring-shaped spectrum receiving bracket 12 is installed inside the hemispherical spectrum collection box 4, and 16 spectrum receivers 5 are evenly distributed on the circumference of the ring-shaped spectrum receiving bracket 12, and the centerlines of each spectrum receiver 5 intersect In the center of the central opening 16 of the light source system 8 . A photosensitive sensor 13 , an optical filter 14 and a first Fresnel lens 15 are installed on each spectrum receiver 5 . The central wavelengths of the 15 filters are 1811 nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448nm and 2037nm. One of the 16 sets of filters and photosensitive sensors is used as the reference wavelength, and the remaining 15 sets are involved in the calculation.

The photosensitive sensor 13 collects the light wave reflectance of the characteristic wavelength through the optical filter 14 of the characteristic wavelength. The so-called characteristic wavelengths refer to those wavelengths whose reflectivity is related to the hardness of bamboo shoots.

Example

Acquisition of characteristic wavelengths:

1) Select bamboo shoots with a length of 30 cm and a root diameter of more than 5 cm as the sample raw material, cut them longitudinally, and use a blade puncher with an inner diameter of 1.5 cm to punch holes in the internodes of the bamboo shoots to obtain samples with a diameter of 1.5 cm and a thickness of 113 samples of 1cm;

2) An Antraris II Fourier transform near-infrared spectrometer was used to collect the near-infrared diffuse reflectance spectra of the above samples. Acquisition conditions: room temperature: 20±2°C; scanning range: 10000-4000 cm ^-1 ; scanning times: 64 times; resolution: 8 cm ^-1 ; the optical fiber probe was in direct contact with the circular surface of the bamboo shoot during scanning, and the spectral data were collected by TQ Analyst 9.1 (Thermoelectric Nicolis, USA) software for acquisition and conversion;

3) Use a texture analyzer (Beijing Weixunchao Instrument Technology Co., Ltd.) to measure the longitudinal hardness data of the bamboo shoot sample. The measurement method is: use a P2N needle probe to probe three test points on the circular plane of the sample at intervals of 120° The penetration depth is measured at 5mm, and the hardness of the three points is averaged as the final hardness of the sample;

4) Use Monte-Carlo Sampling (MCS) to eliminate abnormal samples, and finally the entire sample set has 108 spectral data;

5) Firstly, the Competitive Adaptive Reweighted Sampling (CARS) is used for the primary selection of the characteristic wavelength, and then the continuous projection algorithm (Successive Projections Algorithm, SPA) is used for the secondary selection of the characteristic wavelength, which can not only avoid the direct If the time is too long caused by the continuous projection algorithm, it can further eliminate irrelevant variables and improve the accuracy of the model. The characteristic wavelengths of the present invention are respectively 1811 nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448 nm and 2037 nm nm. 15 photosensitive components receive light waves of 15 wavelengths respectively;

The present invention first measures 108 samples at 1811 nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448 nm and The reflectance at these wavelengths at 2037 nm is then converted into absorbance by log(1/ R ) ( R is the reflectance), and then 72 samples are selected as the calibration set by the concentration gradient method, and the remaining 36 samples are used as the test set, At the same time, the hardness of 108 bamboo shoot samples was detected by traditional method. Taking the absorbance value corresponding to each characteristic wavelength of the calibration set sample as the independent variable, and the corresponding measured value as the dependent variable, the following multiple linear regression equation is obtained by using the multiple linear regression method (Multiple Linear Regression, MLR): y = -133.34 λ ₁ + 92.17 λ ₂ + 72.93 λ ₃ – 62.03 λ ₄ – 33.60 λ ₅ + 48.72 λ ₆ – 71.16 λ ₇ + 41.46 λ ₈ + 66.87 λ ₉ – 19.90 λ ₁₀ + 46.08 λ ₁₁ + _0.76 λ 309 – ₄ 23.17 λ ₁₄ - 25.21 λ ₁₅ + 1.39, calculated to get the hardness of bamboo shoots.

In the equation, y is the predicted value of the hardness of the measured bamboo shoots; λ ₁ ~ λ ₁₅ are 1811 nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, Absorbance of bamboo shoot test sites corresponding to 1164 nm, 1909 nm, 1000 nm, 2448 nm and 2037 nm wavelengths.

Then use the above multiple linear regression equation to predict the hardness of the calibration set and test set samples respectively, and evaluate the prediction results. The closer the correlation coefficient and slope in the evaluation index are to 1, the smaller the root mean square error, the absolute value of the deviation and the intercept are, indicating the better the prediction performance of the model. The prediction results are shown in Table 1:

Table 1: Prediction and evaluation of hardness of bamboo shoot samples in calibration set and test set

As shown in Figure 3, the prediction results of the calibration set modeling analysis, that is, the comparison between the predicted value of the calibration set samples and the real value, and the model is used for the prediction of the test set samples to analyze the accuracy of the model. As shown in Figure 4 is the scatter distribution diagram of the prediction results of the test set samples. In the above table, the correlation coefficient between the predicted value of bamboo shoot hardness and the actual value measurement is greater than 0.9, the root mean square error of the calibration set and the root mean square error of the test set are small and the difference between the two is not large, so it is considered that the predictive performance of the model is relatively good. good. The above results illustrate that the application of the method of the present invention can quickly and accurately realize the detection of the hardness of bamboo shoots.

The method that above-mentioned device detects thunder bamboo shoot hardness is as follows:

Place the bamboo shoots on the sample fixed profiling rubber seat 3, align the measured part of the bamboo shoots with the center of the central opening 16 at the bottom of the hemispherical spectrum collection box 4, and then connect the LED light source 9 through the single-chip microcomputer module 7, and the light is irradiated to After the measured part, the photosensitive sensor 13 only accepts the light reflected by the first Fresnel lens 15 at a specific wavelength through the optical filter 14, and uses the light intensity received by the 16th photosensitive sensor as a reference to convert the other 15 features For the reflectivity of light waves at the wavelength, the single-chip microcomputer module 7 receives the data and converts it into an absorbance value, which is brought into the multiple regression model to calculate the hardness of the bamboo shoots.

The device has a wide range of applications and can be used to measure the hardness of different types of bamboo shoots. The premise is that it only needs to determine the characteristic wavelengths of different types according to the above method, and then determine the multiple regression equation, and then put the multiple regression equation into the single-chip microcomputer module.

Claims (10)

1. the method for quick of a thunder bamboo shoots hardness is characterized in that comprising the following steps:

1) the acquisition characteristics wavelength the reflectivity of corresponding thunder bamboo shoots, described characteristic wavelength is respectively: 1181nm, 1719 nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448 nm and 2037nm;

Reflectivity under each characteristic wavelength that 2) will obtain is converted into absorbance;

3) bring respectively each absorbance into multiple linear regression equations: y=-133.34 λ ₁+ 92.17 λ ₂+ 72.93 λ ₃– 62.03 λ ₄– 33.60 λ ₅+ 48.72 λ ₆– 71.16 λ ₇+ 41.46 λ ₈+ 66.87 λ ₉– 19.90 λ ₁₀+ 46.08 λ ₁₁+ 0.76 λ ₁₂– 47.09 λ ₁₃+ 23.17 λ ₁₄-25.21 λ ₁₅+ 1.39, calculate the hardness of bamboo shoots;

The hardness that in equation, y is tested bamboo shoots position, λ ₁~ λ ₁₅be respectively the absorbance at 1811 nm, 1719nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448 nm and the corresponding test of 2037nm wavelength position.

2. the method for quick of a kind of thunder bamboo shoots hardness according to claim 1, what it is characterized in that described characteristic wavelength obtains the employing following steps:

1) the raw-material collection of thunder bamboo shoots sample: choosing length, to be greater than the thunder bamboo shoots that 30cm, root diameter (RD) be greater than 5cm be the sample starting material;

2) the sample starting material in step 1) are vertically cut open, the blade card punch that is 1.5cm with internal diameter is in the sampling of punching of the internodes of thunder bamboo shoots, and the acquisition diameter is 1.5cm, the sample that thickness is 1cm;

3) near-infrared diffuse reflection spectrum of sample use Antraris II ft-nir spectrometer acquisition step 2), acquisition condition is: 20 ± 2 ℃ of room temperatures, sweep limit 10000～4000 cm ^-1, scanning times 64 times, resolution be 8 cm ^-1, when scanning fibre-optical probe with thunder bamboo shoot circular surface, directly contact, the near-infrared diffuse reflection spectrum data of collection is gathered and is changed with TQ Analyst 9.1 softwares;

4) by vertical hardness data of instrumental test thunder bamboo shoots sample, adopt the P2N needle probe to carry out probe driving depth 5mm to three test points in 120 °, sample circular flat interval and measure, get its mean value as the sample final hardness;

5) adopt Monte Carlo sampling algorithm rejecting abnormalities sample, determine the sample set spectroscopic data;

6) first adopt the competitive method of weighting of self-adaptation, the secondary that adopts subsequently the successive projection algorithm to carry out characteristic wavelength is selected.

3. the device of a fast detecting thunder bamboo shoots claimed in claim 1 hardness, comprise objective table (1), be equipped with fixedly profiling rubber base (3) of sample on objective table (1), semisphere spectra collection box (4), light-source system (8), computing machine (6), one-chip computer module (7), the inner cooperation of described semisphere spectra collection box (4) is equipped with annular spectrum receiver holder (12), the upper uniform spectral receiver (5) that is provided with of annular spectrum receiver holder (12), described light-source system (8) is equipped with the top at semisphere spectra collection box (4), described spectral receiver (5) and light-source system (8) are connected with one-chip computer module (7), one-chip computer module (7) is connected with computing machine (6) by the usb data line, it is characterized in that between described objective table (1) and semisphere spectra collection box (4), welding is provided with resiliency supported pin (2), the one-body molded center drilling (16) that is provided with of described semisphere spectra collection box (4) bottom centre, also be equipped with handle (11) on semisphere spectra collection box (4).

4. the device of a kind of fast detecting thunder bamboo shoots hardness according to claim 3, is characterized in that described spectral receiver (5) is provided with 16.

5. the device of a kind of fast detecting thunder bamboo shoots hardness according to claim 3, is characterized in that described resiliency supported pin (2) has 3, described 3 resiliency supported pin even 120 ° and semisphere spectra collection box (4) welding setting.

6. according to the device of the described a kind of fast detecting thunder bamboo shoots hardness of claim 3 or 4, it is characterized in that on described spectral receiver (5) being equipped with successively light sensor (13), optical filter (14), the first Fresnel Lenses (15).

7. the device of a kind of fast detecting thunder bamboo shoots hardness according to claim 3, it is characterized in that described light-source system (8) comprises LED light source (9) and is arranged on second Fresnel Lenses (10) of LED light source (9) below, described LED light source (9) wavelength coverage is 1000-2500nm.

8. the device of a kind of fast detecting thunder bamboo shoots hardness according to claim 3, is characterized in that described semisphere spectra collection box (4) inwall is provided with the white print layer.

9. the device of a kind of fast detecting thunder bamboo shoots hardness according to claim 3, it is characterized in that described one-chip computer module (7) can provide size adjustable crossing current signal, for light source power supply, the built-in multiple linear regression equations of carrying out the hardness measurement of thunder bamboo shoots of one-chip computer module (7), for calculating, showing and data and result are transferred to computing machine, carry out storage and the reproduction of data.

10. the device of a kind of fast detecting thunder bamboo shoots hardness according to claim 9, is characterized in that described multiple linear regression equations is y=-133.34 λ ₁+ 92.17 λ ₂+ 72.93 λ ₃– 62.03 λ ₄– 33.60 λ ₅+ 48.72 λ ₆– 71.16 λ ₇+ 41.46 λ ₈+ 66.87 λ ₉– 19.90 λ ₁₀+ 46.08 λ ₁₁+ 0.76 λ ₁₂– 47.09 λ ₁₃+ 23.17 λ ₁₄-25.21 λ ₁₅+ 1.39, the hardness that in equation, y is the tested position of thunder bamboo shoots: λ ₁~ λ ₁₅be respectively the absorbance at the corresponding thunder bamboo shoots test of 1811 nm, 1719nm, 1867 nm, 1494 nm, 2296 nm, 2122 nm, 1144 nm, 1441 nm, 1028 nm, 2416 nm, 1164 nm, 1909 nm, 1000 nm, 2448 nm and 2037nm wavelength position.

Images