RU2642481C1 - Device for determining complex of geometric parameters of cross section of objects of quasi-cylindrical forms - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: device contains a laser triangulation sensor distances, mounted near the surface of the object so that the laser beam was in a plane and crossed the path section checkpoints, microprocessor measuring-computing block device for the rotation of the object around an axis of rotation passing through the central point within the cross-section perpendicular to the plane of the section, starting from the initial angular position every similar angular intervals so that within a single turnover number, distance sensor signal converter and a personal computer. The distance sensor is set at a specified adjustable distance from the axis of rotation of the object being monitored. Measurements of distances to control points are carried out through every identical angular interval. This provides the ability to determine the set of distances from the central point to the control points, located along the entire contour of the section, represent coordinates of control points in a rectangular coordinate system and calculate the geometric parameters of the cross section of the body by a measuring and computing unit.

EFFECT: simplification of the device by making measurements of distances to control points on the contour of the cross section using a single laser triangulation distance sensor.

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Description

The invention relates to the field of instrumentation, in particular, to means for determining the geometric parameters of the cross section of bodies of a quasi-cylindrical shape, mainly shtamb (for reference, shtam is the aerial part of the plant between the root and the first branch) of seedlings and rooted cuttings of garden crops to assess their quality .

When performing selection, research and agricultural work in the industrial cultivation of garden crops, instrumental quality control of the finished product (cuttings, seedlings) is necessary. One of the indicators of plant development and quality is the geometric parameters of the cross section of the stem: transverse dimensions, contour length, area, shape index (ratio of the maximum and minimum orthogonal transverse dimensions).

For measuring the transverse dimensions of the cross-section of the stem, mechanical contact devices with a mechanical or electronic scale are known, such as calipers and micrometers [GOST R 53135-2008. Planting material of fruit, berry, subtropical, nut, citrus crops and tea. Technical conditions - S. 38]. The measurement procedure by contact means is characterized by high complexity and low productivity associated with the manual installation of measuring jaws and planes before contact with the object of control. In order to obtain data for determining the cross-sectional area, it is necessary to measure the many transverse dimensions of the cross-section in different directions. In addition, contact with the surface of controlled garden crops is carried out with a certain measuring force, which leads to deformation of the soft tissues of the controlled objects and, as a result, to measurement errors due to changes in the size of the object.

A device for determining the parameters of the cross section of the body that does not cause deformation of the controlled plants and is based on measuring the volume of the plot of the stem by measuring the buoyancy force by electronic weights arising in accordance with the law of Archimedes, and then calculating the diameter and cross-sectional area of the cylinder, equivalent in volume and height to the controlled the site of the stem [RF patent No. 2547439, IPC A01G 7/00, A01G 1/00. Device for determining the geometric parameters of plants / V.V. Mineev, V.A. Zolotarev, A.F. Aleinikov, V.B. Morozov, A.S. Tikhonov, O.V. Elkin, V.M. Furzikov. - Application No. 2013122381/13, declared 05/14/2013, publ. 04/10/2015, bull. No. 10]. The device comprises a horizontal platform with electronic scales mounted on it and a vertical tripod equipped with a device for hanging plants, a vessel with liquid mounted on the scales, a linear displacement sensor of the device for hanging plants, which is made in the form of an arrow, rigidly fixed in a carriage moving along a guide along a tripod using a mechanical drive, and is equipped with a clip for fixing plants, as well as a microprocessor meter for geometric parameters of plants.

The advantage of the device is the expansion of functionality due to the additional determination, in addition to the volume of roots, also indicators of development of the aerial parts of plants - the cross-sectional area and diameter of the stem.

The disadvantage of this device is the error in measuring the volume of the site of the stem due to the absorption of fluid by the porous tissues of the stem.

Therefore, to control the geometric parameters of garden crops, non-contact means are more preferable, among which there is an optical device for measuring the cross-sectional diameter of the body, based on the shadow method [RF patent No. 2555497, IPC G01B 11/08. Device for measuring diameter / V.V. Mineev, V.A. Zolotarev, A.F. Aleinikov, V.B. Morozov, V.M. Furzikov. - Application No. 2014105249/28, declared 02/11/2014, publ. 07/10/2015, bull. No. 19]. The device contains an optical sensor, consisting of two blocks - the emitter and receiver. Radiation from a semiconductor laser or LED is collimated by the lens. When placing the object of control in the collimated beam region, its shadow image is scanned by a line of CCD photodetectors or formed by a telecentric optical system on a line of CCD photodetectors. Based on the position of the shadow boundaries, the processor calculates the diameter of the object.

The disadvantages of the device are the impossibility of its use to control the transverse dimensions of sections having concave sections, and the fact that only one parameter of the section of the body is determined is the diameter.

The closest analogue of the invention (prototype) in technical essence is a device using laser triangulation distance sensors to determine the complex of geometric parameters of the cross section of quasi-cylindrical bodies, mainly seedlings and rooted cuttings of garden crops [RF patent No. 2551264, IPC G01B 11/08. The method of determining the geometric parameters of the body section and device for its implementation / V.V. Mineev, V.A. Zolotarev, A.F. Aleinikov, V.B. Morozov. - Application No. 2013144512/28, declared 10/03/2013, publ. 05/20/2015, bull. No. 14].

The device (prototype) contains two laser triangulation distance sensors equipped with inputs for external start of measurements and mounted on a bracket-shaped housing at a predetermined distance from each other so that their measurement vectors lie on the same line and are directed in the opposite direction, as well as an element controlling the perpendicularity of the movement of the device relative to the line of measurement vectors of distance sensors, the sensor of the traveling clock, triggering the measurement of distance sensors, a microprocessor meter The computational unit is made with the possibility of moving relative to the controlled body so that the line of measurement vectors is in the plane of the controlled section and intersects the section contour at two control points.

The advantages of the prototype are: high accuracy, speed and resolution; thin visible beam and small dimensions of its measuring spot at the test object; work in difficult operating conditions; the ability to work with objects of various colors with a complex surface structure.

The disadvantage of the prototype is the need to use two laser triangulation sensors for measuring distances to control points, which complicates the device and increases its cost.

The technical result of the invention is the simplification of the device for determining the complex of geometric parameters of the cross section of quasi-cylindrical bodies by performing measurements of distances to control points on the cross section using a single laser triangulation sensor.

The technical result in the invention is achieved by the fact that in the device for determining the complex of geometric parameters of the cross section of the bodies of quasi-cylindrical shape, containing a laser triangulation distance sensor, equipped with an input for external start of measurements and installed near the surface of the body so that its laser beam is in the plane of the controlled section and crossed the section contour at control points, and a microprocessor measuring and computing unit, consisting of a microcontroller, module p memory, encoder, control buttons, alphanumeric liquid crystal indicator and adapter for connecting to a personal computer, while the first input of the microcontroller is connected to the memory module, and the second input is connected to the output of the encoder, the inputs of which are connected to the control buttons, the first output is connected to alphanumeric digital liquid crystal display, and the second output is connected to an adapter for connecting to a personal computer, a device has been introduced to rotate the controlled body around the axis of rotation, passing to it through a central point within the controlled cross section perpendicular to the plane of this section, starting from the initial angular position every equal angular intervals so that within one revolution their number is integer, the signal transducer of the laser triangulation distance sensor into a code, the output of which connected to the third input of the microcontroller, the input of the conversion start to the third output of the microcontroller, and the measuring input to the output of the laser triangulation dates distance meter, an input for external start of measurements of which is connected to the fourth output of the microcontroller, and a personal computer, the input of which is connected to the output of the adapter. The device for turning the controlled body consists of a stepper motor mounted on a horizontal platform so that on its shaft directed vertically upwards, a U-shaped holder of the controlled body is fixed at one end, the second end of which is equipped with a clip-type clip with semicircular lips for girth and holding the controlled body in an upright position, as well as the stepper motor control driver, while the axis of rotation of the stepper motor passes between the jaws and coincides with the axis of rotation of the control iruemogo body input driver connected to a fifth output of the microcontroller, and the driver output is connected to a control input of the stepper motor. The laser triangulation distance sensor is mounted on a horizontal platform at a predetermined adjustable distance from the axis of rotation of the controlled body so that its laser beam hits the contour of the controlled cross section of the body above the jaws of the clamp.

Such a combination of the above-mentioned features of the proposed technical solution of the device allows, as in the prototype, to obtain the coordinates of the set of control points on the cross-sectional contour, but using only one laser triangulation distance sensor, and, accordingly, using the known geometric relations to determine the necessary complex of geometric parameters of the transverse sections. That is, due to the fact that the proposed device rotates a quasi-cylindrical body and its cross section around a rotation axis located at a predetermined distance from the distance sensor and passing through a central point located within the cross section perpendicular to the plane of this section, it is possible to determine the lengths the set of rays emanating from this center point to the intersection points (control points) with the contour line of the cross section, using one laser a triangulation distance sensor that measures distances to control points in directions that coincide with the directions of the rays emanating from the center point. And also, due to the same specified angle between the rays and their integer within one revolution, it is possible to represent the coordinates of the control points in a rectangular coordinate system, taking the direction of the first ray coming from the center point coinciding with the abscissa axis, and further calculating the geometric parameters of the section body measuring and computing unit.

In FIG. 1 is a drawing explaining the design of a device for determining a complex of geometric parameters of a cross section of a quasi-cylindrical body using the example of a seedling, FIG. 2 is a structural diagram of a device for determining a complex of geometric parameters of the cross section of bodies of a quasi-cylindrical shape.

A device for determining the complex of geometric parameters of the cross section of a quasi-cylindrical body, for example, a stem 1 of a seedling 2 of a garden crop, contains a horizontal platform 3 on which a step motor 4, a laser triangulation sensor 5 distances (hereinafter referred to as 5 distance sensor) and an electronic unit 6 are installed consisting of a microprocessor measuring and computing unit 7, a signal transducer 8 (for example, voltage) of a distance sensor 5 to a code (for example, pulse number) (hereinafter referred to as expander 8 voltage per code) and driver 9 control the stepper motor 4 (hereinafter referred to as driver 9). On the shaft 10 of the stepper motor 4, directed vertically upward, the end 11 of the U-shaped holder 12 of the stem 1 of the seedling 2 of the garden culture is fixed. At the second end 13 of the U-shaped holder 12, a “clothespin” clip 14 is fixed with shanks 15 and semicircular lips 16 for grasping and holding the stem 1 of seedling 2 of the garden crop in an upright position. For a more stable and reliable retention of the stem 1 of the seedling 2, the clamp 14 is made double, the jaws 16 of which are provided with internally glued thin strips of soft material (not shown). The distance between the ends 11 and 13 of the U-shaped holder 12 is chosen so that the roots of the seedling 2 are freely placed between them. To reduce the bending forces on the shaft 10 of the stepper motor 4, the U-shaped holder 12 is equipped with counterweights (not shown). The axis 17 of rotation of the shaft 10 of the stepper motor 4 passes between the jaws 16 and, when the seedling 2 is installed in the clamp 14, coincides with the axis of rotation 18 of the stem 1 of the seedling 2. The distance sensor 5 is mounted at such a height relative to the horizontal platform 3 that its laser beam 19 to the contour 20 of the controlled cross-section of the stem 1 above the clamp 14 perpendicular to the axis of rotation 18 of the stem 1 and formed on it measuring spots 21, which are control points, and its imaginary continuation crossed this axis 18 at a point that is central th point of a controlled cross-sectional area. Microprocessor-based measuring and computing unit 7 in order to determine the lengths of the set of rays emanating from the central point to the measuring spots 21 (control points), and then the coordinates of the control points and geometric parameters of the cross-section of the stem (contour length, area, maximum and minimum sizes in two orthogonal directions and their relationship - shape index) consists of a microcontroller 22, a memory module 23, an encoder 24, control buttons 25, an alphanumeric liquid crystal indicator 26 (hereinafter - alphanumeric -Digital LCD 26) and connect the adapter 27 to the personal computer 28 (hereinafter - the adapter 27 and the PC 28). The first input of the microcontroller 22 is connected to the memory module 23, and the second input is connected to the output of the encoder 24, the inputs of which are connected to the control buttons 25, the first output is connected to the alphanumeric LCD 26, and the second output is connected to the adapter 27. The output of the voltage converter 8 the code is connected to the third input of the microcontroller 22, the conversion start input to the third output of the microcontroller 22, and the measuring input to the output of the 5 distance sensor, the input for the external start of measurements of which is connected to the fourth output of the microcontroller 22. PC input 28 connected to an output adapter 27. Entrance driver 9 is connected to the fifth output of the microcontroller 22, and the output driver 9 is connected to a control input of the stepper motor 4.

A device for determining the complex of geometric parameters of the cross section of the stem 1 of a seedling 2 of a garden culture works as follows. Before starting measurements using adjustments (not shown), the distance between the distance sensor 5 and the center point (or, which is the same, the distance between the distance sensor 5 and the axis of rotation 18 of the stem 1 of seedling 2) is set based on the dimensions of the body being monitored, and with the button control 25 "ON" by means of the encoder 24, driver 9 and under the control of the program of the microcontroller 22, the device is turned on and restored to its original state, while the stepper motor 4 is set to the initial angular position, and appears on the PC screen 28 tsya request for the input object attribute and mode measurements in the memory unit 23: the date, the serial number and name of the seedling 2, the values of the distance between the sensor 5 and the distance of the central point, the pitch angular interval of 1.8 or 3.6 degree. After entering the attributes of the object and the measurement mode with the control button 25 “START”, the device is transferred to the “Work” mode. In this mode, from the fourth output of the microcontroller 22, the command for measuring the distance to the surface of the stem 1 of seedling 2 (to the first measuring spot 21) is received at the input for external start of measurements of the distance sensor 5 and, with a certain time delay, the command for converting the voltage of the sensor 5 distances to the pulse number code from the third output of the microcontroller 22 to the start input of the voltage converter 8 to the code. Next, the number-pulse code from the output of the converter 8, carrying information about the measured distance, is fed to the third input of the microcontroller 22, where, under the control of the program of the latter, it is converted into a binary-decimal code, based on which the distance from the central point to the first control point is calculated, as the difference between the distance from the sensor 5 distances to the center point and the measured distance from the sensor 5 distances to the first control point. The obtained numerical value of the distance from the center point to the first control point is displayed on the screen of the alphanumeric LCD 26 and transmitted through adapter 27 to PC 28 to calculate the coordinates of the first control point. After the first measurement, from the fifth output of the microcontroller 22 to the input of the driver 9 control the stepper motor 4 receives a command to rotate the shaft one step in accordance with the selected value of the angular interval of 1.8 or 3.6 degrees. Then, from the fourth output of the microcontroller 22, the input for the external start of measuring the distance sensor 5 receives a command to perform the next measurement of the distance to the surface of the stem 1 of seedling 2 (to the next measuring spot 21), and the above cycle is repeated until the number of cycles equal to 200 or 100, respectively, the selected angular intervals of 1.8 or 3.6 degrees, and on the screen of the alphanumeric LCD 26 there will be no message about the end of the measurements and calculations of the initial parameters, while the special Other light or sound indicator (not shown). After pressing the “STOP” control button 25, the device is switched to the “Processing” mode, and based on the received initial parameters, the program of PC 28 calculates the coordinates of the control points and geometric parameters of the cross section of the stem 1 of seedling 2: contour length, area, shape index (maximum and minimum orthogonal transverse dimensions).

The coordinates of the control points are calculated as follows.

The central point is taken as the beginning of a rectangular coordinate system, the numerical value of the distance from the central point to the first control point is postponed from the coordinate system on the abscissa axis and the coordinates of the end of the segment are taken as the coordinates of the first control point, the coordinates of the remaining control points are obtained similarly by deferring the numerical values of the distances from the center point to the corresponding control points on the rays emanating from the origin at the corresponding angles no abscissa multiples of the angular interval selected step 1.8 or 3.6 degrees. The length of the contour 20 of the cross section is determined by the formulas of analytical geometry as the sum of the lengths of straight lines between all adjacent control points. The cross-sectional area is defined as the sum of all the elementary areas of the circle sectors, the central angle of which is equal to the selected step of the angular interval of 1.8 or 3.6 degrees, and the radii R of each of which are equal to the arithmetic average of two distances from the central point to each of two adjacent control points. The area of the circle sector S is calculated by the known geometric ratio of the area S and the radius R of the circle sector:

S = πR ² / N,

Where

S is the area of the unit sector of the circle;

π is a number equal to 3.14;

R is the radius of the unit sector of the circle;

N is the number of sectors in a circle of 200 or 100 with a selected step of the angular interval of 1.8 or 3.6 degrees, respectively.

To calculate the shape index, the maximum size is the length of the largest segment from the set of segments between all possible pairs of control points, the minimum is the sum of the maximum distance from this largest segment to control points lying on one side of it and the maximum distance from this largest segment to control points lying on the other side of it.

The obtained geometric parameters of the cross section of the stem 1 of the seedling 2 with its attributes are displayed on the screen of a personal computer 28 and stored in a file of its memory (for example, a hard disk).

The following components can be used to carry out the invention:

LS5 sensor NPP PRIZMA [URL: http: //www.prizmasensors.ru] - as a laser triangulation sensor 5 distances;

stepper motor 4 PL42H34-D5 [URL: http: //www.purelogic.ru];

driver 9 control the stepping motor PLD230 [URL: http: //www.purelogic.ru];

PIC16F876 chip [URL: http: //www.rudatasheet.ru] - for microcontroller 22;

microcircuit AD654 [URL: http: //www.datasheet4u.com] - for the converter 8 of the voltage signal of the sensor 5 distances in the number of pulse code;

microcircuit 74НS148 [URL: http: //www.alldatasheet.com] - for the encoder 24;

FM24C64 chip [URL: http: //www.alldatasheet.com] - for memory module 23;

microcircuit MAX232N [URL: http: //www.alldatasheet.com] - for adapter 27 connecting to PC 28;

indicator FECC1602D-FLYYBW-65SR [URL: http: //www.di-em.ru] - for the alphanumeric LCD 26.

Claims (3)

1. A device for determining the complex of geometric parameters of the cross section of quasi-cylindrical bodies, containing a laser triangulation distance sensor, equipped with an input for external start of measurements and mounted near the surface of the body so that its laser beam is in the plane of the controlled section and crosses the section contour at the control points, and microprocessor measuring and computing unit, consisting of a microcontroller, memory module, encoder, control buttons, alphanumeric LCD indicator and adapter for connecting to a personal computer, while the first input of the microcontroller is connected to the memory module, and the second input is connected to the output of the encoder, the inputs of which are connected to the control buttons, the first output is connected to an alphanumeric liquid crystal indicator, and the second output is connected to the adapter connection to a personal computer, characterized in that a device is introduced into it for turning a controlled body about an axis of rotation passing through a central point, n located within the controlled cross section, perpendicular to the plane of this section, starting from the initial angular position at every identical angular intervals so that within one revolution their number is integer, the signal transducer of the laser triangulation distance sensor to a code, the output of which is connected to the third input of the microcontroller , the conversion start input is to the third output of the microcontroller, and the measuring input is to the output of the laser triangulation distance sensor, the input is for it start a measurement which is connected to the fourth output of the microcontroller, and a personal computer having an input connected to an output adapter. 2. The device according to p. 1, characterized in that the device for turning the controlled body consists of a stepper motor mounted on a horizontal platform so that on its shaft directed vertically upwards, a U-shaped holder of the controlled body is fixed at one end, the second end of which equipped with a clip type “clothespin” with semicircular lips for grasping and holding the controlled body in an upright position, as well as a control driver for the stepper motor, while the axis of rotation of the stepper motor passes between bkami and coincides with the axis of rotation of the controlled body, the driver input is connected to the fifth output of the microcontroller, and the driver output is connected to a control input of the stepper motor. 3. The device according to claim 1, characterized in that the laser triangulation distance sensor is mounted on a horizontal platform at a predetermined adjustable distance from the axis of rotation of the controlled body so that its laser beam hits the contour of the controlled cross section of the body above the jaws of the clamp.

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