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CN110100548B - Accurate positioning method for single-track type fertilizer applicator - Google Patents

Accurate positioning method for single-track type fertilizer applicator Download PDF

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CN110100548B
CN110100548B CN201910529698.9A CN201910529698A CN110100548B CN 110100548 B CN110100548 B CN 110100548B CN 201910529698 A CN201910529698 A CN 201910529698A CN 110100548 B CN110100548 B CN 110100548B
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potentiometer
track
resistance
meter
value
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CN110100548A (en
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田光兆
顾宝兴
林相泽
李�和
王海青
周俊
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Nanjing Agricultural University
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    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01C—PLANTING; SOWING; FERTILISING
    • A01C15/00—Fertiliser distributors
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01C—PLANTING; SOWING; FERTILISING
    • A01C23/00—Distributing devices specially adapted for liquid manure or other fertilising liquid, including ammonia, e.g. transport tanks or sprinkling wagons
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/004—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring coordinates of points

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  • Life Sciences & Earth Sciences (AREA)
  • Soil Sciences (AREA)
  • Environmental Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Water Supply & Treatment (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Lifting Devices For Agricultural Implements (AREA)
  • Fertilizing (AREA)

Abstract

本发明涉及一种单轨道式施肥机精准定位方法，包括单条直线金属材质轨道和施肥机，该施肥机底部引出一根金属电极，使所述轨道形成轨阻I和轨阻II，并与两组电位器、电阻和毫安表分别构成两组阻抗桥电路。通过调节各阻抗桥电路中的电位器，获得最小电流时的电位器输出值，再通过计算获得轨阻I和轨阻II的电阻值，最后，根据各段轨阻的阻值计算获得施肥机所在点的坐标值，从而，有效解决了在不通过GPS的情况下，精确定位施肥机的问题，提高了使用的便捷性，并可使定位更精准。

Figure 201910529698

The invention relates to a method for precise positioning of a single-track type fertilizer spreader. The group potentiometer, resistance and milliampere respectively constitute two groups of impedance bridge circuits. By adjusting the potentiometer in each impedance bridge circuit, the output value of the potentiometer at the minimum current is obtained, and then the resistance values of rail resistance I and rail resistance II are obtained by calculation. Finally, the fertilizer applicator is obtained by calculating the resistance value of each section of rail resistance. Therefore, the problem of accurately positioning the fertilizer applicator without GPS is effectively solved, the convenience of use is improved, and the positioning can be more accurate.

Figure 201910529698

Description

Accurate positioning method for single-track type fertilizer applicator
Technical Field
The invention relates to a control method of agricultural machinery, in particular to a control method of a fertilizer applicator, and specifically relates to a precise positioning method of a single-track type fertilizer applicator.
Background
The trunk and the canopy of the dwarf and close-planted fruit tree are short, and the row spacing and the plant spacing are small. Because the space is narrow and small, the fertilization machinery of traditional manual driving can't carry the fertilizer can and get into inside the orchard and fertilize the operation. Therefore, an automatic rail fertilizer applicator is required to replace manual operation. Most of the existing fertilizer applicators are positioned by satellites. However, because the crown of the fruit tree blocks satellite signals, the traditional RTK-GPS positioning cannot be generally used in an orchard, and improvement is urgently needed.
Disclosure of Invention
The invention aims to provide a precise positioning method of a single-track type fertilizer applicator, aiming at the defects of the prior art, which can quickly position the coordinates of the fertilizer applicator on a track, is simple to realize and high in accuracy and is not influenced by temperature.
The technical scheme of the invention is as follows:
a precise positioning method of a single-track type fertilizer applicator comprises a single linear metal track and the fertilizer applicator, wherein the fertilizer applicator is arranged on the track and moves along the track; a metal electrode is led out from the bottom of the fertilizer applicator and is electrically contacted with the track; the fertilizer applicator divides the track into two sections at the position on the track, and a track resistance I and a track resistance II are correspondingly formed; the rail resistor I, the potentiometer I, the resistor I, the milliammeter I and the power supply are connected to form an impedance bridge circuit I; the rail resistor II, the potentiometer II, the resistor II, the milliammeter II and a power supply are connected to form an impedance bridge circuit II; the positioning method comprises the following steps:
1) determining the absolute coordinates of the two ends of the rail by means of a measuring tool: head end A (x)1，y1) And tail end B (x)2，y2) And calculating the length L of the track;
2) a fertilizer applicator is arranged on the track, and the position point of the fertilizer applicator on the track is P; installing an impedance bridge circuit I and an impedance bridge circuit II; wherein: track resistance I is RxThe track resistance II is RyThe potentiometer I is Rc1The potentiometer II is Rc2The resistance I is R1The resistance II is R2The power supply is 5V;
3) the industrial personal computer sends out a control instruction to gradually increase the output resistance value of the potentiometer I from 0 to R1+R2Step length is 0.1 omega, and refreshing frequency is 10 Hz; meanwhile, the current value of the milliammeter I is synchronously read through an industrial personal computer, and the refreshing frequency is 10 Hz; recording the output value R of the potentiometer I when the value of the milliammeter I is minimumc1f；
4) The reverse operation is performed to make the output resistance of the potentiometer I from R1+R2Continuously decreasing until 0; simultaneously, synchronously reading the current value of the milliammeter I through an industrial personal computer; recording the output value R of the potentiometer I when the value of the milliammeter I is minimumc1b；
5) Calculated as Rx＝(Rc1f+Rc1b)/2；
6) The industrial personal computer sends out a control instruction to gradually increase the output resistance value of the potentiometer II from 0 to R1+R2Step length is 0.1 omega, and refreshing frequency is 10 Hz; meanwhile, the current value of the milliammeter II is synchronously read through an industrial personal computer, and the refreshing frequency is 10 Hz; recording the output value R of the potentiometer II when the value of the milliammeter II is minimumc2f；
7) The reverse operation is performed, so that the output resistance value of the potentiometer II is from R1+R2Continuously decreasing until 0; meanwhile, the current value of the milliammeter II is synchronously read through an industrial personal computer; recording the output value R of the potentiometer II when the value of the milliammeter II is minimumc2b；
8) Calculated as Ry＝(Rc2f+Rc2b)/2；
9) Calculating the distance from the point P to the point A: PA | ═ Rx/(Rx+Ry)×L；
10) Converting P to coordinates:
Figure BDA0002099335030000021
further, the potentiometer I and the potentiometer II are both digital potentiometers; and the milliammeter I and the milliammeter II are both digital milliammeters.
Further, the potentiometer I, the potentiometer II, the milliammeter I and the milliammeter II are provided with RS485 bus interfaces and are respectively connected to an industrial personal computer.
The invention has the beneficial effects that:
the invention has the advantages of reasonable design, simple structure, convenient control, simple realization, high accuracy and no influence of temperature, and can quickly position the coordinates of the fertilizer applicator on the track.
Drawings
FIG. 1 is a schematic diagram of the electrical connection of the present invention.
Wherein: rx-a track resistance I; ry-a track resistance II; r1-a resistance I; r2-a resistance II; rc1-a potentiometer I; rc2-a potentiometer II; mA1-milliammeter I; mA2Milliammeter II.
Detailed Description
The invention is further described below with reference to the figures and examples.
As shown in fig. 1.
A single-track type fertilizer applicator system comprises a single straight-line metal track and a fertilizer applicator, wherein the fertilizer applicator is arranged on the track and moves along the track; a metal electrode is led out from the bottom of the fertilizer applicator and is electrically contacted with the track; the fertilizer applicator divides the track into two sections at the position on the track, and a track resistance I and a track resistance II are correspondingly formed; the rail resistor I, the potentiometer I, the resistor I, the milliammeter I and the power supply are connected to form an impedance bridge circuit I; the rail resistor II, the potentiometer II, the resistor II, the milliammeter II and a power supply are connected to form an impedance bridge circuit II. The potentiometer I and the potentiometer II are both digital potentiometers; and the milliammeter I and the milliammeter II are both digital milliammeters. And the potentiometer I, the potentiometer II, the milliammeter I and the milliammeter II are respectively provided with an RS485 bus interface and are respectively connected to an industrial personal computer.
The invention discloses a precise positioning method of a single-track fertilizer applicator, which comprises the following steps:
1) determining the absolute coordinates of the two ends of the rail by means of a measuring tool: head end A (x)1，y1) And tail end B (x)2，y2) And calculating the length L of the track;
2) a fertilizer applicator is arranged on the track, and the position point of the fertilizer applicator on the track is P; installing an impedance bridge circuit I and an impedance bridge circuit II; wherein: track resistance I is RxThe track resistance II is RyThe potentiometer I is Rc1The potentiometer II is Rc2The resistance I is R1The resistance II is R2The power supply is 5V;
3) passing toolThe control machine sends out a control command to gradually increase the output resistance of the potentiometer I from 0 to R1+R2Step length is 0.1 omega, and refreshing frequency is 10 Hz; meanwhile, the current value of the milliammeter I is synchronously read through an industrial personal computer, and the refreshing frequency is 10 Hz; recording the output value R of the potentiometer I when the value of the milliammeter I is minimumc1f；
4) The reverse operation is performed to make the output resistance of the potentiometer I from R1+R2Continuously decreasing until 0; simultaneously, synchronously reading the current value of the milliammeter I through an industrial personal computer; recording the output value R of the potentiometer I when the value of the milliammeter I is minimumc1b；
5) Calculated as Rx＝(Rc1f+Rc1b)/2；
6) The industrial personal computer sends out a control instruction to gradually increase the output resistance value of the potentiometer II from 0 to R1+R2Step length is 0.1 omega, and refreshing frequency is 10 Hz; meanwhile, the current value of the milliammeter II is synchronously read through an industrial personal computer, and the refreshing frequency is 10 Hz; recording the output value R of the potentiometer II when the value of the milliammeter II is minimumc2f；
7) The reverse operation is performed, so that the output resistance value of the potentiometer II is from R1+R2Continuously decreasing until 0; meanwhile, the current value of the milliammeter II is synchronously read through an industrial personal computer; recording the output value R of the potentiometer II when the value of the milliammeter II is minimumc2b；
8) Calculated as Ry＝(Rc2f+Rc2b)/2；
9) Calculating the distance from the point P to the point A: PA | ═ Rx/(Rx+Ry)×L；
10) Converting P to coordinates:
Figure BDA0002099335030000031
specifically, the coordinates of point A, B are: a (x)1＝10.00，y1＝10.00)、B(x2＝96.60，y260.00). The coordinate of the AB point can be acquired by raising the RTK-GPS antenna, and the coordinate does not change after being acquired; the track length L is calculated to be 100.00 m.
Let R1＝R2R is 100 Ωc1f＝25.6Ω，Rc1b24.8 Ω, and further Rx＝(Rc1f+Rc1b)/2＝25.2Ω。
The same can be obtained: rc2f＝45.0Ω，Rc2b45.2 Ω, and further Ry＝(Rc2f+Rc2b)/2＝45.1Ω。
Then there are: PA | ═ Rx/(Rx+Ry)×L＝25.2/(25.2+45.1)×100＝35.85m。
The P point index is solved from the mathematical relationship as:
Figure BDA0002099335030000032
the parts not involved in the present invention are the same as or can be implemented using the prior art.

Claims (3)

1.一种单轨道式施肥机精准定位方法，包括单条直线金属材质轨道和施肥机，该施肥机安装在所述轨道上，并沿该轨道移动；其特征是：所述施肥机底部引出一根金属电极，该金属电极与所述轨道电气接触；所述施肥机在所述轨道上的位置将所述轨道分为两段，对应的形成轨阻I和轨阻II；该轨阻I和电位器I、电阻I、毫安表I以及电源连接成阻抗桥电路I；该轨阻II和电位器II、电阻II、毫安表II以及电源连接成阻抗桥电路II；所述定位方法包括以下步骤：1. A single-track type fertilizer spreader precise positioning method, comprising a single linear metal track and a fertilizer spreader, the fertilizer spreader is installed on the track, and moves along the track; it is characterized in that: the bottom of the fertilizer spreader leads out a A metal electrode, which is in electrical contact with the track; the position of the fertilizer applicator on the track divides the track into two sections, correspondingly forming track resistance I and track resistance II; the track resistance I and Potentiometer I, resistor I, milliamp meter I and power supply are connected to form an impedance bridge circuit I; the rail resistance II, potentiometer II, resistor II, mA meter II and power supply are connected to form an impedance bridge circuit II; the positioning method includes: The following steps: 1)通过测量工具确定轨道两端的绝对坐标：首端A(x1，y1)和尾端B(x2，y2)，并计算轨道长度L；1) Determine the absolute coordinates of both ends of the track by measuring tools: the head end A (x 1 , y 1 ) and the tail end B (x 2 , y 2 ), and calculate the track length L; 2)在轨道上安装施肥机，其位于所述轨道上的位置点为P；安装阻抗桥电路I和阻抗桥电路II；其中：轨阻I为Rx，轨阻II为Ry，电位器I为Rc1，电位器II为Rc2，电阻I为R1，电阻II为R2，电源为5V；所述R1＝R2；2) Install the fertilizer applicator on the track, and its position on the track is P; install the impedance bridge circuit I and the impedance bridge circuit II; wherein: the rail resistance I is R x , the rail resistance II is R y , and the potentiometer I is R c1 , potentiometer II is R c2 , resistance I is R 1 , resistance II is R 2 , and the power supply is 5V; the R 1 =R 2 ; 3)通过工控机发出控制指令，使电位器I的输出阻值由0逐渐增大至R1+R2，步长0.1Ω，刷新频率10Hz；同时，通过工控机同步读取毫安表I的电流值，刷新频率10Hz；记录下毫安表I数值最小时的电位器I的输出值Rc1f；3) Issue a control command through the industrial computer to gradually increase the output resistance of the potentiometer I from 0 to R 1 +R 2 , with a step size of 0.1Ω and a refresh frequency of 10Hz; at the same time, read the milliamp meter I synchronously through the industrial computer The current value, the refresh frequency is 10Hz; record the output value R c1f of the potentiometer I when the value of the milliamp meter I is the smallest; 4)反向操作，令电位器I的输出阻值由R1+R2持续减小，直至0；同时，通过工控机同步读取毫安表I的电流值；记录下毫安表I数值最小时的电位器I的输出值Rc1b；4) Reverse operation, make the output resistance value of potentiometer I continuously decrease from R 1 +R 2 until 0; at the same time, read the current value of mA meter I synchronously through the industrial computer; record the value of mA meter I The output value R c1b of the potentiometer I at the minimum time; 5)计算得Rx＝(Rc1f+Rc1b)/2；5) Calculated R x =(R c1f +R c1b )/2; 6)通过工控机发出控制指令，使电位器II的输出阻值由0逐渐增大至R1+R2，步长0.1Ω，刷新频率10Hz；同时，通过工控机同步读取毫安表II的电流值，刷新频率10Hz；记录下毫安表II数值最小时的电位器II的输出值Rc2f；6) Issue control commands through the industrial computer to gradually increase the output resistance of the potentiometer II from 0 to R 1 +R 2 , the step size is 0.1Ω, and the refresh frequency is 10Hz; at the same time, the milliamp meter II is read synchronously through the industrial computer. The current value, the refresh frequency is 10Hz; record the output value R c2f of the potentiometer II when the mA meter II value is the smallest; 7)反向操作，令电位器II的输出阻值由R1+R2持续减小，直至0；同时，通过工控机同步读取毫安表II的电流值；记录下毫安表II数值最小时的电位器II的输出值Rc2b；7) Reverse operation, make the output resistance of potentiometer II continuously decrease from R 1 +R 2 to 0; at the same time, read the current value of mA meter II synchronously through the industrial computer; record the value of mA meter II The output value R c2b of the potentiometer II at the minimum time; 8)计算得Ry＝(Rc2f+Rc2b)/2；8) Calculated R y =(R c2f +R c2b )/2; 9)计算得P点距离A点的距离：|PA|＝Rx/(Rx+Ry)×L；9) Calculate the distance between point P and point A: |PA|=R x /(R x +R y )×L; 10)将P转换为坐标：
Figure FDA0003160486150000011
10) Convert P to coordinates:
Figure FDA0003160486150000011
 2.根据权利要求1所述的单轨道式施肥机精准定位方法，其特征是：所述电位器I和电位器II均为数字电位器；所述毫安表I和毫安表II均为数字毫安表。2. single-track type fertilizer spreader precise positioning method according to claim 1, is characterized in that: described potentiometer I and potentiometer II are digital potentiometers; Described milliamp meter I and milliamp meter II are both. Digital mA meter. 3.根据权利要求1所述的单轨道式施肥机精准定位方法，其特征是：所述电位器I、电位器II、毫安表I和毫安表II均具有RS485总线接口，分别连接到工控机。3. single-track type fertilizer spreader precise positioning method according to claim 1 is characterized in that: described potentiometer I, potentiometer II, milliamp meter I and milliampere II all have RS485 bus interface, are connected to respectively. Industrial computer.
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