CN112189387A - Centrifugal ridging seeder and seeding quantity feedback control method - Google Patents
Centrifugal ridging seeder and seeding quantity feedback control method Download PDFInfo
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- CN112189387A CN112189387A CN202010886471.2A CN202010886471A CN112189387A CN 112189387 A CN112189387 A CN 112189387A CN 202010886471 A CN202010886471 A CN 202010886471A CN 112189387 A CN112189387 A CN 112189387A
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- A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
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- A01B49/00—Combined machines
- A01B49/04—Combinations of soil-working tools with non-soil-working tools, e.g. planting tools
- A01B49/06—Combinations of soil-working tools with non-soil-working tools, e.g. planting tools for sowing or fertilising
- A01B49/065—Combinations of soil-working tools with non-soil-working tools, e.g. planting tools for sowing or fertilising the soil-working tools being actively driven
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Abstract
The invention discloses a centrifugal ridging seeder and a seeding quantity feedback control method, wherein the relation S ═ f (n) between the rotating speed of a seeding unit and the number of seeding grains in unit time is determined through tests according to S0＝f(n0) Calculating the initial seed-metering device rotating speed S0And drives the centrifugal seed sowing device to rotate and calculate the current driving speed V of the ridgerMeasuring2 pi rA/a according to the current driving speed V of the ridgerMeasuringObtaining the seed number n of the current travelling speed of the ridgerTheory of things＝VMeasuring/l0Then obtaining S from S ═ f (n)Theory of thingsMeasuring the number n of the seed-metering grainsMeasuringB, mixing n withMeasuringAnd the theoretical seed number nTheory of thingsComparing; the running speed of the seeder and the seed feeding amount of the seed feeding port are detected by setting the seed distance, and the rotating speed of the stepping motor is changed in real time according to the relation between the working rotating speed of the seed sowing device and the seed feeding amount of the seed sowing in unit time, so that the precision control of the sowing amount of the centrifugal ridging seeder is realized, and the seeding is more uniform.
Description
Technical Field
The invention relates to the technical field of precision seeding in agricultural machinery, in particular to a centrifugal ridging seeder and a seeding quantity feedback control method.
Background
Seeds having an average particle size of less than 3mm such as green vegetables, rape, and pakchoi are called small-particle-size seeds. The small-particle size seed crops have a very important position in the planting of crops in China, particularly in the planting of vegetable crops, and the demand of green vegetables is increasingly large along with the favor of people on green healthy diet. Traditional vegetables seeding mode mainly uses the manual work to broadcast and sow as the owner, and this kind of seeding mode not only consumes a large amount of fine varieties, and the later stage still need carry out thinning and final singling moreover, and the cost labour is many, inefficiency, great increase manufacturing cost. At the present stage, a mechanical sowing technology is gradually popularized in China, and a precision sowing technology is that a certain number of seeds are sown into soil with a certain depth according to a certain row spacing and a certain grain spacing, and meanwhile, a proper amount of wet soil is covered on the seeds and is properly compacted, so that the seeds are saved, the uniform row spacing can be ensured, a large amount of manpower and material resources are saved, the production efficiency is greatly improved, and the method is a necessary trend of modern agricultural production development.
The stable volume of broadcasting of seeder is key performance index, and traditional seeder adopts the land wheel, through chain drive or axle drive seed metering ware, realizes that seed metering ware operating speed and seeder forward velocity keep invariable, nevertheless has the land wheel to skid, the drive power is not enough, transmission route is complicated, volume of broadcasting adjusts inconvenient scheduling problem.
The invention is a Chinese patent with application number '201610273020.5', named as 'centrifugal small-grain-size seed precision seeder and seeding rate control method thereof', which uses a small miniature walking tractor as matching power, adopts a centrifugal seed sowing device, drives a seed sowing device to sow seeds by a direct current motor, monitors the advancing speed in real time by a rotating speed sensor arranged on a tractor ground wheel, establishes a feedback signal, controls the armature voltage of the driving motor of the seed sowing device, thereby controlling the working rotating speed of the seed sowing device and realizing the matching of the seeding rate and the advancing speed variation of the seeder; however, in the operation process of the seeder, the seeding amount of the seeding apparatus may be disturbed along with the factors such as the change of the size of the seeding seeds and the change of the number of the seeds in the seeding apparatus, the actual seeding amount is different from the ideal seeding amount, and the control system cannot sense the actual seeding amount of the seeder, lacks feedback information of the seeding amount and cannot realize accurate adjustment and control of the seeding amount.
Disclosure of Invention
The invention aims to provide a centrifugal ridging seeder and a seeding quantity feedback control method aiming at the defects of the technology, so as to realize the precise control of the seeding quantity of the centrifugal ridging seeder.
In order to achieve the aim, the seeding quantity feedback control method of the centrifugal ridging seeder comprises the following steps:
1) the relation S ═ f (n) between the rotation speed of the seed metering device and the number of the seed metering grains in unit time is determined through tests;
2) initializing before seeding operation and setting theoretical grain distance l0；
3) During the sowing operation, when the sowing machine is at the preset speed V0Run according to n0＝V0/l0Calculating the initial seed number n of the seeds in unit time0Then according to S0＝f(n0) Calculating the initial seed-metering device rotating speed S0And drives the centrifugal seeding apparatus to rotate;
4) when the speed of the ridger changes, a rotating speed disc arranged on a travelling wheel shaft of the ridger rotates along with the advancing of the ridger; when the magnetic steel passes through the Hall sensor, the Hall sensor outputs low level, the low level output signal is transmitted to the control unit, the control unit acquires the low level in unit time and counts the low level, and when the count in unit time is a, the current is obtained at the momentTraveling speed V of ridger Measuring2 pi rA/a, wherein r is the radius of the ground wheel of the ridger, A is the number of pulses in unit time, and a is the number of magnetic steels;
5) when V isMeasuringIs not equal to V0Skipping to the step 3) according to the current driving speed V of the ridgerMeasuringObtaining the seed number n of the current travelling speed of the ridgerTheory of things＝VMeasuring/l0Then obtaining S from S ═ f (n)Theory of thingsThe control unit transmits the rotation speed information of the seed sowing device to the motor driving signal output end, so that the stepping motor drives the motor to rotate by STheory of thingsRotating;
6) when the centrifugal seed sowing device rotates at the rotating speed STheory of thingsWhen the device works, the photoelectric sensor arranged at the seed feeding port of the centrifugal seed sowing device is used for detecting the seed sowing amount of seeds, when the seeds fall, the photoelectric sensor outputs low level, the photoelectric sensor transmits the seed pulse number b obtained in unit time to the control unit for counting, and the seed sowing number n is measuredMeasuringB, mixing n withMeasuringAnd the theoretical seed number nTheory of thingsComparing;
if n isMeasuringGreater than nTheory of thingsThe step motor speed S is equal to STheory of things-K(nMeasuring-nTheory of things) Reducing the rotation speed of the stepping motor to nMeasuring＝nTheory of things(ii) a If n isMeasuringLess than nTheory of thingsThe step motor speed S is equal to STheory of things+K(nTheory of things-nMeasuring) Increasing the rotation speed of the stepping motor to nMeasuring＝nTheory of things。
Further, in the step 1), the corresponding number of seed metering grains per unit time at different rotation speeds is obtained according to a test, a plurality of groups of data of rotation speed-number of seed metering grains are obtained, and a linear relation between the working rotation speed of the seed metering device and the number of seed metering grains per unit time, that is, S ═ cn + d, is obtained through fitting, wherein c and d are fitting parameters.
The centrifugal ridging seeder with the seeding rate feedback control function comprises a ridging machine, a stepping motor, a land wheel and a seeding device, wherein the stepping motor is connected with a rotating shaft of the seeding device; the speed measuring device comprises a Hall sensor, a rotating speed disc and magnetic steel, the magnetic steel is uniformly arranged on the rotating speed disc, the rotating speed disc is fixed on a land wheel, and the Hall sensor is arranged on a gearbox of the seeder; the seeding quantity detection device comprises a photoelectric sensor which is arranged at a seed feeding port of the seed sowing device;
the output end of the Hall sensor is connected with the rotating speed signal input end of the control unit, the stepping motor is connected with the motor driving signal output end of the control unit, and the output end of the photoelectric sensor is connected with the seeding quantity detection input end of the control unit.
Compared with the prior art, the invention has the following advantages: the seeding quantity feedback control method of the centrifugal ridging seeder detects the running speed of the seeder and the seed feeding quantity of the seed feeding port by setting the grain distance, changes the rotating speed of the stepping motor in real time according to the relation between the working rotating speed of the seed sowing device and the seed feeding quantity per unit time, realizes the precise control of the seeding quantity of the centrifugal ridging seeder and ensures that the seeding is more uniform.
Drawings
FIG. 1 is a schematic structural view of the centrifugal ridging seeder of the present invention.
The components in the figures are numbered as follows: the ridging machine comprises a ridging machine 1, a control unit 2, a Hall sensor 3, a rotating speed disc 4, magnetic steel 5, a photoelectric sensor 6, a seed sowing device 7, a seed throwing port 8 and traveling wheels 9.
Detailed Description
The invention is described in further detail below with reference to the figures and the specific embodiments.
The seeding quantity feedback control method of the centrifugal ridging seeder comprises the following steps:
1) the relation between the rotating speed of the seed sowing device and the number of the seed sowing grains in unit time is determined through tests: s ═ f (n)
Obtaining the corresponding number of seed metering grains in unit time at different rotating speeds according to a test, obtaining a plurality of groups of data of rotating speed and the number of seed metering grains, and fitting to obtain a linear relation of the working rotating speed of the seed metering device and the number of seed metering grains in unit time, namely S ═ cn + d, wherein c and d are fitting parameters;
2) initializing before seeding operation and setting theoretical grain distance l0；
3) During the sowing operation, when the sowing machine is usedSet velocity V0Run according to n0＝V0/l0Calculating the initial seed number n of the seeds in unit time0Then according to S0＝f(n0) Calculating the initial seed-metering device rotating speed S0And drives the centrifugal seeding apparatus to rotate;
4) when the speed of the ridger changes, a rotating speed disc arranged on a travelling wheel shaft of the ridger rotates along with the advancing of the ridger; when the magnetic steel passes through the Hall sensor, the output of the Hall sensor is low level, a low level output signal is transmitted to the rotating speed signal input end and then transmitted to the control unit, the control unit captures the low level in unit time and counts the low level, and when the count in unit time is a, the current traveling speed V of the ridger is obtained at the moment Measuring2 pi rA/a, wherein r is the radius of the land wheel of the ridger, A is the number of pulses in unit time, and a is the number of magnetic steels;
5) when V isMeasuringIs not equal to V0Skipping to the step 3) according to the current driving speed V of the ridgerMeasuringObtaining the seed number n of the current travelling speed of the ridgerTheory of things＝VMeasuring/l0Then obtaining S from S ═ f (n)Theory of thingsThe control unit transmits the rotation speed information of the seed sowing device to the motor driving signal output end, so that the stepping motor drives the motor to rotate by STheory of thingsRotating;
6) when the centrifugal seed sowing device rotates at the rotating speed STheory of thingsWhen the seed dropping device works, the actual seeding quantity is different from the ideal seeding quantity due to the disturbance of factors such as the seed discharging quantity of the seed metering device, the change of the seed quantity in the seed metering device and the like along with the change of the size of the sown seeds, the seed discharging quantity is detected by the photoelectric sensor arranged at the seed dropping port of the centrifugal seed metering device, when the seeds fall, the seed discharging quantity is output to be a low level, the photoelectric sensor transmits the seed pulse number b obtained in unit time to the seeding quantity detection input end through a lead and then transmits the seed pulse number b to the control unit for counting, and the seed discharging quantityMeasuringB, mixing n withMeasuringAnd the theoretical seed number nTheory of thingsComparing;
if n isMeasuringGreater than nTheory of thingsThe step motor speed S is equal to STheory of things-K(nMeasuring-nTheory of things) Stepping motorRotating speed up to nMeasuring＝nTheory of things(ii) a If n isMeasuringLess than nTheory of thingsThe step motor speed S is equal to STheory of things+K(nTheory of things-nMeasuring) Increasing the rotation speed of the stepping motor to nMeasuring＝nTheory of thingsSo that the rotating speed of the stepping motor meets the theoretical moment l0Seed number nTheory of thingsThe feedback adjustment of the seed discharging amount is realized; wherein K is a proportionality coefficient.
The centrifugal ridging seeder shown in fig. 1 comprises a ridging machine 1, a stepping motor, a land wheel 9, a seed sowing device 7, a speed measuring device, a sowing quantity detecting device and a control unit 2, wherein the stepping motor is connected with a rotating shaft of the seed sowing device 7. The speed measuring device comprises a Hall sensor 3, a rotating speed disc 4 and magnetic steel 5, wherein the magnetic steel 5 is uniformly arranged on the rotating speed disc 4, the rotating speed disc 4 is fixed on a land wheel 9, and the Hall sensor 3 is arranged on a gearbox of the seeder; the seeding quantity detection device comprises a photoelectric sensor 6, and the photoelectric sensor 6 is arranged at a seed feeding port 8 of a seed sowing device 7 and is used for detecting the seed sowing grain number of seeds.
The output end of the Hall sensor 3 is connected with the rotating speed signal input end of the control unit 2, the stepping motor is connected with the motor driving signal output end of the control unit 2, and the output end of the photoelectric sensor 6 is connected with the seeding quantity detection input end of the control unit 2.
The seeding quantity feedback control method of the centrifugal ridging seeder detects the running speed of the seeder and the seed feeding quantity of the seed feeding port by setting the grain distance, changes the rotating speed of the stepping motor in real time according to the relation between the working rotating speed of the seed sowing device and the seed feeding quantity per unit time, realizes the precise control of the seeding quantity of the centrifugal ridging seeder and ensures that the seeding is more uniform.
Claims (3)
1. A seeding quantity feedback control method of a centrifugal ridging seeder is characterized by comprising the following steps: the feedback control method comprises the following steps:
1) the relation S ═ f (n) between the rotation speed of the seed metering device and the number of the seed metering grains in unit time is determined through tests;
2) initializing before seeding operation and setting theoretical grain distance l0；
3) During the sowing operation, when the sowing machine is presetVelocity V0Run according to n0＝V0/l0Calculating the initial seed number n of the seeds in unit time0Then according to S0＝f(n0) Calculating the initial seed-metering device rotating speed S0And drives the centrifugal seeding apparatus to rotate;
4) when the speed of the ridger changes, a rotating speed disc arranged on a walking wheel shaft of the ridger rotates along with the advancing of the ridger; when the magnetic steel passes through the Hall sensor, the Hall sensor outputs low level, the low level output signal is transmitted to the control unit, the control unit acquires the low level in unit time and counts the low level, and when the count in unit time is a, the current traveling speed V of the ridger is obtained at the momentMeasuring2 pi rA/a, wherein r is the radius of the ground wheel of the ridger, A is the number of pulses in unit time, and a is the number of magnetic steels;
5) when V isMeasuringIs not equal to V0Skipping to the step 3) according to the current driving speed V of the ridgerMeasuringObtaining the seed number n of the current travelling speed of the ridgerTheory of things＝VMeasuring/l0Then obtaining S from S ═ f (n)Theory of thingsThe control unit transmits the rotation speed information of the seed sowing device to the motor driving signal output end, so that the stepping motor drives the motor to rotate by STheory of thingsRotating;
6) when the centrifugal seed sowing device rotates at the rotating speed STheory of thingsWhen the device works, the photoelectric sensor arranged at the seed feeding port of the centrifugal seed sowing device is used for detecting the seed sowing amount of seeds, when the seeds fall, the photoelectric sensor outputs low level, the photoelectric sensor transmits the seed pulse number b obtained in unit time to the control unit for counting, and the seed sowing number n is measuredMeasuringB, mixing n withMeasuringAnd the theoretical seed number nTheory of thingsComparing;
if n isMeasuringGreater than nTheory of thingsThe step motor speed S is equal to STheory of things-K(nMeasuring-nTheory of things) Reducing the rotation speed of the stepping motor to nMeasuring＝nTheory of things(ii) a If n isMeasuringLess than nTheory of thingsThe step motor speed S is equal to STheory of things+K(nTheory of things-nMeasuring) Increasing the rotation speed of the stepping motor to nMeasuring＝nTheory of things。
2. The seeding quantity feedback control method of the centrifugal ridging seeder as claimed in claim 1, characterized in that: in the step 1), the corresponding number of the seed metering grains per unit time at different rotating speeds is obtained according to a test, a plurality of groups of data of rotating speed and the number of the seed metering grains are obtained, and a linear relation between the working rotating speed of the seed metering device and the number of the seed metering grains per unit time, namely S ═ cn + d, is obtained through fitting, wherein c and d are fitting parameters.
3. A centrifugal ridging seeder with the seeding quantity feedback control of the right 1 comprises a ridging machine (1), a stepping motor, a land wheel (9) and a seeding device (7), wherein the stepping motor is connected with a rotating shaft of the seeding device (7); the method is characterized in that: the seeding machine is characterized by further comprising a speed measuring device, a seeding quantity detecting device and a control unit (2), wherein the speed measuring device comprises a Hall sensor (3), a rotating speed disc (4) and magnetic steel (5), the magnetic steel (5) is uniformly placed on the rotating speed disc (4), the rotating speed disc (4) is fixed on a land wheel (9), and the Hall sensor (3) is mounted on a gearbox of the seeding machine; the seeding quantity detection device comprises a photoelectric sensor (6), and the photoelectric sensor (6) is arranged on a seed feeding port (8) of a seed sowing device (7);
the output end of the Hall sensor (3) is connected with the rotating speed signal input end of the control unit (2), the stepping motor is connected with the motor driving signal output end of the control unit (2), and the output end of the photoelectric sensor (6) is connected with the seeding quantity detection input end of the control unit (2).
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113039901A (en) * | 2021-03-30 | 2021-06-29 | 华中农业大学 | Digital seed sowing device based on seed sowing frequency feedback and seed sowing control method |
| CN114731789A (en) * | 2022-04-22 | 2022-07-12 | 湖州职业技术学院(湖州广播电视大学)(湖州社区大学) | Multifunctional intelligent control rice precision seed sowing device |
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