Single-touch-rod dual-axis position sensing device

Abstract

The application discloses a single-touch-rod double-shaft position detection device, which comprises a touch rod, a reset spring, an angular displacement sensor and a limiting block. The touch rod rotates around a joint point. The touch rod is directly connected with the angular displacement sensor or is connected with the angular displacement sensor through a transmission mechanism. The angular displacement sensor is used for acquiring the swing angle of the touch rod. The reset spring is arranged on one side of the swing route of the touch rod. The limiting block is arranged on the opposite side of the reset spring of the swing route of the touch rod. The initial position of the reset spring and the limiting block when the reset spring is pushed and the limiting block is limited has an inclination angle with the advancing direction. The reset spring makes the touch rod always contact with the measured object. The application has simple structure and can accurately acquire the transverse and longitudinal distances between the vegetables and the detection device, thereby providing a basis for the row operation of the harvesting device.

Description

TECHNICAL FIELD

[0001] The present application relates to a position detecting device, in particular a single-touching-rod double-axis position detecting device. BACKGROUND

[0002] The stem and leaf vegetables need to be separated from the soil by cutting device, then orderly transported and collected, so that the stem and leaf vegetables are aligned with the clamping and transporting device during the orderly harvesting, which is the basic requirement for successful harvesting. However, due to the random factors such as sowing, transplanting and growth of the vegetables, the growth positions of the vegetables are different, especially under the condition of multi-row planting, the operator cannot adjust the lateral position of the harvesting machine to align with each row of vegetables. Therefore, the existing stem and leaf vegetable harvesting machines basically expand the size of the feeding inlet and install a stirring mechanism, and adopt the method of cutting first and then transporting to adapt to the difference in growth position, but this also brings the problems of large and complex structure, which results in the shortage of suitable varieties. However, there are many varieties of stem and leaf vegetables in China, and the planting row spacing of some vegetables is small. Due to the low level of mechanization and the low degree of standardization of planting, the variation degree of the row spacing is large, which makes the existing measures unable to meet the demand of mechanized harvesting, so the stem and leaf vegetable harvesting machine capable of automatically aligning with the row is needed. However, due to the irregular growth of the vegetables, the leaf coverage, the interference of weeds and the dynamic operation of the harvesting machine, the methods such as visual image recognition, ultrasonic measurement and radar detection are easily disturbed and inaccurate, and the price is high. SUMMARY

[0003] The purpose of the present application is to overcome the shortcomings of the prior art, and to provide a single-touching-rod double-axis position detecting device which can measure the lateral and longitudinal distance between the vegetables and the detecting device after touching the vegetables, so as to provide the basis for the row operation of the harvesting device.

[0004] A single-touching-rod double-axis position detecting device, comprising a touching rod, a reset spring, an angle displacement sensor and a limiting block, the touching rod rotates around a hinged point, the touching rod is connected with the angle displacement sensor directly or through a transmission mechanism, the angle displacement sensor is used to obtain the swinging angle of the touching rod, the reset spring is arranged on one side of the swinging path of the touching rod, and the limiting block is arranged on the opposite side of the reset spring in the swinging path of the touching rod, the initial position and the advancing direction of the reset spring and the limiting block have an inclination angle, and the reset spring makes the touching rod always contact with the measured object.

[0005] After the angle displacement sensor of the single-touching-rod double-axis position detecting device obtains the swinging angle of the touching rod, the harvesting device can obtain the X-axis and Y-axis distances x and y between the hinged point of the touching rod and the contact point of the touched object, so as to obtain the specific position of the measured object, and the specific calculation method of the X-axis and Y-axis distances x and y between the hinged point of the touching rod and the contact point of the touched object is as follows:

[0006] When working, the detection device installed in the front part of the harvesting device advances with the harvester, the transverse distance between the measured object and the contact point of the touch rod is x, the longitudinal distance is y, the advancing speed of the detector is v x , the transverse moving speed is v y , the distance between the contact surface of the touch rod and the contact point is r, the angle between the touch rod and the advancing direction is α,

[0007] When the vegetable contacts the touch rod, according to the geometric relationship, the following can be obtained:

[0008] xcosα+ysinα=r……(1),

[0009] Deriving formula (1) with respect to time t, the following can be obtained:

[0010]

[0011] Let and since , formula (2) can be simplified as:

[0012]

[0013] According to formula (1) and formula (3), the following can be obtained:

[0014]

[0015] Since the detection device is installed in the front part of the harvesting device, the advancing speed v x and the transverse moving speed v y can be obtained by the driving device, and the distance r between the contact surface of the touch rod and the contact point is a fixed value of the structural parameter, so only the value of the angle α between the touch rod and the advancing direction needs to be obtained, and then the angular speed ω of the touch rod can be obtained according to the change rate of the angle α, and then the X-axis and Y-axis distances x and y between the contact point and the contact point can be obtained according to formula (4) and formula (5).

[0016] In order to improve the accuracy of the obtained distance between the measured object and the contact point, the average value can also be calculated by measuring multiple times:

[0017] Formula (4) and formula (5) are transformed into formula (6) and formula (7), and then the advancing displacement difference △X, the transverse displacement difference △Y, the touch rod angular displacement difference △α, and the average value of the touch rod rotation angle obtained by measuring twice can be obtained.

[0018]

[0019] The single-touch-rod double-axis position detection device is a pair of matched devices.

[0020] Because a single-touch dual-axis position detection device is used, it can only detect the position on the side in contact with the touch rod. Since different varieties of vegetables vary significantly in size, to more accurately detect the area occupied by the vegetable stem, two sets of single-touch dual-axis position detection devices (such as...) can be used. Figure 3 As shown in the figure, the positions of the two sides of the stem are obtained by the detection devices deployed on both sides of the harvesting device, thereby determining the position and size of the stem and providing data support for the lateral movement of the rowing device.

[0021] In summary, the present invention has the following advantages over the prior art:

[0022] The single-touch rod dual-axis position detection device of the present invention adopts a simple structure and can accurately obtain the lateral and longitudinal distances between the vegetables and the detection device, thereby providing a basis for the harvesting device to operate in rows. Attached Figure Description

[0023] Figure 1 This is a structural diagram of a single-touch rod dual-axis position detection device.

[0024] Figure 2 This is a simplified diagram illustrating the principle of obtaining the X-axis and Y-axis distances between the contact point of the contact rod and the contact point of the object being contacted.

[0025] Figure 3 This is a schematic diagram of the single-touch rod dual-axis position detection device of the present invention used in pairs. Detailed Implementation

[0026] The present invention will now be described in more detail with reference to the embodiments.

[0027] Example 1

[0028] A single-touch rod dual-axis position detection device consists of a touch rod 1, a return spring 2, an angular displacement sensor 3, and a limiting block 4. The touch rod can rotate around the hinge point. When the return spring 2 pushes and the limiting block 4 limits it, the initial position has an inclination angle with the forward direction. The touch rod can be directly connected to the angular displacement sensor or connected through a transmission mechanism. When the touch rod is touched and rotated, the angular displacement sensor connected to it can obtain the rotation angle of the touch rod. At the same time, the return spring can keep the touch rod in contact with the object being measured.

[0029] The specific principle is as follows: During operation, the detection device installed at the front of the harvesting device moves forward with the harvester. Let the lateral distance between the vegetable (the object being measured) 5 and the contact point of the contact rod be x, the longitudinal distance be y, and the forward speed of the detector be v. x The lateral velocity is v y The distance between the contact surface of the contact rod and the pivot point is r, and the angle between the contact rod and the forward direction is α. Figure 2 As shown;

[0030] When the vegetable comes into contact with the contact rod, according to geometric relationships, we can obtain:

[0031] xcosα+ysinα=r……(1),

[0032] Taking derivative of (1) with respect to time t, we have:

[0033]

[0034] Let and since (2) can be simplified as:

[0035]

[0036] From (1) and (3), we have:

[0037]

[0038] Since the detection device is installed in front of the harvesting device, the forward speed v x and the lateral speed v y can be obtained by the driving device, and the distance r between the contact surface of the touch rod and the twisting point is a fixed value of the structure parameter, so only the value of the angle α between the touch rod and the forward direction needs to be obtained, and then the angular velocity ω of the touch rod can be obtained according to the rate of change of α, and then the distances x and y between the contact point and the twisting point on the X-axis and Y-axis can be solved from (4) and (5).

[0039] Since the speed and angular velocity are displacement and angular displacement per unit time, and in measurement, the displacement is a direct measurement value, while the speed and angular velocity are calculated values. Therefore, in actual application, (4) and (5) are transformed into (6) and (7), and then the forward displacement difference △X, the lateral displacement difference △Y, the touch rod angular displacement difference △α, and the average value of the touch rod rotation angle can be obtained by applying the two simultaneous measurements, so that the average values of the distances x and y between the contact point and the twisting point on the X-axis and Y-axis in two measurements can be obtained.

[0040]

[0041] Since a single-touch rod double-axis position detection device is used, only the position on one side of the touch rod in contact can be detected. Since the sizes of different varieties of vegetables are quite different, in order to more accurately detect the area occupied by the vegetable stems, two sets of single-touch rod double-axis position detection devices (as shown in Figure 3 ) can be used to obtain the positions of the two sides of the stem by arranging the detection devices on both sides of the harvesting device, so as to determine the position and size of the stem and provide data support for the lateral movement of the row device.

[0042] The unstated parts of this embodiment are the same as the prior art.

Claims

1. A single-touch rod dual-axis position detection device, characterized in that: The device includes a contact rod, a return spring, an angular displacement sensor, and a limiting block. The contact rod rotates around the hinge point. The contact rod is either directly connected to the angular displacement sensor or connected to the angular displacement sensor through a transmission mechanism. The angular displacement sensor is used to obtain the swing angle of the contact rod. A return spring is set on one side of the swing path of the contact rod, and a limiting block is set on the opposite side of the return spring. The initial position of the contact rod when the return spring pushes and the limiting block limits it has an inclination angle with the forward direction. The return spring ensures that the contact rod is always in contact with the object being measured. After obtaining the swing angle of the contact rod using the single-contact rod dual-axis position detection device angular displacement sensor, the harvesting device can obtain the X-axis and Y-axis distances x and y between the contact point of the contact rod and the contact point of the object being measured, thereby obtaining the specific position of the object being measured. The specific calculation method for the X-axis and Y-axis distances x and y between the contact point of the contact rod and the contact point of the object being measured is as follows: Let x be the lateral distance between the object being measured and the contact point of the probe, y be the longitudinal distance, and v be the forward speed of the detector. x The lateral velocity is v y The distance between the contact surface of the contact rod and the pivot point is r, and the angle between the contact rod and the forward direction is α. When the object being measured comes into contact with the contact rod, according to geometric relationships, we can obtain: xcosα+ysinα=r……(1), Differentiating equation (1) with respect to time t, we get: make And because Then equation (2) can be simplified to: By combining equations (1) and (3), we can obtain:

2. The single-touch rod dual-axis position detection device according to claim 1, characterized in that: To improve the accuracy of the distance between the measured object and the joint point, the average value can be calculated from multiple measurements. Equations (4) and (5) are transformed into equations (6) and (7), and then the forward displacement difference ΔX, lateral displacement difference ΔY, contact rod angular displacement difference Δα, and average contact rod rotation angle obtained from two simultaneous measurements are applied. This yields the average distances along the X and Y axes between the contact point and the hinge point measured twice.

3. The single-touch rod dual-axis position detection device according to claim 2, characterized in that: The single-touch dual-axis position detection device is used in pairs.

Images