CN210946942U - Single GPS land leveler knife height control device - Google Patents
Single GPS land leveler knife height control device Download PDFInfo
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Abstract
The utility model discloses a single GPS land scraper height control device, wherein a GPS receiver is arranged at one end of a scraper of a land scraper and is used for receiving a current position height signal; the first azimuth angle sensor is arranged on a frame of the land leveler and used for detecting the rotation angle of the cutting blade around the transverse center line of the cutting blade of the land leveler; the second azimuth angle sensor is arranged on the scraper knife and used for detecting the rotation angle of the scraper knife around the center line of the vertical horizontal plane; the third azimuth angle sensor is arranged on a traction frame rotating disc of the land scraper and used for detecting the rotation angle of the scraper around the center line of the running direction of the land scraper; two ends of the scraper knife are respectively provided with a lifting oil cylinder, and the lifting oil cylinder adjusts the height of the scraper knife to a target value. The utility model discloses only adopt single GPS receiver, combine the azimuth sensor aided detection, realize the elevation control of high accuracy, this system only adopts a GPS receiver, greatly reduced GPS system application cost.
Description
Technical Field
The utility model relates to a building soil bases such as highway, railway, airport, pier, organic or inorganic binder stabilized soil bed course and basic unit field, more specifically relate to a single GPS's leveler elevation control device and system.
Background
A land leveler, as a multipurpose continuous operation type earth moving machine for land leveling and shaping work, plays an incomparable role in the leveling construction of a road bed. In order to ensure the construction flatness, greatly reduce the labor intensity of an operator and improve the construction efficiency, the land leveler system with the automatic elevation control function is an effective solution.
The existing height control systems mainly comprise two types, namely a two-dimensional height control system based on laser and a three-dimensional height control system based on a GPS. The principle of the GPS three-dimensional elevation control is as follows: and the double GPS mobile stations arranged at two ends of the cutting edge of the land leveler acquire the elevation of the cutting edge in real time, and the elevation is compared with the designed elevation, and the real-time accurate hydraulic valve controls and adjusts the action of the lifting oil cylinder so as to control the elevation. Because the GPS has the advantages of high precision, all-weather measurement and high anti-interference strength, the elevation can be accurately controlled in the elevation control process of the land leveler, and the precise leveling operation is realized. But it can be seen that a set of GPS three-dimensional elevation control system requires 2 GPS rover stations for operation, and a single GPS is more than one hundred thousand in price and expensive.
Patent CN1070468820 proposes an agricultural leveler control system based on double-antenna GNSS, and the system adopts double-GNSS to obtain the elevation of spiller both ends, combines the acceleration sensor that detects the horizontal angle of inclination of spiller to carry out the calibration of spiller gesture, through the action of controller control cylinder.
Patent CN107842050 proposes a manual-assisted automatic leveling system of a land leveler based on GPS-RTK, which adopts two GPS-RTKs and combines a shovel blade inclination angle sensor to position and automatically level a to-be-leveled surface with a longitudinal and transverse gradient.
The heights of the shoveling blades are monitored by adopting a double-GPS system, the actions of the oil cylinders are controlled, and the precise leveling operation is realized, however, the price of a single GPS is over one hundred thousand, the price is high, the application cost greatly exceeds the industrial expectation, and the large-scale application is difficult.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the technical problem who solves:
the land leveling technique to present GPS adopts two GPS sensors to detect the scraper blade elevation usually, and automatic land leveling operation is realized in the control cylinder action, and single GPS's price reaches more than one hundred thousand, and the price is expensive, and application cost is higher, is difficult to the problem of extensive application, the utility model aims at providing a leveler scraper blade elevation control method, device and system based on single GPS, can show reduce cost.
The utility model provides a complete technical scheme:
a single GPS land scraper high-speed control device comprises a GPS receiver, a first azimuth angle sensor, a second azimuth angle sensor, a third azimuth angle sensor and a lifting oil cylinder;
the GPS receiver is arranged at one end of a shovel blade of the land leveler and used for receiving the elevation signal of the current position;
the first azimuth angle sensor is arranged on a frame of the land leveler and used for detecting the rotation angle of the cutting blade around the transverse center line of the cutting blade of the land leveler;
the second azimuth angle sensor is arranged on the scraper knife and used for detecting the rotation angle of the scraper knife around the center line of the vertical horizontal plane;
the third azimuth angle sensor is arranged on a traction frame rotating disc of the land scraper and used for detecting the rotation angle of the scraper around the center line of the running direction of the land scraper;
two ends of the scraper knife are respectively provided with a lifting oil cylinder, and the lifting oil cylinders adjust the height of the scraper knife to a target value according to signals of the GPS receiver, the first azimuth angle sensor, the second azimuth angle sensor and the third azimuth angle sensor.
Further, the GPS receiver is disposed at one end of the grader blade via a sensor mount.
Further, the first azimuth angle sensor arrangement plane is parallel to the ground.
Further, the second azimuth sensor arrangement plane is parallel to the ground.
Further, the third azimuth angle sensor is movably connected to the traction frame rotating disc.
Furthermore, the lifting oil cylinder is controlled by a hydraulic multi-way valve to be adjusted.
Furthermore, rotation angle signals detected by the first azimuth angle sensor, the second azimuth angle sensor and the third azimuth angle sensor and a current position elevation signal received by the GPS receiver are all transmitted to the controller, and the controller drives the lifting oil cylinder to act through the hydraulic multi-way valve.
A method for controlling the elevation of a single GPS grader blade comprises the following steps:
defining a coordinate system: establishing a coordinate system by taking a horizontal plane as a reference plane and a projection of an intersection point of a transverse center line of a cutting blade of the land scraper and a longitudinal center line of the land scraper on the horizontal plane as an origin O, wherein the X-axis direction in the coordinate system is the transverse moving direction of the cutting blade, the Y-axis direction is the running direction of a land scraper vehicle, and the Z-axis direction is the upward direction vertical to the horizontal plane; after the coordinate vector of one end of the GPS receiver arranged on the land scraper blade is translated to the origin, the initial coordinate vector of the other end without the GPS receiver is defined as (X1, Y1, Z1);
detecting an elevation signal of one end of a cutting blade of the land scraper, and acquiring coordinates (X0, Y0 and Z0) of the cutting blade in a coordinate system, wherein a first azimuth angle sensor acquires a rotation angle α of the cutting blade around a transverse center line of the cutting blade of the land scraper, a second azimuth angle sensor 5 acquires a rotation angle β of the cutting blade around a center line of a vertical horizontal plane, and a third azimuth angle sensor acquires a rotation angle gamma of the cutting blade around a center line of the land scraper in a driving direction;
and dynamically calculating coordinate values (X2, Y2 and Z2) of the other end of the blade without the GPS receiver to obtain a target value Z2 of the elevation of the other end of the blade, and driving the left lifting cylinder and the right lifting cylinder to move through the hydraulic multi-way valve to adjust the elevation of the other end of the blade to the target value Z2.
Further, when the land scraper operates according to any one of the following working modes, the target value Z2 of the elevation adjustment at the other end of the cutting blade is calculated by a corresponding control equation;
the working mode 1: the grader blade only moves in the X direction, Z2= Z1+ Z0;
the working mode 2: the grader blade only moves in the Y direction, Z2= Z1+ Z0;
the working mode 3 is that the rotation of the cutting blade of the land scraper is equivalent to the rotation angle β of the cutting blade of the land scraper around the Z axis on the XOY plane, and Z2= Z1+ Z0;
the working mode 4 is that the land scraper moves along the driving direction with a certain pitch angle, which is equivalent to the rotation angle α of the land scraper blade around the X axis on the YOZ plane, and Z2= (Y1-Y0) sin (α) + (Z1-Z0) cos (α) + Z0;
the working mode 5 is that the land scraper moves along a certain transverse gradient along the running direction, which is equivalent to the rotation angle gamma of the land scraper around the Y axis on the XOZ plane, and Z2= (Z1-Z0) × (α) + (X1-X0) × (gamma) + Z0;
the operation mode 6 is that the land scraper has a certain pitch angle and a certain transverse gradient movement along the traveling direction, which is equivalent to that the land scraper rotates around an X axis at a rotation angle α on a YOZ plane and around a Y axis at a rotation angle gamma on an XOZ plane, and Z2= (Y1 '-Y0) × sin (α) + (Z1' -Z0) × cos (α) + Z0.
Further, when the land scraper operates in the mode formed by combining the working modes, corresponding control equations are sequentially superposed in a combined mode to solve the target value Z2 of the elevation adjustment.
The utility model discloses the beneficial effect who reaches:
to the current problem that two GPS control mode are with high costs of leveler, the utility model discloses only adopt single GPS receiver, combine the azimuth sensor to assist the detection, adopt the azimuth sensor still less to realize the elevation control of high accuracy, this system only adopts a GPS receiver, greatly reduced GPS system application cost.
Drawings
FIG. 1 is a land leveler elevation control system;
FIG. 2 is a translation vector conversion diagram;
FIG. 3 is a grader height control flow chart;
FIG. 4 is a GPS-only grader blade elevation system.
Detailed Description
The present invention will be further described with reference to the accompanying drawings. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.
Example 1
As shown in fig. 1 and 2, the utility model provides a single GPS land scraper knife height control device, including GPS receiver 2, sensor support 3, azimuth sensor 5, traction frame rotary disk 6, frame 7, azimuth sensor 8, perching knife 9, azimuth sensor 10, right lift cylinder 1 and left lift cylinder 4.
Performing coordinate system definition: establishing a coordinate system by taking a horizontal plane as a reference plane and a projection of an intersection point of a transverse center line of a cutting blade of the land scraper and a longitudinal center line of the land scraper on the horizontal plane as an origin O, wherein the X direction in the coordinate system is the transverse moving direction of the cutting blade, the Y direction is the driving direction of a land scraper vehicle, and the Z direction is the direction vertical to the horizontal plane and pointing to a GPS receiver; after the grader blade vector GPS end is translated to the origin, the initial no GPS end vector is defined as (X1, Y1, Z1).
The GPS receiver 2 is positioned on the sensor support 3, the sensor support 3 is positioned at the left end or the right end of the grader blade, and the sensor support 3 and the grader blade are fixed through bolts or welding; the GPS receiver 2 receives elevation signals of the current position.
The azimuth angle sensor 8 is located on the grader frame 7, the grader frame 7 is integrally and rigidly connected with the grader, the arrangement plane of the azimuth angle sensor 8 on the grader frame 7 is parallel to the ground, and the output signal of the azimuth angle sensor 8 is detected to be a first rotation angle α.
The azimuth angle sensor 5 is positioned on a rotary disc 6 of a traction frame of the grader, the rotary disc 6 of the traction frame is movably connected with the azimuth angle sensor 5, and the azimuth angle sensor 5 detects an output signal as a second rotation angle β of the grader cutting blade.
The azimuth angle sensor 10 is positioned on the grader blade 9, and the grader blade 9 is rigidly connected with the azimuth angle sensor 10; the arrangement plane of the azimuth angle sensor 10 above the grader blade 9 is parallel to the ground; the azimuth sensor 10 detects the output signal as the third rotation angle γ of the grader blade.
The first rotational angle α is the angle at which the grader blade is rotated about the X-axis, the second rotational angle β is the angle at which the grader blade is rotated about the Z-axis, and the third rotational angle γ is the angle at which the grader blade is rotated about the Y-axis.
And one end of the left lifting oil cylinder 4 is connected with the left end of the cutting blade of the land scraper in a hinged mode, and one end of the right lifting oil cylinder 1 is connected with the right end of the cutting blade of the land scraper in a hinged mode. And the lifting oil cylinder adjusts the elevation of the scraper knife to a target value according to signals of the GPS receiver 2, the azimuth sensor 8, the azimuth sensor 5 and the azimuth sensor 10.
Preferably, as shown in fig. 4, the GPS receiver 2, the azimuth sensor 8, the azimuth sensor 5, and the azimuth sensor 10 are connected to the controller via a communication cable or a communication protocol; the elevation of the other end of the land leveling scraper blade is calculated and converted through the controller, the action of the hydraulic multi-way valve is controlled, the displacement of the left lifting oil cylinder 4 and the right lifting oil cylinder 1 is further controlled, and the elevations of the two ends of the land leveling scraper blade are adjusted through the left lifting oil cylinder 4 and the right lifting oil cylinder 1.
The elevation calculating method of the single GPS grader blade comprises the following steps:
taking the example that the GPS receiver is disposed on the left side of the grader blade (when the GPS receiver is disposed on the right side of the grader blade, the same is true), the signal of the GPS receiver 2 on the left side is detected, the coordinate of the GPS receiver in the coordinate system is acquired (X0, Y0, Z0), the azimuth sensor 8 detects and acquires the first rotation angle α, the azimuth sensor 5 detects and acquires the second rotation angle β, the azimuth sensor 10 detects and acquires the third rotation angle γ, the coordinate values (X2, Y2, Z2) of the GPS-less end blade are dynamically calculated, and the Z2 value is the other-end elevation value.
As shown in FIG. 3, the control steps for the height of the land scraper are as follows:
1. establishing a reference coordinate system;
2. acquiring a GPS end coordinate of a land scraper;
3. translating the blade vector of the land leveler to the origin of coordinates;
4. calculating an initial coordinate without a GPS terminal;
3. calculating the height of the side shovel without the GPS according to the working posture of the land leveler;
6. comparing the design elevation with the actual elevation;
7. controlling the movement of the hydraulic cylinder.
The single GPS grader blade elevation calculation example is as follows:
the working mode 1: transverse movement of grader blade
When the cutting blade of the grader is moved laterally, the grader blade is moved only in the X direction, and the coordinate values (X2, Y2, Z2) of the GPS-less end blade at this time are given by the following governing equation:
Z2=Z1+Z0；X2=X1+X0；Y2=Y1+Y0。
the working mode 2: the grader moves in the direction of travel
When the grader is moving in the direction of travel, the grader blade only moves in the Y direction, and the coordinate values (X2, Y2, Z2) for the GPS-less end blade are given by the following governing equation:
Z2=Z1+Z0；X2=X1+X0；Y2=Y1+Y0。
working mode 3: rotary motion of the blade of a grader
During the rotary motion of the blade, the blade is equivalent to rotating around the Z axis in the XOY plane by a second rotation angle β detected by the azimuth sensor 5, and the coordinate values (X2, Y2, Z2) of the blade without the GPS end are given by the following control equation:
Z2=Z1+Z0；
X2=(X1-X0)*cos（β)-(Y1-Y0)*sin(β)+X0；
Y2=(X1-X0)*sin(β)+(Y1-Y0)*cos(β)+Y0。
working mode 4: the grader moves in the longitudinal direction (the direction of travel of the grader)
The grader is moving in the longitudinal direction (grader direction of travel), at which time the grader has a certain pitch angle, the grader blade is equivalent to rotating around the X-axis in the YOZ plane, and the rotation angle is the first rotation angle α detected by the azimuth sensor 8, at which time the coordinate values (X2, Y2, Z2) of the GPS-less end blade are given by the following control equation:
X2=X1+X0；
Y2=(Y1-Y0)*cos(α)-(Z1-Z0)*sin(α)+Y0；
Z2=(Y1-Y0)*sin(α)+(Z1-Z0)*cos(α)+Z0。
the working mode 5: the grader moves in the direction of travel (with a cross slope)
The land scraper moves along the driving direction (with a cross slope), the land scraper has a certain cross slope, the land scraper equivalently rotates around the Y axis on the XOZ plane, and the rotation angle is a third rotation angle gamma detected by the azimuth angle sensor 10; the coordinate values (X2, Y2, Z2) of the GPS-less end blade at this time are given by the following governing equation:
Y2=Y1+Y0；
X2=(Z1-Z0)*sin(γ)-(X1-X0)*cos(γ)+X0；
Z2=(Z1-Z0)*cos(α)+(X1-X0)*cos(γ)+Z0。
working mode 6, the land scraper moves on the road surface with a cross slope gamma and a longitudinal slope α
When the motor grader moves on a road surface having a cross slope (third rotation angle γ) and a longitudinal slope (first rotation angle α), the control equation is as follows:
calculating GPS-free end coordinates (X2 ', Y2 ', Z2 ') according to the distance with the cross slope (third rotation angle gamma)
X2’=(Z1)*sin(γ)-(X1)*cos(γ)；
Z2’=(Z1)*cos(α)+(X1)*cos(γ)；
Y2’=Y1；
On the basis of the above calculation, GPS-free end coordinates (X2, Y2, Z2) are calculated according to the longitudinal slope (first rotation angle α)
X2=X2’+X0；
Y2=(Y2’-Y0)*cos(α)-(Z2’-Z0)*sin(α)+Y0；
Z2=(Y2’-Y0)*sin(α)+(Z2’-Z0)*cos(α)+Z0。
Working mode 7: combined movement of land leveler
When the grader is combined with the multiple motion modes at the same time, the superposition calculation is carried out in sequence.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be considered as the protection scope of the present invention.
Claims (7)
1. A single GPS land scraper high-speed control device is characterized by comprising a GPS receiver, a first azimuth angle sensor, a second azimuth angle sensor, a third azimuth angle sensor and a lifting oil cylinder;
the GPS receiver is arranged at one end of a shovel blade of the land leveler and used for receiving the elevation signal of the current position;
the first azimuth angle sensor is arranged on a frame of the land leveler and used for detecting the rotation angle of the cutting blade around the transverse center line of the cutting blade of the land leveler;
the second azimuth angle sensor is arranged on the scraper knife and used for detecting the rotation angle of the scraper knife around the center line of the vertical horizontal plane;
the third azimuth angle sensor is arranged on a traction frame rotating disc of the land scraper and used for detecting the rotation angle of the scraper around the center line of the running direction of the land scraper;
two ends of the scraper knife are respectively provided with a lifting oil cylinder, and the lifting oil cylinders adjust the height of the scraper knife to a target value according to signals of the GPS receiver, the first azimuth angle sensor, the second azimuth angle sensor and the third azimuth angle sensor.
2. The single GPS grader blade height control apparatus of claim 1 wherein the GPS receiver is mounted on one of the ends of the grader blade by a sensor mount.
3. The single GPS land scraper height control apparatus of claim 1, wherein the first azimuth sensor arrangement plane is parallel to the ground.
4. The single GPS land scraper height control apparatus of claim 1, wherein the second azimuth sensor arrangement plane is parallel to the ground.
5. The single GPS grader blade height control apparatus of claim 1 wherein the third azimuth sensor is movably attached to the traction frame rotating disk.
6. The single GPS land level scraper height control device of claim 1, wherein the lift cylinder is regulated by hydraulic multi-way valve control.
7. The single GPS land leveller blade height control device as claimed in claim 6, wherein the rotation angle signals detected by the first azimuth sensor, the second azimuth sensor and the third azimuth sensor, and the current position height signal received by the GPS receiver are all transmitted to the controller, and the controller drives the lifting cylinder to act through the hydraulic multi-way valve.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110374154A (en) * | 2019-07-24 | 2019-10-25 | 江苏徐工工程机械研究院有限公司 | Single GPS land leveler blade height control device and control method |
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| CN110374154A (en) * | 2019-07-24 | 2019-10-25 | 江苏徐工工程机械研究院有限公司 | Single GPS land leveler blade height control device and control method |
| CN110374154B (en) * | 2019-07-24 | 2024-03-01 | 江苏徐工工程机械研究院有限公司 | Single GPS land leveler shovel blade elevation control device and control method |
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