A leveling method of a rotary lifting leveling platform

Abstract

The application provides a leveling method of a rotary lifting leveling platform, and the rotary lifting leveling platform mainly comprises a deflection working mechanism, a rotary lifting mechanism, a posture sensor, a Hall angle sensor and a distance sensor; the horizontal inclination angles X and Y of the platform in the transverse direction and the longitudinal direction are obtained through the posture sensor, the positive and negative values thereof satisfy the right-hand screw rule, the obtained data is subjected to Kalman filtering, and then the filtered data, the data obtained by the Hall angle sensor and the data obtained by the distance sensor are used to control the movement of the rotary lifting leveling platform, so that the inapplicability of the traditional position error control leveling method and the angle error leveling method in the rotary lifting leveling platform is overcome, and the rotary lifting leveling platform has the advantages of short response time, strong anti-interference capability and high reliability.

Description

Technical Field

[0001] This invention relates to the technical field of automatic position and posture adjustment of agricultural machinery platforms, and more specifically, to a leveling method for a rotary lifting leveling platform. Background Technology

[0002] my country is a major agricultural country, and the level of agricultural mechanization affects the modernization level of its agriculture. Traditional manual leveling operations cannot keep up with the rapid development of agricultural machinery automation and intelligence. Automatic leveling technology for agricultural machinery effectively solves the problems of poor quality and low efficiency in complex operating environments such as uneven plots, complex terrain, and tilting. It has been applied in various agricultural mechanization operation scenarios, including mountainous areas, orchards, paddy fields, and cultivated land. With the rapid development of intelligent agricultural machinery, automatic leveling technology has been gradually applied to all aspects of the agricultural machinery field. Automatic leveling technology for mountain agricultural machinery has become an inevitable requirement for the current agricultural mechanization and automation. The installation of intelligent technologies such as automatic leveling and real-time monitoring significantly improves the accuracy and unmanned nature of agricultural mechanized production. Automatic leveling technology for agricultural machinery has become an important research area for the future development of intelligent agricultural machinery. It is foreseeable that the development space for automatic leveling technology for agricultural machinery is vast. Automatic leveling devices are used to adjust the real-time posture of the work platform so that the work platform carrying the work tools is kept in a horizontal position. At present, the most commonly used leveling methods for multi-point platforms are position error control leveling method and angle error leveling method. However, both of these methods directly control the extension and retraction of the outriggers to make the platform horizontal, without including the control of rotational motion. Therefore, they are not suitable for rotary lifting leveling platforms. Summary of the Invention

[0003] This invention proposes a leveling method for a rotary lifting leveling platform to solve the problems mentioned in the background art. It features clear logic, fast response speed, and high adjustment accuracy.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A rotary lifting leveling platform includes a deflection mechanism, a rotary lifting mechanism, an attitude sensor, a Hall angle sensor, and a distance sensor. The deflection mechanism includes a chassis fixed platform, a ball joint, a ball joint fine-tuning base, a telescopic mechanism, and a tool mounting platform. The tool mounting platform is connected to the chassis fixed platform via the ball joint, the ball joint fine-tuning base, and the telescopic mechanism. The rotary lifting mechanism includes a lower rotary lifting platform, a central rotating rod, an electric push rod, a slip ring, a diamond-shaped lifting mechanism, an upper rotary lifting platform, and a transmission link. The upper rotary lifting platform is connected to the lower rotary lifting platform via the central rotating rod, the electric push rod, the diamond-shaped lifting mechanism, and the transmission link. The deflection mechanism is connected to the rotary lifting mechanism via toothed bearings and toothless bearings. A stepper motor is installed at the bottom of the chassis fixed platform. The speed output of the stepper motor is reduced by a reducer and then output to a pinion. The platform reaches a horizontal position due to the lifting motion of the electric push rod and the rotational motion of the rotary lifting mechanism driven by the stepper motor through the toothed bearings.

[0006] The diamond-shaped lifting mechanism can amplify the movement speed of the electric push rod; there are two electric push rods and two central rotating rods, one end of which is evenly and alternately fixed on the upper rotating lifting platform, and the other end of the central rotating rod is hinged to the lower rotating lifting platform. The other end of the electric push rod is connected to the diamond-shaped lifting mechanism through a transmission link.

[0007] As a preferred embodiment of the present invention, a distance sensor is installed on the outer side of one of the electric push rods to detect the distance the electric push rod extends in real time; a Hall angle sensor is installed at the center of the slip ring to detect the angle rotated by the rotary lifting mechanism in real time; and an attitude sensor is installed on the work tool mounting platform to detect the position and attitude of the work tool mounting platform in real time.

[0008] A leveling method based on the above-mentioned rotary lifting leveling platform has the following contents:

[0009] The attitude sensor acquires the horizontal tilt angles X and Y of the installation platform of the work tool, which satisfy the right-hand screw rule. The obtained X and Y values ​​are then subjected to Kalman filtering, and the movement of the stepper motor and electric actuator is controlled by the filtered data.

[0010] Set the threshold values ​​for |X| and |Y| to α. When both |X| and |Y| are less than α, neither the stepper motor nor the electric actuator moves. When either |X| or |Y| is greater than α, data from the distance sensor and the Hall angle sensor are acquired. The deflection angle γ of the work tool mounting platform around the hinge point of the central rotating rod relative to the horizontal plane is calculated using the movement distance d of the electric actuator obtained from the distance sensor. The rotation angle θ is obtained using the Hall angle sensor. Then, based on the values ​​of γ and θ, the angles X1 and Y1 that the leveling mechanism has deflected at this point are calculated.

[0011]

[0012] Add this to the corresponding X and Y coordinates; the obtained actual tilt angle required by the installation platform for the work equipment corresponding to the current road surface satisfies...

[0013]

[0014] Calculate the corresponding actual rotation angle θ' and actual deflection angle γ' required based on the actual tilt angle needed for the installation platform.

[0015]

[0016] Then, based on the actual deflection angle γ' required by the deflection, the corresponding actual distance d' of the electric push rod lifting and lowering is calculated. The movement of the stepper motor and the electric push rod is controlled by subtracting the actual rotation angle θ' and the actual distance d' obtained by the corresponding sensor from the calculated actual rotation angle θ and the actual distance d'.

[0017] As a preferred technical solution of the present invention, the rotation angle θ of the rotary lifting mechanism is controlled between -90° and 90°. According to the right-hand screw rule satisfied by the attitude sensor, when Y'>0, the value of θ'-180° should be assigned to θ', and the value of -γ' should be assigned to γ'.

[0018] As a preferred embodiment of the present invention, the range of motion of the electric actuator is (-d0, d0). The possible situations of the actual distance d' are explained below. When the range of the calculated d' is between (-d0, d0), the actual distance d' that the electric actuator needs to raise or lower is directly output. If the range of the calculated actual distance d' is between (d0, +∞), it exceeds the upper boundary value of the electric actuator's range of motion, and d' is assigned the value d0. If the range of the calculated actual distance d' is between (-∞, -d0), it exceeds the lower boundary value of the electric actuator's range of motion, and d' is assigned the value -d0. After determining the value of d, the actual distance d' is subtracted from the d obtained by the distance sensor to obtain Δd. When the value of Δd is less than a certain threshold, Δd is assigned the value of 0, and the movement time t of the electric actuator is 0. When |Δd| is greater than or equal to the threshold, the movement time t of the electric actuator can be determined based on the speed of the electric actuator. The time t, as a coordination parameter of lifting and rotating motion, will participate in controlling the movement of the stepper motor.

[0019] As a preferred embodiment of the present invention, the actual rotation angle θ' or the actual rotation angle θ'' minus the θ obtained by the Hall angle sensor is used to obtain Δθ. The threshold of Δθ is set as θ0. The movement of the stepper motor and the electric actuator is as follows: when t = 0, Δθ ≥ θ0, the electric actuator does not move, and the stepper motor moves forward at its maximum speed; when t = 0, Δθ ≤ -θ0, the electric actuator does not move, and the stepper motor moves in the reverse direction at its maximum speed; when t ≠ 0, |Δθ| < θ0, t > 0, the electric actuator moves forward, t < 0, the electric actuator moves in the reverse direction, and the stepper motor does not move; when t ≠ 0, |Δθ| ≥ θ0, the speed ω of the stepper motor is Δθ / |t|; ω > 0, the stepper motor rotates forward, ω < 0, the stepper motor rotates in reverse, and the speed of the stepper motor cannot exceed its maximum speed.

[0020] The beneficial effects of this invention are as follows: The leveling method for the rotary lifting leveling platform proposed in this invention uses a distance sensor, a Hall angle sensor, and an attitude sensor to jointly control the movement of the stepper motor and the electric push rod. This overcomes the inapplicability of traditional position error control leveling methods and angle error leveling methods in rotary lifting leveling platforms. It has the advantages of short response time, strong anti-interference ability, and high reliability. Furthermore, it provides an important conversion algorithm that coordinates the movement of the electric push rod with the movement of the stepper motor by controlling the movement time of the electric push rod, ensuring that there is no larger deflection in other directions during the leveling process. The two electric push rods in this invention always move at the same speed and opposite directions, eliminating the need for a distance sensor for each motor, thus reducing complexity. At the same time, this leveling algorithm can be applied to real-time control, reducing the risk of rollover of the vehicle body, including the leveling platform. Based on the above algorithm, the provided leveling method for the rotary lifting leveling platform has the advantages of clear control logic, fast response speed, and high adjustment accuracy. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the rotating lifting leveling platform and sensor installation of the present invention.

[0022] Figure 2 This is a schematic diagram of the deflection mechanism of the present invention;

[0023] Figure 3 This is a schematic diagram of the rotary lifting mechanism of the present invention;

[0024] Figure 4 This is a schematic diagram of the right-hand screw rule for an attitude sensor.

[0025] Figure 5 Control flowchart for the leveling method

[0026] Attached image caption:

[0027] 1. Stepper motor; 2. Reducer; 3. Chassis mounting platform; 4. Pinion gear; 5. Ball joint; 6. Telescopic mechanism; 7. Tool mounting platform; 8. Rotating and lifting upper platform; 9. Rotating and lifting lower platform; 10. Gearless bearing; 11. Geared bearing; 12. Ball joint fine-tuning base; 13. Central rotating rod; 14. Diamond-shaped lifting mechanism; 15. Transmission link; 16. Slip ring; 17. Electric push rod; 201. Attitude sensor; 202. Distance sensor; 203. Hall angle sensor. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and should not be construed as limiting the specific scope of protection of this invention.

[0029] Please see Figures 1-5 This invention provides a leveling method for a rotary lifting leveling platform. The rotary lifting leveling platform includes a deflection working mechanism, a rotary lifting mechanism, an attitude sensor 201, a Hall angle sensor 203, and a distance sensor 202. The deflection working mechanism includes a chassis fixing platform 3, a ball joint 5, a ball joint fine-tuning base 12, a telescopic mechanism 6, and a tool mounting platform 7. The tool mounting platform 7 is connected to the chassis fixing platform 3 via the ball joint 5, the ball joint fine-tuning base 12, and the telescopic mechanism 6. The rotary lifting mechanism includes a rotary lifting lower platform 9, a central rotating rod 13, an electric push rod 17, and a slip ring 16. The system comprises a diamond-shaped lifting mechanism 14, a rotating lifting upper platform 8, and a transmission link 15. The rotating lifting upper platform 8 is connected to the rotating lifting lower platform 9 via a central rotating rod 13, an electric push rod 17, the diamond-shaped lifting mechanism 14, and the transmission link 15. The deflection mechanism is connected to the rotating lifting mechanism via a toothed bearing 11 and a toothless bearing 10. A stepper motor 1 is installed at the bottom of the chassis fixed platform 3. The speed output by the stepper motor 1 is reduced by a reducer 2 and then output to a pinion 3. The platform reaches a horizontal position due to the lifting motion of the electric push rod 17 and the rotational motion of the rotating lifting mechanism driven by the stepper motor 1 through the toothed bearing 11.

[0030] The diamond-shaped lifting mechanism 14 can amplify the movement speed of the electric push rod 17; there are two electric push rods 17 and two central rotating rods 13. One end of the electric push rod 17 and the central rotating rod 13 are evenly and alternately fixed on the rotating lifting upper platform 8, and the other end of the central rotating rod 13 is hinged to the rotating lifting lower platform 9. The other end of the electric push rod 17 is connected to the diamond-shaped lifting mechanism 14 through the transmission link 15.

[0031] As a preferred embodiment of the present invention, a distance sensor 202 is installed on the outer side of one of the electric push rods 17 to detect the distance the electric push rod 17 extends in real time; a Hall angle sensor 203 is installed at the center of the slip ring 16 to detect the angle rotated by the rotary lifting mechanism in real time; and an attitude sensor 201 is installed on the work tool mounting platform 7 to detect the position and attitude of the work tool mounting platform 7 in real time.

[0032] A leveling method based on the above-mentioned rotary lifting leveling platform has the following contents:

[0033] The attitude sensor 201 acquires the horizontal and longitudinal tilt angles X and Y of the work tool installation platform 7, performs Kalman filtering on the acquired data, and then controls the movement of the stepper motor 1 and the electric push rod 17 using the filtered data.

[0034] Let the threshold values ​​for |X| and |Y| be α. When both |X| and |Y| are less than α, neither the stepper motor 1 nor the electric push rod 17 moves. When either |X| or |Y| is greater than α, data from the distance sensor 202 and the Hall angle sensor 203 are acquired. The deflection angle γ of the work tool mounting platform 7 around the hinge of the central rotating rod 13 relative to the horizontal plane is calculated using the movement distance d of the electric push rod 17 acquired by the distance sensor 202. The rotation angle θ is acquired using the Hall angle sensor 203. Then, based on the values ​​of γ and θ, the angles X1 and Y1 that the leveling mechanism has deflected at this time are calculated.

[0035]

[0036] And add it to the corresponding X and Y; the obtained actual tilt angle required by the current road surface for the installation platform 7 of the working equipment meets the requirements.

[0037]

[0038] Based on the actual tilt angle required by the installation platform 7, calculate the corresponding actual rotation angle θ' and actual deflection angle γ'.

[0039]

[0040] Then, the actual distance d' of the electric push rod 17 being raised and lowered is calculated according to the actual deflection angle γ' required by the required deflection angle. The movement of the stepper motor 1 and the electric push rod 17 is controlled by subtracting the actual rotation angle θ' and the actual distance d' obtained by the corresponding sensor from the actual rotation angle θ and the distance d.

[0041] As a preferred technical solution of the present invention, the rotation angle of the rotary lifting mechanism is controlled between -90° and 90°. According to the right-hand screw rule satisfied by the attitude sensor 201, when Y'>0, the value of θ'-180° should be assigned to θ', and the value of -γ' should be assigned to γ'.

[0042] As a preferred embodiment of the present invention, the range of motion of the electric actuator 17 is (-d0, d0). The possible situations of the actual distance d' are explained below. When the range of the calculated d' is between (-d0, d0), the actual distance d' that the electric actuator 17 needs to move up and down is directly output. If the range of the calculated actual distance d' is between (d0, +∞), it exceeds the upper boundary value of the displacement range of the electric actuator 17, and d' is assigned the value d0. If the range of the calculated actual distance d' is between (-∞, -d0), it exceeds the lower boundary value of the displacement range of the electric actuator 17, and d' is assigned the value -d0. After determining the value of d, the actual distance d' is subtracted from the d obtained by the distance sensor 202 to obtain Δd. When the value of Δd is less than a certain threshold, Δd is assigned the value of 0, and the movement time t of the electric push rod 17 is 0. When |Δd| is greater than or equal to the threshold, the movement time t of the electric push rod 17 can be determined based on the speed of the electric push rod 17. The time t, as a coordination parameter of lifting and rotating motion, will participate in controlling the movement of the stepper motor 1.

[0043] As a preferred embodiment of the present invention, the actual rotation angle θ' is subtracted from the θ obtained by the Hall angle sensor 203 to obtain Δθ. Let the threshold of Δθ be θ0. The movement of the stepper motor 1 and the electric push rod 17 is as follows: When t = 0 and Δθ ≥ θ0, the electric push rod 17 does not move, and the stepper motor 1 moves forward at its highest speed; when t = 0 and Δθ ≤ -θ0, the electric push rod 17 does not move, and the stepper motor 1 moves in the reverse direction at its highest speed; when t ≠ 0 and |Δθ| < θ0, t > 0, the electric push rod 17 moves forward, t < 0, the electric push rod moves in the reverse direction, and the stepper motor 1 does not move; when t ≠ 0 and |Δθ| ≥ θ0, the rotational speed of the stepper motor 1 is... w For Δθ / |t|; ω>0, the stepper motor rotates forward; ω<0, the stepper motor rotates in reverse; the speed of the stepper motor cannot exceed its maximum speed.

[0044] The working principle of this invention is as follows: When the leveling mechanism is working, the movement mode is divided into two modes: lifting movement and rotational movement. When encountering an inclined road surface, the machine body tilts. At this time, the data obtained by the attitude sensor 201 is compared with the set threshold after being filtered by Kalman. If it is less than the set threshold, the stepper motor 1 and the electric push rod 17 do not move. If it is greater than or equal to the set threshold, the Hall angle sensor 203 obtains the angle that the rotating lifting mechanism has rotated at the current moment; the distance sensor 202 obtains the distance that the electric push rod 17 has moved at the current moment. Then, the data obtained by the Hall angle sensor 203 and the distance sensor 202 are converted into the tilt angle that the working tool installation platform 7 has deflected at the current moment through an algorithm. Then, it is processed with the tilt angle obtained by the attitude sensor 201 to calculate the angle that the rotating lifting mechanism needs to rotate to and the distance that the electric push rod 17 needs to move to. Then, it is calculated with the values ​​at the current moment to obtain the movement direction and movement amount of the electric push rod 17 and the stepper motor 1, so that the working tool installation platform 7 reaches the horizontal position.

[0045] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A leveling method of a rotary lift leveling platform, the leveling method employing a rotary lift leveling platform, characterized by, The rotary lifting leveling platform includes a deflection working mechanism, a rotary lifting mechanism, an attitude sensor (201), a Hall angle sensor (203), and a distance sensor (202); the deflection working mechanism includes a chassis fixed platform (3), a ball hinge (5), a ball hinge fine-tuning base (12), a telescopic mechanism (6), and a work tool mounting platform (7); the work tool mounting platform (7) is connected to the chassis fixed platform (3) through the ball hinge (5), the ball hinge fine-tuning base (12), and the telescopic mechanism (6); the rotary lifting mechanism includes a rotary lifting lower platform (9), a central rotating rod (13), an electric push rod (17), a slip ring (16), a diamond lifting mechanism (14), and a rotary lifting... The upper platform (8) and transmission link (15) are lowered; the upper rotating platform (8) is connected to the lower rotating platform (9) through the central rotating rod (13), electric push rod (17), diamond lifting mechanism (14), and transmission link (15); the deflection working mechanism is connected to the rotating lifting mechanism through toothed bearing (11) and toothless bearing (10); a stepper motor (1) is installed at the bottom of the chassis fixed platform (3), and the speed output by the stepper motor (1) is reduced by the reducer (2) and output to the pinion (4); the platform reaches a horizontal position due to the lifting movement of the electric push rod (17) and the rotational movement of the rotating lifting mechanism driven by the stepper motor (1) through the toothed bearing (11); A distance sensor (202) is installed on one of the outer sides of the electric push rod (17) to detect the distance the electric push rod (17) extends in real time. A Hall angle sensor (203) is installed at the center of the slip ring (16) to detect the angle rotated by the rotary lifting mechanism in real time. An attitude sensor (201) is installed on the tool installation platform (7) to detect the position and posture of the tool installation platform (7) in real time; The leveling method includes the following: The attitude sensor (201) acquires the horizontal tilt angles X and Y of the work tool installation platform (7) in the lateral and longitudinal directions, performs Kalman filtering on the acquired data, and then controls the movement of the stepper motor (1) and electric push rod (17) through the filtered data; The threshold values ​​for |X| and |Y| are set to α. When both |X| and |Y| are less than α, neither the stepper motor (1) nor the electric push rod (17) moves. When either |X| or |Y| is greater than α, data from the distance sensor (202) and the Hall angle sensor (203) are obtained. The deflection angle γ of the work tool installation platform (7) around the hinge of the central rotating rod (13) and the horizontal plane is calculated using the movement distance d of the electric push rod (17) obtained by the distance sensor (202). The rotation angle θ is obtained by the Hall angle sensor (203). Then, based on the values ​​of γ and θ, the angles X1 and Y1 that the leveling mechanism has deflected at this time are calculated. And add it to the corresponding X and Y; the actual tilt angle required by the current road surface corresponding to the tool installation platform (7) meets the requirements. Based on the actual tilt angle required by the installation platform (7), calculate the corresponding actual rotation angle θ' and actual deflection angle γ', and Then, the actual distance d' of the electric push rod (17) to rise and fall is calculated according to the actual deflection angle γ' required by the actual deflection. The movement of the stepper motor (1) and the electric push rod (17) is controlled by subtracting the actual rotation angle θ' and the actual distance d' obtained by the corresponding sensor from the obtained actual rotation angle θ and distance d. The rotation angle of the rotary lifting mechanism is controlled between -90° and 90°. According to the right-hand screw rule satisfied by the attitude sensor (201), when Y'>0, the value of θ'-180° should be assigned to θ' and the value of -γ' should be assigned to γ'.

2. The method of claim 1, wherein, The range that the electric push rod (17) can move is (-d0, d0). When the range of the obtained d' is between (-d0, d0), the actual distance d' that the electric push rod (17) needs to lift is directly output. If the range of the obtained actual distance d' is between (d0, +∞), it exceeds the upper boundary value of the range of the electric push rod (17), and d' is assigned the value d0. If the range of the obtained actual distance d' is between (-∞, -d0), it exceeds the lower boundary value of the range of the electric push rod (17), and d' is assigned the value -d0. After completing the value of d, the obtained actual distance d' is subtracted from the d obtained by the distance sensor (202) to obtain Δd. When the value of Δd is less than a certain threshold, Δd is assigned the value 0, and the movement time t of the electric push rod (17) is 0. When |Δd When the speed of the electric push rod (17) is greater than or equal to the threshold, the time t of the electric push rod (17) is calculated based on the speed of the electric push rod (17). The time t is used as a coordination parameter of the lifting and rotating motion and will participate in the control of the stepper motor (1) motion.

3. The method of claim 1, wherein, The actual rotation angle θ' obtained is subtracted from the θ obtained by the Hall angle sensor (203) to obtain Δθ. The threshold of Δθ is set as θ0. The movement of the stepper motor (1) and the electric push rod (17) is as follows: When t=0, Δθ≥θ0, the electric push rod (17) does not move and the stepper motor (1) moves forward at the highest speed; when t=0, Δθ≤-θ0, the electric push rod (17) does not move and the stepper motor (1) moves backward at the highest speed; when t≠0, |Δθ|<θ0, t>0, the electric push rod (17) moves forward, t<0, the electric push rod moves backward and the stepper motor (1) does not move; when t≠0, |Δθ|≥θ0, the speed ω of the stepper motor (1) is Δθ / |t|; ω>0, the stepper motor rotates forward, ω<0, the stepper motor rotates backward, and the speed of the stepper motor cannot exceed its highest speed.

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