AGV forklift attachment control method and system

Abstract

The invention relates to an AGV forklift attachment control method which comprises an attachment inclination action control step, and the inclination action control step comprises the steps that an oil pump motor is controlled to drive an attachment to incline forwards or backwards, the current inclination angle of the attachment is obtained in real time, and the angle deviation value between the current inclination angle and the target inclination angle is obtained; the rotating speed of an oil pump motor of the AGV forklift is adjusted according to the current inclination direction and the angle deviation value; when the angle deviation value reaches a preset difference value I, the rotating speed of an oil pump motor is controlled to be reduced; when the angle deviation value reaches a second preset difference value, the oil pump motor is controlled to stop; wherein the second preset difference value is smaller than the first preset difference value. The system is reliable and clear in logic, is successfully applied to the AGV forklift, completes function and logic tests, is high in safety protection coefficient, is very low in use cost, and can achieve an intelligent safety protection function.

Description

Technical Field

[0001] The present invention relates to the technical field of AGV forklifts, and particularly to a control method and system for AGV forklift attachments. Background Art

[0002] An AGV forklift (Automated Guided Vehicle Forklift) is an unmanned intelligent equipment for material handling based on automatic navigation technology, which is widely used in manufacturing, warehousing logistics, medicine, e-commerce and other fields. Its core features are autonomous navigation, precise positioning and intelligent scheduling. It can replace traditional manual forklifts, greatly improving the operation efficiency and reducing the operation cost.

[0003] However, almost all of the existing AGV forklifts are only equipped with forks, and at most, forks with a side shifter are installed. Therefore, the existing AGV forklifts only simply control the lifting height and forward / backward tilting actions of the forks on the mast, and cannot perform closed-loop control on complex attachments. Moreover, there is no complete vehicle system for installing a rotary flat clamp attachment on an AGV forklift for systematic work. Therefore, there is a blank in the control logic of the rotary flat clamp attachment during the operation of the whole vehicle. An AGV forklift is a systematic solution design, and each action requires confirmation of relevant sensor signals to execute the next step. When handling and placing goods, it is necessary to detect whether the goods are in place, whether the attachment is clamped, whether the attachment is tilted forward / backward in place, whether the attachment is rotated in place, whether the attachment has been released in place, whether it is extended in place, etc. All these require relevant sensors for detection to proceed to the next step. Therefore, the installation of sensors and the accuracy of logical judgment are crucial. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide a control method and system for AGV forklift attachments, laying a good foundation for the systematic working logic of complex attachments of AGVs.

[0005] To achieve the above object, the present invention adopts the following technical solutions: The present invention first provides a control method for AGV forklift attachments, which includes a tilting action control step for the attachment. The tilting action control step includes: S11. Control the oil pump motor to drive the attachment to tilt forward or backward, and real-time obtain the current tilting angle of the attachment, and obtain the angle deviation value between the current tilting angle and the target tilting angle; S12. Adjust the rotation speed of the oil pump motor of the AGV forklift according to the current tilting direction and the angle deviation value; S13. When the angle deviation value reaches a preset difference value one, control the rotation speed of the oil pump motor to decrease; S14. When the angle deviation value reaches the preset difference two, control the oil pump motor to stop; wherein, the preset difference two is less than the preset difference one; S15. Control the entire tilting action to be completed within a predetermined time, otherwise remind of a fault after the predetermined time.

[0006] As a further improvement of the above solution of the present invention, the AGV forklift attachment control method further includes a control step for the attachment's action of clamping goods when there is goods, and the control step for the attachment's action of clamping goods when there is goods includes: S21. Detect the goods signal between the two clamping arms of the attachment; if there is a goods signal between the two clamping arms of the attachment, control the oil pump motor to drive the attachment to perform a clamping action so that the two clamping arms of the attachment approach each other; S22. Obtain the current pressure value received by the two clamping arms of the attachment, and obtain the pressure deviation value between the current pressure value and the target pressure value; S23. Obtain the distance between the two clamping arms of the attachment and the center position of the attachment and calculate the current distance between the two clamping arms of the attachment based on this, and compare the current distance with the target distance one A; wherein, the target distance one A = goods width + A1, 20 cm ≤ A1 ≤ 30 cm; S24. When the pressure deviation value reaches the preset difference three, and the current distance is less than the target distance one A, and the distances between the two clamping arms of the attachment and the center position of the attachment are both less than 1 / 2 A, then control the oil pump motor to stop; S25. Control the entire action of clamping goods when there is goods to be completed within a predetermined time, otherwise remind of a fault after the predetermined time.

[0007] As a further improvement of the above solution of the present invention, the AGV forklift attachment control method further includes a control step for the attachment's action of loosening the clamp when there is goods, and the control step for the attachment's action of loosening the clamp when there is goods includes: S31. Control the oil pump motor to drive the attachment to perform a loosening clamp action so that the two clamping arms of the attachment move away from each other; S32. Real-time detect the goods signal between the two clamping arms of the attachment, obtain the distance between the two clamping arms of the attachment and the center position of the attachment and calculate the current distance between the two clamping arms of the attachment based on this, and compare the current distance with the target distance one A; wherein, the target distance one A = goods width + A1, 20 cm ≤ A1 ≤ 30 cm; S32. If the goods signal between the two clamping arms of the attachment disappears, and the current distance between the two clamping arms of the attachment is greater than the target distance one A, and the distances between the two clamping arms of the attachment and the center position of the attachment are both greater than 1 / 2 A, control the oil pump motor to stop; S33. Control the entire action of loosening the clamp when there is goods to be completed within a predetermined time, otherwise remind of a fault after the predetermined time.

[0008] As a further improvement of the above solution of the present invention, the AGV forklift attachment control method further includes a control step for the no-load clamping action of the attachment, and the control step for the no-load clamping action includes: S41. Control the oil pump motor to drive the attachment to perform a clamping action so that the two clamping arms of the attachment approach each other; S42. Obtain the current pressure value received by the two clamping arms of the attachment, and compare the current pressure value with the target pressure value; S43. Obtain the distance between the two clamping arms of the attachment and the center position of the attachment, and calculate the current distance between the two clamping arms of the attachment based on this, and compare the current distance with the target distance two; wherein, the target distance two is the minimum distance between the clamping arms of the attachment in the closed state; S44. When the current pressure value is greater than the target pressure value and the current distance is equal to the target distance two, control the oil pump motor to stop; S45. The entire no-load clamping action control is completed within a predetermined time, otherwise a fault is reminded after the predetermined time.

[0009] As a further improvement of the above solution of the present invention, the AGV forklift attachment control method further includes a control step for the no-load unclamping action of the attachment, and the control step for the no-load unclamping action includes: S51. Control the oil pump motor to drive the attachment to perform an unclamping action so that the two clamping arms of the attachment move away from each other; S52. Real-time obtain the distance between the two clamping arms of the attachment and the center position of the attachment, and calculate the current distance between the two clamping arms of the attachment based on this, and compare the current distance with the target distance three; wherein, the target distance three is the maximum distance between the clamping arms of the attachment in the open state; S52. When the current distance between the two clamping arms of the attachment is equal to the target distance three, control the oil pump motor to stop; S53. The entire tilting action control is completed within a predetermined time, otherwise a fault is reminded after the predetermined time.

[0010] As a further improvement of the above solution of the present invention, the AGV forklift attachment control method further includes a control step for the load-carrying rotation action of the attachment, and the control step for the load-carrying rotation action includes: S61. Obtain the current pressure value received by the two clamping arms of the attachment, and compare the current pressure value with the target pressure value; when the current pressure value is greater than the target pressure value, control the oil pump motor to drive the attachment to rotate left or right; S62. Real-time obtain the current rotation angle of the attachment, and obtain the rotation angle deviation value between the current rotation angle and the target rotation angle; S63. When the rotation angle deviation value reaches the preset difference four, control the oil pump motor to stop; The entire load-carrying rotation action is controlled to be completed within a predetermined time; otherwise, a fault is alerted after the predetermined time.

[0011] As a further improvement to the above solution of the present invention, the AGV forklift attachment control method further includes an unloaded rotation action control step for the attachment, and the unloaded rotation action control step includes: S71. Control the oil pump motor to drive the attachment to rotate left or right; S72. Obtain the current rotation angle of the attachment in real time, and obtain the rotation angle deviation value between the current rotation angle and the target rotation angle; S73. When the rotation angle deviation value reaches a preset difference four, control the oil pump motor to stop; S74. The entire unloaded rotation action is controlled to be completed within a predetermined time; otherwise, a fault is alerted after the predetermined time.

[0012] The present invention also provides an AGV forklift attachment control system, which adopts the AGV forklift attachment control method as described above, and includes: A vehicle controller, which is used to control the operation of the oil pump motor and adjust the rotation speed of the oil pump motor; and An inclination sensor, which is used to detect the inclination angle of the attachment.

[0013] As a further improvement to the above solution of the present invention, the AGV forklift attachment control system further includes: A proximity switch, which is used to detect the cargo signal between the two clamping arms of the attachment; A pressure sensor, which is used to detect the pressure value received by the two clamping arms of the attachment; A distance sensor, which is used to detect the distance between the two clamping arms of the attachment; and An angle sensor, which is used to detect the rotation angle of the attachment.

[0014] The present invention also provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the steps of the AGV forklift attachment control method as described above are implemented.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention provides an AGV forklift attachment control method, including the functions of attachment inclination, clamping arm loosening and clamping, and left and right rotation of the clamping arms, which almost covers all the functional logics of the attachment, laying a good foundation for the systematic control of complex attachments of AGV forklifts. The logic of the present invention is reliable and clear, has been successfully applied to AGV forklifts, completed function and logic tests, has a high safety protection coefficient, a very low use cost, and can achieve an intelligent safety protection function.

[0016] 2. In the attachment tilting motion control step of the present invention, when the attachment approaches the horizontal or the rear tilting in-place position, the oil pump motor is controlled to decelerate, which can prevent the impact of goods and avoid damage.

[0017] 3. In the goods picking and clamping step of the present invention, a suitable range of clamping distances is preset to facilitate the handling of goods. This is because if the distance between the left and right clamping arms meets the requirements, but the opening distance between the two clamping arms deviates too much from the center position, there is a risk of pushing the goods; if a too large deviation is set, a too large reserved distance between the goods and in the middle of the goods is required, wasting warehouse space. The design of the present invention completely solves the risk of pushing the goods and the problem of space waste caused by the over-large opening of the clamping arms, and improves the working efficiency of the system.

[0018] 4. The present invention controls each action to be completed within a predetermined time and sets a fault prompt function. When the relevant action is not completed within the predetermined time, the whole vehicle will issue a fault prompt to avoid the vehicle waiting for a long time without being noticed, effectively solving the fault problem during the operation of the whole vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is the electrical schematic diagram of an AGV forklift attachment control system proposed by an embodiment of the present invention; Figure 2 is the structural schematic diagram of the rotary flat clamping attachment mentioned in the present invention; Figure 3 is the logic block diagram of an AGV forklift attachment control method proposed by an embodiment of the present invention.

[0020] Reference numerals: 1, vehicle controller one; 2, vehicle controller two; 3, driver; 4, oil pump motor; 5, inclination sensor; 6, proximity switch; 7, pressure sensor; 8, angle sensor; 9, DCDC module; 10, forward tilt solenoid valve; 11, rear tilt solenoid valve; 12, distance adjustment solenoid valve one; 13, left rotation solenoid valve; 14, right rotation solenoid valve; 15, left laser range finder; 16, right laser range finder; 17, lithium battery module; 18, fault indicator light; 19, distance adjustment solenoid valve two. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present invention more thorough and comprehensive.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this invention belongs. The terms used in the specification of this invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0023] Referring to Figure 1 , in this embodiment, a control system for an AGV forklift attachment is first proposed, which includes a vehicle controller, an inclination sensor 5, a proximity switch 6, a pressure sensor 7, a rangefinder, and an angle sensor 8. Among them, the rangefinder includes a left laser rangefinder 15 and a right laser rangefinder 16. In this embodiment, two vehicle controllers are provided, denoted as vehicle controller one 1 and vehicle controller two 2 respectively. The AGV forklift includes a DCDC module 9, a lithium battery module 17, a driver 3, an oil pump motor 4, a forward tilt solenoid valve 10, a rear tilt solenoid valve 11, a distance adjustment solenoid valve one 12, a distance adjustment solenoid valve two 19, a left rotation solenoid valve 13, and a right rotation solenoid valve 14.

[0024] The input end of the DCDC module 9 is connected to the lithium battery module 17 of the AGV forklift through a discharge relay, and the output end of the DCDC module 9 is connected to one end of the forward tilt solenoid valve 10, the rear tilt solenoid valve 11, the distance adjustment solenoid valve one 12, the distance adjustment solenoid valve two 19, the left rotation solenoid valve 13, and the right rotation solenoid valve 14.

[0025] The vehicle controller one 1 is input-connected to the DCDC module 9 and the proximity switch 6 to Figure 2 Taking the rotary flat clamping attachment shown as an example, the proximity switch 6 is installed on the rotary flat clamping attachment and is used to detect whether there is a cargo on the rotary flat clamping attachment. If there is a cargo, the proximity switch 6 closes and outputs a signal of 1; if not, the output signal is 0. The vehicle controller one 1 is output-connected to the inclination sensor 5 and the fault indicator light 18. The inclination sensor 5 is installed on the attachment, and the fault indicator light 18 is installed on the AGV forklift. The inclination sensor 5 is used to detect the tilt angle of the attachment.

[0026] The vehicle controller two 2 is output-connected to the other ends of the forward tilt solenoid valve 10, the rear tilt solenoid valve 11, the distance adjustment solenoid valve one 12, the distance adjustment solenoid valve two 19, the left rotation solenoid valve 13, and the right rotation solenoid valve 14, and is input-connected to the pressure sensor 7, the angle sensor 8, the left laser rangefinder 15, and the right laser rangefinder 16. Taking Figure 2 the rotary flat clamping attachment shown as an example, the pressure sensor 7 is installed on the left clamping arm of the rotary flat clamping attachment and is used to detect the pressure value received by the left clamping arm of the attachment. The angle sensor 8 is installed on the AGV forklift and is used to detect the rotation angle of the attachment when the attachment rotates. Taking Figure 2Taking the shown rotary horizontal clamping attachment as an example, the left laser distance sensor 15 and the right laser distance sensor 16 are both installed at the middle position of the goods retaining shelf of the rotary horizontal clamping attachment. Laser reflectors are installed on the opposite sides of the left clamping arm and the right clamping arm of the rotary horizontal clamping attachment. The two laser reflectors correspond to the left laser distance sensor 15 and the right laser distance sensor 16 respectively. According to the left laser distance sensor 15, the distance N1 between the left clamping arm and the middle position of the goods retaining shelf can be detected. According to the right laser distance sensor 16, the distance N2 between the right clamping arm and the middle position of the goods retaining shelf can be detected. The distance N between the left clamping arm and the right clamping arm of the attachment is N = N1 + N2 (theoretically, N1 = N2 during the opening / closing process of the clamp). According to the detection results of the left laser distance sensor 15 and the right laser distance sensor 16, the relative position and absolute position (i.e., relative to the middle position of the goods retaining shelf of the attachment) of the left clamping arm and the right clamping arm of the attachment can be obtained.

[0027] The input end of the driver 3 is connected to the lithium battery module 17 of the AGV forklift through the main contactor and the discharge relay. The output of the driver 3 is connected to the oil pump motor 4. The driver 3 drives the oil pump motor 4 to act, thereby controlling the attachment to perform actions such as forward tilt, backward tilt, clamping, unclamping, rotation, etc. The vehicle controller issues an execution command according to the detection results of the proximity switch 6, the pressure sensor 7, the angle sensor 8, the left laser distance sensor 15, the right laser distance sensor 16, etc., thereby controlling the driver 3 to drive the oil pump motor 4 to act.

[0028] The AGV forklift is a systematic solution design. Each action requires the confirmation of relevant sensor signals to execute the next step. Through the above control system design, when the AGV forklift is carrying out goods clamping and handling and unclamping and putting down, it detects whether the goods are in place, whether the attachment is clamped, whether the attachment is tilted forward and backward in place, whether the attachment is rotated in place, whether the attachment has been unclamped in place, whether it is extended in place, etc. through sensors before proceeding to the next step. Therefore, the installation of sensors and the accuracy of logical judgment are crucial. For example, on the attachment of the rotary horizontal clamping, the vehicle controller needs to detect whether there are goods, the rotation angle of the attachment, the forward and backward tilt angles of the attachment, the absolute distance and the opening distance between the left and right horizontal clamps, whether it is clamped, etc., and needs to detect and correct it in real time during its movement. And at the end of tilting and rotation, speed reduction processing is required to prevent the goods from being impacted and damaged. When the AGV forklift arrives at the station to carry out goods handling, it is necessary to preset the opening distance of the attachment arm extension, and it is necessary to judge whether the long opening distances of the left and right horizontal clamps are within the deviation range. If the left and right distances meet the requirements, but the long opening distances of the two clamping arms deviate too much, the goods will be pushed down. And if a too large deviation is set, a too large reserved distance between the goods and the goods will be required, wasting warehouse space.

[0029] Specifically, in combination withFigure 3 , based on the above AGV forklift attachment control system, this embodiment provides an AGV forklift attachment control method, which includes the following steps: I. Tilt action control steps (1) Tilt forward to horizontal S11. The VCU issues a horizontal demand command, and the vehicle controller 2 controls the forward tilt solenoid valve 10 to open. The oil pump motor 4 drives the attachment to perform a forward tilt action. The tilt angle sensor 5 continuously collects the current tilt angle of the attachment and obtains the angle deviation value between the current tilt angle and the target tilt angle. S12. Adjust the rotation speed of the oil pump motor 4 according to the current tilt direction and the angle deviation value, and control the valve circuit switch of the oil pump motor 4. S13. When the angle deviation value reaches the first preset difference, that is, when the attachment is approaching the horizontal position, the vehicle controller 1 controls the rotation speed of the oil pump motor 4 to decrease by 50%. S14. When the angle deviation value reaches the second preset difference, the driver 3 controls the oil pump motor 4 to stop; where the second preset difference is less than the first preset difference.

[0030] The entire forward tilt action is completed within 5 s. Otherwise, the vehicle controller 1 controls the fault indicator light 18 to light up, reminding of a vehicle-wide fault.

[0031] (2) Tilt backward S11. The VCU issues a backward tilt demand command, and the vehicle controller 2 controls the backward tilt solenoid valve 11 to open. The oil pump motor 4 drives the attachment to perform a backward tilt action. The tilt angle sensor 5 continuously collects the current tilt angle of the attachment and obtains the angle deviation value between the current tilt angle and the target tilt angle. S12. Adjust the rotation speed of the oil pump motor 4 according to the current tilt direction and the angle deviation value, and control the valve circuit switch of the oil pump motor 4. S13. When the angle deviation value reaches the first preset difference, that is, when the attachment is approaching the backward tilt in-place position, control the rotation speed of the oil pump motor 4 to decrease by 50%. S14. When the angle deviation value reaches the second preset difference, control the oil pump motor 4 to stop; where the second preset difference is less than the first preset difference.

[0032] The entire backward tilt action is completed within 5 s. If the above signals are not satisfied within 5 s, the vehicle controller 1 controls the fault indicator light 18 to light up, reminding of a vehicle-wide fault. The purpose of the 5 s buffer in this embodiment is to prevent the impact of the goods when tilting forward and backward in place.

[0033] II. Cargo clamping action control steps S21. The VCU issues a command for the clamping requirement. The vehicle controller 1 detects the signal of the proximity switch 6 to determine whether there is cargo between the two clamping arms of the attachment. If the signal of the proximity switch is 1, the vehicle controller 2 controls the distance adjustment solenoid valve 12 to open, and the oil pump motor 4 performs a clamping action to make the two clamping arms of the attachment approach each other. S22. The pressure sensor 7 continuously collects the current pressure value that the left clamping arm of the attachment receives due to clamping the cargo, and obtains the pressure deviation value between the current pressure value P and the target pressure value P1. S23. The left laser distance sensor 15 continuously collects the distance N1 between the left clamping arm of the attachment and the middle position of the shelf, and the right laser distance sensor 16 continuously collects the distance N2 between the right clamping arm of the attachment and the middle position of the shelf. The vehicle controller 2 calculates the current distance N = N1 + N2 between the left and right clamping arms of the attachment according to the detection results of the left laser distance sensor 15 and the right laser distance sensor 16, and compares the current distance N with the target distance A. Among them, the target distance A = the width of the cargo + A1, 20 cm ≤ A1 ≤ 30 cm. In this embodiment, A1 = 20 cm. If A1 is too small, the cargo will be pushed when clamping the cargo. If A1 is too large, it will waste the space of the warehouse. S24. When the pressure deviation value reaches the preset difference 3, and the current distance N is less than the target distance A, the oil pump motor 4 stops.

[0034] The entire picking and clamping action is controlled to be completed within 5 s. If the above signals are not satisfied within 5 s, the vehicle controller 1 controls the fault indicator light 18 to light up to remind of the vehicle fault.

[0035] III. Control steps for the unclamping action with cargo Generally, the unclamping action is performed after transporting the cargo to the tray or the fixed position.

[0036] S31. The VCU issues a command for the unclamping requirement. The vehicle controller 2 controls the distance adjustment solenoid valve 19 to open, and the oil pump motor 4 drives the attachment to perform an unclamping action to make the two clamping arms of the attachment move away from each other. S32. The vehicle controller 1 detects the signal of the proximity switch 6 to determine whether there is cargo between the two clamping arms of the attachment. The left laser distance sensor 15 continuously collects the distance N1 between the left clamping arm of the attachment and the middle position of the shelf, and the right laser distance sensor 16 continuously collects the distance N2 between the right clamping arm of the attachment and the middle position of the shelf. The vehicle controller 2 calculates the current distance N = N1 + N2 between the left and right clamping arms of the attachment according to the detection results of the left laser distance sensor 15 and the right laser distance sensor 16, and compares the current distance N with the target distance A. Among them, the target distance = the width of the cargo + A1, 20 cm ≤ A1 ≤ 30 cm. S32. If the signal of proximity switch 6 is 0, and the current distance N between the two clamping arms of the attachment is greater than the target distance A, and N1 > 1 / 2A, N2 > 1 / 2A, control the oil pump motor 4 to stop, complete the unclamping action, and the vehicle can leave.

[0037] The entire unclamping action is controlled to be completed within 5 s. If the above signals are not satisfied within 5 s, the vehicle controller 1 controls the fault indicator light 18 to light up, reminding of the vehicle fault.

[0038] IV. Control Steps for Clamping without Goods S41. The VCU issues a clamping requirement command, and the vehicle controller 2 controls the distance adjustment solenoid valve 12 to open, and the oil pump motor performs a clamping action to make the two clamping arms of the attachment approach each other; S42. The pressure sensor 7 continuously collects the current pressure value P that the left clamping arm of the attachment receives due to being squeezed by the other clamping arm, and compares the current pressure value P with the target pressure value P1; S43. The vehicle controller 1 detects the signal of the proximity switch 6 to determine whether there is goods between the two clamping arms of the attachment; the left laser distance sensor 15 continuously collects the distance N1 between the left clamping arm of the attachment and the middle position of the goods shelf, and the right laser distance sensor 16 continuously collects the distance N2 between the right clamping arm of the attachment and the middle position of the goods shelf. The vehicle controller 2 calculates the current distance N = N1 + N2 between the left and right clamping arms of the attachment according to the detection results of the left laser distance sensor 15 and the right laser distance sensor 16, and compares the current distance N with the target distance W1; where the target distance W1 is the minimum distance between the clamping arms of the attachment in the clamped state; S44. When the current pressure value P is greater than the target pressure value P1, and the current distance N is equal to the target distance W1, then control the oil pump motor to stop.

[0039] The entire clamping action is controlled to be completed within 5 s. If the above signals are not satisfied within 5 s, the vehicle controller 1 controls the fault indicator light 18 to light up, reminding of the vehicle fault.

[0040] V. Control Steps for Unclamping without Goods (i.e., Clamping Open Action) S51. The VCU issues an unclamping requirement command, and the vehicle controller 2 controls the distance adjustment solenoid valve 19 to open, and the oil pump motor 4 drives the attachment to perform an unclamping action to make the two clamping arms of the attachment move away from each other; S52. The left laser distance sensor 15 collects in real time the distance N1 between the left clamping arm of the attachment and the middle position of the retaining shelf. The right laser distance sensor 16 collects in real time the distance N2 between the right clamping arm of the attachment and the middle position of the retaining shelf. The vehicle controller II calculates the current distance N between the left and right clamping arms of the attachment as N = N1 + N2 based on the detection results of the left laser distance sensor 15 and the right laser distance sensor 16, and compares the current distance N with the target distance W2; among them, the target distance W2 is the maximum distance between the clamping arms of the attachment in the clamping and opening state. S52. When the current distance N between the two clamping arms of the attachment is equal to the target distance W2, control the oil pump motor 4 to stop.

[0041] The entire clamping and opening action is controlled to be completed within 5 s. If the above signals are not satisfied within 5 s, the vehicle controller I 1 controls the fault indicator light 18 to light up, reminding of a vehicle-wide fault.

[0042] VI. Control steps for the load-carrying rotation action S61. The VCU issues a left / right rotation command. The pressure sensor 7 collects in real time the current pressure value P that the left clamping arm of the attachment receives due to clamping the goods, and compares the current pressure value P with the target pressure value P1; when the current pressure value P is greater than the target pressure value P1, the vehicle controller II 2 controls the left rotation solenoid valve 13 or the right rotation solenoid valve 14 to open, and the oil pump motor 4 drives the attachment to rotate left / right. S62. The angle sensor 8 collects in real time the current rotation angle of the attachment, and obtains the rotation angle deviation value between the current rotation angle and the target rotation angle. S63. When the rotation angle deviation value is within the range of ±0.5°, the vehicle controller II 2 controls the left rotation solenoid valve 13 or the right rotation solenoid valve 14 to lock, and stops the rotation operation.

[0043] The entire load-carrying rotation action is controlled to be completed within 5 s. If the above signals are not satisfied within 5 s, the vehicle controller I 1 controls the fault indicator light 18 to light up, reminding of a vehicle-wide fault.

[0044] VII. Control steps for the no-load rotation action S71. The VCU issues a left / right rotation command. The vehicle controller II 2 controls the left rotation solenoid valve 13 or the right rotation solenoid valve 14 to open, and the oil pump motor 4 drives the attachment to rotate left or right. S72. The angle sensor 8 collects in real time the current rotation angle of the attachment, and obtains the rotation angle deviation value between the current rotation angle and the target rotation angle. S73. When the rotation angle deviation value is within the range of ±0.5°, the vehicle controller II 2 controls the left rotation solenoid valve 13 or the right rotation solenoid valve 14 to lock, and stops the rotation operation.

[0045] The entire no-load rotation action is controlled to be completed within 5 s. If the above signals are not satisfied within 5 s, the vehicle controller 1 controls the fault indicator light 18 to light up, reminding of the vehicle fault.

[0046] VIII. This embodiment can also perform side shift control on the left and right clamping arms of the attachment. Specifically: The VCU issues a command for the left or right side shift requirement of the clamping arm, and the oil pump motor 4 drives the left or right side shift of the clamping arm of the attachment; the left laser distance sensor 15 continuously collects the distance N1 between the left clamping arm of the attachment and the middle position of the shelf, and the right laser distance sensor 16 continuously collects the distance N2 between the right clamping arm of the attachment and the middle position of the shelf. According to the detection results of the left laser distance sensor 15 and the right laser distance sensor 16, the positions of the left and right clamping arms are monitored in real time and a closed-loop control is formed.

[0047] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0048] The above-described embodiments only represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent should be subject to the appended claims.

Claims

1. A method for controlling an AGV forklift attachment, characterized in that: The method comprises a tilting motion control step of the attachment, wherein the tilting motion control step comprises: S11. Control the oil pump motor to drive the attachment to tilt forward or backward, obtain the current tilt angle of the attachment in real time, and obtain the angle deviation value between the current tilt angle and the target tilt angle; S12. Adjust the oil pump motor speed of the AGV forklift according to the current tilt direction and the angle deviation value; S13. When the angle deviation value reaches a preset difference value of one, the oil pump motor speed is controlled to decrease; S14. When the angle deviation value reaches the preset difference value 2, the oil pump motor is controlled to stop; wherein the preset difference value 2 is less than the preset difference value 1; S15. The entire tilting action is controlled to be completed within the preset time, otherwise a fault reminder is given after the preset time.

2. The AGV forklift attachment control method according to claim 1, characterized in that: The AGV forklift attachment control method further includes a cargo holding action control step of the attachment, and the cargo holding action control step includes: S21. Detecting the cargo signal between the two clamping arms of the attachment; if there is a cargo signal between the two clamping arms of the attachment, controlling the oil pump motor to drive the attachment to perform a clamping action so that the two clamping arms of the attachment are close to each other; S22. Obtain the current pressure value of the two clamping arms of the attachment, and obtain the pressure deviation value between the current pressure value and the target pressure value; S23. Obtain the distance between the two clamping arms of the attachment and the center position of the attachment and use it to calculate the current distance between the two clamping arms of the attachment, and compare the current distance with the target distance - A; wherein the target distance - A = cargo width + A1, 20cm≤A1≤30cm; S24. When the pressure deviation value reaches the preset difference value 3, the current spacing is less than the target spacing 1A, and the distance between the two clamping arms of the attachment and the center position of the attachment is less than 1 / 2A, the oil pump motor is controlled to stop; S25. The entire cargo holding action is controlled to be completed within the scheduled time, otherwise a fault reminder is given after the scheduled time.

3. The AGV forklift attachment control method according to claim 1, characterized in that: The AGV forklift attachment control method further includes a cargo-releasing action control step of the attachment, and the cargo-releasing action control step includes: S31. Control the oil pump motor to drive the attachment to release the clamp so that the two clamp arms of the attachment move away from each other; S32. Real-time detection of cargo signals between the two clamping arms of the attachment, obtaining the distance between the two clamping arms of the attachment and the center position of the attachment and using it to calculate the current spacing between the two clamping arms of the attachment, and comparing the current spacing with the target spacing 1; wherein the target spacing 1 = cargo width + A1, 20cm≤A1≤30cm; S32. If the cargo signal between the two clamping arms of the attachment disappears, the current distance between the two clamping arms of the attachment is greater than the target distance -A, and the distance between the two clamping arms of the attachment and the center position of the attachment is greater than 1 / 2A, the oil pump motor is controlled to stop; S33. The entire unclamping action is controlled to be completed within the scheduled time, otherwise a fault reminder will be issued after the scheduled time.

4. The AGV forklift attachment control method according to claim 1, characterized in that: The AGV forklift attachment control method further includes a step of controlling an attachment's empty cargo holding action, and the empty cargo holding action control step includes: S41. Control the oil pump motor to drive the attachment to perform a clamping action so that the two clamping arms of the attachment are close to each other; S42. Obtain the current pressure value of the two clamping arms of the attachment, and compare the current pressure value with the target pressure value; S43. Obtain the distance between the two clamping arms of the attachment and the center position of the attachment and use it to calculate the current distance between the two clamping arms of the attachment, and compare the current distance with the target distance 2; wherein the target distance 2 is the minimum distance between the clamping arms of the attachment in the clamping state; S44. When the current pressure value is greater than the target pressure value and the current spacing is equal to the target spacing 2, the oil pump motor is controlled to stop; S45. The entire empty cargo holding action is controlled to be completed within the scheduled time, otherwise a fault reminder is issued after the scheduled time.

5. The AGV forklift attachment control method according to claim 1, characterized in that: The AGV forklift attachment control method further includes a step of controlling the attachment to release the clamp when there is no cargo, and the step of controlling the attachment to release the clamp when there is no cargo includes: S51. Control the oil pump motor to drive the attachment to release the clamp so that the two clamp arms of the attachment move away from each other; S52. Real-time acquisition of the distance between the two clamping arms of the attachment and the center position of the attachment and calculation of the current spacing between the two clamping arms of the attachment, and comparison of the current spacing with the target spacing three; wherein the target spacing three is the maximum distance between the clamping arms of the attachment in the clamping state; S52. If the current distance between the two clamping arms of the attachment is equal to the target distance three, the oil pump motor is controlled to stop; S53. The entire tilting action is controlled to be completed within the preset time, otherwise a fault reminder is issued after the preset time.

6. The AGV forklift attachment control method according to claim 1, characterized in that: The AGV forklift attachment control method further includes a step of controlling a load-carrying rotation action of the attachment, and the step of controlling a load-carrying rotation action includes: S61. Obtain the current pressure value of the two clamping arms of the attachment, and compare the current pressure value with the target pressure value; when the current pressure value is greater than the target pressure value, control the oil pump motor to drive the attachment to rotate left or right; S62. Obtain the current rotation angle of the attachment in real time, and obtain the rotation angle deviation value between the current rotation angle and the target rotation angle; S63. When the rotation angle deviation value reaches a preset difference of four, the oil pump motor is controlled to stop; S64. The entire loaded rotation action is controlled to be completed within the preset time, otherwise a fault reminder is issued after the preset time.

7. The AGV forklift attachment control method according to claim 1, characterized in that: The AGV forklift attachment control method further includes a no-load rotation action control step of the attachment, and the no-load rotation action control step includes: S71. Control the oil pump motor to drive the attachment to rotate left or right; S72. Obtain the current rotation angle of the attachment in real time, and obtain the rotation angle deviation value between the current rotation angle and the target rotation angle; S73. When the rotation angle deviation reaches a preset difference of four, the oil pump motor is controlled to stop; S74. The entire no-load rotation action is controlled to be completed within the preset time, otherwise a fault reminder is issued after the preset time.

8. An AGV forklift attachment control system, characterized in that: The method adopts the AGV forklift attachment control method as claimed in any one of claims 1 to 7, which comprises: a vehicle controller, which is used to control the operation of the oil pump motor and adjust the speed of the oil pump motor; and The inclination sensor is used to detect the inclination angle of the attachment.

9. The AGV forklift attachment control system according to claim 8, characterized in that: It also includes: A proximity switch, which is used to detect whether there is cargo between the two clamping arms of the attachment; A pressure sensor, used to detect the pressure value of the clamping arm of the attachment; Two distance measuring sensors, the two distance measuring sensors are used to detect the distance between the two clamping arms of the attachment and the center position of the attachment respectively; and An angle sensor is used to detect the rotation angle of the attachment.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by the processor, the steps of the AGV forklift attachment control method according to any one of claims 1 to 7 are implemented.

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