CN114475273B

CN114475273B - AGV and driving control method thereof

Info

Publication number: CN114475273B
Application number: CN202210092240.3A
Authority: CN
Inventors: 崔俊健
Original assignee: Guangdong Jaten Robot and Automation Co Ltd
Current assignee: Guangdong Jaten Robot and Automation Co Ltd
Priority date: 2022-01-26
Filing date: 2022-01-26
Publication date: 2024-08-16
Anticipated expiration: 2042-01-26
Also published as: CN114475273A

Abstract

The invention belongs to the technical field of automatic navigation vehicles, in particular to a driving control method of an AGV and the AGV, wherein the driving controller of the invention is used for driving a motor and simultaneously serving as a lower computer to be in communication connection with an upper computer, when a traveling command is executed, the upper computer outputs specific traveling parameters, the driving controller outputs control instructions to two motors according to the traveling parameters, the real-time steering angle of a driving unit and the real-time speeds of two driving wheels, and the real-time steering angle and the real-time speeds of the two driving wheels fed back are received constantly, so that each driving unit can meet the running parameters output by the upper computer constantly, closed-loop control and independent control of each driving unit are realized, the load of the upper computer is reduced, the phenomena of too slow data processing, delay and the like caused by the increase of the driving units are avoided, and the phenomena of signal delay, drifting, interference and the like of the motor are avoided, so that the AGV with large length and higher bearing can be built by utilizing the driving unit combination.

Description

AGV and driving control method thereof

Technical Field

The invention belongs to the technical field of automatic navigation vehicles, and particularly relates to an AGV and a driving control method thereof.

Background

The existing AGV comprises a frame and a plurality of differential driving units arranged at the bottom of the frame, wherein the driving units comprise a main frame, two driving wheels and two motors, the motors are driven by a driver, each driving wheel is driven to rotate through one motor, the steering and straight running of the driving units are realized by controlling the speed difference of the two driving wheels during running, an upper computer used for being connected with the driving units in a communication mode is arranged on the frame, the upper computer directly controls the running of each driving unit during task execution, therefore, the upper computer is required to output control instructions to the driving units and process data returned by the driving units, when the number of the driving units is large and the relative interval distance is long, phenomena such as too slow data processing, delay and the like can occur, and accordingly, the phenomena such as signal delay, drifting, interference and the like can occur between the driver and the motors.

Disclosure of Invention

The invention aims to overcome the defects of slow data processing and delay of an upper computer of the existing AGV, and provides a driving control method for controlling respective motors through a driving unit so as to improve the data processing speed.

In order to solve the technical problems, the invention adopts the following technical scheme:

the utility model provides a drive control method of AGV, relates to AGV includes host computer, frame, support a plurality of drive unit in the frame bottom, every drive unit all be equipped with two power modules of relative setting and with the drive controller of host computer communication connection, power module include the action wheel and drive the rotatory motor of action wheel, drive controller is according to the running parameter of host computer output to through obtaining the real-time steering angle of drive unit and the real-time speed of two action wheels, with respectively to two motor output control command, make drive unit's steering angle and running speed satisfy the running parameter.

Compared with the prior art, the driving control method provided by the invention has the advantages that the driving controller is arranged on each driving unit, the driving controller is used as a lower computer to be in communication connection with an upper computer while driving the motor, and when a traveling command is executed, the upper computer outputs specific traveling parameters, the driving controller outputs control instructions to the two motors according to the traveling parameters, the real-time steering angle of the driving units and the real-time speeds of the two driving wheels, and receives the feedback real-time steering angle and the real-time speeds of the two driving wheels at any moment, so that each driving unit can meet the traveling parameters output by the upper computer at any moment, the closed-loop control is realized, the independent control of each driving unit is realized, the load of the upper computer is reduced, the phenomena of too slow data processing, delay and the like can not occur due to the increase of the driving units, the designed distance of each driving unit on the AGV is basically not limited, the AGV with the driving unit combination has a large building length and higher bearing capacity, and the phenomena of signal delay, drifting, interference and the like of the motor are avoided.

Further, the driving parameters include a steering angle θ and a speed V;

the real-time steering angle of the driving unit is thetan, the real-time speeds of the two driving wheels are Vn1 and Vn2 respectively, and the control instruction comprises:

When θ=θn and when V is not equal to 0, let vn1= vn2=v;

when θ is not equal to θn and V is not equal to 0, calculating an adjustment value x according to the difference between θ and θn, so that vn1=v and vn2=v+x;

When θ+.θn and v=0, the steering given value y is calculated from the difference between θ and θn, so that vn1=vn2=y, where Vn1 and Vn2 are opposite in direction.

Further, the upper computer outputs corresponding driving parameters to each driving unit respectively.

Further, the driving controller is in communication connection with the upper computer through a CAN line.

The invention also provides an AGV applying the driving control method, which comprises an upper computer, a frame and a plurality of driving units supported at the bottom of the frame, wherein each driving unit is provided with two power modules which are oppositely arranged and a driving controller which is in communication connection with the upper computer, and each power module comprises a driving wheel and a motor for driving the driving wheel to rotate.

Drawings

Fig. 1 is a schematic structural view of a driving unit;

fig. 2 is a schematic structural view of the driving unit;

FIG. 3 is a partially exploded view of a hydraulic lift device;

FIG. 4 is a schematic view of the structure of the support member in the first position;

FIG. 5 is a schematic view of the structure of the support member in the second position;

FIG. 6 is a schematic structural view of an AGV;

FIG. 7 is a block diagram of the drive controller and the host computer;

fig. 8 is a flow chart of the drive unit implementing closed loop control.

Detailed Description

The following describes specific embodiments of the present invention with reference to the drawings. In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

Referring to fig. 1 to 8, the present embodiment provides a driving control method for an AGV and an AGV applying the driving control method, where the AGV includes an upper computer 9, a frame 7, and a plurality of driving units 100 supported at the bottom of the frame 7, each driving unit 100 is provided with a driving controller 8 for controlling two motors 33 in a one-to-two mode, the driving units 100 are provided with encoders 635 for collecting corresponding real-time steering angles, and the driving controller 8 simultaneously receives and processes real-time steering angle signals fed back by the encoders 635 and obtains real-time speeds of two driving wheels 32, and is in communication connection with the upper computer 9 through can wires.

The driving controller 8 serves as a role of a lower computer, and directly outputs speed control commands to the two motors 33 according to the running parameters (speed V and steering angle θ) output by the upper computer 9, the signals fed back by the encoder 635, and the real-time speeds of the two driving wheels 32, so that the steering angle and the running speed of the driving unit meet the running parameters at the moment, thereby realizing closed-loop control and realizing the movement of the AGV in multiple directions, and specifically comprises the following steps:

The upper computer 9 outputs control parameters to each driving unit 100 respectively including a steering angle θ and a speed V, where the control parameters output by the upper computer 9 to each driving unit 100 may be the same or different, as shown in fig. 7, the upper computer outputs steering angles V1 and θa to the driving unit one and outputs steering angles V2 and θb to the driving unit two, the driving controller 8 of each driving unit 100 obtains a real-time steering angle θn of the corresponding driving unit 100 and real-time speeds Vn1 and Vn2 of the two driving wheels 32, as shown in fig. 7, the driving controller 1 obtains a real-time steering angle θ1 of the driving unit one, a real-time speed V11 of the driving wheel a, and a real-time speed V12 of the driving wheel B, and the driving controller 2 obtains a real-time steering angle θ2 of the driving unit two, a real-time speed V21 of the driving wheel C, and a real-time speed V22 of the driving wheel D, and outputs control instructions according to the control parameters (as shown in fig. 8):

when θ=θn and v+.0, vn1=vn2=v, and drive unit 100 is driven at speed V and at the original steering angle;

When θ is not equal to θn and V is not equal to 0, calculating an adjustment value x according to the difference between θ and θn, so as to enable vn1=v and vn2=v+x, and enabling the driving unit 100 to turn at a speed V for θ;

When θ+.θn and v=0, the steering given value y is calculated from the difference between θ and θn, so that vn1=vn2=y, where Vn1 and Vn2 are opposite in direction, the driving unit 100 is steered in place by θ degrees.

The calculation method of the adjustment value x and the steering target value y is not an invention point of the present invention, and is not described here.

According to the AGV, the driving controller 8 is arranged on each driving unit 100, the driving controller 8 is also used as a lower computer to be in communication connection with the upper computer 9 when driving the motor 33, and when a running command is executed, the upper computer 9 outputs specific speed and steering parameters, the driving controller 8 outputs control instructions to the two motors 33 according to the running parameters output by the upper computer 9, the real-time steering angle of the driving units 100 and the real-time speeds of the two driving wheels 32, and receives feedback real-time steering angle signals and real-time speeds of the two driving wheels 32 constantly to dynamically adjust, so that each driving unit 100 meets the running parameters output by the upper computer 9 constantly, independent control of each driving unit 100 is realized, and therefore, the load of the upper computer 9 is reduced, the phenomena of too slow data processing, delay and the like can not occur due to the increase of the driving units 100, the designed distance of each driving unit 100 is basically unlimited, meanwhile, the AGV with the combined length of the driving units 100 is utilized, and the phenomena of building of the motor 33, the delay, the occurrence of the interference signals and the like are avoided.

Referring to fig. 1 and 2, the driving unit is used for supporting the bottom of the frame 7 of the AGV, and comprises a main frame 1 and two power modules 2, wherein the opposite sides of the main frame 1 are respectively provided with an installation position 11 extending inwards, the two power modules 2 are respectively installed in the installation positions 11 on the corresponding sides, the power modules 2 respectively comprise a secondary frame 21, a driving wheel assembly 3 and a driven wheel assembly 4, the two side walls of the installation position 11 are respectively hinged with the opposite sides of the secondary frame 21 through first pin shafts 01, the hinged positions of the two side walls form a first rotation axis 101, the driving wheel assembly 3 is relatively fixedly arranged on the side, away from the main frame 1, of the secondary frame 21, and the driven wheel assembly 4 is arranged on the side, close to the main frame 1, of the secondary frame 21.

Referring to fig. 1 and 2, the driven wheel assembly 4 includes a tertiary frame 41, a quaternary frame 42 disposed within the tertiary frame 41, and a driven wheel group 43 disposed within the quaternary frame 42, opposite sides of the secondary frame 21 being hinged to opposite sides of the tertiary frame 41 at a side of the first rotational axis 101 near a middle portion of the primary frame 1 by a second pin 02, the hinge forming a vertical second rotational axis 102 spaced apart from the first rotational axis 101 by a horizontal distance, opposite sides of the quaternary frame 42 being hinged to the middle portion of the tertiary frame 41 by a third pin 03, the hinge forming a third rotational axis 103 perpendicular to the second rotational axis 102, the hinge between the tertiary frame 41 and the secondary frame 21 allowing the driven wheel assembly 4 to rotate about the second rotational axis 102, the hinge between the quaternary frame 42 and the tertiary frame 41 allowing the quaternary frame 42 to rotate about the third rotational axis 103 with the driven wheel group 43 therein, the rotational axes formed by the pins providing effective support for the respective frames.

Referring to fig. 1 and 2, the driving wheel assembly 3 includes a mounting frame 31, a driving wheel 32 and a motor 33 for driving the driving wheel 32 to rotate, fourth pin shafts 04 hinged with the mounting frame 31 are respectively arranged on opposite sides of the driving wheel 32, the motor 33 is arranged on the outer side of the mounting frame 31, the fourth pin shafts 04 are located on one side close to the motor 33 and are directly connected with the output end of the motor 33, and compared with the existing belt transmission mode, the driving precision is higher and more durable.

The AGV driving unit is provided with the secondary frames 21 positioned on two opposite sides of the main frame 1, the secondary frames 21 are rotationally connected with the main frame 1, the driving wheel assemblies 3 and the driven wheel assemblies 4 are arranged on two opposite sides of the secondary frames 21, the driven wheel assemblies 4 are added between the driving wheel assemblies 3 and the main frame 1, the downward force applied by loads can be shared, effective support is provided for the AGV frame, the load of the driving wheel 32 is reduced, the service life of the driving wheel 32 is prolonged, after the driven wheel assemblies 4 are added, the force arm from the driving wheel 32 to the center of the driving unit is correspondingly increased, therefore, the wheel diameter of the driving wheel 32 and the rotation moment of the driving unit can be reduced on the basis, the cost is reduced, the distance from the frame to the bottom surface is reduced as much as possible, the gravity center of the AGV is lower, the running is more stable, and meanwhile, the flexible frame formed among the main frame 1, the secondary frame 21 and the tertiary frame 41 can ensure AGV to avoid bearing too much rigid impact, and the service life of the driving unit is prolonged.

Referring to fig. 1, as an improved arrangement, the secondary frame 21 extends outward from the mounting location 11 to enable the driving wheel assembly 3 to be disposed outside the main frame 1, thereby further extending the arm of force of the driving wheel 32, and on the basis of this, the housing further reduces the size of the driving wheel 32 to reduce the cost.

Referring to fig. 1, as a specific arrangement, the tertiary frame 41 is provided with at least two assembly areas 44 arranged in parallel along the third rotation axis 103, each assembly area 44 is provided with one of the quaternary frames 42, the driven wheel groups 43 in each quaternary frame 42 include a plurality of driven wheels 431 symmetrically arranged at two sides of the third rotation axis 103, and each quaternary frame 42 forms an independent flexible module, and each quaternary frame 42 can independently rotate around the third rotation axis 103 according to the corresponding road condition, so that the adaptability of the driving unit to the road surface is further improved, the load can be effectively supported, and the daily maintenance is more convenient.

Referring to fig. 1,2, 4 and 5, as an improved manner, the driving wheel assembly 3 further includes a supporting member 34 that can be manipulated to move up and down relative to the driving wheel, in a specific manner, the supporting member 34 is movably assembled on the mounting frame 31 up and down, as shown in fig. 4, the supporting member 34 has a first position in which the bottom of the supporting member protrudes downward below the bottom of the driving wheel, and a second position in which the bottom of the supporting member protrudes upward above the bottom of the driving wheel, as shown in fig. 5, a first limiting mechanism 12 is disposed between the main frame 1 and the secondary frame 21 corresponding to the first position, when the supporting member 34 moves to the first position, the power module 2 can swing up around the first rotation axis 101, and through the first limiting mechanism 12, an angle after the upward swing of the power module 2 can be locked, when the supporting member 34 moves to the second position and unlocks the first limiting mechanism 12, the power module 2 can swing down around the first rotation axis 101, and when the driving wheel 32 needs to leave the ground, the driven wheel 32 moves down to the lower side of the driving wheel 21, and the secondary frame 21 can swing up and the secondary frame 21 can always swing up and keep close to the second position along with the first rotation axis 32, and the second limiting mechanism can swing up and keep the second position between the driving wheel and the secondary frame 21.

Referring to fig. 4 and 5, as a specific embodiment, the first limiting mechanism 12 is a pin hole formed on the main frame 1 and the secondary frame 21, and a pin detachably engaged with the pin hole, and when the two pin holes are aligned, the pin is inserted into the two pin holes, the secondary frame 21 with a swing angle can be fixed, and after the pin is pulled out, the secondary frame 21 can swing downward to reset.

Referring to fig. 1 and 2, as a specific embodiment, the driving unit further comprises a rotary seat 5 provided in the middle of the main frame 1, and a suspension assembly 6 provided on the rotary seat 5, the rotary seat 5 being rotatable about a fourth rotation axis 104 provided in the middle of the main frame 1 and parallel to the first rotation axis 101, the suspension assembly 6 comprising a slewing bearing 61, a guide cylinder 62 and a hydraulic lifting device, the slewing bearing 61 comprising an inner ring 611 and an outer gear 612 rotatable relative to the inner ring 611, the outer gear 612 being fixedly connected to the rotary seat 5, the guide cylinder 62 being fixedly provided on the upper side of the inner ring 611 of the slewing bearing 61, and being provided with an upper side opening chamber, the hydraulic lifting device comprising a cylinder body 631 slidably fitted with the chamber of the guide cylinder 62, a piston rod 632 provided in the cylinder body 631, a bracket 633 provided on the outer side of the guide cylinder 62 and fixedly connected to the cylinder 631, a power station 634 and an encoder 635 provided on the bracket 633, the cylinder body 631 being connected to the bottom of the frame 631, the end of the piston rod 632 being fixedly connected to the inner side wall 62, the inner side of the guide cylinder 631 being provided with an oil duct 63636, the guide cylinder mount being provided with an oil duct 63636 being inserted into the upper side of the guide cylinder 631, the guide cylinder being provided with an oil duct 6364, the piston rod 63being inserted into the upper side of the guide cylinder 631, the guide cylinder 631 being provided with an oil duct 636, and the guide duct 63being inserted into the upper side of the guide duct 637 by way, and being moved by the power station 631, and the piston rod 631 being inserted into the upper side of the power station, by combining the connection mode between the slewing bearing 61 and the guide cylinder 62 and the rotating seat 5, the hydraulic lifting device and the main frame 1 can be ensured to relatively rotate, so that when the driving unit turns, the hydraulic lifting device and the frame of the AGV can not rotate along with the rotation of the main frame 1 due to lateral force, thereby avoiding the increase of loss caused by rotation and pulling between the power station 634 and the oil circuit 636, reducing the risk of oil leakage and effectively prolonging the service life of the driving unit. Meanwhile, the adaptability of the driving unit to the ground road conditions can be further improved by the arrangement of the rotating seat 5, the AGV is ensured to run stably, and the encoder 635 can accurately acquire the real-time steering angle of the driving unit through the rotation of the external gear 612 along with the main frame 1, and the steering angle of the driving unit is the angle of the main frame 1 relative to the central axis of the guide cylinder 62.

Referring to fig. 1 and 2, as a specific arrangement, the main frame 1 includes two transverse plates 13 disposed opposite to each other, and two vertical plates 14 disposed at a middle portion of the two transverse plates 13 at intervals, the rotating base 5 includes a rotating shaft 51 rotatably connected to the two transverse plates 13 and disposed between the two vertical plates 14, and a supporting plate 52 fixedly connected to the rotating shaft 51, and the supporting plate 52 is fixedly connected to the external gear 612.

Variations and modifications to the above would be obvious to persons skilled in the art to which the invention pertains from the foregoing description and teachings. Therefore, the invention is not limited to the specific embodiments disclosed and described above, but some modifications and changes of the invention should be also included in the scope of the claims of the invention. In addition, although specific terms are used in the present specification, these terms are for convenience of description only and do not limit the present invention in any way.

Claims

The AGV is characterized by comprising a main frame, an upper computer, a frame and a plurality of driving units supported at the bottom of the frame, wherein each driving unit is provided with two power modules which are arranged oppositely and a driving controller which is in communication connection with the upper computer, each power module comprises a driving wheel and a motor which drives the driving wheel to rotate, the power modules are arranged at two opposite sides of the main frame, the main frame is provided with encoders, the encoders are provided with encoder gears which rotate along with the main frame, and the encoder calculates the steering angle of the driving unit through the rotation angle of the encoder gears;

The two power modules can be respectively arranged on two opposite sides of the main frame in a rotating way around a first rotation axis, and each power module comprises:

-a secondary frame rotatably connected to said main frame;

-a drive wheel assembly arranged relatively fixedly on the side of the secondary frame remote from the primary frame, the drive wheel assembly comprising a drive wheel and a motor for driving the drive wheel in rotation;

-a driven wheel assembly rotatably arranged on the secondary frame at a side close to the main frame about a vertical second axis of rotation spaced apart from the first axis of rotation, said driven wheel assembly comprising:

-a tertiary frame rotatably connected to said secondary frame;

-a four-stage frame rotatably arranged in said three-stage frame about a third rotation axis perpendicular to said second rotation axis, said four-stage frame being internally driven wheelsets;

the driving wheel assembly also comprises a supporting piece which can be controlled to move up and down relative to the driving wheel, the supporting piece is provided with a first position which enables the bottom of the supporting piece to protrude downwards below the bottom of the driving wheel and a second position which enables the bottom of the supporting piece to move upwards above the bottom of the driving wheel, a first limit structure is arranged between the main frame and the secondary frame corresponding to the first position, the power module can swing upwards relative to the main frame around the first rotation axis when the supporting piece moves to the first position, the angle after the power module swings upwards can be locked through the first limit structure, and the power module can swing downwards relative to the main frame around the first rotation axis when the supporting piece moves to the second position and is unlocked.
2. The AGV of claim 1, wherein the drive unit further includes a suspension assembly disposed on an upper side of the main frame, the suspension assembly including:

-a slewing bearing comprising an inner ring and an outer gear rotatable relative to the inner ring, the outer gear being fixedly connected to the main frame;

-a guiding cylinder fixed to the upper side of the inner ring, provided with a chamber open on the upper side;

The hydraulic lifting device comprises a cylinder body, a piston rod, a support, a power station and an encoder, wherein the cylinder body is in sliding fit with a cavity of the guide cylinder, the piston rod is arranged in the cylinder body, the support is positioned at the outer side of the guide cylinder and fixedly connected with the cylinder body, the power station and the encoder are arranged on the support, the cylinder body is connected to the bottom of the frame, the end part of the piston rod is fixedly connected with the inner bottom wall of the guide cylinder, the cylinder body is provided with an oil way for connecting the power station and an inner cavity of the power station, a sliding groove extending towards the upper side is formed in the side part of the guide cylinder, a limiting block is arranged at the outer side of the cylinder body and is inserted into the sliding groove, and the encoder gear is meshed with the outer gear.
3. The AGV of claim 1 wherein said tertiary frame has at least two mounting areas juxtaposed along said third axis of rotation, each of said mounting areas having one of said quaternary frames disposed therein, said driven wheel sets in each quaternary frame including a plurality of driven wheels symmetrically disposed on either side of said third axis of rotation.
4. The drive control method applied to the AGV according to any one of claims 1 to 3 wherein the drive controller is configured to output control instructions to the two motors by acquiring a real-time steering angle of the drive unit and a real-time speed of the two driving wheels according to the running parameters output by the host computer, so that the steering angle and the running speed of the drive unit satisfy the running parameters at any time.
5. The drive control method according to claim 4, characterized in that the running parameters include a steering angle θ and a speed V;

the real-time steering angle of the driving unit is thetan, the real-time speeds of the two driving wheels are Vn1 and Vn2 respectively, and the control instruction comprises:

When θ=θn and when V is not equal to 0, let vn1= vn2=v;

when θ is not equal to θn and V is not equal to 0, calculating an adjustment value x according to the difference between θ and θn, so that vn1=v and vn2=v+x;

When θ+.θn and v=0, the steering given value y is calculated from the difference between θ and θn, so that vn1=vn2=y, where Vn1 and Vn2 are opposite in direction.
6. The drive control method according to claim 5, wherein the host computer outputs the corresponding running parameters to the respective drive units.
7. The drive control method according to claim 4, wherein the drive controller is communicatively connected to the host computer via a CAN line.