CN109079738B

CN109079738B - Self-adaptive AGV robot and self-adaptive navigation method

Info

Publication number: CN109079738B
Application number: CN201810972830.9A
Authority: CN
Inventors: 唐悦; 卢展宏
Original assignee: Beijing Mita Network Technology Co ltd
Current assignee: Shanghai Mita Network Technology Co ltd
Priority date: 2018-08-24
Filing date: 2018-08-24
Publication date: 2022-05-06
Anticipated expiration: 2038-08-24
Also published as: CN109079738A

Abstract

The invention belongs to the technical field of robots, and discloses a self-adaptive AGV robot and a self-adaptive navigation method, wherein the self-adaptive AGV robot comprises a vehicle body, a navigation device arranged on the vehicle body and an execution device arranged on the vehicle body; the navigation device comprises a detection radar, a detection camera and a processor, and is used for planning the traveling path of the robot and actively avoiding obstacles on the path; the executing mechanism comprises a base, a cooperation mechanical arm and an executing steering engine, wherein the cooperation mechanical arm comprises a first driving box, a four-bar mechanism, a second driving box, a sleeve shaft mechanical arm, a tail end transmission head and a tail end executing head, and therefore a six-degree-of-freedom executing structure is formed. Under the guidance of the vehicle body bearing and navigation device, the robot can freely walk in an indoor environment to drive the execution mechanism to execute tasks. The invention has small dead weight and low cost, can realize more flexible path planning compared with the similar cooperative robots, and the cooperative mechanical arm has longer arm extension and larger load and good expandability.

Description

Self-adaptive AGV robot and self-adaptive navigation method

Technical Field

The invention belongs to the technical field of cooperative robots, and particularly relates to a self-adaptive AGV robot and a self-adaptive navigation method.

Background

An AGV (Automated Guided Vehicle) is a Vehicle equipped with an electromagnetic or optical automatic guide device, which can travel along a predetermined guide path and has various transfer functions as safety protection. AGV wide application is in storage transport and manufacturing transport, and comparatively advanced AGV still is applied to dangerous place and special industry.

The conventional AGV frame basically adopts structures such as wheel type movement and belt type movement, so that the vehicle body can freely advance and turn in a narrow space conveniently. However, the traveling and steering modes of the conventional AGV frame are basically hinge-shaft steering, the steering mechanism has a certain limitation on application space due to the fact that the minimum steering radius of the steering mechanism is limited, and in most of limited spaces, the AGV adopting the hinge-shaft steering mechanism is difficult to pass through smoothly at one time and even cannot pass through, so that the AGV is applied to a large problem.

And the mechanical arm of the cooperative robot is a complex system with multiple inputs and multiple outputs, high nonlinearity and strong coupling. Because of the unique operation flexibility, the method is widely applied to the fields of industrial assembly, safety, explosion prevention and the like; along with the research and development of the stretching of the mechanical arm, the structure and the precision of the mechanical arm are greatly improved, the mechanical arm is not only applied in the current field, but also expanded to a plurality of technical fields for directly assisting people to operate, even can partially replace the work of people, and in a plurality of industrial fields including sensitive environments and complex environments, the application of the mechanical arm in cooperation can protect personnel, ensure the production quality, improve the efficiency and reduce the equipment damage. For example, in the field of Automated Guided Vehicles (AGVs), a cooperative mechanical arm can be used in cooperation with an AGV to participate in various processes of production automation, such as stacking, sorting, visual inspection, and the like.

The indexes of the current cooperative mechanical arm, such as speed, rigidity, working radius, load, positioning accuracy and the like, are required to reach higher standards as much as possible, so that the cooperative mechanical arm can participate in the work in more fields. The cooperative mechanical arm generally comprises a plurality of working shafts, and coordinated operation of a plurality of degrees of freedom is realized through mutual cooperation, so that the purpose of accurately controlling the direction is achieved, and finally, operation command action is realized.

Small mechanical arms which can coexist with people and do not need to specially divide a safe working area in the market are roughly divided into two types.

The first type is a small robotic arm based on a stepper motor or steering engine. Because the mechanical arm uses the stepping motor or the steering engine, the control principle is open-loop control, namely if the motor does not reach the specified target due to interference, load and the like, the mechanical arm cannot know the feedback, and therefore the adjustment cannot be carried out to eliminate errors. This completely limits the motion performance of such a robotic arm, i.e. only moving tasks from one point to another can be achieved, and a complete trajectory cannot be followed exactly from three indices of position, velocity, and acceleration. In addition, with additional load, the mechanical arm may have a large steady-state error due to only open-loop control. In addition, due to the adoption of open-loop control, the mechanical arm cannot realize the function of collision detection, so that the mechanical arm can safely coexist with people, the power can be reduced, the size can be reduced to ensure that even if people collide, the mechanical arm cannot cause too much damage, and the mechanical arm is mostly used in the fields of visual inspection of light loads, electronic element sorting, children intelligence development and the like and cannot bear wide industrial and non-industrial automation tasks.

The second type is a mechanical arm called a "cooperative robot". The mechanical arm has high precision and good motion performance, and is more and more applied to various production lines due to coexistence with people. At present, the cooperative mechanical arms on the market all adopt a torque motor or a disc motor. The motor has the advantages of large torque and capability of directly driving the load without any transmission device such as gears, belts and the like. However, the most serious disadvantage of this type of motor is high cost, and the cost and the torque magnitude are not linear. The cooperating robot arms based on torque motors are therefore constrained in size to a range for cost reasons, since once outside this range, it is necessary to carry a much more costly torque motor. Furthermore, this type of design without a transmission system has the significant disadvantage of poor ductility. This is because each motor must be mounted in the joint itself, since there is no drive train, which results in the lower motors bearing the mass of all the higher motors. For example, the low-level shaft motor must bear not only the end load but also the dead weight of the high-level shaft motor. This makes it difficult to increase the maximum load of the robot arm, because the power and the weight of each motor are increased to increase the maximum load, but this results in an increase in the weight of the high motor borne by each low motor, and as a result, a large part of the increased power is still used to bear the weight of the motor.

The conventional AGV navigation technology mainly comprises a navigation scheme utilizing technologies such as magnetic guide rails, laser detection or inertia, and the like, the scheme utilizing the magnetic guide rail technology has extremely high requirements on fields, and the later change and adjustment are extremely difficult; the navigation scheme using laser detection and inertia technology relies on extremely high equipment cost.

Therefore, in order to solve some of the above technical problems, a more reasonable technical solution needs to be provided in the art.

Disclosure of Invention

The invention provides a self-adaptive AGV robot and a self-adaptive navigation method, and aims to fix a cooperative mechanical arm on a vehicle body, drive the cooperative mechanical arm to move through the vehicle body, and realize that the cooperative mechanical arm can reach a designated area in time to execute a task. The vehicle body can actively walk in the inspection area through a self-adaptive navigation method, identify road conditions in the front road, analyze and distinguish obstacles in the front road, and realize active detour obstacle avoidance.

In order to achieve the above effects, the technical scheme adopted by the invention is as follows:

a self-adaptive AGV robot comprises a vehicle body, a navigation device arranged on the vehicle body and an execution device arranged on the vehicle body.

Specifically, the navigation device comprises a processor, a detection radar, a detection camera, a first filter and a second filter, wherein the detection radar, the detection camera, the first filter and the second filter are respectively connected with the processor.

The executing device comprises a base, a mechanical arm with six degrees of freedom arranged on the base, and an executing steering engine arranged at the tail end of the mechanical arm, wherein the mechanical arm comprises a first driving box, a four-bar mechanism, a second driving box, a sleeve shaft machine arm, a tail end transmission head and a tail end executing head which are sequentially connected. Specifically, a first rotating shaft rotating relative to the base is arranged on the base, the first driving box is fixedly connected with the upper end of the first rotating shaft, a worm and gear driving assembly is arranged on the base and connected with the lower end of the first rotating shaft and synchronously driven; a second rotating shaft and a third rotating shaft are arranged in the first driving box and are respectively driven by a second motor and a third motor, and the four-bar linkage mechanism is enclosed into a parallelogram and is in matched transmission with the second rotating shaft and the third rotating shaft; the second driving box is fixed at the upper end of the four-bar linkage, the second driving box comprises a second box body, two direct-current brush motors are arranged on the rear surface of the second box body, a speed reduction transmission mechanism connected with the two direct-current brush motors is arranged in the second box body, the sleeve shaft mechanical arm comprises an inner layer output shaft and an outer layer output shaft which are connected with the speed reduction transmission mechanism in a transmission mode respectively, the outer layer output shaft is connected with a tail end transmission head and drives the tail end transmission head to rotate coaxially, the inner layer output shaft extends into the tail end transmission head and is connected with the tail end execution head through a primary gear pair in a transmission mode, and the tail end execution head and the tail end transmission head rotate relatively.

The invention takes a vehicle body as a walking system of the robot, carries an actuating mechanism to advance through the vehicle body, and realizes self-adaptive navigation by utilizing a navigation system on the vehicle body; the actuating mechanism is used as a power mechanism of the whole mechanical arm through the worm gear and worm driving assembly, the first driving box and the second driving box, the four-bar mechanism, the shaft sleeve mechanical arm and the tail end transmission head are used as transmission mechanisms, and the tail end actuating head is connected with the tail end actuator to realize final actuating action.

Wherein, about the automobile body part, the frame include the bed frame, the bed frame includes the outer fringe strip of rectangle and sets up net in the check of square grid in the outer fringe strip, well net is including intensive layer and sparse layer, sparse layer laminating is in the lower part on intensive layer, the same and half of outer fringe strip height that is of thickness on sparse layer and intensive layer.

The differential driving device is arranged in the center of the frame along the width direction and comprises a main control board and two square motor bases which are oppositely arranged, the main control board can be arranged on the frame and can also be arranged in other controllers carried on the frame, and when the main control board is arranged in the other controllers, integrated control and management are facilitated; the motor base is internally provided with a motor electrically connected with the main control board, a motor rotating shaft is connected with a speed reducer, the speed reducer is connected to a driving wheel, the two motors respectively drive one driving wheel, when the motion states of the two motors are synchronous, the AGV can advance or retreat, and when the motion states of the two motors are asynchronous with each other, the AGV can steer; the middle parts of the two wide edges of the frame are provided with a front guide assembly and a rear guide assembly, the front guide assembly and the rear guide assembly respectively comprise a front wheel seat and a rear wheel seat, the front wheel seat is provided with a front guide wheel, and the rear wheel seat is provided with a rear guide wheel.

Further, need the installation on the frame to bear the weight of the navigation head and the cooperation arm of AGV, and the overall arrangement of each part on the frame can influence the function of AGV, for convenient free setting each part, carries out reasonable the laying to its position, optimizes above-mentioned scheme, all be provided with vertical ascending connection dop on motor cabinet, front wheel seat and the rear wheel seat, connect the dop and include the first dop of card income sparse layer and the second dop of card income intensive layer, the second dop is located the top of first dop, and the top of second dop is provided with the screw.

Still further, the mesh size that sparse layer and intensive layer correspond is different, and the mesh size on sparse layer is greater than the mesh size on intensive layer, increases the stability that the fixed point of connection can improve the installation, consequently optimizes above-mentioned technical scheme, first dop top be equipped with two at least second dops.

Furthermore, the motor base is large in size, and a driving force part is installed, so that the motor base is easy to loosen, and more points are required to be stressed for stabilization; the front wheel seat and the rear wheel seat are small in structural size, only driven parts are mounted, and the stability is high; therefore, the technical scheme is optimized, the number of the connecting chucks on the motor base is more than two, the connecting chucks are both positioned on the side surface of the motor base, and the connecting chucks on the front wheel base and the rear wheel base are respectively positioned on the upper end surfaces of the front wheel base and the rear wheel base.

Furthermore, the evacuation layer and the dense layer respectively comprise transverse lattice bars and longitudinal lattice bars, the transverse lattice bars and the longitudinal lattice bars are mutually vertical, and the thickness of the transverse lattice bars is the same as that of the longitudinal lattice bars.

Still further, the transverse lattice bars are parallel to the long edge direction of the outer edge bars, and the distance between the adjacent transverse lattice bars of the dense layer is equal to the thickness of the transverse lattice bars.

The vehicle body is structurally explained, when the differential steering device is applied specifically, the two motors of the differential driving device are controlled by the main control board to rotate respectively, and the rotation parameters of the two driving wheels corresponding to the motors are also different, so that differential steering can be realized; when the rotation parameters of the two driving wheels are the same, the forward and backward movement can be realized.

With respect to the cooperating arm portions, the base of the cooperating arms is connectively secured to the upper surface of the vehicle body; the worm and gear driving assembly comprises a first motor, a worm is connected to the first motor, the worm is in matched transmission with a worm gear arranged on a first rotating shaft, and the first motor drives the first rotating shaft to rotate through the worm and gear after running, so that the rotation of the mechanical arm in the horizontal direction is realized; the second rotating shaft and the third rotating shaft in the first driving box realize driving the four-bar mechanism to run, and realize the circumferential motion and pitching motion of the second driving box in the longitudinal direction; the direct current brush motor on the second driving box controls the inner output shaft and the outer output shaft of the sleeve shaft machine arm to rotate through the speed reduction transmission mechanism, the rotation of the outer output shaft drives the tail end transmission head and the tail end execution head to coaxially rotate, and the rotation of the inner output shaft can drive the tail end execution head to rotate perpendicular to the tail end transmission head so as to realize the angle adjustment in the other direction; the execution steering engine at the tail end is used as a power device for driving the actuator to move, and can be independently operated to execute actions.

Further, optimize to above-mentioned technical scheme, four-bar linkage include first driving lever, second driving lever, first driven lever and second driven lever, first driving lever is connected perpendicularly and rotates along with the axle with the second pivot, second driving lever is connected perpendicularly and rotates along with the axle with the third pivot, first driven lever is articulated with first driving lever and is fixed to the second box, second driven lever one end is articulated with the second driving lever, the other end is articulated with first driven lever.

Furthermore, the weight of the mechanical arm is reasonably controlled, the load of the motor can be reduced, the effective power of the motor and the overall mechanical efficiency can be conveniently improved, and therefore appropriate weight reduction setting is made on the mechanical arm on the premise of not reducing the overall strength. As a preferred scheme, the two driving rods and the two driven rods are both sheet-shaped bar-shaped rods, wherein the first driving rod mainly bears the weight and is used for adjusting the movement of the first driven rod on the longitudinal circumferential surface, the thickness of the first driving rod is larger than that of the other three rods, and the first driving rod is also provided with a weight-reducing groove and/or a weight-reducing hole, so that the burden of the first motor and the burden of the second motor are reduced; the second driving rod and the second driven rod are mainly adjusted and used for adjusting the pitching angle of the first driven rod, so that the second driving rod and the second driven rod are relatively thin strip-shaped rods. The length of first drive rod and second driven rod is the same, and the length of second drive rod is the same with first driven rod, forms parallelogram structure from this.

Furthermore, the technical scheme is optimized, the second motor and the third motor are generally direct current brush motors, the second motor and the third motor are oppositely arranged in the first transmission box, and the second rotating shaft and the third rotating shaft are respectively connected with a two-stage gear pair and are connected with the second motor and the third motor for transmission. The axes of the output gears of the two-stage gear pairs are overlapped, one output gear is coaxially connected with the second rotating shaft, and the other output gear is coaxially connected with the third rotating shaft.

Still further, because the second motor and the third motor adopt direct current brush motors, the working torque thereof is limited, and in order to meet the requirement of large torque output, the transmission structure needs to be improved under the condition of not changing the motors, so the technical scheme is optimized, the two-stage gear pair is a straight gear pair, and the transmission ratio is more than or equal to three. The straight gear pair does not generate axial force, the transmission stability is good, and the service life is long; the transmission ratio is larger than or equal to three, the torque of the motor is amplified by at least three times, and the torque acted on the second rotating shaft and the third rotating shaft through the gear pair can meet the working output requirement of the first driving box.

Furthermore, the speed reduction transmission mechanism is arranged in the second driving box and transmits the power of the two direct current brush motors to the sleeve shaft mechanical arm, and the inner output shaft and the outer output shaft of the sleeve shaft mechanical arm realize coaxial relative rotation; the technical scheme is described in detail, the speed reduction transmission mechanism comprises two groups of transmission gear sets, each transmission gear set at least comprises a driving wheel and a driven wheel, a fourth rotating shaft and a fifth rotating shaft are arranged in the second box body, the two driving wheels are respectively connected with the two direct current brush motors, and the two driven wheels are respectively arranged on the fourth rotating shaft and the fifth rotating shaft; the fourth rotating shaft and the inner output shaft rotate coaxially, and the fifth rotating shaft and the outer output shaft rotate coaxially. Therefore, one direct current brush motor can control the outer output shaft to operate, and the other direct current brush motor can control the inner output shaft to operate.

Still further, when the arm was in the execution action, the torque that different pivot departments correspond was different, in order to measure the torque of pivot department to the further correction setting of being convenient for, optimize above-mentioned technical scheme, first pivot, second pivot, third pivot, fourth pivot and fifth pivot on all be provided with torque sensor. The torque sensor generally adopts a piezoelectric sensor, and an electric signal is generated through pressure contact, so that the torque at the position is calculated.

Furthermore, the length of the sleeve shaft machine arm determines the working radius of the whole mechanical arm to a certain extent, so that the length requirements of the sleeve shaft machine arm are different on different occasions, the switching is convenient, the fitting degree between parts is improved, the efficiency is prevented from being reduced, the technical scheme is optimized, the outer-layer output shaft comprises a head section, an extension section and a tail section, the head section is connected with the speed reduction transmission mechanism, two ends of the extension section are respectively connected with the head section and the tail section, and the tail section is connected with the tail end transmission head; the head section, the extension section and the tail section rotate synchronously.

Furthermore, the technical scheme is optimized to change the movement direction of the end execution head, the primary gear pair comprises a first driving bevel gear and a first driven bevel gear, the first driving bevel gear is coaxially arranged on the inner layer output shaft, the first driven bevel gear is arranged on the end execution head, the conicity of the first driving bevel gear and the conicity of the first driven bevel gear are both 45 degrees, and therefore 90-degree steering transmission is achieved through rotation of the inner layer output shaft.

Still further, optimize above-mentioned technical scheme, terminal transmission head include with outer output shaft connection's fixed part, with the main part of fixed part connection, the main part is inside hollow, and be provided with the shaft hole that is used for connecting the end and carries out the head on the lateral wall of main part. The fixing part comprises a sleeve and a flat plate, the sleeve is sleeved on the outer-layer output shaft, and the flat plate is vertically fixed with the sleeve; the main body portion is fixedly connected to the flat plate.

And the technical scheme is optimized, the tail end execution head comprises a connecting plate and an execution body, the connecting plate is rotatably connected with the tail end transmission head, the execution body is fixedly connected with the connecting plate, an execution cavity is arranged on the execution body, a through hole is formed in the side wall of the execution cavity, the execution steering engine is fixed in the execution cavity, and a rotating shaft of the execution steering engine extends out of the through hole.

The above-mentioned content explains the composition of the mechanical arm in detail from the structure, the invention has also disclosed the method to carry on the self-adaptation navigation to the above-mentioned robot, mainly include seek way step and processing step after colliding in the operation:

path finding step:

s01: scene recognition and data acquisition are carried out outside the range of 0.5 meter through a depth camera to form point cloud data; filtering the point cloud according to the normal vector direction, and removing all points with the normal vector direction within 10 degrees from the Z-axis direction; the remaining points are sent to an obstacle map of the robot's travel. Therefore, all horizontal surfaces can be filtered, and only real obstacle points are reserved; if the front is a gentle slope, the point of the slope will still be filtered out and not be considered as an obstacle point because the slope normal vector is still within 10 degrees of the Z-axis direction.

S02: scanning and detecting within the range of 0.5 m by using a laser radar to obtain laser scanning points, filtering and screening the laser scanning points, and adding the laser scanning points corresponding to the obstacles to an obstacle map in a noise point mode. The method is specifically divided into the following steps:

1) sequencing all laser scanning points according to polar coordinates;

2) sequentially considering each point according to the polar coordinate sequence;

3) if the linear distance between the current point P and any point Q in M points with similar polar coordinates is smaller than a threshold value, and the included angle between a connecting line from the laser origin O to the P and a connecting line from the P to the Q is larger than a threshold value min and smaller than a threshold value max, marking the Q as an effective neighbor of the P, otherwise, marking as an ineffective neighbor;

4) all points with a valid neighbor number less than or equal to 2 are discarded.

In step S02, the complexity of the algorithm for realizing the laser scanning points is o (nlogn) + o (n) ═ o (nlogn), so that almost no extra calculation load is imposed on the algorithm for the navigation path, and the frame rate of the laser information processing is not reduced.

S03: and according to the coordinate positioning of the obstacle map, the processor designates a new traveling path, and the designated robot advances according to the new traveling path.

The conventional method for controlling the driving motor of the AGV is PI speed loop control, that is, the rotating speed is accurately controlled by Proportional (proportionality) control and Integral (Integral) control and by actually measuring the feedback information of the rotating speed of the motor. This method is based on linear model analysis, however, the actual motor is not purely linear, and especially at low rotational speeds the motor exhibits a very strong nonlinearity due to unmodeled coulomb friction and nonlinear viscous friction. The most typical example is the motor dead zone, i.e. the PWM duty cycle is below a certain value, which does not enable the motor to run. When the ideal proportional-integral speed loop control is used for a nonlinear motor in AGV intelligent platform control, the following problems are solved:

1) the motor runs unsmoothly during low-speed movement, and is easy to start and stop frequently. This is because the PWM value of the speed loop output often cannot break through the dead band.

2) The motor output speed tends to swing between overshoot and non-overshoot at low speeds. This is because the speed loop natural frequency w to damping ratio d specified in the linear analysis is chosen according to the speed at which the AGV is operating normally. However, the low-speed nonlinearity directly causes a large decrease in the damping ratio, and hence the oscillation is likely to occur.

3) When the AGV encounters a complex obstacle, the navigation module usually enables the AGV to run at a low speed, and at this time, if the AGV collides with an undiscovered obstacle due to a sensor blind area, the variation of a method for judging the collision through the current change of the motor is insensitive or even fails due to the low damping ratio caused by nonlinearity. This is because the proportional and integral gains are actually very low at low speed, and the response of the speed loop is very slow when collision occurs, so that the output PWM command has a significant time delay to increase greatly, which finally shows that the current change is slow.

For this reason, a post-collision processing procedure is proposed for the navigation control of the robot.

The processing step is a collision detection control method based on speed loop adaptive gain adjustment, and comprises the following steps:

s04: the gain parameter is dynamically adjusted by directly adjusting the rotating speed of the motor, so that the problem of nonlinearity of the motor in low-speed operation is solved, and the change of the current value output by the motor at low speed tends to be linear.

S05: and filtering the motor current by using a first-order exponential filter to obtain the instantaneous average current I _ avg.

S06: and (3) judging that the AGV collides at any moment when the real-time current | I-I _ avg | of the motor > t is greater, and stopping the movement of the AGV immediately at the moment. And the position of the point of impact relative to the AGV is evaluated by the direction of the different motor current changes.

S07: standing for a waiting time T, and then rotating at a low speed of 360 degrees; if the current value returns to normal, judging that the current value meets the movement obstacle, and if the current value does not meet the movement obstacle, the current value leaves the current value, and returning to normal running; if the current value is increased during rotation, the obstacle is judged to still exist, the obstacle is confirmed to be a static obstacle, and the obstacle is added into the obstacle map.

S08: the processor designates the robot to back up at a low speed, and re-executes steps S02 and S03.

Compared with the prior art, the invention has the beneficial effects that:

1. the invention has simple structure, eliminates the arrangement of a large motor, and ensures that the machine body has small dead weight and low cost.

2. The direct current brush motor of the second driving box is arranged at the rear part, and the self weight of the motor does not become the burden of other motors, so that the mechanical arm can realize longer arm extension and larger load compared with the similar cooperative mechanical arm.

3. The invention makes each part relatively independent, and no matter the motor or the gear pair, the speed reducing transmission mechanism or the sleeve shaft machine arm, the arm extension or the load can be further lifted through the change of the lifting power or the transmission ratio, and the production cost is hardly improved, thereby having good expandability.

4. The laser radar and the depth camera are combined, so that the overlapping coverage of different sight distance angles is realized, and the complementation of the laser radar and the depth camera is realized; and by adopting a laser filtering method with O (NLogN) complexity, noise in the laser data is effectively removed, and the interference on an AGV navigation system is avoided. Through the analysis of the motor linear model and the actual nonlinearity, the speed loop gain is dynamically adjusted according to the actual speed feedback, and the smooth and sensitive response of the full-speed section of the motor is realized; after the robot collides, the collision itself is converted into favorable information, and collision points are added into the obstacle map, so that richer reference information is provided for later navigation. .

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is an exploded view of the vehicle body and actuator of the present invention.

Fig. 2 is an overall mechanism schematic diagram of the vehicle body.

Fig. 3 is a schematic view of the installation position of the navigation device on the vehicle body.

Fig. 4 is a schematic view of the overall structure of the actuator from one perspective.

Fig. 5 is a schematic view of the overall structure of the actuator from another perspective.

Fig. 6 is a schematic structural view of the base.

FIG. 7 is a schematic structural diagram of a worm gear and worm driving mechanism

Fig. 8 is a schematic diagram and a partial enlarged schematic diagram of an internal transmission structure of the first driving box.

Fig. 9 is a schematic structural view of the four-bar linkage.

Fig. 10 is a schematic view of the internal transmission structure of the second drive case.

Fig. 11 is a schematic view of the overall structure of the quill arm.

Fig. 12 is an exploded view of the quill arm.

Fig. 13 is a schematic view of the overall structure at the end drive head.

Fig. 14 is a schematic view of the internal drive structure of the end drive head.

Fig. 15 is a schematic view of the transmission structure of the second driving box, the sleeve shaft machine arm and the tail end transmission head.

FIG. 16 is a conventional AGV drive motor control flow diagram.

FIG. 17 is a flow diagram of an improved AGV drive motor control.

In the figure: 1-a base; 101-a first motor, 102-a worm; 103-a turbine; 104-a first shaft; 2-a first drive box; 201-a second motor; 202-a third motor; 203-a second rotating shaft; 204-a third rotating shaft; 3-a four-bar linkage; 301-a first active lever; 302-a first driven lever; 303-a second active lever; 304-a second driven lever; 305-weight reduction slots; 306-lightening holes; 4-a second drive box; 401-direct current brush motor; 402-a fifth rotating shaft; 403-a fourth shaft; 5-sleeve shaft machine arm; 501-outer output shaft; 501 a-a head section; 501 b-an extension; 501 c-tail section; 502-inner output shaft; 6-end drive head; 601-a stationary part; 602-a body portion; 7-an end effector head; 8, executing a steering engine; 9-a torque sensor; 10-a first drive bevel gear; 11-a first driven bevel gear; 12 a vehicle body; 13-a base frame; 1301-an outer edge strip; 1302-dense layer; 1303-evacuation layer; 14-a motor base; 15-driving wheels; 16-front wheel seat; 16' -rear wheel seat; 17-a front guide wheel; 17' -a rear guide wheel; 18-a first chuck; 19-a second chuck; 20-a detection camera; 21-detecting radar.

Detailed Description

The invention is further explained below with reference to the drawings and the specific embodiments.

Example 1:

as shown in fig. 1, 2, 3, 4, and 5, the present embodiment discloses an adaptive AGV robot including a vehicle body, a navigation device provided on the vehicle body, and an execution device provided on the vehicle body.

Specifically, the navigation device comprises a processor, a detection radar 21, a detection camera 20, a first filter and a second filter, wherein the detection radar, the detection camera, the first filter and the second filter are respectively connected with the processor.

In this embodiment, the detection radar is a laser detection radar, and the first filter is a laser radar filter; the detection camera is a depth camera, and the second filter is a depth camera point cloud filter.

The laser radar is fixedly installed according to a certain downward inclination angle, so that the laser radar can detect obstacles in a certain height range; the installation position of the depth camera is towards the right front of the robot, and the depth camera can also be raised upwards by a certain angle, so that the angle of the depth camera is more suitable for observing the target above the front, and more complex functions such as target following are realized. Although the respective visual angles of the laser radar and the depth camera are limited, the combination can cover a sufficient range, and obstacles can be effectively found.

For a navigation device, if only a laser radar is used for navigation, a plurality of radars are often required to perform full-coverage scanning on obstacles with different angles and different heights, so that the cost and the power consumption are seriously increased. The barrier in bigger height range can be seen to the degree of depth camera, can compensate laser radar's not enough, but its self has the stadia narrow, and dead zone scheduling problem just in the place ahead. Therefore, the embodiment combines the advantages of the two devices and is matched with a motor gain self-adaptive collision detection processing method to realize low-cost and reliable navigation.

The executing device comprises a base 1, a mechanical arm with six degrees of freedom arranged on the base, and an executing steering engine 8 arranged at the tail end of the mechanical arm, wherein the mechanical arm comprises a first driving box 2, a four-bar mechanism 3, a second driving box 4, a sleeve shaft mechanical arm 5, a tail end transmission head 6 and a tail end executing head 7 which are sequentially connected. Specifically, as shown in fig. 6, the base is provided with a first rotating shaft 104 which rotates relative to the base, as shown in fig. 8, the first driving box is fixedly connected with the upper end of the first rotating shaft, the base is provided with a worm and gear driving assembly, and the worm and gear driving assembly is connected with the lower end of the first rotating shaft and synchronously drives the first rotating shaft; a second rotating shaft 203 and a third rotating shaft 204 are arranged in the first driving box and are respectively driven by a second motor 201 and a third motor 202, and the four-bar linkage mechanism is enclosed into a parallelogram and is in matched transmission with the second rotating shaft and the third rotating shaft; as shown in fig. 10, the second driving box is fixed at the upper end of the four-bar linkage, the second driving box includes a second box body, the rear surface of the second box body is provided with two direct current brush motors 401, a speed reduction transmission mechanism connected with the two direct current brush motors is arranged in the second box body, as shown in fig. 11, 12 and 13, the sleeve arm includes an inner output shaft 502 and an outer output shaft 501, which are respectively connected with the speed reduction transmission mechanism for transmission, the outer output shaft is connected with the terminal transmission head and drives the terminal transmission head to coaxially rotate, the inner output shaft extends into the terminal transmission head and is connected with the terminal execution head through a primary gear pair for transmission, so that the terminal execution head and the terminal transmission head relatively rotate, and the maximum torque of the execution steering engine is 50kg · cm. Two direct currents on the second box have brush motor and be 40W's brush direct current motor, and the motor self has 51: 1 speed ratio planetary reduction box.

The invention takes a vehicle body as a walking system of the robot, carries an actuating mechanism to advance through the vehicle body, and realizes self-adaptive navigation by utilizing a navigation system on the vehicle body; the actuating mechanism is used as a power mechanism of the whole mechanical arm through the worm and gear driving assembly, the first driving box and the second driving box, the four-bar mechanism, the shaft sleeve mechanical arm and the tail end transmission head are used as transmission mechanisms, and the tail end actuating head is connected with the tail end actuator to realize final actuating action. The cooperative mechanical arm can be widely applied to various automatic production procedures, such as stacking, sorting, visual inspection and the like. In addition, the device can be co-deployed with people in a working area and is closely cooperated with people so as to realize automatic application outside the industrial field, such as coffee brewing, cooking, health care and the like.

The robot is PLA (polylactic acid) material that full 3D printed, has light in weight, advantage with low costs. The structural design of the whole robot considers that the whole mechanical arm can be printed by 3D printing, 3D parts are reinforced at certain parts with larger stress, and the thickness and other parameters of materials are reduced as much as possible at certain parts capable of reducing weight.

Wherein, regarding the vehicle body part, the vehicle body comprises a frame and a drive system arranged below the frame.

In this embodiment, the frame includes the pedestal 13, and the pedestal includes rectangular outer fringe strip 1301 and sets up the grid in the square grid in the outer fringe strip, well net is including dense layer 1302 and sparse layer 1303, the sparse layer laminating is in the lower part of dense layer, and the thickness of sparse layer and dense layer is the same and is half of outer fringe strip height.

The outer edge strips and the middle net are both made of polyurethane materials and are integrally formed.

A differential driving device is arranged at the center of the frame along the direction of the wide edge, and comprises a main control board and two square motor bases 14 which are oppositely arranged; in this embodiment, the main control board may be disposed on the frame, or may be disposed in another controller mounted on the frame, so that when the main control board is disposed in another controller, integrated control and management are facilitated; the motor base is internally provided with a motor electrically connected with the main control board, a rotating shaft of the motor is connected with a speed reducer, the speed reducer is connected to a driving wheel, the two motors respectively drive one driving wheel 15, when the motion states of the two motors are synchronous, the AGV can advance or retreat, and when the motion states of the two motors are asynchronous with each other, the AGV can steer; the middle parts of the two wide edges of the frame are provided with a front guide assembly and a rear guide assembly, the front guide assembly and the rear guide assembly respectively comprise a front wheel seat 16 and a rear wheel seat 16 ', a front guide wheel 17 is arranged on the front wheel seat, and a rear guide wheel 17' is arranged on the rear wheel seat.

Need install navigation head, the cooperation arm that bears AGV on the frame, and the overall arrangement of each part on the frame can influence AGV's function, in order to conveniently freely set up each part, carries out reasonable the laying to its position, and this embodiment is optimized above-mentioned scheme, all be provided with vertical ascending connection dop on motor cabinet, front wheel seat and the rear wheel seat, connect the dop and include the first dop 18 of card income sparse layer and the second dop 19 of card income intensive layer, the second dop is located the top of first dop, and the top of second dop is provided with screw 8. The first clamping head and the second clamping head are both square, and the size of the second clamping head is the same as the mesh size of the dense layer.

The mesh size that sparse layer and intensive layer correspond is different, and the mesh size on sparse layer is greater than the mesh size on intensive layer, increases and connects the stability that the fixed point can improve the installation, consequently optimizes above-mentioned technical scheme, first dop top be equipped with two second dops or three dop.

The motor base is larger than the front wheel base and the rear wheel base in size, and a driving force part is installed, so that the motor base is easy to loosen, and more points need to be arranged for stress stabilization; the front wheel seat and the rear wheel seat are relatively small in structural size, only driven parts need to be installed, and the stability is high; therefore, the technical scheme is optimized by the embodiment, the number of the connecting chucks on the motor base is larger than two, the connecting chucks are all positioned on the side surface of the motor base, and the connecting chucks on the front wheel base and the rear wheel base are respectively positioned on the upper end surface of the front wheel base and the upper end surface of the rear wheel base.

In this embodiment, in order to improve stability, reduce the installation degree of difficulty, improve the convenience of installation, motor cabinet, front wheel seat and rear wheel seat with locate above that connection dop integrated into one piece.

The middle net is arranged into a dense layer and an evacuation layer, wherein the dense layer is used for being connected and fixed, the stability of the connecting parts is ensured, the mesh size of the evacuation layer is larger than that of the dense layer, materials can be reduced, the dead weight of the frame is reduced, the energy consumption is reduced, and the endurance is increased. In this embodiment, the long side direction of one mesh of the evacuation layer corresponds to two meshes arranged according to the long side of the dense layer, and the short side direction of one mesh of the evacuation layer corresponds to three meshes arranged according to the short side of the dense layer.

The evacuation layer and the dense layer respectively comprise transverse lattice bars and longitudinal lattice bars, the transverse lattice bars are perpendicular to the longitudinal lattice bars, and the thickness of the transverse lattice bars is the same as that of the longitudinal lattice bars.

In this embodiment, the transverse lattice bars are parallel to the long side direction of the outer edge bars, and the distance between adjacent transverse lattice bars of the dense layer is equal to the thickness of the transverse lattice bars.

In addition, regarding the cooperative arm portion, a base of the cooperative arm is fixedly attached to an upper surface of the vehicle body; as shown in fig. 7, the worm and gear driving assembly includes a first motor 101, the first motor is connected with a worm 102, the worm is in transmission with a worm gear 103 arranged on a first rotating shaft in a matching manner, and the first motor drives the first rotating shaft to rotate through the worm and gear after operation, so that the rotation of the mechanical arm in the horizontal direction is realized; the second rotating shaft and the third rotating shaft in the first driving box realize driving the four-bar mechanism to run, and realize the circumferential motion and pitching motion of the second driving box in the longitudinal direction; the direct current brush motor on the second driving box controls the inner output shaft and the outer output shaft of the sleeve shaft machine arm to rotate through the speed reduction transmission mechanism, the rotation of the outer output shaft drives the tail end transmission head and the tail end execution head to coaxially rotate, and the rotation of the inner output shaft can drive the tail end execution head to rotate perpendicular to the tail end transmission head so as to realize the angle adjustment in the other direction; the execution steering engine at the tail end is used as a power device for driving the actuator to move, and can be independently operated to execute actions.

First motor, second motor and third motor are 90W's brush direct current motor, and the motor itself has 77: 1 speed ratio planetary reduction box.

As shown in fig. 9, the technical solution is optimized, the four-bar linkage includes a first driving rod 301, a second driving rod 303, a first driven rod 302 and a second driven rod 304, the first driving rod is vertically connected with the second rotating shaft and rotates along with the shaft, the second driving rod is vertically connected with the third rotating shaft and rotates along with the shaft, the first driven rod is hinged to the first driving rod and fixed to the second box, one end of the second driven rod is hinged to the second driving rod, and the other end of the second driven rod is hinged to the first driven rod.

The weight of the mechanical arm is reasonably controlled, the burden of the motor can be reduced, the effective power of the motor and the overall mechanical efficiency are convenient to improve, and therefore appropriate weight reduction setting is made on the mechanical arm on the premise that the overall strength is not reduced. Preferably, the two driving rods and the two driven rods are sheet-shaped strip-shaped rods, wherein the first driving rod is mainly loaded, has a length of 50cm and is used for adjusting the movement of the first driven rod on the longitudinal circumferential surface, the thickness of the first driving rod is larger than that of the other three rods, and the first driving rod is further provided with a weight reduction groove 305 and/or a weight reduction hole 306, so that the loads of the first motor and the second motor are reduced; the second driving rod and the second driven rod are mainly adjusted and used for adjusting the pitching angle of the first driven rod, so that the second driving rod and the second driven rod are relatively thin strip-shaped rods. The length of first drive rod and second driven rod is the same, and the length of second drive rod is the same with first driven rod, forms parallelogram structure from this.

As shown in fig. 8, the above technical solution is optimized, and the second rotating shaft and the third rotating shaft are respectively connected to a two-stage gear pair and are in transmission connection with the second motor and the third motor. The axes of the output gears of the two-stage gear pairs are overlapped, one output gear is coaxially connected with the second rotating shaft, and the other output gear is coaxially connected with the third rotating shaft.

Because the second motor and the third motor adopt direct current brush motors, the working torque of the second motor and the third motor is limited, and in order to meet the requirement of large torque output, the transmission structure needs to be improved under the condition of not changing the motors, so the technical scheme is optimized, the two-stage gear pair is a straight gear pair, and the transmission ratio is equal to three. The straight gear pair does not generate axial force, the transmission stability is good, and the service life is long; the transmission ratio is equal to three, the torque of the motor is amplified by three times, and the torque applied to the second rotating shaft and the third rotating shaft through the gear pair can meet the working output requirement of the first driving box.

As shown in fig. 10, the speed reduction transmission mechanism is arranged in the second driving box, and transmits the power of the two direct current brush motors to the sleeve shaft mechanical arm, and the inner layer output shaft and the outer layer output shaft of the sleeve shaft mechanical arm realize coaxial relative rotation; the technical scheme is explained in detail, the speed reduction transmission mechanism comprises two groups of transmission gear sets, each transmission gear set comprises a driving wheel and a driven wheel, a fourth rotating shaft 403 and a fifth rotating shaft 402 are arranged in the second box body, the two driving wheels are respectively connected with the two direct current brush motors, and the two driven wheels are respectively arranged on the fourth rotating shaft and the fifth rotating shaft; the fourth rotating shaft and the inner output shaft rotate coaxially, and the fifth rotating shaft and the outer output shaft rotate coaxially. Therefore, one direct current brush motor can control the outer output shaft to operate, and the other direct current brush motor can control the inner output shaft to operate.

When the mechanical arm executes actions, the corresponding torques at different rotating shafts are different, the technical scheme is optimized in order to measure the torques at the rotating shafts and facilitate further correction setting, and the torque sensors 9 are arranged on the first rotating shaft, the second rotating shaft, the third rotating shaft, the fourth rotating shaft and the fifth rotating shaft. The torque sensor adopts a piezoelectric sensor, and generates an electric signal through pressure contact, so that the torque at the position is calculated.

As shown in fig. 12, the length of the sleeve shaft arm determines the working radius of the whole mechanical arm to a certain extent, so that in different occasions, the length requirements of the sleeve shaft arm are different, in order to facilitate switching, improve the fit degree between parts, and avoid reducing efficiency, the technical scheme is optimized, the outer layer output shaft comprises a head section 501a, an extension section 501b and a tail section 501c, the head section is connected with a speed reduction transmission mechanism, two ends of the extension section are respectively connected with the head section and the tail section, and the tail section is connected with a tail end transmission head; the head section, the extension section and the tail section rotate synchronously.

As shown in fig. 13, 14 and 15, the above technical solutions are optimized to change the moving direction of the end effector, the primary gear pair includes a first driving bevel gear 10 coaxially disposed on the inner output shaft and a first driven bevel gear 11 disposed on the end effector, and the tapers of the first driving bevel gear and the first driven bevel gear are both 45 °, so that the rotation of the inner output shaft is realized by 90 ° steering transmission.

Optimize above-mentioned technical scheme, terminal transmission head include with outer output shaft connection's fixed part 601, with the main part 602 that the fixed part is connected, the main part is inside hollow, and be provided with the shaft hole that is used for connecting the end and carries out the head on the lateral wall of main part. The fixing part comprises a sleeve and a flat plate, the sleeve is sleeved on the outer-layer output shaft, and the flat plate is vertically fixed with the sleeve; the main body portion is fixedly connected to the flat plate.

The technical scheme is optimized, the tail end execution head comprises a connecting plate and an execution body, the connecting plate is connected with the tail end transmission head in a rotating mode, the execution body is fixedly connected with the connecting plate, an execution cavity is arranged on the execution body, a through hole is formed in the side wall of the execution cavity, the execution steering engine is fixed in the execution cavity, and a rotating shaft of the execution steering engine extends out of the through hole.

Example 2:

the embodiment discloses a method for self-adaptive navigation of the robot disclosed in the embodiment 1, which mainly comprises a path searching step in operation and a processing step after collision:

path finding step:

s01: scene recognition and data acquisition are carried out outside the range of 0.5 meter through a depth camera to form point cloud data; filtering the point cloud according to the normal vector direction, and removing all points with the normal vector direction within 10 degrees from the Z-axis direction; the remaining points are sent to an obstacle map of the robot's travel. Therefore, all horizontal surfaces can be filtered out, and only real obstacle points are reserved; if the front is a gentle slope, the point of the slope will still be filtered out and not be considered as an obstacle point because the slope normal vector is still within 10 degrees of the Z-axis direction.

1) sequencing all laser scanning points according to polar coordinates;

As shown in fig. 16, the conventional AGV driving motor control method is PI speed loop control, that is, the feedback information of the actual measured motor speed is used to realize accurate control of the rotational speed through Proportional (Proportional) control and Integral (Integral) control.

In which proportional and integral controlThe model is as follows: kv × (1+ sTv)/s, where the linear model of the motor is: km/(1+ sTm). Kv is the product of the proportional and integral gains; km is the motor torque constant; tm is the motor constant:

tv is generally taken as Tm, so that the pole of s-1/Tm in the motor model is eliminated.

This method is based on linear model analysis, however, the actual motor is not purely linear, especially at low rotational speeds the motor will exhibit a very strong non-linearity due to unmodeled coulomb friction and non-linear viscous friction. The most typical example is the motor dead zone, i.e. the PWM duty cycle is below a certain value, which does not enable the motor to run. When the ideal proportional-integral speed loop control is used for a nonlinear motor in AGV intelligent platform control, the following problems are solved:

3) When the AGV encounters a complex obstacle, the navigation module usually enables the AGV to run at a low speed, and at the moment, if the AGV collides with an undiscovered obstacle due to a sensor blind area, the variation of a method for judging the collision through the current change of the motor is insensitive or even fails due to the low damping ratio caused by nonlinearity. This is because the proportional and integral gains are actually very low at low speed, and the response of the speed loop is very slow when collision occurs, so that the output PWM command has a significant time delay to increase greatly, which finally shows that the current change is slow.

As shown in fig. 17, Kv and Km are feedback adjusted according to the speed of the motor. The adjustment rule of Kv is Kv0 (1+ max (0, w _ min-w) × p). Kv0 is the gain value of the original linear model, w is the rotation speed feedback, w _ min is the lowest rotation speed which needs to be adaptively adjusted, and p is the proportional value of gain adjustment. Thus, the gain is not adjusted during normal motor speed operation, but is increased proportionally and gradually below a speed threshold w _ min.

The control method disclosed in the embodiment has the advantages that:

1. and the superposition coverage of different sight distance angles is realized by combining the laser radar and the depth camera. In addition to serving AGV navigation, the depth camera itself can also be used in more advanced vision systems of the AGV, such as for target tracking.

2. And by adopting a laser filtering method with O (NLogN) complexity, noise in the laser data is effectively removed, and the interference on an AGV navigation system is avoided.

3. Obstacle point cloud parts are extracted from point cloud data of the depth camera, the problem of a blind area of 0.5 m of the depth camera is solved by combining the laser radar, and the complementation of the laser radar and the depth camera is realized.

4. By analyzing the linear model and the actual nonlinearity of the motor and dynamically adjusting the speed loop gain according to the actual speed feedback, the smooth and sensitive response of the full-speed section of the motor is realized, and finally the collision detection at low speed becomes possible.

5. With low cost sensor solutions, collisions of the AGV may not be avoided in actual operation. The method converts the collision into favorable information, adds the collision point into the obstacle map, and provides richer reference information for later navigation.

The present invention is not limited to the above-described alternative embodiments, and those skilled in the art can obtain other embodiments in any combination with each other according to the above-described embodiments, and any other embodiments in various forms can be obtained by anyone who can obtain other embodiments in the light of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the claims, and which the description is intended to be interpreted accordingly.

Claims

1. A self-adaptive AGV robot comprises a vehicle body, a navigation device arranged on the vehicle body and an execution device arranged on the vehicle body; the method is characterized in that:

the navigation device comprises a processor, a detection radar (21), a detection camera (20), a first filter and a second filter, wherein the detection radar (21), the detection camera (20), the first filter and the second filter are respectively connected with the processor;

the executing device comprises a base (1), a mechanical arm with six degrees of freedom arranged on the base and an executing steering engine (8) arranged at the tail end of the mechanical arm, wherein the mechanical arm comprises a first driving box (2), a four-bar mechanism (3), a second driving box (4), a sleeve shaft mechanical arm (5), a tail end transmission head (6) and a tail end executing head (7) which are sequentially connected; the base is provided with a first rotating shaft (104) rotating relative to the base, the first driving box is fixedly connected with the upper end of the first rotating shaft, the base is provided with a worm and gear driving assembly, and the worm and gear driving assembly is connected with the lower end of the first rotating shaft and synchronously transmits; a second rotating shaft (203) and a third rotating shaft (204) are arranged in the first driving box and are respectively driven by a second motor (201) and a third motor (202), and the four-bar linkage mechanism is enclosed into a parallelogram and is in matched transmission with the second rotating shaft and the third rotating shaft; the second driving box is fixed at the upper end of the four-bar linkage, the second driving box comprises a second box body, two direct-current brush motors (401) are arranged on the rear surface of the second box body, speed reduction transmission mechanisms connected with the two direct-current brush motors are arranged in the second box body respectively, the sleeve shaft machine arm comprises an inner output shaft (502) and an outer output shaft (501) which are connected with the speed reduction transmission mechanisms respectively for transmission, the outer output shaft is connected with the tail end transmission head and drives the tail end transmission head to rotate coaxially, and the inner output shaft extends into the tail end transmission head and is connected with the tail end execution head through a primary gear pair for transmission, so that the tail end execution head and the tail end transmission head rotate relatively;

the vehicle body comprises a frame and a driving system arranged below the frame; the frame comprises a pedestal (13), the pedestal comprises an outer edge strip (1301) and a grid-shaped middle net arranged in the outer edge strip, the middle net comprises a dense layer (1302) and an evacuation layer (1303), and the evacuation layer is attached to the lower part of the dense layer; a differential driving device is arranged at the center of the frame along the width direction, the differential driving device comprises a main control board and two square motor bases (14) which are arranged oppositely, a motor electrically connected with the main control board is arranged in each motor base, a rotating shaft of the motor is connected with a speed reducer, and the speed reducer is connected to a driving wheel (15); the middle parts of two wide edges of the frame are provided with a front guide assembly and a rear guide assembly, the front guide assembly and the rear guide assembly respectively comprise a front wheel seat (16) and a rear wheel seat (16 '), the front wheel seat is provided with a front guide wheel (17), and the rear wheel seat is provided with a rear guide wheel (17'); the motor base, the front wheel base and the rear wheel base are all provided with connecting clamping heads, and the connecting clamping heads comprise a first clamping head (18) and a second clamping head (19);

the connecting clamping heads on the motor base are positioned on the side surface of the motor base, and the connecting clamping heads on the front wheel base and the rear wheel base are respectively positioned on the upper end surface of the motor base; the top end of the first clamping head is provided with at least two second clamping heads; the evacuation layer and the dense layer respectively comprise transverse lattice bars and longitudinal lattice bars, the transverse lattice bars and the longitudinal lattice bars are mutually vertical, and the thickness of the transverse lattice bars is the same as that of the longitudinal lattice bars; the transverse lattice bars are parallel to the long edge direction of the outer edge bars, and the distance between the adjacent transverse lattice bars of the dense layer is equal to the thickness of the transverse lattice bars;

the detection camera (20) is used for scene identification and data acquisition to form point cloud data; filtering the point cloud according to the normal vector direction, and removing all points with the normal vector direction within 10 degrees from the Z-axis direction; sending the remaining points to a barrier map of the robot in the traveling process;

the detection radar (21) is used for scanning and detecting to obtain laser scanning points, filtering and screening the laser scanning points, and adding the laser scanning points corresponding to the obstacles to an obstacle map in a noise mode;

the first filter and the second filter are used for filtering the current of the second motor (201) and the current of the third motor (202) to obtain an instantaneous average current I _ avg;

the processor is used for appointing a new traveling path according to the obstacle map and appointing the AGV robot to advance or retreat according to the new traveling path, and the method specifically comprises the following steps:

the gain parameters of the second motor (201) or/and the third motor (202) are directly adjusted dynamically through the rotating speed, so that the nonlinear problem that the second motor (201) or/and the third motor (202) runs at a low speed is solved, and the change of the low-speed output current value of the second motor (201) or/and the third motor (202) tends to be linear;

judging that the AGV robot collides when the real-time current I-avg I > t of the second motor (201) or/and the third motor (202) at any moment, and immediately pausing the motion of the AGV robot at the moment; and evaluating the position of the collision point relative to the AGV robot through the direction of current change of the second motor (201) or/and the third motor (202);

standing for a waiting time T, and then controlling the AGV robot to rotate at a low speed of 360 degrees; if the current value returns to normal, judging that the current value meets the movement obstacle, and if the current value does not meet the movement obstacle, the current value leaves the current value, and returning to normal running; if the current value is increased during rotation, the obstacle is judged to still exist, the obstacle is confirmed to be a static obstacle, and the obstacle is added into the obstacle map.

2. An adaptive AGV robot according to claim 1 wherein: the four-bar linkage include first driving lever (301), second driving lever (303), first driven lever (302) and second driven lever (304), first driving lever is connected perpendicularly and rotates along with the axle with the second pivot, the second driving lever is connected perpendicularly and rotates along with the axle with the third pivot, first driven lever is articulated with first driving lever and is fixed to the second box, second driven lever one end is articulated with the second driving lever, the other end is articulated with first driven lever.

3. An adaptive AGV robot according to claim 1 wherein: the speed reduction transmission mechanism comprises two groups of transmission gear sets, each transmission gear set at least comprises a driving wheel and a driven wheel, a fourth rotating shaft (403) and a fifth rotating shaft (402) are arranged in the second box body, the two driving wheels are respectively connected with the two direct current brush motors, and the two driven wheels are respectively arranged on the fourth rotating shaft and the fifth rotating shaft; the fourth rotating shaft and the inner output shaft rotate coaxially, and the fifth rotating shaft and the outer output shaft rotate coaxially.

4. An adaptive AGV robot according to claim 3 wherein: and the first rotating shaft, the second rotating shaft, the third rotating shaft, the fourth rotating shaft and the fifth rotating shaft are all provided with torque sensors (9).

5. An adaptive AGV robot according to claim 1 wherein: the primary gear pair comprises a first driving bevel gear (10) coaxially arranged on the inner-layer output shaft and a first driven bevel gear (11) arranged on the end execution head, and the conicity of the first driving bevel gear and the conicity of the first driven bevel gear are both 45 degrees.

6. An adaptive AGV robot according to claim 1 wherein: the tail end transmission head comprises a fixing part (601) connected with the outer layer output shaft and a main body part (602) connected with the fixing part, the main body part is hollow, and a shaft hole used for being connected with the tail end execution head is formed in the side wall of the main body part.

7. Method for adaptive navigation of a robot according to any of claims 1-6, characterized in that it comprises a running path finding step and a post-collision processing step:

path finding step:

s01: scene recognition and data acquisition are carried out outside the range of 0.5 m through a detection camera (20) to form point cloud data; filtering the point cloud according to the normal vector direction, and removing all points with the normal vector direction within 10 degrees from the Z-axis direction; sending the remaining points to a barrier map of the robot in the traveling process; therefore, all horizontal surfaces can be filtered, and only real obstacle points are reserved; if the front is a gentle slope, the normal vector of the slope is still within 10 degrees of the Z-axis direction, so the point of the slope is still filtered out and is not taken as an obstacle point;

s02: scanning and detecting within a range of 0.5 m by a detection radar (21) to obtain laser scanning points, filtering and screening the laser scanning points, and adding the laser scanning points corresponding to the obstacles to an obstacle map in a noise point mode; the method is specifically divided into the following steps:

1) sequencing all laser scanning points according to polar coordinates;

4) discarding all points with the number of effective neighbor points less than or equal to 2;

s03: positioning according to the coordinates of the obstacle map, designating a new traveling path by the processor, and designating the AGV to advance according to the new traveling path;

s04: the gain parameters of the second motor (201) or/and the third motor (202) are directly adjusted dynamically through the rotating speed, so that the nonlinear problem that the second motor (201) or/and the third motor (202) runs at a low speed is solved, and the change of the low-speed output current value of the second motor (201) or/and the third motor (202) tends to be linear;

s05: using a first filter and a second filter for filtering the current of the second motor (201) and the third motor (202) to obtain an instantaneous average current I _ avg;

s06: judging that the AGV robot collides when the real-time current I-avg I > t of the second motor (201) or/and the third motor (202) at any moment, and immediately pausing the motion of the AGV robot at the moment; and evaluating the position of the collision point relative to the AGV robot through the direction of current change of the second motor (201) or/and the third motor (202);

s07: standing for a waiting time T, and then controlling the AGV robot to rotate at a low speed of 360 degrees; if the current value is recovered to be normal, judging that the current value meets the movement obstacle, and if the current value does not meet the movement obstacle, the current value leaves the current value, and recovering to be normal; if the current value is increased during rotation, judging that the obstacle still exists, confirming that the obstacle is a static obstacle, and adding the obstacle into an obstacle map at the moment;

s08: the processor designates the AGV robot to back down at a low speed, and re-executes steps S02 and S03.