WO2020000325A1

WO2020000325A1 - Apparatus, method and system for measuring speed of universal wheel, slip detection method, movable electronic apparatus, and method and route correction apparatus for correcting route

Info

Publication number: WO2020000325A1
Application number: PCT/CN2018/093467
Authority: WO
Inventors: 李北辰
Original assignee: 广州艾若博机器人科技有限公司
Priority date: 2018-06-28
Filing date: 2018-06-28
Publication date: 2020-01-02
Also published as: CN109511274A; CN208705351U

Abstract

Disclosed is an apparatus for measuring the speed of a universal wheel, wherein one end of a movable rod (3) is provided with a magnetic element (5), and the other end thereof is connected to a universal wheel (1) by means of a transmission mechanism (2); a linear Hall sensor (4) is located at one side of the movable rod (3) and faces the magnetic element (5); the movable rod (3) moves, with the rotation of the universal wheel (1), in a cyclic reciprocating motion by means of the transmission mechanism (2), so as to drive the magnetic element (5) to move in a cyclic reciprocating motion close to and away from the linear Hall sensor (4); the linear Hall sensor (4) continuously outputs analog signal values during the cyclic reciprocating motion of the magnetic element (5); and the angles of rotation of the universal wheel (1), with respect to an initial state at different times, are calculated based on the analog signal values output by the linear Hall sensor (4) in real time and the preset correspondence relationship to further calculate the speed of rotation of the universal wheel (1) in real time. The apparatus can acquire continuous signals and quantize the speed of the universal wheel (1), thereby facilitating the slip detection and route correction of a wheeled mobile robot. A method and system for measuring the speed of a universal wheel, a slip detection method, a portable electronic device, and a route correction method and apparatus are further provided.

Description

Universal wheel speed measurement device, method and system, slip detection method, movable electronic equipment, path correction method and device

Technical field

The invention relates to the field of robots, and in particular, to a universal wheel speed measurement device, method and system, a slip detection method, a movable electronic device, a path correction method and device.

Background technique

With the development of society and technological progress, smart homes are getting closer to people's lives. At present, an intelligent cleaning robot is gradually entering ordinary households, instead of manually performing floor cleaning tasks. This type of intelligent cleaning robot is usually supported by two driving wheels and a driven wheel. The driving wheels are directly driven by the motor to provide forward power. The driven wheels generally include universal wheels and auxiliary wheels to help maintain balance.

However, when the ground conditions are more complicated, the drive wheels often slip. For example, the ground is relatively smooth or the robot is stranded. At this time, although the drive wheels continue to rotate, the robot cannot run normally. The rolling distance of the drive wheels and the robot The sliding distance is not consistent. However, at this time, the robot control system still assumes that the robot is in a normal working state. Therefore, the robot will continue to work until the power is lower than a certain value and when it is no power, it will stop working, causing a lot of waste of electrical energy.

In view of this problem, the existing cleaning robots generally determine whether the driving wheels of the robot are slipping by detecting the motion state of the universal wheel.

For example, a Chinese invention patent application with patent application number 201510013410.4 discloses a universal wheel speed measurement device, which is connected to the universal wheel through a transmission mechanism. During the rolling of the universal wheel, the linkage disk is driven by the cam on the universal wheel The up and down movement causes the flange on the linkage plate to trigger the opening and closing of the switch of the detection circuit board (for example, to trigger the blocking and turning on of the infrared signal). When the switch is always closed or opened, the cleaning robot is determined Slipping occurs.

In another Chinese invention patent application with a patent application number of 201510291805.0, it discloses a universal wheel motion state detection device for a sweeping robot, which is connected to the universal wheel through a transmission mechanism, the chuck is connected to the transmission mechanism, and the universal When the wheel rolls, the chuck is rotated horizontally through a transmission device. The chuck is provided with a plurality of sets of convex teeth, and the ray transmitter and the ray receiver are provided on both sides of the tine. When the rays come out, it is judged that the chuck is in a rotating state, and the cleaning robot is in a normal moving state; when the ray receiver cannot receive rays or keeps receiving rays, it is judged that the chuck is in a stopped state, and the cleaning robot is in a stopped state or occurs. Idling.

In the prior art, the following methods have been used to detect whether the robot is slipping:

(1) The above structure simply judges whether the universal wheel is in motion or not, it cannot distinguish between the stopped movement state of the robot and the idling state of the driving wheel, and it cannot effectively detect the occurrence of slippage of the robot;

(2) The above structure can only detect the slip phenomenon of the robot by judging the stop motion state of the universal wheel, and cannot effectively determine the situation when the speed of the universal wheel and the speed of the driving wheel are inconsistent. When this happens, the robot assumes that the robot is in a normal working state. Therefore, the robot still obtains the movement displacement of the robot at the speed of two driving wheels, causing an error;

(3) The above structure obtains a discrete signal based on the rotation of the universal wheel, and there is a delay in detecting the occurrence of slippage in the robot. For example, when slippage occurs at any time, using the scheme of application number 201510013410.4 to perform slippage detection requires a long time. (For example, the set longest scrolling period of the scroll wheel) to determine when the switch is always closed or open, thereby determining that the robot is slipping and responding.

Summary of the invention

The purpose of the embodiments of the present invention is to provide a universal wheel speed measurement device, method and system, slip detection method, movable electronic equipment, path correction method and device, which can effectively overcome the existing technology by simply detecting whether the universal wheel is moving or not. Defects in judging whether the driving wheels of the robot are slipping, can obtain continuous signals and quantify the speed of the universal wheel, which is beneficial for subsequent applications.

In order to achieve the above object, an embodiment of the present invention provides a universal wheel speed measurement device, including a universal wheel, a transmission mechanism, a movable rod and a linear Hall sensor. One end of the movable rod is provided with a magnetic element, and the movable rod The other end is connected to the universal wheel through a transmission mechanism, and the linear Hall sensor is located on one side of the movable rod and is opposite to the magnetic element; the movable rod follows the universal wheel through the transmission mechanism. The rotation of the wheel makes a reciprocating circular motion, thereby driving the magnetic element to make a reciprocating circular motion toward and away from the linear Hall sensor, and the linear Hall sensor continuously outputs an analog signal value during the reciprocating circular motion of the magnetic element. .

Compared with the prior art, the universal wheel speed measuring device disclosed in the present invention is provided with a magnetic element at one end of the movable rod, and the other end is connected to the universal wheel through a transmission mechanism. The Hall sensor is located on one side of the movable rod. Opposite to the magnetic element, the movable rod performs a reciprocating circular motion with the rotation of the universal wheel through the transmission mechanism, thereby driving the magnetic element to make a reciprocating circular motion toward and away from the linear Hall sensor. The linear Hall sensor continuously outputs an analog signal value during the reciprocating cyclic motion of the magnetic element, which can effectively overcome the existing defects of simply judging whether the universal wheel is moving to determine whether the driving wheel of the robot is slipping. It can obtain continuous signals and quantify the speed of the universal wheel, which is beneficial for subsequent applications.

As an improvement of the above solution, the transmission mechanism includes a first friction wheel and a second friction wheel, the first friction wheel and the second friction wheel are symmetrically connected through an eccentric shaft, and the eccentric shaft is in contact with the first friction wheel and The axis of the second friction wheel is asymmetric, the movable rod is in contact with the eccentric shaft, the first friction wheel and the second friction wheel are in close contact with the universal wheel, and the universal wheel During the rotation, the first friction wheel and the second friction wheel are driven to roll, thereby driving the movable rod to perform a reciprocating cycle motion with the rotation of the universal wheel.

As an improvement of the above solution, the device further includes a pressing member, which is used to press the first friction wheel and the second friction wheel so that the first friction wheel and the second friction wheel are respectively connected with the first friction wheel and the second friction wheel. The universal wheel abuts closely.

As an improvement of the above solution, the device further includes a mounting seat, and a lower part of the mounting seat is provided with a groove for accommodating the universal wheel, and an axle of the universal wheel is fixedly engaged with a side wall of the groove. The upper part of the mounting seat is provided with a receiving cavity for accommodating the first friction wheel and the second friction wheel, and the groove is provided with a symmetrical first opening and a second opening, and the first friction wheel passes through The first opening is in close contact with the universal wheel, and the second friction wheel is in close contact with the universal wheel through the second opening.

As an improvement of the above solution, the pressing member includes a mounting frame and a torsion ring, the mounting frame includes a first connection arm, a second connection arm, and a cross beam, one end of the first connection arm and one end of the second connection arm Connected by the crossbeam, and the torsion ring is sleeved on the crossbeam, the first friction wheel is rotatably connected to the other end of the first connection arm through a rotation shaft thereon, and the second friction wheel It is rotatably connected with the other end of the second connecting arm through a rotating shaft thereon.

As an improvement of the foregoing solution, a bracket is provided in the receiving cavity, and the bracket includes a first side wall, a second side wall, and a third side wall connected in sequence, and the first side wall and the third side wall are relatively distributed. The beam is engaged with the groove of the first side wall and the groove of the third side wall, and the torsion ring is distributed between the first side wall and the third side wall, and the first connection One end of the arm is provided with a stopper, one end of the torsion ring is in contact with the stopper, and the other end of the torsion ring is in contact with the inner surface of the second side wall, so that the torsion ring occurs. The first friction wheel and the second friction wheel are deformed and a restoring force is pressed to closely contact the universal wheel.

As an improvement to the above solution, the device further includes an upper cover provided with a pressing block, the pressing block is used to cooperate with the bracket to compress the other end of the torsion ring to the second side. The inner surface of the wall abuts.

As an improvement of the above solution, a rotation prevention post is also provided in the receiving cavity of the mounting base, a rotation prevention hole is provided on the upper cover, and the rotation prevention post is inserted into the rotation prevention hole to prevent the pressure block and The position of the bracket is shifted.

As an improvement of the foregoing solution, the rolling surfaces of the first friction wheel and the second friction wheel are both conical surfaces.

As an improvement of the above solution, the upper cover is further provided with a third opening and a fourth opening, a rolling surface of the first friction wheel protrudes from the third opening, and a rolling surface of the second friction wheel is The fourth opening extends.

An embodiment of the present invention further provides a universal wheel speed measurement method, which is applicable to the universal wheel speed measurement device according to any one of the foregoing, and includes steps:

Obtain the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear hall sensor in real time and a preset correspondence relationship; wherein the correspondence relationship is an analog output of the linear hall sensor A correspondence between a signal value and a rotation angle of the universal wheel relative to an initial state;

The rotation speed of the universal wheel is calculated in real time according to the rotation angle of the universal wheel relative to the initial state.

Compared with the prior art, the universal wheel speed measurement method disclosed by the present invention obtains the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear Hall sensor in real time and a preset corresponding relationship. The real-time calculation of the speed of the universal wheel according to the rotation angle of the universal wheel relative to the initial state can effectively solve the problem that the prior art cannot effectively quantify the speed of the universal wheel, and calculate the speed of the universal wheel in real time for the follow-up For skid detection and path correction.

As an improvement of the above solution, the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state is obtained by the following steps:

Acquiring a time-varying curve of an analog signal value output by the linear Hall sensor during the uniform motion of the universal wheel at a preset angular velocity;

Intercept the curve of the first period of the analog signal value of the linear Hall sensor with time, and sample the curve of the first period at a preset frequency. According to the signal value and time of each sample, The correspondence relationship obtains a list of correspondence relationships between the analog signal value of the linear Hall sensor and the rotation angle of the universal wheel with respect to the initial state; wherein the rotation angle of the universal wheel with respect to the initial state is equal to the angular velocity and Product of time.

As an improvement of the above solution, the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

θ = sin ^-1 [(aB + b) / r] + α

Wherein, B is an analog signal value of the magnetic element sensed by the linear Hall sensor, a and b are adjustment parameters, and r is an axis of the first / second friction wheel and an eccentric shaft. The distance from the intersection of the straight line where the axis is located to the bottom surface of the movable rod to the axis of the universal wheel, θ is the rotation angle of the universal wheel with respect to the initial state, and α is the standard angle.

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]}

Hnow is the current magnetic field size, Hmin is the minimum value of the magnetic field, Hmid is the median value of the magnetic field, Hmax is the maximum value of the magnetic field, and θ is the rotation angle of the universal wheel relative to the initial state.

As an improvement of the above solution, the real-time calculation of the rotation speed of the universal wheel according to the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

Where U is the voltage value output by the linear Hall sensor in real time, t is the time, θ is the rotation angle of the universal wheel relative to the initial state, and f (θ) is the rotation angle of the universal wheel relative to the initial state. As a function of the voltage value output by the linear Hall sensor in real time, w is the angular velocity of the universal wheel.

ω = 2π (θ2-θ1) / 180T

Among them, ω is the angular velocity of the universal wheel, T is the period of scanning the rotation angle of the universal wheel, θ1 is the rotation angle of the universal wheel detected in the previous period, and θ2 is the rotation angle of the universal wheel detected in the current period. ; Wherein T is far less than the rotation period of the universal wheel itself.

An embodiment of the invention also provides a universal wheel speed measurement system, including:

The universal wheel speed measurement device according to any one of the above, configured to output an analog signal value through the linear Hall sensor;

A controller configured to obtain the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear Hall sensor in real time and a preset correspondence relationship, and according to the rotation of the universal wheel relative to the initial state The angle calculates the rotation speed of the universal wheel in real time; wherein the correspondence relationship is the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state.

As an improvement of the above solution, the universal wheel speed measurement system further includes a signal collector for obtaining an analog signal value output by the linear Hall sensor during the universal wheel is moving at a uniform angular velocity at a preset speed. Curve over time

The controller is further configured to intercept a curve of a first period of an analog signal value of the linear Hall sensor over time, and sample the curve of the first period at a preset frequency. The corresponding relationship between the sampled signal value and time is used to obtain a list of the corresponding relationship between the analog signal value of the linear Hall sensor and the rotation angle of the universal wheel with respect to the initial state; The angle of rotation is equal to the product of the angular velocity and time.

As an improvement of the foregoing solution, the controller obtains a correspondence list between the analog signal value of the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state by the following formula:

θ = sin ^-1 [(aB + b) / r] + α

As an improvement of the above solution, the controller obtains the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state by the following formula:

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]}

As an improvement of the above solution, the controller obtains the rotation angle of the universal wheel relative to the initial state in real time to calculate the speed of the universal wheel rotation according to the following formula:

The controller obtains the rotation angle of the universal wheel relative to the initial state according to the following formula to calculate the rotation speed of the universal wheel in real time:

ω = 2π (θ2-θ1) / 180T

ω is the angular velocity of the universal wheel, T is the period of scanning the rotation angle of the universal wheel, θ1 is the rotation angle of the universal wheel detected in the previous period, and θ2 is the rotation angle of the universal wheel detected in the current period; where , T is far less than the rotation period of the universal wheel itself.

An embodiment of the present invention also provides a slip detection method, which is applicable to a movable electronic device. The movable electronic device includes a first driving wheel, a second driving wheel, and a universal wheel speed measurement device according to any one of the foregoing. , Including steps:

Calculate the rotation speed of the universal wheel in real time according to the rotation angle of the universal wheel relative to the initial state;

When the difference between the speed of the first driving wheel and the speed of the second driving wheel is less than a preset first speed threshold, it is determined that the movable electronic device performs linear motion; when the first driving wheel When the difference between the speed of the second driving wheel and the speed of the second driving wheel is greater than a preset first speed threshold, determining that the movable electronic device performs a curved movement;

If it is determined that the movable electronic device performs linear motion, calculate a first difference between the speed of the universal wheel and the speed of the first driving wheel or the second driving wheel at the current moment;

When the first difference is greater than a preset second speed threshold, recording a first duration where the first difference is greater than a preset first speed threshold, and when the first duration is greater than a preset first At a time threshold, determining that the movable electronic device is slipping;

If it is determined that the movable electronic device performs a curve motion, calculate the theoretical speed of the universal wheel according to the speed of the first driving wheel and the speed of the second driving wheel, and calculate the speed and the speed of the universal wheel at the current moment. The second difference of the theoretical speed;

When the second difference is greater than the second speed threshold, record a second duration where the second difference is greater than the second speed threshold; when the second duration is greater than a preset second time threshold, then It is determined that the movable electronic device is slipped. First or second drive wheel First or second drive wheel

Compared with the prior art, the slip detection method disclosed in the present invention obtains the speed of the universal wheel by changing in real time, and compares the speed of the universal wheel with the first driving wheel or the second driving according to different motion states of the movable electronic device. The comparison of the wheel speed or the reference speed can effectively detect the inconsistency between the driving wheel rolling distance and the movable electronic device sliding distance. The function is more complete and more conducive to popularization.

θ = sin ^-1 [(aB + b) / r] + α

As an improvement of the above solution, the corresponding relationship between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]}

ω = 2π (θ2-θ1) / 180T

As an improvement of the above solution, the method further includes the steps:

When the mobile electronic device is detected to slip at any time, and the mobile electronic device performs a linear motion forward, control the mobile electronic device to back K ₁ cm and turn P ₁ ° to avoid;

When slippage is detected at any time of the movable electronic device, and the movable electronic device performs a linear motion backward, control the movable electronic device to advance K ₂ cm and turn P ₂ ° to avoid;

When slippage of the movable electronic device is detected at any time, and the movable electronic device performs a curve movement forward, control the movable electronic device to back K ₃ cm and turn P ₃ ° to avoid;

When it is detected that the movable electronic device slips at any time, and the movable electronic device makes a curve movement backward, control the movable electronic device to advance K ₄ cm and turn P ₄ ° to avoid.

An embodiment of the present invention further provides a movable electronic device, where the movable electronic device includes a first driving wheel, a second driving wheel, a first encoder, a second encoder, and any of claims 1-10. The universal wheel speed measuring device, controller and memory;

The first encoder is configured to detect the speed of the first driving wheel in real time;

The second encoder is used to detect the speed of the second driving wheel in real time;

The controller is configured to execute the following program modules stored in the memory:

The universal wheel speed calculation module is configured to obtain the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear Hall sensor in real time and a preset correspondence relationship, and according to the universal wheel The rotation angle relative to the initial state is used to calculate the rotation speed of the universal wheel in real time; wherein the correspondence relationship is the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state. ;

A movement mode judging module, configured to determine that the movable electronic device performs a linear motion when a difference between a speed of the first driving wheel and a speed of the second driving wheel is less than a preset first speed threshold; When the difference between the speed of the first driving wheel and the speed of the second driving wheel is greater than a preset first speed threshold, determining that the movable electronic device performs a curved movement;

A first difference calculating module, if it is determined that the movable electronic device performs linear motion, calculating a first difference between the speed of the universal wheel and the speed of the first driving wheel or the second driving wheel at the current moment;

A first slip determination module, configured to record a first duration when the first difference is greater than a preset first speed threshold when the first difference is greater than a preset second speed threshold; When a duration is greater than a preset first time threshold, determining that the mobile electronic device is slipping;

A second difference calculation module, configured to calculate the theoretical speed of the universal wheel according to the speed of the first driving wheel and the speed of the second driving wheel if it is determined that the movable electronic device performs a curved movement, and calculate the current time A second difference between the speed of the universal wheel and the theoretical speed;

A second slip determination module, configured to record a second duration when the second difference is greater than a second speed threshold when the second difference is greater than a second speed threshold; when the second duration is greater than a preset A second time threshold, it is determined that the movable electronic device is slipping. First drive wheel or second drive wheel

As an improvement of the foregoing solution, the controller is further configured to execute the following program modules stored in the memory:

A first control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when slippage of the movable electronic device is detected at any time and the movable electronic device performs a linear motion forward And turning direction so that the movable electronic device backs up by K ₁ cm and turns P ₁ ° to avoid;

A second control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when slippage is detected at the movable electronic device and the movable electronic device performs a linear motion backward And the direction of rotation so that the movable electronic device advances K ₂ cm and turns P ₂ ° to avoid;

A third control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when the movable electronic device detects slippage at any time And turning direction to make the movable electronic device back K ₃ cm and turn P ₃ ° to avoid;

A fourth control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when slippage of the movable electronic device is detected at any time, and the movable electronic device performs a curved movement backward And turn the direction so that the movable electronic device advances K ₄ cm and turns P ₄ ° to avoid.

An embodiment of the present invention further provides a path correction method, including steps:

Adopting the slip detection method according to any one of the above to determine whether the movable electronic device has slipped;

When it is determined at any time that the mobile electronic device is slipping, record the time during which the mobile electronic device continues to slip;

Correct the path of the mobile electronic device according to the time during which the mobile electronic device continues to slip.

An embodiment of the present invention further provides a path correcting device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. The processor is implemented when the processor executes the computer program. Path correction method as described above.

An embodiment of the present invention further provides a computer-readable storage medium, where the computer-readable storage medium includes a stored computer program, wherein when the computer program runs, a device where the computer-readable storage medium is located is controlled to execute as described above. The path correction method described above.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded schematic view of a universal wheel speed measurement device in Embodiment 1 of the present invention.

FIG. 2 is a plan view of a mounting base in Embodiment 1 of the present invention.

FIG. 3 is another plan view of the mounting base in Embodiment 1 of the present invention.

Fig. 4 is a longitudinal sectional view of a universal wheel speed measuring device in Embodiment 1 of the present invention.

FIG. 5 is a perspective view of a universal wheel speed measurement device in Embodiment 1 of the present invention.

6 is a schematic flowchart of a universal wheel speed measurement method in Embodiment 2 of the present invention.

7 is a schematic diagram of a universal wheel speed measurement process in Embodiment 2 of the present invention.

8 is a schematic structural diagram of a universal wheel speed measurement system in Embodiment 3 of the present invention.

FIG. 9 is a schematic flowchart of a slip detection method in Embodiment 4 of the present invention.

FIG. 10 is a schematic diagram of a slip detection process in Embodiment 3 of the present invention.

FIG. 11 is a schematic structural diagram of a movable electronic device in Embodiment 5 of the present invention.

FIG. 12 is a schematic flowchart of a path correction method in Embodiment 6 of the present invention.

detailed description

In the following, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

1 to 5, a universal wheel speed measurement device provided by an embodiment of the present invention includes a universal wheel 1, a transmission mechanism 2, a movable rod 3, and a linear Hall sensor 4. One end of the movable rod 3 is provided with a magnetic element 5. , The other end of the movable rod 3 is connected to the universal wheel 1 through a transmission mechanism 2, and the linear Hall sensor 4 is located on one side of the movable rod 3 and is opposite to the magnetic element 5; The rod 3 makes a reciprocating circular motion with the rotation of the universal wheel 1 through the transmission mechanism 2, thereby driving the magnetic element 5 to make a reciprocating circular motion close to and 3 away from the linear Hall sensor 4. The sensor 4 continuously outputs an analog signal value during the reciprocating cycle of the magnetic element 5.

The magnetic element 5 includes a magnet and the like. It should be noted that, as long as the element capable of generating a magnetic field is within the protection scope of the present invention.

Based on the above solution, the universal wheel 1 can drive the magnetic element 5 to make a reciprocating cyclic motion toward and away from the linear Hall sensor 4, so that the linear Hall sensor 4 is in a reciprocating cyclic motion of the magnetic element 5. The analog signal value is continuously output, and the analog signal value continuously changes with time, so that the speed of the scroll wheel can be calculated in real time, which facilitates the slip detection and path correction of the wheeled mobile robot.

As shown in FIG. 1, the universal wheel speed measuring device further includes a mounting base 6, an upper cover 7 and a pressing member. The transmission mechanism 2 includes a first friction wheel 21 and a second friction wheel 22. The wheel 21 and the second friction wheel 22 are symmetrically connected through an eccentric shaft 23, and the axes of the eccentric shaft 23 and the first friction wheel 21 and the second friction wheel 22 are asymmetric, and the movable rod 3 and the eccentric shaft The shaft 23 abuts, the first friction wheel 21 and the second friction wheel 22 are in close contact with the outer surface of the universal wheel 1, respectively, and the universal wheel 1 drives the first friction wheel 21 when rotating The second friction wheel 22 rolls, thereby driving the movable rod 3 to perform a reciprocating cycle motion with the rotation of the universal wheel 1. As shown in FIG. 1, the universal wheel 1 is a drum wheel with a wide middle and narrow sides, and the first friction wheel 21 and the second friction wheel 22 are preferably rolling wheels having a tapered tooth surface to communicate with the drum. The universal wheel 1 cooperates to increase the contact area between the universal wheel 1 and the first friction wheel 21 and the second friction wheel 22, thereby effectively driving the first friction wheel 21 and the second friction wheel 22 to roll. It should be noted that as long as the surfaces capable of synchronously rotating the first friction wheel 21 and the second friction wheel 22 with the universal wheel 1 are within the protection scope of the present invention.

As shown in FIG. 2 to FIG. 3, a lower part of the mounting seat 6 is provided with a groove 61 for accommodating the universal wheel 1, and an axle of the universal wheel 1 is fixedly engaged with the groove 61. A side wall, an upper portion of the mounting seat 6 is provided with a receiving cavity 62 for receiving the first friction wheel 21 and the second friction wheel 22, and the groove 61 is provided with a symmetrical first opening 63 and a second opening 64 The first friction wheel 21 is in close contact with the universal wheel 1 through the first opening 63, and the second friction wheel 22 is in close contact with the universal wheel 1 through the second opening 64. Pick up. A bracket is provided in the receiving cavity 62, and the bracket includes a first side wall 621, a second side wall 622, and a third side wall 623 connected in this order, and the first side wall 621 and the third side wall 623 are relatively distributed. .

Referring to FIG. 1 to FIG. 4, the pressing member is used for pressing the first friction wheel 21 and the second friction wheel 22 such that the first friction wheel 21 and the second friction wheel 22 are respectively connected to the universal joint. Wheel 1 abuts tightly. The pressing member includes a mounting bracket 81 and a torsion ring 82. The mounting bracket 81 includes a first connecting arm 811, a second connecting arm 812, and a cross beam 813. One end of the first connecting arm 811 and the second connecting arm 812. One end is connected by the cross beam 813, and the torsion ring 82 is sleeved on the cross beam 813, and the first friction wheel 21 is rotatably connected with the other end of the first connecting arm 811 through a rotation shaft thereon. The second friction wheel 22 is rotatably connected to the other end of the second connecting arm 812 through a rotating shaft thereon. The beam 813 is engaged with the groove of the first side wall 621 and the groove of the third side wall 623, and the twist ring 82 is distributed between the first side wall 621 and the third side wall 623. One end of the first connecting arm 811 is provided with a stopper, one end of the torsion ring 82 is in contact with the stopper, and the other end of the torsion ring 82 is in contact with the inner surface of the second side wall 622. Therefore, the torsion ring 82 is deformed and a restoring force is generated to compress the first friction wheel 21 and the second friction wheel 22 to closely contact the universal wheel 1.

As shown in FIG. 4, the upper cover 7 is provided with a pressing block 71, which is used to cooperate with the bracket to press the other end of the torsion ring 82 and the second side wall 622 abuts. . An anti-rotation column 65 is also provided in the receiving cavity 62 of the mounting base 6, and an anti-rotation hole 72 is provided on the upper cover 7. The anti-rotation column 65 is inserted into the anti-rotation hole 72, which can effectively prevent all The positions of the pressing block 71 and the bracket are shifted, so that the torsion ring 82 is maintained in a deformed state to generate a restoring force to press the first friction wheel 21 and the second friction wheel 22.

When the upper cover 7 is installed in cooperation with the mounting base 6, the rotation prevention column 65 is inserted into the rotation prevention hole 72, and the pressing block 71 can cooperate with the bracket to compress the other of the torsion ring 82. One end of the second side wall 622 abuts, so that the torsion ring 82 is deformed and a restoring force is generated to compress the first friction wheel 21 and the second friction wheel 22 to closely abut the universal wheel 1. When the universal wheel 1 rotates, the surface friction force between the universal wheel 1 and the first friction wheel 21 and the second friction wheel 22 will drive the first friction wheel 21 and the second friction wheel 22 to rotate synchronously. The eccentric shaft 23 is not symmetrical with the centers of the first friction wheel 21 and the second friction wheel 22. Therefore, the eccentric shaft 23 is rotated around the axes of the first friction wheel 21 and the second friction wheel 22 as they rotate. The cardiac connection makes a circular motion, which in turn drives the movable rod 3 abutting it to make a reciprocating circular motion. The reciprocating circular motion of the movable rod 3 will drive the magnetic element 5 provided at one end to reciprocate toward and away from the linear Hall sensor 4 Cyclic motion, the magnetic field intensity sensed by the linear Hall sensor 4 is cyclically changed between gradually becoming stronger and weaker, and the linear Hall sensor 4 continuously outputs continuous changes during the reciprocating cyclic motion of the magnetic element 5 Analog signal value. When the universal wheel 1 stops rotating, the movable rod 3 remains motionless, and the magnetic element 5 provided at one end thereof also remains motionless. The intensity of the magnetic field sensed by the linear Hall sensor 4 remains unchanged. The sensor 4 outputs a constant analog signal value. According to the output analog signal value and the time change curve, the slope can be analyzed to obtain the real-time speed of the universal wheel 1, which is conducive to subsequent slip detection and path correction.

As shown in FIG. 5, the upper cover 7 is further provided with a third opening 73 and a fourth opening 74, and the rolling surface of the first friction wheel 21 protrudes from the third opening 73, and the second friction wheel The rolling surface of 22 protrudes from the fourth opening 74, so that the volume of the entire device can be compressed, and the layout of the components in the receiving cavity 62 is more compact. The upper cover 7 is also provided with a guide sleeve, and one end of the movable rod 3 protrudes from the guide sleeve. This setting can keep the movable rod 3 in balance and will not fall over during reciprocating circular motion.

6 is a schematic flowchart of a universal wheel speed measurement method provided in Embodiment 2 of the present invention, which is applicable to the above universal wheel speed measurement device, and includes steps:

S21. Obtain a rotation angle of the universal wheel 1 relative to an initial state at different times according to the analog signal value output by the linear Hall sensor 4 in real time and a preset correspondence relationship; wherein the correspondence relationship is the linear Hall The corresponding relationship between the analog signal value output by the sensor 4 and the rotation angle of the universal wheel 1 relative to the initial state;

S22. Calculate the rotation speed of the universal wheel 1 in real time through the rotation angle of the universal wheel 1 relative to the initial state at different times.

Specifically, when the output analog signal value is a voltage value, the real-time speed of the universal wheel 1 can be obtained by analyzing the slope of the output analog signal value and time, and analyzing its slope. In practical applications, the angular velocity of the universal wheel 1 can be calculated by the following formula:

Where U is the voltage value output by the linear Hall sensor 4 in real time, t is the time, θ is the rotation angle of the universal wheel 1 relative to the initial state, and f (θ) is the relative initial state of the universal wheel 1 The relationship between the rotation angle and the voltage value output by the linear Hall sensor 4 in real time, w is the angular velocity of the universal wheel 1.

In addition, the rotation speed of the universal wheel can also be obtained by the following formula:

ω = 2π (θ2-θ1) / 180T

Among them, ω is the angular velocity of the universal wheel 1, T is the period for detecting the rotation angle of the universal wheel 1, θ1 is the rotational angle of the universal wheel detected in the previous period, and θ2 is the universal wheel detected in the current period. Rotation angle. It should be noted that T is far less than the rotation period of the universal wheel 1 itself (for example, T <t / 100, t is the rotation period of the universal wheel 1), otherwise the calculated angular velocity will be larger error.

It can be understood that the linear velocity of the universal wheel 1 can be calculated by the angular velocity of the universal wheel 1, the specific formula is:

v = wr Equation (2)

Where v is the angular velocity of the universal wheel 1 and r is the radius of the universal wheel 1.

Preferably, the corresponding relationship between the analog signal value output by the linear Hall sensor 4 and the rotation angle of the universal wheel 1 relative to the initial state is obtained by a calibration method, specifically:

Obtaining a time-varying curve of the analog signal value output by the linear Hall sensor 4 during the uniform movement of the universal wheel 1 at a preset angular velocity;

Intercept the curve of the first cycle of the analog signal value of the linear Hall sensor 4 with time, sample the curve of the first cycle at a preset frequency, and according to the signal value and time of each sample Corresponding relationship between the analog signal value of the linear Hall sensor 4 and the rotation angle of the universal wheel 1 relative to the initial state; wherein the rotation angle of the universal wheel 1 relative to the initial state is equal to The product of said angular velocity and time.

In another preferred embodiment, the corresponding relationship between the analog signal value output by the linear Hall sensor 4 and the rotation angle of the universal wheel 1 with respect to the initial state is obtained by a formula conversion method, as shown in FIG. 7, The universal wheel 1 rotates, which drives the transmission mechanism to rotate. Set the displacement d of the magnetic element 5 relative to the initial position within the time Δt. The magnetic field intensity B sensed by the linear Hall sensor 44 and the displacement of the magnetic element 5 relative to the initial position are set. The linear function relationship of d is:

d = aB + b Equation (3)

Among them, a and b are adjustment parameters. As shown in FIG. 7, if the angle at which the first friction wheel 21 / the second friction wheel 22 rotates within the time Δt (that is, the rotation angle of the universal wheel 1) is θ, then the relationship can be obtained as:

θ = α + β Equation (4)

sinβ = d / r Equation (5)

According to formula (3), formula (4) and formula (5), we can get:

θ = sin ^-1 [(aB + b) / r] + α Formula (6)

Among them, B is an analog signal value of the magnet sensed by the linear Hall sensor 4, a and b are adjustment parameters, and r is an axial center of the first friction wheel 21 / second friction wheel 22 and the eccentric shaft 23 The distance from the intersection of the straight line where the axis of the axis lies with the bottom surface of the movable rod 3 to the axis of the universal wheel 1; in practical applications, r can be roughly estimated as the radius of the eccentric shaft 23 and the first friction The sum of the distances from the axial center of the wheel 21 / the second friction wheel 22 to the axial center of the eccentric shaft 23. Generally, B is an inductance intensity value sensed by the linear Hall sensor 44.

In addition to the methods disclosed above, the corresponding relationship between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel 1 relative to the initial state can be obtained according to the following formula:

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]} Formula (7)

It should be noted that the rotation of the universal wheel 1 will drive the magnetic element 5 to move up and down periodically. The linear Hall sensor 4 can detect that the magnitude of the magnetic field changes with the movement of the magnetic element 5. The linear Hall sensor 4 detects a periodically changing magnetic field signal. In the embodiment of the present invention, each time the universal wheel 1 rotates, the linear Hall sensor 4 generates a magnetic field signal with a sine-like function curve. When the magnetic element 5 is closest to the linear Hall sensor 4, the magnetic field intensity is the largest, which is the peak of the sine-like function curve. When the magnetic element 5 is farthest from the linear Hall sensor 4, the magnetic field The minimum intensity is the trough of the sine-like function curve. Therefore, the maximum and minimum values of the magnetic field strength are related to the distance between the magnetic element 5 and the linear Hall sensor 4, since the maximum distance and minimum value of the magnetic element 5 with respect to the linear Hall sensor 4 are determined Therefore, the maximum value and the minimum value of the magnetic field strength are also easily determined. Here, Hmin is the magnetic field strength when the magnetic element 5 is farthest from the linear Hall sensor 4, Hmax is the magnetic field strength when the magnetic element 5 is closest to the linear Hall sensor 4, and Hmid is the The magnetic field strength of the magnetic element 5 at the middle position between the furthest distance and the shortest distance is described, and Hnow is the magnetic field strength obtained in real time.

Then according to formula (6), the rotation angle of the universal wheel 1 relative to the initial state at different times can be obtained according to the time-varying inductance intensity value sensed by the linear Hall sensor 44, and the angular velocity and Line speed.

It should be noted that the universal wheel speed measurement method used in this embodiment can obtain the speed of the universal wheel 1 in real time according to the continuously changing analog signal. Compared with the prior art, which calculates the speed of the universal wheel 1 through discrete digital signals, The driving speed of the universal wheel 1 can be more accurately quantified as an effective reference for subsequent detection of slip and path correction.

8 is a schematic structural diagram of a universal wheel speed measurement system according to Embodiment 3 of the present invention, including:

The universal wheel speed measuring device 31 is configured to output an analog signal value through the linear Hall sensor 4. The universal wheel speed measuring device 31 adopts the universal wheel speed measuring device 31 disclosed in any one of the above embodiments.

The controller 32 is configured to obtain the rotation angle of the universal wheel 1 relative to the initial state at different times according to the analog signal value output by the linear Hall sensor 4 in real time and a preset correspondence relationship, and The rotation angle of the initial state in real time calculates the rotation speed of the universal wheel 1; wherein the correspondence relationship is the value of the analog signal output by the linear Hall sensor 4 and the rotation angle of the universal wheel 1 relative to the initial state Correspondence.

Preferably, the universal wheel speed measurement system further includes a signal collector for obtaining an analog signal value output by the linear Hall sensor 4 along with the universal wheel 1 moving at a uniform angular velocity at a preset speed. Time variation curve

The controller 32 is further configured to intercept the curve of the first period of the analog signal value of the linear Hall sensor 4 with time, and sample the curve of the first period at a preset frequency. The correspondence between each sampled signal value and time is used to obtain a correspondence list between the analog signal value of the linear Hall sensor 4 and the rotation angle of the universal wheel 1 relative to the initial state; wherein the universal wheel 1 The rotation angle relative to the initial state is equal to the product of the angular velocity and time.

In another preferred embodiment, the controller 32 obtains a correspondence list between the analog signal value of the linear Hall sensor 4 and the rotation angle of the universal wheel 1 with respect to the initial state by the following formula:

θ = sin ^-1 [(aB + b) / r] + α

Wherein, B is the analog signal value of the magnetic element 5 sensed by the linear Hall sensor 4, a and b are adjustment parameters, and r is the axis of the first friction wheel / second friction wheel and the eccentricity. The distance from the intersection of the straight line where the axis center of the shaft lies with the bottom surface of the movable rod to the axis center of the universal wheel, θ is the rotation angle of the universal wheel relative to the initial state, and α is the standard angle.

In addition to the manner disclosed above, the controller 32 may also obtain the correspondence between the analog signal value output by the linear Hall sensor 4 and the rotation angle of the universal wheel 1 relative to the initial state according to the following formula:

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]}

Among them, Hnow is the current magnetic field size, Hmin is the minimum value of the magnetic field, Hmid is the median value of the magnetic field, Hmax is the maximum value of the magnetic field, and θ is the rotation angle of the universal wheel 1 relative to the initial state.

For the implementation process and working process of the universal wheel speed measurement system in this embodiment, reference may be made to the above description of the universal wheel speed measurement method, and details are not described herein again.

9 is a schematic flowchart of a slip detection method according to Embodiment 4 of the present invention, which is applicable to a movable electronic device. The movable electronic device includes a first driving wheel, a second driving wheel, and any one of the above implementations. The disclosed universal wheel speed measuring device includes the steps:

S41. Obtain the rotation angle of the universal wheel 1 relative to the initial state at different times according to the analog signal value output by the linear Hall sensor 4 in real time and a preset correspondence relationship; wherein the correspondence relationship is the linear Hall The corresponding relationship between the analog signal value output by the sensor 4 and the rotation angle of the universal wheel relative to the initial state;

S42. Calculate the rotation speed of the universal wheel 1 in real time according to the rotation angle of the universal wheel 1 relative to the initial state;

S43. When the difference between the speed of the first driving wheel and the speed of the second driving wheel is less than a preset first speed threshold, determine that the movable electronic device performs linear motion; when the first When the difference between the speed of the driving wheel and the speed of the second driving wheel is greater than a preset first speed threshold, determining that the movable electronic device performs a curved movement;

S44. If it is determined that the movable electronic device performs linear motion, calculate a first difference between the speed of the universal wheel 1 and the speed of the first drive wheel or the second drive wheel at the current moment;

S45. When the first difference is greater than a preset first speed threshold, record a first duration in which the first difference is greater than a preset first speed threshold, and when the first duration is greater than a preset At a first time threshold, determining that the movable electronic device is slipping;

S46. If it is determined that the movable electronic device performs a curved motion, calculate the theoretical speed of the universal wheel 1 according to the speed of the first driving wheel and the speed of the second driving wheel, and calculate the universal wheel 1 at the current moment. The second difference between the speed and the theoretical speed;

S47. When the second difference is greater than the second speed threshold, record a second duration when the second difference is greater than the second speed threshold; when the second duration is greater than a preset second time threshold , It is determined that the movable electronic device is slipping.

It should be noted that the method disclosed in this embodiment is applicable to a Wheeled Mobile Robot (WMR). The wheeled mobile robot is composed of a vehicle body, two driving wheels, and a follower wheel. The follower wheel starts during the movement process. Supporting effect, its influence in the previous kinematic model is negligible. In recent years, research has been started on its motion state to detect the phenomenon that the robot slips or stops when it encounters an obstacle. The direction and speed of the wheeled mobile robot can be controlled by controlling the rotation speed and direction of the motors of the left and right drive wheels. When there is a speed difference between the left and right drive wheels, the wheeled mobile robot will turn, for example , The speed of the left driving wheel is -50cm / s, the speed of the right driving wheel is 50cm / s, and the wheeled mobile robot makes a turning movement at its center; and when the speed of the left driving wheel and the right driving wheel are both 50cm / s The wheeled mobile robot moves straight forward with its center.

In this embodiment, first determine different motion states of the movable electronic device, such as linear motion or curved motion, and then analyze whether the movable electronic device is slipping according to the situation. When the movable electronic device performs a linear motion and determines that the first difference between the speed of the universal wheel and the speed of the first drive wheel or the second drive wheel is greater than a preset second speed threshold, Record the first duration of the first drive wheel or the second drive wheel for which the first difference is greater than a preset first speed threshold, and determine that the first duration is greater than a preset first time threshold The movable electronic device slips; when it is determined that the movable electronic device performs a curve movement, and it is determined that the second difference between the speed of the universal wheel and the theoretical speed at the current moment is greater than a second speed threshold, the record is recorded. A second duration that is greater than a second speed threshold; a second duration that is greater than a second speed threshold; and when the second duration is greater than a preset second time threshold, it is determined that the movable electronic device is slipping. By accurately quantifying the speed of the universal wheel and applying it to slip judgment, it can not only detect the situation where the universal wheel stops spinning and the driving wheel is idling, but also detect the universal wheel still rotating but its rolling distance and driving wheel rolling distance. Inconsistent conditions, more complete functions, and meet the needs of practical applications.

In the following, taking FIG. 10 as an example, slip detection of a curved movement of a movable electronic device will be described. Let the first driving wheel be the left driving wheel K1 in the figure, and the second driving wheel be the left driving wheel K2 in the figure. When the movable electronic device 4 makes a left turn at O point at any time, assuming that the speed of the left driving wheel K1 is 50 cm / s and the speed of the right driving wheel K2 is 100 cm / s, according to the distance between each point and the O point Proportional relationship, for example, the distance s1 from the front universal wheel K3 to the O point is 80cm, and the distance s3 from the right drive wheel K2 to the O point is 100cm. It can be seen that the theoretical speed of the universal wheel K3 and the speed ratio of the right drive wheel K2 are 80 / 100 = 4/5; therefore, under normal driving conditions, the theoretical speed of the front-end universal wheel K3 should be 80 cm / s, and at the current moment, the actual speed of the universal wheel K3 and the theoretical speed of 80 cm / s When the second difference is greater than a preset second speed threshold, a second duration is recorded in which the second difference is greater than a preset second speed threshold, and when the second duration is greater than a preset second time threshold , It is determined that the movable electronic device 4 has slipped.

When a slip of the mobile electronic device is detected, a preset avoidance strategy is required to get rid of the slip state, for example, when the slip of the mobile electronic device is detected at any time, and the mobile electronic device performs a linear motion forward When the mobile electronic device is controlled to back K ₁ cm and turn P ₁ ° to avoid;

When it is detected that the movable electronic device slips at any time, and the movable electronic device makes a curve movement backward, the movable electronic device is controlled to advance K4cm and turn P4 ° to avoid.

11 is a schematic structural diagram of a movable electronic device according to Embodiment 5 of the present invention. The movable electronic device includes a first driving wheel 51, a second driving wheel 52, a first encoder 53, and a second encoding. Device 54, the universal wheel speed measuring device 55, the controller 56, and the memory 57 according to the above item; wherein,

The first encoder 53 is configured to detect the speed of the first driving wheel 51 in real time;

The second encoder 54 is configured to detect the speed of the second driving wheel 52 in real time;

The controller 56 is configured to execute the following program modules stored in the memory 57:

The universal wheel speed calculation module 571 is configured to obtain the rotation angle of the universal wheel 1 from the initial state at different times according to the analog signal value output by the linear Hall sensor 4 in real time and a preset correspondence relationship, and pass the different times The rotation angle of the universal wheel 1 relative to the initial state is calculated in real time by the rotation speed of the universal wheel 1; wherein the correspondence relationship is an analog signal value output by the linear Hall sensor 4 and the universal wheel 1 Correspondence between the rotation angles relative to the initial state;

A movement mode judging module 572 is configured to, when a difference between the speed of the first driving wheel 51 and the speed of the second driving wheel 52 is less than a preset first speed threshold, determine that the movable electronic device does Linear motion; when the difference between the speed of the first driving wheel 51 and the speed of the second driving wheel 52 is greater than a preset first speed threshold, determining that the movable electronic device performs a curved motion;

The first difference calculation module 573 calculates a first speed of the universal wheel 1 and a speed of the first drive wheel 51 or the second drive wheel 52 if it is determined that the movable electronic device performs linear motion. Difference

A first slip determination module 574, configured to record a first duration when the first difference is greater than a preset first speed threshold when the first difference is greater than a preset second speed threshold; When the first duration is greater than a preset first time threshold, determining that the mobile electronic device is slipping;

A second difference calculation module 575, configured to calculate the theoretical speed of the universal wheel according to the speed of the first driving wheel 51 and the speed of the second driving wheel 52 if it is determined that the movable electronic device performs a curved movement, Calculating a second difference between the speed of the universal wheel and the theoretical speed at the current moment;

A second slip determination module 576, configured to record a second duration when the second difference is greater than a second speed threshold when the second difference is greater than a second speed threshold; when the second duration is greater than a predetermined time When the second time threshold is set, it is determined that the movable electronic device is slipped.

Preferably, the controller 32 is further configured to execute the following program modules:

A first control module, configured to control the movement of the first driving wheel 51 and the second driving wheel 52 when slippage of the movable electronic device is detected at any time and the movable electronic device performs a linear motion forward The speed and direction of rotation so that the movable electronic device backs up by K ₁ cm and turns P ₁ ° to avoid;

A second control module, configured to control the movement of the first driving wheel 51 and the second driving wheel 52 when slippage of the movable electronic device is detected at any time and the movable electronic device performs a linear motion backward; The speed and direction of rotation so that the movable electronic device advances K ₂ cm to avoid turning P ₂ °;

A third control module, configured to control the movement of the first driving wheel 51 and the second driving wheel 52 when slippage of the movable electronic device is detected at any moment The speed and direction of rotation so that the movable electronic device moves backward K ₃ cm and turns P ₃ ° to avoid;

A fourth control module, configured to control the movement of the first driving wheel 51 and the second driving wheel 52 when slippage of the movable electronic device is detected at any time, and the movable electronic device performs a curved movement backward; The speed and direction of rotation are such that the movable electronic device advances K ₄ cm and turns P ₄ ° to avoid.

For the working principle of the movable electronic device in this embodiment, reference may be made to the foregoing specific description of the slip detection method, and details are not described herein again.

12 is a schematic flowchart of a path correction method according to Embodiment 6 of the present invention, including steps:

S61. Use the slip detection method disclosed in any one of the foregoing embodiments to determine whether the movable electronic device has slipped;

S62. When it is determined at any time that the mobile electronic device is slipping, record the time during which the mobile electronic device continues to slip;

S63. Correct the path of the mobile electronic device according to the time during which the mobile electronic device continues to slip.

Because for a mobile electronic device, the path recording is based on an encoder, when the mobile electronic device slips, if the path is still recorded with the speed and displacement recorded by the encoder, a positioning error will result. Therefore, during the time when the mobile electronic device continues to slip, stopping the speed and displacement recording path recorded by the encoder can effectively correct the path of the mobile electronic device, which is important for subsequent map construction and accurate positioning. effect.

An embodiment of the present invention also correspondingly provides a path correction device including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, Implement the path correction method described above.

An embodiment of the present invention also correspondingly provides a computer-readable storage medium, where the computer-readable storage medium includes a stored computer program, wherein when the computer program runs, a device where the computer-readable storage medium is located is controlled to perform the above The path correction method described.

An embodiment of the present invention also correspondingly provides a terminal device including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. The processor is implemented when the processor executes the computer program. The universal wheel speed measurement method or slip detection method according to any one of the above.

Those skilled in the art can understand that the schematic diagram is only an example of a terminal device, and does not constitute a limitation on the terminal device. It may include more or fewer components than shown in the figure, or combine some components or different components. For example, the terminal device may further include an input / output device, a network access device, and a bus. The so-called processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), ready-made Field-Programmable Gate Array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor, or the processor may be any conventional processor, etc. The processor is a control center of a terminal device, and uses various interfaces and lines to connect various parts of the entire terminal device.

The memory may be used to store the computer program and / or module, and the processor implements the terminal by running or executing the computer program and / or module stored in the memory, and calling data stored in the memory. Various functions of the device. The memory may mainly include a storage program area and a storage data area, where the storage program area may store an operating system, at least one application required by a function (such as a sound playback function, an image playback function, etc.), etc .; the storage data area may store Data (such as audio data, phone book, etc.) created based on the use of the mobile phone. In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disks, memory, plug-in hard disks, Smart Memory Card (SMC), and Secure Digital (SD) cards. , Flash card (Flash card), at least one disk storage device, flash memory device, or other volatile solid-state storage device.

Wherein, when the module / unit integrated in the terminal device is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the present invention implements all or part of the processes in the method of the foregoing embodiment, and may also be completed by a computer program instructing related hardware. The computer program may be stored in a computer-readable storage medium. The computer When the program is executed by a processor, the steps of the foregoing method embodiments can be implemented. The computer program includes computer program code, and the computer program code may be in a source code form, an object code form, an executable file, or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, a recording medium, a U disk, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, a read-only memory (ROM, Read-Only Memory) , Random Access Memory (RAM, Random Access Memory), electric carrier signals, telecommunication signals, and software distribution media. It should be noted that the content contained in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdictions. For example, in some jurisdictions, the computer-readable medium Excludes electric carrier signals and telecommunication signals.

An embodiment of the present invention also provides a computer-readable storage medium, which is characterized in that the computer-readable storage medium includes a stored computer program, wherein the computer-readable storage medium is controlled when the computer program runs. The device where it is located performs the universal wheel speed measurement method or slip detection method described in any one of the above.

It should be noted that the device embodiments described above are only schematic, and the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical Units, which can be located in one place or distributed across multiple network units. Some or all of the modules may be selected according to actual needs to achieve the objective of the solution of this embodiment. In addition, in the drawings of the embodiment of the device provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines. Those of ordinary skill in the art can understand and implement without creative efforts.

The above is a preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principles of the present invention, several improvements and retouches can be made. It is the protection scope of the present invention.

Claims

A universal wheel speed measuring device is characterized by comprising a universal wheel, a transmission mechanism, a movable rod and a linear Hall sensor. One end of the movable rod is provided with a magnetic element, and the other end of the movable rod is connected with the transmission mechanism through a transmission mechanism. The universal wheel is connected, and the linear Hall sensor is located on one side of the movable rod and is opposite to the magnetic element; the movable rod makes a reciprocating cycle movement with the rotation of the universal wheel through the transmission mechanism Therefore, the magnetic element is driven to make a reciprocating cyclic motion toward and away from the linear Hall sensor, and the linear Hall sensor continuously outputs an analog signal value during the reciprocating cyclic motion of the magnetic element.
The universal wheel speed measuring device according to claim 1, wherein the transmission mechanism comprises a first friction wheel and a second friction wheel, and the first friction wheel and the second friction wheel are symmetrically connected through an eccentric shaft, so The eccentric shaft is asymmetric to the axes of the first friction wheel and the second friction wheel, the movable rod is in contact with the eccentric shaft, and the first friction wheel and the second friction wheel are respectively in contact with the million The steering wheel abuts tightly, and when the universal wheel rotates, the first friction wheel and the second friction wheel are driven to roll, thereby driving the movable rod to perform a reciprocating cycle motion with the rotation of the universal wheel.
The universal wheel speed measuring device according to claim 2, wherein the device further comprises a pressing member for pressing the first friction wheel and the second friction wheel so that the The first friction wheel and the second friction wheel are in close contact with the universal wheel, respectively.
The universal wheel speed measuring device according to any one of claims 3, characterized in that the device further comprises a mounting base, and a lower part of the mounting base is provided with a groove for accommodating the universal wheel, and the universal wheel The axle of the wheel is fixedly clamped to the side wall of the groove. The upper part of the mounting seat is provided with a receiving cavity for receiving the first friction wheel and the second friction wheel. The groove is provided with a symmetrical first An opening and a second opening, the first friction wheel closely contacts the universal wheel through the first opening, and the second friction wheel closely contacts the universal wheel through the second opening .
The universal wheel speed measuring device according to claim 4, wherein the pressing member includes a mounting bracket and a torsion ring, the mounting bracket includes a first connecting arm, a second connecting arm, and a cross beam, and the first One end of the connecting arm and one end of the second connecting arm are connected through the cross beam, and the torsion ring is sleeved on the cross beam. The first friction wheel is connected to the other of the first connecting arm through a rotation shaft thereon. One end is rotatably connected, and the second friction wheel is rotatably connected to the other end of the second connecting arm through a rotation shaft thereon.
The universal wheel speed measuring device according to claim 5, wherein a bracket is provided in the receiving cavity, and the bracket includes a first side wall, a second side wall, and a third side wall connected in sequence, and The first side wall and the third side wall are oppositely disposed, the beam is engaged with the first groove and the third side wall, and the torsion ring is distributed between the first side wall and the first side wall. Between three side walls, a stopper is provided at one end of the first connecting arm, one end of the torsion ring abuts the stopper, and the other end of the torsion ring is on the inner surface of the second side wall. Abutting, so that the torsion ring is deformed and a restoring force is generated to press the first friction wheel and the second friction wheel to closely abut the universal wheel.
The universal wheel speed measuring device according to claim 6, wherein the device further comprises an upper cover, wherein the upper cover is provided with a pressing block, and the pressing block is used for cooperating with the bracket to press the The inner surface of the second side wall abuts on the other end of the torsion ring.
The universal wheel speed measuring device according to claim 7, wherein a rotation preventing post is further provided in the receiving cavity of the mounting seat, a rotation preventing hole is provided on the upper cover, and the rotation preventing post is inserted into the receiving chamber. Said rotation prevention hole prevents the position of the pressure block and the bracket from being offset.
The universal wheel speed measuring device according to claim 1, wherein the rolling surfaces of the first friction wheel and the second friction wheel are both conical surfaces.
The universal wheel speed measuring device according to claim 8, wherein the upper cover is further provided with a third opening and a fourth opening, and a rolling surface of the first friction wheel protrudes from the third opening, A rolling surface of the second friction wheel protrudes from the fourth opening.
A universal wheel speed measurement method, characterized in that it is applicable to the universal wheel speed measurement device according to any one of claims 1-10, comprising the steps of:

Obtain the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear hall sensor in real time and a preset correspondence relationship; wherein the correspondence relationship is an analog output of the linear hall sensor A correspondence between a signal value and a rotation angle of the universal wheel relative to an initial state;

The rotation speed of the universal wheel is calculated in real time according to the rotation angle of the universal wheel relative to the initial state.
The method for measuring the speed of a universal wheel according to claim 11, wherein the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state is obtained by the following steps:

Acquiring a time-varying curve of an analog signal value output by the linear Hall sensor during the uniform motion of the universal wheel at a preset angular velocity;

Intercept the curve of the first period of the analog signal value of the linear Hall sensor with time, and sample the curve of the first period at a preset frequency. According to the signal value and time of each sample, The correspondence relationship obtains a list of correspondence relationships between the analog signal value of the linear Hall sensor and the rotation angle of the universal wheel with respect to the initial state; wherein the rotation angle of the universal wheel with respect to the initial state is equal to the angular velocity and Product of time.
The method for measuring the speed of a universal wheel according to claim 11, wherein the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

θ = sin -1 [(aB + b) / r] + α

Wherein, B is an analog signal value of the magnetic element sensed by the linear Hall sensor, a and b are adjustment parameters, and r is an axis of the first / second friction wheel and an eccentric shaft. The distance from the intersection of the straight line where the axis is located to the bottom surface of the movable rod to the axis of the universal wheel, θ is the rotation angle of the universal wheel with respect to the initial state, and α is the standard angle.
The method for measuring the speed of a universal wheel according to claim 11, wherein the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]}

Hnow is the current magnetic field size, Hmin is the minimum value of the magnetic field, Hmid is the median value of the magnetic field, Hmax is the maximum value of the magnetic field, and θ is the rotation angle of the universal wheel relative to the initial state.
The method for measuring the speed of a universal wheel according to claim 11, wherein the speed of calculating the rotation of the universal wheel according to the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

Where U is the voltage value output by the linear Hall sensor in real time, t is the time, θ is the rotation angle of the universal wheel relative to the initial state, and f (θ) is the rotation angle of the universal wheel relative to the initial state. As a function of the voltage value output by the linear Hall sensor in real time, w is the angular velocity of the universal wheel.
The method for measuring the speed of a universal wheel according to claim 11, wherein the speed of calculating the rotation of the universal wheel according to the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

ω = 2π (θ2-θ1) / 180T

Among them, ω is the angular velocity of the universal wheel, T is the period of scanning the rotation angle of the universal wheel, θ1 is the rotation angle of the universal wheel detected in the previous period, and θ2 is the rotation angle of the universal wheel detected in the current period. ; Wherein T is far less than the rotation period of the universal wheel itself.
A universal wheel speed measurement system, comprising:

The universal wheel speed measurement device according to any one of claims 1 to 10, configured to output an analog signal value through the linear Hall sensor;

A controller configured to obtain the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear Hall sensor in real time and a preset correspondence relationship, and according to the rotation of the universal wheel relative to the initial state The angle calculates the rotation speed of the universal wheel in real time; wherein the correspondence relationship is the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state.
The universal wheel speed measurement system according to claim 17, wherein the universal wheel speed measurement system further comprises a signal collector for acquiring during the process of the universal wheel advancing at a uniform angular velocity at a preset speed A time-varying curve of an analog signal value output by the linear hall sensor;

The controller is further configured to intercept a curve of a first period of an analog signal value of the linear Hall sensor over time, and sample the curve of the first period at a preset frequency. The corresponding relationship between the sampled signal value and time is used to obtain a list of the corresponding relationship between the analog signal value of the linear Hall sensor and the rotation angle of the universal wheel with respect to the initial state; The angle of rotation is equal to the product of the angular velocity and time.
The universal wheel speed measurement system according to claim 17, wherein the controller obtains a correspondence between an analog signal value of the linear Hall sensor and a rotation angle of the universal wheel with respect to an initial state by the following formula Relation list:

θ = sin -1 [(aB + b) / r] + α

Wherein, B is an analog signal value of the magnetic element sensed by the linear Hall sensor, a and b are adjustment parameters, and r is an axis of the first / second friction wheel and an eccentric shaft. The distance from the intersection of the straight line where the axis is located to the bottom surface of the movable rod to the axis of the universal wheel, θ is the rotation angle of the universal wheel with respect to the initial state, and α is the standard angle.
The universal wheel speed measurement system according to claim 17, wherein the controller obtains an analog signal value output by the linear Hall sensor and a rotation angle of the universal wheel relative to an initial state by the following formula. Correspondence:

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]}

Hnow is the current magnetic field size, Hmin is the minimum value of the magnetic field, Hmid is the median value of the magnetic field, Hmax is the maximum value of the magnetic field, and θ is the rotation angle of the universal wheel relative to the initial state.
The universal wheel speed measurement system according to claim 17, wherein the controller obtains the rotation angle of the universal wheel relative to the initial state according to the following formula to calculate the rotation speed of the universal wheel in real time:

Where U is the voltage value output by the linear Hall sensor in real time, t is the time, θ is the rotation angle of the universal wheel relative to the initial state, and f (θ) is the rotation angle of the universal wheel relative to the initial state. As a function of the voltage value output by the linear Hall sensor in real time, w is the angular velocity of the universal wheel.
The universal wheel speed measurement system according to claim 17, wherein the controller obtains the rotation angle of the universal wheel relative to the initial state according to the following formula to calculate the rotation speed of the universal wheel in real time:

ω = 2π (θ2-θ1) / 180T

ω is the angular velocity of the universal wheel, T is the period of scanning the rotation angle of the universal wheel, θ1 is the rotation angle of the universal wheel detected in the previous period, and θ2 is the rotation angle of the universal wheel detected in the current period; where , T is far less than the rotation period of the universal wheel itself.
A slip detection method is applicable to a movable electronic device. The movable electronic device includes a first driving wheel, a second driving wheel, and a universal wheel speed measuring device according to any one of claims 1-10. It consists of steps:

Obtain the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear hall sensor in real time and a preset correspondence relationship; wherein the correspondence relationship is an analog output of the linear hall sensor A correspondence between a signal value and a rotation angle of the universal wheel relative to an initial state;

Calculate the rotation speed of the universal wheel in real time according to the rotation angle of the universal wheel relative to the initial state;

When the difference between the speed of the first driving wheel and the speed of the second driving wheel is less than a preset first speed threshold, it is determined that the movable electronic device performs linear motion; when the first driving wheel When the difference between the speed of the second driving wheel and the speed of the second driving wheel is greater than a preset first speed threshold, determining that the movable electronic device performs a curved movement;

If it is determined that the movable electronic device performs linear motion, calculate a first difference between the speed of the universal wheel and the speed of the first driving wheel or the second driving wheel at the current moment;

When the first difference is greater than a preset second speed threshold, recording a first duration of the first drive wheel or the second drive wheel where the first difference is greater than a preset first speed threshold, and when the When the first duration is greater than a preset first time threshold, determining that the mobile electronic device is slipping;

If it is determined that the movable electronic device performs a curve motion, calculate the theoretical speed of the universal wheel according to the speed of the first driving wheel and the speed of the second driving wheel, and calculate the speed and the speed of the universal wheel at the current moment. The second difference of the theoretical speed;

When the second difference is greater than the second speed threshold, record a second duration where the second difference is greater than the second speed threshold; when the second duration is greater than a preset second time threshold, then It is determined that the movable electronic device is slipped.
The slip detection method according to claim 23, wherein the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state is obtained by the following steps:

Acquiring a time-varying curve of an analog signal value output by the linear Hall sensor during the uniform motion of the universal wheel at a preset angular velocity;

Intercept the curve of the first period of the analog signal value of the linear Hall sensor with time, and sample the curve of the first period at a preset frequency. According to the signal value and time of each sample, The correspondence relationship obtains a list of correspondence relationships between the analog signal value of the linear Hall sensor and the rotation angle of the universal wheel with respect to the initial state; wherein the rotation angle of the universal wheel with respect to the initial state is equal to the angular velocity and Product of time.
The slip detection method according to claim 23, wherein a correspondence between an analog signal value output by the linear Hall sensor and a rotation angle of the universal wheel relative to an initial state is obtained by the following formula:

θ = sin -1 [(aB + b) / r] + α

Wherein, B is an analog signal value of the magnetic element sensed by the linear Hall sensor, a and b are adjustment parameters, and r is an axis of the first / second friction wheel and an eccentric shaft. The distance from the intersection of the straight line where the axis is located to the bottom surface of the movable rod to the axis of the universal wheel, θ is the rotation angle of the universal wheel with respect to the initial state, and α is the standard angle.
The slip detection method according to claim 23, wherein a correspondence between an analog signal value output by the linear Hall sensor and a rotation angle of the universal wheel relative to an initial state is obtained by the following formula:

θ = arcsin {(Hnow-Hmid) / [(Hmax-Hmin) / 2)]}

Hnow is the current magnetic field size, Hmin is the minimum value of the magnetic field, Hmid is the median value of the magnetic field, Hmax is the maximum value of the magnetic field, and θ is the rotation angle of the universal wheel relative to the initial state.
The slip detection method according to claim 23, wherein the rotation speed of the universal wheel is calculated in real time according to the rotation angle of the universal wheel relative to the initial state, and is obtained by the following formula:

Where U is the voltage value output by the linear Hall sensor in real time, t is the time, θ is the rotation angle of the universal wheel relative to the initial state, and f (θ) is the rotation angle of the universal wheel relative to the initial state. As a function of the voltage value output by the linear Hall sensor in real time, w is the angular velocity of the universal wheel.
The slip detection method according to claim 23, wherein the real-time calculation of the rotation speed of the universal wheel according to the rotation angle of the universal wheel relative to the initial state is obtained by the following formula:

ω = 2π (θ2-θ1) / 180T

ω is the angular velocity of the universal wheel, T is the period of scanning the rotation angle of the universal wheel, θ1 is the rotation angle of the universal wheel detected in the previous period, and θ2 is the rotation angle of the universal wheel detected in the current period; where , T is far less than the rotation period of the universal wheel itself.
The slip detection method according to claim 23, wherein the method further comprises the steps of:

When the mobile electronic device is detected to slip at any time, and the mobile electronic device performs a linear motion forward, control the mobile electronic device to back K 1 cm and turn P 1 ° to avoid;

When slippage is detected at any time of the movable electronic device, and the movable electronic device performs a linear motion backward, control the movable electronic device to advance K 2 cm and turn P 2 ° to avoid;

When slippage of the movable electronic device is detected at any time, and the movable electronic device performs a curve movement forward, control the movable electronic device to back K 3 cm and turn P 3 ° to avoid;

When it is detected that the movable electronic device slips at any time, and the movable electronic device makes a curve movement backward, control the movable electronic device to advance K 4 cm and turn P 4 ° to avoid.
A movable electronic device, characterized in that the movable electronic device comprises a first driving wheel, a second driving wheel, a first encoder, a second encoder, and the vehicle according to any one of claims 1-10. Speed measuring device and controller for wheel;

The first encoder is configured to detect the speed of the first driving wheel in real time;

The second encoder is used to detect the speed of the second driving wheel in real time;

The controller is configured to execute the following program modules stored in the memory:

The universal wheel speed calculation module is configured to obtain the rotation angle of the universal wheel relative to the initial state at different times according to the analog signal value output by the linear Hall sensor in real time and a preset correspondence relationship, and according to the universal wheel The rotation angle relative to the initial state is used to calculate the rotation speed of the universal wheel in real time; wherein the correspondence relationship is the correspondence between the analog signal value output by the linear Hall sensor and the rotation angle of the universal wheel relative to the initial state. ;

A movement mode judging module, configured to determine that the movable electronic device performs a linear motion when a difference between a speed of the first driving wheel and a speed of the second driving wheel is less than a preset first speed threshold; When the difference between the speed of the first driving wheel and the speed of the second driving wheel is greater than a preset first speed threshold, determining that the movable electronic device performs a curved movement;

A first difference calculating module, if it is determined that the movable electronic device performs linear motion, calculating a first difference between the speed of the universal wheel and the speed of the first driving wheel or the second driving wheel at the current moment;

A first slip determination module, configured to record a first duration when the first difference is greater than a preset first speed threshold when the first difference is greater than a preset second speed threshold; When a duration is greater than a preset first time threshold, determining that the mobile electronic device is slipping;

A second difference calculation module, configured to calculate the theoretical speed of the universal wheel according to the speed of the first driving wheel and the speed of the second driving wheel if it is determined that the movable electronic device performs a curved movement, and calculate the current time A second difference between the speed of the universal wheel and the theoretical speed;

A second slip determination module, configured to record a second duration when the second difference is greater than a second speed threshold when the second difference is greater than a second speed threshold; when the second duration is greater than a preset A second time threshold, it is determined that the movable electronic device is slipping.
The removable electronic device according to claim 30, wherein the controller is further configured to execute the following program modules stored in the memory:

A first control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when slippage of the movable electronic device is detected at any time and the movable electronic device performs a linear motion forward And turning direction so that the movable electronic device backs up by K 1 cm and turns P 1 ° to avoid;

A second control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when slippage is detected at the movable electronic device and the movable electronic device performs a linear motion backward And the direction of rotation so that the movable electronic device advances K 2 cm and turns P 2 ° to avoid;

A third control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when the movable electronic device detects slippage at any time, and the movable electronic device moves forward in a curved line And turning direction to make the movable electronic device back K 3 cm and turn P 3 ° to avoid;

A fourth control module, configured to control the rotation speed of the first driving wheel and the second driving wheel when slippage of the movable electronic device is detected at any time, and the movable electronic device performs a curve motion And turn the direction so that the movable electronic device advances K 4 cm and turns P 4 ° to avoid.
A path correction method, comprising the steps of:

Adopting the slip detection method according to claim 23 to determine whether the movable electronic device has slipped;

When it is determined at any time that the mobile electronic device is slipping, record the time during which the mobile electronic device continues to slip;

Correct the path of the mobile electronic device according to the time during which the mobile electronic device continues to slip.
A path correcting device, comprising a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, and the processor implements the claims when the computer program is executed. The path correction method described in 32.
A computer-readable storage medium, characterized in that the computer-readable storage medium includes a stored computer program, wherein when the computer program runs, a device where the computer-readable storage medium is located is controlled to execute the device as claimed in claim 32. The path correction method described above.