Lawn mower motion control method, system, device, storage medium and riding lawn mower

Abstract

The present invention discloses a lawn mower motion control method, system, device, storage medium and riding lawn mower. By improving the operation mode and motion control strategy of the riding lawn mower, the current position vector information of the universal joystick is obtained, and the current position vector information is converted into corresponding first and second voltage signals, and the first and second voltage signals are used to correspondingly control the rotation speed and direction of the left and right drive motors, so as to control the traveling speed and traveling direction of the whole riding lawn mower by controlling the rotation speed difference and rotation direction of the two drive wheels. The present invention can realize the control of the traveling speed and traveling direction of the riding lawn mower only by using one universal joystick. The user can control the movement of the riding lawn mower by single-hand operation, which greatly improves the operation convenience of the motion control of the whole riding lawn mower, and there is no need to install complicated components such as a steering mechanism and a forward and reverse gear shifting mechanism, which greatly reduces the equipment cost.

Description

Technical Field

[0001] The present invention relates to the technical field of lawn mowing equipment, and particularly to a method, a system, a device, a storage medium and a riding lawn mower for controlling the movement of a lawn mower. Background Art

[0002] A lawn mower is a mechanical device used for harvesting forage grass and trimming lawns, and it can cut forage grass and weeds in gardens. A lawn mower is also known as a grass cutter, a lawn trimmer, a lawn mower, or a weed trimmer. A lawn mower mainly consists of a frame, a cutter head, a mowing drive device, traveling wheels, and a control part. The cutter head is installed on the frame, and a mowing drive device is installed on the cutter head. A mowing blade is installed on the output shaft of the mowing drive device, and the mowing blade uses the high-speed rotation of the mowing drive device to trim the lawn.

[0003] Lawn mowers can be divided into handheld lawn mowers, push lawn mowers, and riding lawn mowers according to the traveling mode. Among them, riding lawn mowers are suitable for trimming lawns with a relatively large area. At present, there are the following two forms of the movement control (traveling speed and traveling direction (forward, backward, and turning) control) methods for the whole machine of a riding lawn mower:

[0004] 1. Steering wheel + foot pedal control. The steering wheel controls the traveling direction (turning), and the foot pedal controls the traveling speed (accelerator pedal) and the forward / backward switching (gear shifting pedal). This control method requires the installation of a steering mechanism and a forward / backward gear shifting mechanism on the lawn mower, and requires the cooperation of hands and feet for operation, with high costs and poor operation convenience;

[0005] 2. Left and right control handles + foot pedal control. Pushing the left and right control handles forward or backward simultaneously respectively realizes forward and backward movement, and pushing the left and right control handles forward and backward in sequence realizes turning. The foot pedal (accelerator pedal) controls the traveling speed. This control method requires the coordinated cooperation of the left and right hands to control the traveling direction, and at the same time requires the cooperation of hands and feet to realize the movement control of the whole machine, with a complex structure, high costs, and poor operation convenience.

[0006] In summary, it can be seen that the existing movement control methods for the whole machine of a riding lawn mower all have the problem of poor operation convenience. Therefore, how to improve the operation convenience of the movement control of the whole machine of a riding lawn mower is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0007] The purpose of the present invention is to provide a method, a system, a device, a storage medium and a riding lawn mower for controlling the movement of a lawn mower, so as to improve the operation convenience of the movement control of the whole machine of a riding lawn mower.

[0008] To achieve the above object of the present invention, according to the first aspect of the present invention, there is provided a lawn mower motion control method, which is applied to a riding lawn mower. The riding lawn mower includes a universal steering handle, a traveling mechanism, and a traveling drive mechanism, wherein,

[0009] The traveling mechanism includes a passive caster wheel, a left drive wheel, and a right drive wheel provided at the bottom of the riding lawn mower;

[0010] The traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel, and a right drive motor drivingly connected to the right drive wheel;

[0011] The lawn mower motion control method includes the following steps:

[0012] In response to an operation on the universal steering handle, obtain the current position vector information of the universal steering handle;

[0013] Generate a first voltage signal and a second voltage signal based on the current position vector information of the universal steering handle;

[0014] Based on the first voltage signal, control the rotation speed and rotation direction of the left drive motor, and based on the second voltage signal, control the rotation speed and rotation direction of the right drive motor to control the rotation speed and rotation direction of the left drive wheel and the right drive wheel.

[0015] Preferably, the obtaining of the current position vector information of the universal steering handle includes:

[0016] Obtain the current position information of the universal steering handle in a rectangular coordinate system;

[0017] Perform a rectangular coordinate system - polar coordinate system conversion on the current position information to obtain the current position vector information of the universal steering handle in the polar coordinate system.

[0018] Preferably, the current position vector information includes polar radius information and polar angle information. The polar radius information is used to represent the moving distance of the universal steering handle relative to the initial position, and the polar angle information is used to represent the rotation angle of the universal steering handle relative to the reference direction.

[0019] Preferably, the generating of the first voltage signal and the second voltage signal based on the current position vector information of the universal steering handle includes:

[0020] Look up a first voltage value matching the polar radius information and the polar angle information in a pre - constructed first polar radius - polar angle - voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generate the first voltage signal based on the first voltage value; and

[0021] Look up the second voltage value that matches the polar radius information and polar angle information in the pre - constructed second polar radius - polar angle - voltage relationship table based on the polar radius information and polar angle information of the current position vector information, and generate the second voltage signal based on the second voltage value.

[0022] Preferably, the controlling the rotational speed and rotation direction of the left drive motor based on the first voltage signal includes:

[0023] Determine the target rotational speed and rotation direction of the left drive motor based on the first voltage signal and the pre - constructed drive wheel rotational speed - voltage relationship formula;

[0024] Control the drive current of the left drive motor so that the left drive motor operates at the target rotational speed and rotation direction;

[0025] The controlling the rotational speed and rotation direction of the right drive motor based on the second voltage signal includes:

[0026] Determine the target rotational speed and rotation direction of the right drive motor based on the second voltage signal and the pre - constructed drive wheel rotational speed - voltage relationship formula;

[0027] Control the drive current of the right drive motor so that the right drive motor operates at the target rotational speed and rotation direction.

[0028] According to the second aspect of the present invention, the present invention provides a lawn mower motion control system, which is applied to a riding lawn mower. The riding lawn mower includes a universal steering handle, a walking mechanism, and a walking drive mechanism, wherein,

[0029] The walking mechanism includes passive universal wheels, a left drive wheel, and a right drive wheel provided at the bottom of the riding lawn mower;

[0030] The walking drive mechanism includes a left drive motor drivingly connected to the left drive wheel and a right drive motor drivingly connected to the right drive wheel;

[0031] The lawn mower motion control system includes:

[0032] A handle position vector information acquisition module, configured to acquire the current position vector information of the universal steering handle in response to an operation on the universal steering handle;

[0033] A voltage signal generation module, generating a first voltage signal and a second voltage signal based on the current position vector information of the universal steering handle;

[0034] The drive motor control module is used to control the rotation speed and rotation direction of the left drive motor based on the first voltage signal, and control the rotation speed and rotation direction of the right drive motor based on the second voltage signal, so as to control the rotation speed and rotation direction of the left drive wheel and the right drive wheel.

[0035] Preferably, the handle position vector information acquisition module includes:

[0036] The handle position information acquisition unit is used to acquire the current position information of the universal operating handle in the rectangular coordinate system;

[0037] The position information conversion unit is used to perform rectangular coordinate system - polar coordinate system conversion on the current position information to obtain the current position vector information of the universal operating handle in the polar coordinate system.

[0038] Preferably, the current position vector information includes polar radius information and polar angle information. The polar radius information is used to represent the moving distance of the universal operating handle relative to the initial position, and the polar angle information is used to represent the rotation angle of the universal operating handle relative to the reference direction.

[0039] Preferably, the voltage signal generation module includes:

[0040] The first voltage signal generation unit is used to look up the first voltage value matching the polar radius information and polar angle information in a pre - constructed first polar radius - polar angle - voltage relationship table based on the polar radius information and polar angle information of the current position vector information, and generate the first voltage signal based on the first voltage value; and

[0041] The second voltage signal generation unit is used to look up the second voltage value matching the polar radius information and polar angle information in a pre - constructed second polar radius - polar angle - voltage relationship table based on the polar radius information and polar angle information of the current position vector information, and generate the second voltage signal based on the second voltage value.

[0042] Preferably, the drive motor control module includes:

[0043] The first motor target state determination unit determines the target rotation speed and rotation direction of the left drive motor based on the first voltage signal and a pre - constructed drive wheel speed - voltage relationship formula;

[0044] The first motor control unit controls the drive current of the left drive motor so that the left drive motor operates at the target rotation speed and rotation direction;

[0045] The second motor target state determination unit determines the target rotation speed and rotation direction of the right drive motor based on the second voltage signal and a pre - constructed drive wheel speed - voltage relationship formula;

[0046] A second motor control unit controls the drive current of the right drive motor so that the right drive motor operates at the target rotational speed and in the rotational direction.

[0047] According to the third aspect of the present invention, there is provided a lawn mower motion control device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, any one of the lawn mower motion control methods described in the first aspect above is implemented.

[0048] According to the fourth aspect of the present invention, there is provided a computer-readable storage medium storing a computer program, which when executed by a processor, implements any one of the lawn mower motion control methods described in the first aspect above.

[0049] According to the fifth aspect of the present invention, there is provided a riding lawn mower, including a universal steering handle, a traveling mechanism, and a traveling drive mechanism, wherein,

[0050] The traveling mechanism includes passive universal wheels, a left drive wheel, and a right drive wheel provided at the bottom of the riding lawn mower;

[0051] The traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel, and a right drive motor drivingly connected to the right drive wheel;

[0052] The riding lawn mower further includes the lawn mower motion control device described in the third aspect above.

[0053] As can be seen from the above technical solutions, the present invention provides a lawn mower motion control method, system, device, storage medium, and riding lawn mower. By improving the control method and motion control strategy of the riding lawn mower, by obtaining the current position vector information of the universal steering handle, converting the current position vector information into corresponding first and second voltage signals, and using the first and second voltage signals to respectively control the rotational speed and direction of the left and right drive motors, thereby controlling the traveling speed and traveling direction of the entire riding lawn mower by controlling the rotational speed difference and rotational direction of the two drive wheels.

[0054] The present invention can achieve the control of the traveling speed and traveling direction of the riding lawn mower only by using one universal steering handle. The user can control the movement of the riding lawn mower by single-handed operation, greatly improving the manipulation convenience of the motion control of the entire riding lawn mower. Moreover, when using this method to control the riding lawn mower, there is no need to install complex components such as a steering mechanism and a forward and reverse gear shifting mechanism, greatly reducing the equipment cost.

[0055] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0057] The above additional aspects and / or advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0058] Figure 1 is a schematic flowchart of a lawn mower motion control method in a preferred embodiment of the present invention;

[0059] Figure 2 is a schematic diagram showing the current position of a universal control handle in a polar coordinate system in a preferred embodiment of the present invention;

[0060] Figure 3 is an analysis schematic diagram of a lawn mower turning clockwise when the center of the turn is on the right side of the right rear wheel in a preferred embodiment of the present invention;

[0061] Figure 4 is an analysis schematic diagram of a lawn mower turning clockwise when the center of the turn is between the right rear wheel and the left rear wheel in a preferred embodiment of the present invention;

[0062] Figure 5 is an analysis schematic diagram of a lawn mower turning counterclockwise and backing up when the center of the turn is on the left side of the left rear wheel in a preferred embodiment of the present invention;

[0063] Figure 6 is a schematic structural diagram of a lawn mower motion control system in a preferred embodiment of the present invention;

[0064] Figure 7 is a schematic structural diagram of a lawn mower motion control device in a preferred embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0065] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0066] As Figure 1 shown, an embodiment of the present invention provides a lawn mower motion control method, which is applied to a riding lawn mower. The riding lawn mower includes a universal steering handle, a traveling mechanism, and a traveling drive mechanism, where,

[0067] The traveling mechanism includes a passive caster wheel, a left drive wheel, and a right drive wheel provided at the bottom of the riding lawn mower;

[0068] The traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel, and a right drive motor drivingly connected to the right drive wheel;

[0069] The lawn mower motion control method may include the following steps:

[0070] S1. In response to an operation on the universal steering handle, obtain the current position vector information of the universal steering handle;

[0071] When it is necessary to make the riding lawn mower travel, the user controls the traveling state of the riding lawn mower by operating the universal steering handle. When the user operates the universal steering handle to deflect the universal steering handle around its central axis, the lawn mower motion control program is started, and first, the current position vector information after the deflection of the universal steering handle is obtained.

[0072] Specifically, the corresponding position after the deflection of the universal steering handle can be detected by a sensor. In this embodiment, a magnet is fixedly provided at the lowermost end of the universal steering handle, and a Hall sensor is provided below the magnet to sense the magnetic field change, so as to realize the detection of the position of the universal steering handle.

[0073] S2. Generate a first voltage signal and a second voltage signal based on the current position vector information of the universal steering handle;

[0074] After obtaining the current position vector information of the universal steering handle, analyze and process the current position vector information to obtain a first voltage signal and a second voltage signal corresponding to the current position vector information.

[0075] S3. Control the rotation speed and rotation direction of the left drive motor based on the first voltage signal, and control the rotation speed and rotation direction of the right drive motor based on the second voltage signal, so as to control the rotation speed and rotation direction of the left drive wheel and the right drive wheel.

[0076] Finally, the left drive motor and the right drive motor are correspondingly controlled to operate according to the first voltage signal and the second voltage signal obtained through analysis, and then the rotational speeds and rotation directions of the left drive wheel and the right drive wheel are controlled respectively through the left drive motor and the right drive motor. That is, the rotational speed and rotation direction of the left drive motor are controlled according to the first voltage signal, and the left drive wheel is driven through the left drive motor to cause corresponding changes in the rotational speed and rotation direction of the left drive wheel. At the same time, the rotational speed and rotation direction of the right drive motor are controlled according to the second voltage signal, and the right drive wheel is driven through the right drive motor to cause corresponding changes in the rotational speed and rotation direction of the right drive wheel, so as to realize the motion control of the whole riding lawn mower by operating the universal control handle.

[0077] In summary, this embodiment provides a method for controlling the motion of a lawn mower. First, in response to an operation on the universal control handle, the current position vector information of the universal control handle is obtained. Then, based on the current position vector information of the universal control handle, a first voltage signal and a second voltage signal are generated. Finally, based on the first voltage signal, the rotational speed and rotation direction of the left drive motor are controlled, and based on the second voltage signal, the rotational speed and rotation direction of the right drive motor are controlled to control the rotational speeds and rotation directions of the left drive wheel and the right drive wheel. By improving the control method and motion control strategy of the riding lawn mower, this embodiment obtains the current position vector information of the universal control handle, converts the current position vector information into corresponding first and second voltage signals, and uses the first and second voltage signals to correspondingly control the rotational speeds and directions of the left and right drive motors, so as to realize the control of the traveling speed and traveling direction of the whole riding lawn mower by controlling the rotational speed difference and rotation direction of the two drive wheels. This embodiment can realize the control of the traveling speed and traveling direction of the riding lawn mower only by using one universal control handle. The user can control the movement of the riding lawn mower with one hand, which greatly improves the operation convenience of the motion control of the whole riding lawn mower. Moreover, when using this method to control the riding lawn mower, there is no need to install complex components such as a steering mechanism and a forward / reverse gear shifting mechanism, which greatly reduces the equipment cost.

[0078] It should be noted that the traveling mechanism of the riding lawn mower in this embodiment can be a rear-wheel drive mechanism or a front-wheel drive mechanism. For a riding lawn mower with a rear-wheel drive mechanism, the passive universal wheel is installed at the front end of the bottom of the lawn mower and is responsible for steering. The left drive wheel and the right drive wheel are symmetrically installed on the left and right sides at the rear end of the bottom of the lawn mower and are responsible for driving the lawn mower forward; for a riding lawn mower with a front-wheel drive mechanism, the passive universal wheel is installed at the rear end of the bottom of the lawn mower and is responsible for steering. The left drive wheel and the right drive wheel are symmetrically installed on the left and right sides at the front end of the bottom of the lawn mower and are responsible for driving the lawn mower forward. Specifically, one passive universal wheel responsible for steering can be arranged in the middle of one end of the bottom of the lawn mower, or two can be symmetrically arranged on the left and right sides of one end of the bottom of the lawn mower. In this embodiment, the riding lawn mower cancels components such as a complex steering mechanism and a forward and reverse gear shifting mechanism from the structure. By controlling the rotational speed difference and rotation direction of the left drive wheel and the right drive wheel, the motion control of the riding lawn mower such as the traveling speed and traveling direction can be realized, while improving the operation convenience and greatly reducing the equipment cost.

[0079] In one embodiment, the obtaining of the current position vector information of the universal control handle includes:

[0080] Obtaining the current position information of the universal control handle in a rectangular coordinate system;

[0081] Performing a rectangular coordinate system - polar coordinate system conversion on the current position information to obtain the current position vector information of the universal control handle in the polar coordinate system.

[0082] For the control method of the riding lawn mower using a universal control handle, in order to obtain the current vector position information of the control handle, the current position information of the universal control handle in the rectangular coordinate system can be obtained first, and then the current position information is subjected to a rectangular coordinate system - polar coordinate system conversion to obtain the current position vector information of the universal control handle in the polar coordinate system.

[0083] Specifically, in one embodiment, the current position vector information includes a polar radius information and a polar angle information. The polar radius information is used to represent the moving distance of the universal control handle relative to the initial position, and the polar angle information is used to represent the rotation angle of the universal control handle relative to the reference direction.

[0084] It should be noted that the universal operation handle is tilted at a certain angle relative to the direction of the initial state with its rotation connection point as the center. Therefore, the moving distance of the universal control handle relative to the initial position can specifically be the distance between the position of a certain preset point on the universal control handle projected in the polar coordinates and the pole (initial position) of the polar coordinate system. Preferably, the preset point can be the lowest end point of the universal control handle, which is convenient for detecting the position of the preset point.

[0085] Specifically, the reference direction may be directly in front of the riding lawn mower.

[0086] As Figure 2 shown, it is a schematic diagram of the current position representation of the universal control handle in the polar coordinate system. In the figure, point M is the position of the projection of a preset point on the universal control handle in the polar coordinates, that is, the current position of the universal control handle (at this time, the universal control handle is in the first quadrant). The positive direction of the Y coordinate is the reference direction. In the figure, R represents the maximum moving distance of the universal control handle. At this time, the current position vector information of the universal control handle is M = (ρ, θ).

[0087] In one embodiment, generating the first voltage signal and the second voltage signal based on the current position vector information of the universal control handle includes:

[0088] Searching for a first voltage value that matches the polar radius information and the polar angle information in a pre-constructed first polar radius - polar angle - voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generating a first voltage signal based on the first voltage value; and

[0089] Searching for a second voltage value that matches the polar radius information and the polar angle information in a pre-constructed second polar radius - polar angle - voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generating a second voltage signal based on the second voltage value.

[0090] In this embodiment, when executing the generation of the first voltage signal and the second voltage signal based on the current position vector information of the universal control handle, the voltage value corresponding to the current position of the universal control handle can be determined by looking up a table according to the polar radius information and the polar angle information in the current position information of the universal control handle, and the corresponding voltage signal can be generated according to the voltage value obtained by looking up the table.

[0091] Specifically, the first polar radius - polar angle - voltage relationship table and the second polar radius - polar angle - voltage relationship table can be calibrated and stored in the controller for controlling the travel of the riding lawn mower before the riding lawn mower leaves the factory.

[0092] Specifically, the first polar radius - polar angle - voltage relationship table and the second polar radius - polar angle - voltage relationship table can be constructed in the following ways of Table (1) and Table (2), where Table (1) is the first polar radius - polar angle - voltage relationship table and Table (2) is the second polar radius - polar angle - voltage relationship table.

[0093] As shown in Table (1) and Table (2), the numbers in the first row of the table represent the polar angle information θ (unit: °) in the current position vector information of the universal operating handle, and the numbers in the first column represent the polar radius information ρ (unit: mm) in the current position vector information of the universal operating handle. Starting from the cell in the second row and second column, the numbers in each cell represent the voltage value (unit: V) corresponding to the current position. For example, when the polar angle information θ in the current position vector information of the universal operating handle is 90° and the polar radius information ρ is 10 mm, the corresponding first voltage value can be found from Table (1) to be 2.60 V, and the corresponding second voltage value can be found from Table (2) to be 1.50 V. After finding the corresponding first voltage value and second voltage value in the table, the corresponding first voltage signal and second voltage signal are output according to the first voltage value and the second voltage value respectively.

[0094] In this embodiment, the maximum value of the polar radius is 30, that is, the maximum moving distance of the universal operating handle is 30 mm. The granularity of the moving distance discretization in Table (1) and Table (2) is 1 mm. It should be noted that, in order to facilitate the display of the corresponding first voltage value and second voltage value within a larger angle range (0° to 180°), the granularity of the angle discretization in Table (1) and Table (2) is 10°. In actual application, the granularity of the angle discretization in the first polar radius - polar angle - voltage relationship table and the second polar radius - polar angle - voltage relationship table is 1°. In addition, it should be noted that Table (1) and Table (2) only show the values of the corresponding first voltage value and second voltage value when the universal operating handle is in the first quadrant and the fourth quadrant (that is, the polar angle θ is in the range of 0° to 80°). When the universal operating handle is in the corresponding position in the second quadrant and the third quadrant region (that is, the polar angle θ is in the range of 0° to -180°), the first polar radius - polar angle - voltage relationship table shown in Table (1) is set as the second polar radius - polar angle - voltage relationship table, and the second polar radius - polar angle - voltage relationship table shown in Table (2) is set as the first polar radius - polar angle - voltage relationship table. At the same time, a negative sign "-" is added in front of the polar angle θ. That is, when the polar angle information θ in the current position vector information of the universal operating handle is -90° and the polar radius information ρ is 10 mm, the corresponding first voltage value can be found from Table (2) to be 1.50 V, and the corresponding second voltage value can be found from Table (1) to be 2.60 V.

[0095] Table (1): First Polar Radius - Polar Angle - Voltage Relationship Table

[0096]

[0097]

[0098] Table (2): Second Polar Radius - Polar Angle - Voltage Relationship Table

[0099]

[0100]

[0101] In one embodiment, controlling the rotational speed and direction of the left drive motor based on the first voltage signal includes:

[0102] Determining the target rotational speed and direction of the left drive motor based on the first voltage signal and a pre-established relationship between the rotational speed of the drive wheel and the voltage;

[0103] Controlling the drive current of the left drive motor so that the left drive motor operates at the target rotational speed and in the target direction;

[0104] Controlling the rotational speed and direction of the right drive motor based on the second voltage signal includes:

[0105] Determining the target rotational speed and direction of the right drive motor based on the second voltage signal and a pre-established relationship between the rotational speed of the drive wheel and the voltage;

[0106] Controlling the drive current of the right drive motor so that the right drive motor operates at the target rotational speed and in the target direction.

[0107] Specifically, the relationship between the rotational speed of the drive wheel and the voltage can be calibrated before the riding lawn mower leaves the factory and stored in the controller for controlling the travel of the riding lawn mower.

[0108] In design, a linear relationship can be established between the rotational speed of the drive wheel and the corresponding voltage signal. Let the rotational speed of the drive wheel be n (when n is positive, it indicates that the drive wheel rotates forward; when n is negative, it indicates that the drive wheel rotates backward), and the voltage signal be u. Then the relationship between the rotational speed of the drive wheel and the voltage can be expressed as u = an + b, where a and b are constants. The specific values of the constants a and b in the relationship between the rotational speed of the drive wheel and the voltage can be determined according to the target voltage signal range and the target drive wheel rotational speed range.

[0109] For example, when the voltage output range of the target voltage signal (the first voltage signal, the second voltage signal) is 0.2V to 4.8V, and the target drive rotational speed range is -1128 rpm to 3000 rpm. When the first voltage signal / second voltage signal is set to 0.2V, the rotational speed of the left drive wheel / right drive wheel is -1128 rpm (where the negative sign indicates that the drive wheel rotates backward), and when the first voltage signal / second voltage signal is 4.8V, the rotational speed of the left drive wheel / right drive wheel is 3000 rpm. Based on these two special points, the values of the constants a and b can be obtained, and then the relationship between the rotational speed of the drive wheel and the voltage can be obtained as:

[0110] u = 1.1 / 1000 * n + 1.5.

[0111] It should be noted that the corresponding relationships among the polar radius, polar angle, and voltage in the first polar radius - polar angle - voltage relationship table and the second polar radius - polar angle - voltage relationship table can be established according to the motion states (forward, backward, acceleration, deceleration, turning) of the lawn mower that need to be achieved at each position point of the universal control handle, and the motion states of the lawn mower are determined by the rotational speed difference (magnitude and direction of the rotational speed) between the left drive wheel and the right drive wheel.

[0112] Next, the process of establishing the first polar radius - polar angle - voltage relationship table and the second polar radius - polar angle - voltage relationship table according to the motion states (forward, backward, acceleration, deceleration, turning) of the lawn mower that need to be achieved at each position point of the universal control handle will be further described:

[0113] Taking the walking mechanism with the rear wheels as the drive wheels and the front wheels as two passive universal wheels as an example, as Figures 3 - 5 shown, it is a schematic diagram of the turning analysis of the passive universal wheels (front wheels), left drive wheel (left rear wheel), and right drive wheel (right rear wheel) of the walking mechanism of the lawn mower in different motion states. Let the rotational speed of the left drive wheel be n1, the rotational speed of the right drive wheel be n2, the wheel spacing between the left drive wheel and the right drive wheel be L, the turning radius of the left drive wheel be R1, and the turning radius of the right drive wheel be R2. From this, it can be known that the rotational speed ratio of the left rear wheel to the right rear wheel n1 / n2 = 1 + L / R2. Let the rotational speed ratio of the left rear wheel to the right rear wheel be K, then K = n1 / n2 = 1 + L / R2. Let n1 and n2 be positive when the left rear wheel and the right rear wheel rotate clockwise (forward rotation), and n1 and n2 be negative when the left rear wheel and the right rear wheel rotate counterclockwise (reverse rotation).

[0114] The analysis of the traveling state of the walking mechanism is as follows:

[0115] To achieve steering, we make the left and right rear wheels form a differential. The front wheels are universal wheels, and there are several situations as analyzed below:

[0116] 1. In the case of straight - line forward movement, at this time,

[0117] K = 1, corresponding to R2 = +∞, that is, n1 = n2 > 0;

[0118] 2. In the case of turning (such as Figure 3 establishing a coordinate system):

[0119] 2.1. When the center of the turn "O" is on the right side of the right rear wheel, see Figure 3 , at this time,

[0120] The walking mechanism turns clockwise and moves forward (turns right and moves forward), and the left rear wheel has a faster speed, that is, K > 1;

[0121] 2.2. When the center of the turn "O" is at the contact point of the right rear wheel with the ground, at this time,

[0122] The traveling mechanism turns clockwise and moves forward (right turn forward), R2 = 0, R1 = L, corresponding to K = +∞, that is, n2 = 0, n1 > 0;

[0123] 2.3. The center of the turn "O" is between the right rear wheel and the left rear wheel, as shown in Figure 4 , at this time,

[0124] The traveling mechanism turns clockwise and moves forward (right turn forward), R2 < 0, and L / R2 < -1, that is, K < 0, n1 > 0, n2 < 0;

[0125] 2.4. The center of the turn "O" is on the left side of the left rear wheel, as shown in Figure 5 , at this time,

[0126] The traveling mechanism turns counterclockwise. In this case, it is a reverse left turn, and the two rear wheels reverse, that is: K > 0, n1 < n2 < 0;

[0127] 3. The situation when moving straight backward. At this time,

[0128] K = 1, corresponding to R2 = +∞, and the two rear wheels reverse, that is, n1 = n2 < 0.

[0129] Through the above analysis, it can be seen that to enable the lawn mower to achieve different motion states, it is necessary to separately control the speeds and rotation directions of the left and right drive wheels of the traveling mechanism. To control the speeds and rotation directions of the left and right drive wheels, it is necessary to first establish the relationship between the drive wheel speed and voltage, so that the target speed (including the rotation direction) of the drive wheel corresponds one-to-one with the voltage signal. Then, based on the relationship between the drive wheel speed and voltage, and the positions of the universal control handle at various points, establish the first radius - polar angle - voltage relationship table and the second radius - polar angle - voltage relationship table. In this way, the corresponding relationship between the positions of the universal control handle at various points and the motion states (forward, backward, acceleration, deceleration, turning) of the lawn mower to be achieved can be established.

[0130] As Figure 6 shown, the embodiment of the present invention also provides a lawn mower motion control system. This system is applied to a riding lawn mower, and the riding lawn mower includes a universal control handle, a traveling mechanism, and a traveling drive mechanism. Among them,

[0131] The traveling mechanism includes a passive universal wheel, a left drive wheel, and a right drive wheel arranged at the bottom of the riding lawn mower;

[0132] The traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel, and a right drive motor drivingly connected to the right drive wheel;

[0133] The lawn mower motion control system includes:

[0134] The handle position vector information acquisition module 201 is configured to acquire the current position vector information of the universal operating handle in response to an operation on the universal operating handle;

[0135] The voltage signal generation module 202 generates a first voltage signal and a second voltage signal based on the current position vector information of the universal operating handle;

[0136] The drive motor control module 203 is configured to control the rotational speed and rotation direction of the left drive motor based on the first voltage signal, and control the rotational speed and rotation direction of the right drive motor based on the second voltage signal, so as to control the rotational speed and rotation direction of the left drive wheel and the right drive wheel.

[0137] In one embodiment, the handle position vector information acquisition module 201 includes:

[0138] The handle position information acquisition unit is configured to acquire the current position information of the universal operating handle in a rectangular coordinate system;

[0139] The position information conversion unit is configured to perform a rectangular coordinate system - polar coordinate system conversion on the current position information to obtain the current position vector information of the universal operating handle in the polar coordinate system.

[0140] In one embodiment, the current position vector information includes polar radius information and polar angle information. The polar radius information is used to represent the moving distance of the universal operating handle relative to the initial position, and the polar angle information is used to represent the rotation angle of the universal operating handle relative to the reference direction.

[0141] In one embodiment, the voltage signal generation module 202 includes:

[0142] The first voltage signal generation unit is configured to look up a first voltage value that matches the polar radius information and the polar angle information in a pre - constructed first polar radius - polar angle - voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generate a first voltage signal based on the first voltage value; and

[0143] The second voltage signal generation unit is configured to look up a second voltage value that matches the polar radius information and the polar angle information in a pre - constructed second polar radius - polar angle - voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generate a second voltage signal based on the second voltage value.

[0144] In one embodiment, the drive motor control module 203 includes:

[0145] The first motor target state determination unit determines the target rotational speed and rotation direction of the left drive motor based on the first voltage signal and a pre - constructed drive wheel rotational speed - voltage relationship formula;

[0146] The first motor control unit controls the drive current of the left drive motor so that the left drive motor operates at a target rotational speed and in a rotational direction.

[0147] The second motor target state determination unit determines the target rotational speed and rotational direction of the right drive motor based on the second voltage signal and a pre-established relationship between the rotational speed of the drive wheel and the voltage.

[0148] The second motor control unit controls the drive current of the right drive motor so that the right drive motor operates at a target rotational speed and in a rotational direction.

[0149] The working principle and beneficial effects of the lawn mower motion control system in the above embodiments are the same as those of the lawn mower motion control method in the above embodiments, and will not be elaborated here.

[0150] As Figure 7 shown, an embodiment of the present invention further provides a lawn mower motion control device 3, including a memory 301, a processor 302, and a computer program 303 stored in the memory 301 and executable on the processor 302. When the processor 302 executes the computer program 303, the lawn mower motion control method in any of the above embodiments is implemented.

[0151] An embodiment of the present invention further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program. When the computer program is executed by a processor, the lawn mower motion control method in any of the above embodiments is implemented.

[0152] An embodiment of the present invention further provides a riding lawn mower, including a universal steering handle, a traveling mechanism, and a traveling drive mechanism. Among them,

[0153] The traveling mechanism includes a passive universal wheel, a left drive wheel, and a right drive wheel provided at the bottom of the riding lawn mower;

[0154] The traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel and a right drive motor drivingly connected to the right drive wheel;

[0155] The riding lawn mower further includes the lawn mower motion control device in the above embodiments.

[0156] In the embodiments provided in this application, it should be understood that the disclosed methods and systems can be implemented in other ways. The system embodiments described above are merely illustrative. For example, the division of modules is only a logical function division. In actual implementation, there may be other division methods. For example, multiple modules or components can be combined, or can be integrated into another system, or some features can be ignored, or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed with each other can be through some interfaces, and the indirect coupling or communication connection of devices or modules can be electrical, mechanical, or other forms.

[0157] In addition, each functional module in the embodiments of the present invention can be all integrated in a processor, or each module can be separately used as a device alone, or two or more modules can be integrated in a device; each functional module in the embodiments of the present invention can be implemented in the form of hardware, or in the form of a combination of hardware and software functional units.

[0158] Those of ordinary skill in the art can understand that all or part of the steps for implementing the above method embodiments can be completed through program instructions and related hardware. The foregoing program instructions can be stored in a computer-readable storage medium. When the program instructions are executed, the steps including the above method embodiments are executed; and the foregoing storage media include: various media such as removable storage devices, read-only memory (ROM), magnetic disks, or optical discs that can store program codes.

[0159] It should be understood that in this application, if the terms "system", "device", "unit" and / or "module" are used, they are only a method for distinguishing different components, elements, parts, portions or assemblies at different levels. However, if other words can achieve the same purpose, then the term can be replaced by other expressions.

[0160] As shown in this application and the claims, unless the context clearly indicates an exceptional situation, words such as "a", "one", "a kind of" and / or "the" are not specifically singular, but can also include the plural. Generally speaking, the terms "including" and "comprising" only indicate the inclusion of the clearly identified steps and elements, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements. The element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, commodity or device including the element.

[0161] Among them, in the description of the embodiments of the present application, unless otherwise specified, " / " means "or". For example, A / B may mean A or B. The "and / or" herein is merely a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B may mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present application, "a plurality of" means two or more than two.

[0162] Hereinafter, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0163] If a flowchart is used in the present application, the flowchart is used to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the operations before or after do not necessarily need to be executed precisely in sequence. On the contrary, they can be executed in reverse order or simultaneously. At the same time, other operations can also be added to these processes, or one or several operations can be removed from these processes.

[0164] The above has introduced in detail a lawn mower motion control method, system, device, storage medium and riding lawn mower provided by the present invention. The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A lawn mower motion control method, which is applied to a riding lawn mower, characterized in that: the riding lawn mower includes a universal steering handle, a traveling mechanism and a traveling drive mechanism, wherein, the traveling mechanism includes a passive universal wheel, a left drive wheel and a right drive wheel arranged at the bottom of the riding lawn mower; the traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel, and a right drive motor drivingly connected to the right drive wheel; the lawn mower motion control method includes the following steps: responding to an operation on the universal steering handle, obtaining the current position vector information of the universal steering handle; generating a first voltage signal and a second voltage signal based on the current position vector information of the universal steering handle; controlling the rotation speed and rotation direction of the left drive motor based on the first voltage signal, and controlling the rotation speed and rotation direction of the right drive motor based on the second voltage signal, so as to control the rotation speed and rotation direction of the left drive wheel and the right drive wheel; the current position vector information includes polar radius information and polar angle information, the polar radius information is used to represent the moving distance of the universal steering handle relative to the initial position, and the polar angle information is used to represent the rotation angle of the universal steering handle relative to the reference direction; the generating a first voltage signal and a second voltage signal based on the current position vector information of the universal steering handle includes: looking up a first voltage value matching the polar radius information and the polar angle information in a pre-constructed first polar radius-polar angle-voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generating the first voltage signal based on the first voltage value; and looking up a second voltage value matching the polar radius information and the polar angle information in a pre-constructed second polar radius-polar angle-voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generating the second voltage signal based on the second voltage value.

2. The lawn mower motion control method according to claim 1, characterized in that, the obtaining the current position vector information of the universal steering handle includes: obtaining the current position information of the universal steering handle in a rectangular coordinate system; performing a rectangular coordinate system - polar coordinate system conversion on the current position information to obtain the current position vector information of the universal steering handle in the polar coordinate system.

3. The lawn mower motion control method according to claim 1 or 2, characterized in that: the controlling the rotation speed and rotation direction of the left drive motor based on the first voltage signal includes: determining the target rotation speed and rotation direction of the left drive motor based on the first voltage signal and a pre-constructed driving wheel rotation speed - voltage relationship formula; controlling the drive current of the left drive motor so that the left drive motor operates at the target rotation speed and rotation direction; the controlling the rotation speed and rotation direction of the right drive motor based on the second voltage signal includes: determining the target rotation speed and rotation direction of the right drive motor based on the second voltage signal and a pre-constructed driving wheel rotation speed - voltage relationship formula; Control the drive current of the right drive motor so that the right drive motor operates at the target rotational speed and in the rotational direction.

4. A lawn mower motion control system applied to a riding lawn mower, characterized in that: The riding lawn mower includes a universal steering handle, a traveling mechanism, and a traveling drive mechanism, where the traveling mechanism includes a passive universal wheel, a left drive wheel, and a right drive wheel provided at the bottom of the riding lawn mower; the traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel and a right drive motor drivingly connected to the right drive wheel; the lawn mower motion control system includes: a handle position vector information acquisition module for acquiring the current position vector information of the universal steering handle in response to an operation on the universal steering handle; a voltage signal generation module for generating a first voltage signal and a second voltage signal based on the current position vector information of the universal steering handle; a drive motor control module for controlling the rotational speed and rotational direction of the left drive motor based on the first voltage signal and controlling the rotational speed and rotational direction of the right drive motor based on the second voltage signal to control the rotational speeds and rotational directions of the left drive wheel and the right drive wheel; the current position vector information includes polar radius information and polar angle information, the polar radius information is used to represent the moving distance of the universal steering handle relative to the initial position, and the polar angle information is used to represent the rotational angle of the universal steering handle relative to the reference direction; the voltage signal generation module includes: a first voltage signal generation unit for looking up a first voltage value matching the polar radius information and the polar angle information in a pre-constructed first polar radius - polar angle - voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generating the first voltage signal based on the first voltage value; and a second voltage signal generation unit for looking up a second voltage value matching the polar radius information and the polar angle information in a pre-constructed second polar radius - polar angle - voltage relationship table based on the polar radius information and the polar angle information of the current position vector information, and generating the second voltage signal based on the second voltage value.

5. The lawn mower motion control system according to claim 4, characterized in that the handle position vector information acquisition module includes: a handle position information acquisition unit for acquiring the current position information of the universal steering handle in a rectangular coordinate system; a position information conversion unit for performing a rectangular coordinate system - polar coordinate system conversion on the current position information to obtain the current position vector information of the universal steering handle in the polar coordinate system.

6. A lawn mower motion control device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: when the processor executes the computer program, it implements the lawn mower motion control method according to any one of claims 1 - 3.

7. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, it implements the lawn mower motion control method according to any one of claims 1-3.

8. A riding lawn mower, characterized in that it includes a universal steering handle, a traveling mechanism and a traveling drive mechanism, wherein the traveling mechanism includes a passive universal wheel, a left drive wheel and a right drive wheel arranged at the bottom of the riding lawn mower; the traveling drive mechanism includes a left drive motor drivingly connected to the left drive wheel and a right drive motor drivingly connected to the right drive wheel; the riding lawn mower further includes the lawn mower motion control device according to claim 6.

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