A walking control method for a lawn mowing robot

Abstract

The present invention discloses a walking control method for a lawn mowing robot, which includes the following steps: Step 1: Start the machine. When the machine receives the first instruction, it executes the first predetermined action and then executes the first instruction. Step 2: When the machine receives a new instruction after receiving the first instruction, it determines whether the new instruction is a reverse instruction or a non-reverse instruction. When the new instruction is a reverse instruction, the machine enters Step 3. When the new instruction is a non-reverse instruction, the machine directly executes the new instruction. When the direction of the new instruction is opposite to that of the first instruction, the new instruction is a reverse instruction; otherwise, it is a non-reverse instruction. Step 3: The machine first executes the second predetermined action and then executes the new instruction. The second predetermined action has the same direction as the first predetermined action. The present invention can control the rotation direction when the universal wheel makes a 180-degree turn, that is, it can reduce the risk of grass entanglement.

Description

Technical Field

[0001] The present invention belongs to the technical field of lawn mowers, and particularly relates to a walking control method for a lawn mowing robot. Background Art

[0002] A lawn mowing robot is an intelligent robot that can move autonomously continuously and in real time on roads and outdoors. As a type of self-propelled device, the intelligent lawn mowing robot is suitable for clearing vegetation in plots such as hills, terraced fields, plains, and weeds within lawns. Its operation is simple and the work efficiency is high.

[0003] The front wheels of common lawn mowing robots can use universal wheels, and the rear wheels are drive wheels. The universal wheel is a so-called swivel caster, and its structure allows 360-degree horizontal rotation. When the robot turns, it turns through the rear wheels, and the front wheels can rotate automatically according to the turning direction. In actual work, such a structure makes the universal wheel prone to the risk of grass entanglement, especially when the universal wheel rotates 360 degrees. For example Figure 1 in, when the machine receives instructions to turn left, reverse, and then move forward during the forward movement, when switching from forward to turning left, the universal wheel rotates counterclockwise, and when switching from turning left to reversing, the universal wheel continues to rotate counterclockwise (i.e., rotates 180 degrees counterclockwise). Finally, when switching from reversing to forward, assume that it rotates counterclockwise again (i.e., rotates 180 degrees counterclockwise again). At this time, the rotation direction of the universal wheel is out of control. Looking at the whole process, the universal wheel has rotated 360 degrees. Similarly, in Figure 3 the universal wheel rotates 360 degrees clockwise. Combining with Figure 5 again, when the machine receives instructions to move forward, turn right, and then turn left during the left-turning process, when switching from left-turning to moving forward, the universal wheel rotates clockwise, and when switching from moving forward to turning right, it then rotates clockwise (i.e., rotates 180 degrees clockwise). Finally, when switching from turning right to left-turning, assume that it rotates clockwise again (i.e., rotates 180 degrees clockwise again). Looking at the whole process, the universal wheel has rotated 360 degrees. Similarly, in Figure 7 the universal wheel rotates 360 degrees counterclockwise. Therefore, when the machine changes its running direction, the universal wheel is prone to the risk of grass entanglement when it rotates. The larger the rotation angle, the greater the risk and degree of grass entanglement, which affects or even damages the normal operation of the machine. Summary of the Invention

[0004] The present invention provides a walking control method for a lawn mowing robot, which can reduce or even avoid the risk of grass entanglement of the universal wheel to a certain extent.

[0005] The technical solution to achieve the above object is as follows:

[0006] A walking control method for a lawn mowing robot includes the following steps:

[0007] Step 1: Start the machine. When the machine receives the first instruction, it performs the first predetermined action and then executes the first instruction.

[0008] Step 2: When the machine receives a new instruction after receiving the first instruction, determine whether the new instruction is a reverse instruction or a non-reverse instruction. When the new instruction is a reverse instruction, the machine enters Step 3. When the new instruction is a non-reverse instruction, the machine directly executes the new instruction. When the new instruction is in the opposite direction to the first instruction, then the new instruction is a reverse instruction; otherwise, it is a non-reverse instruction.

[0009] Step 3: The machine first performs the second predetermined action and then executes the new instruction.

[0010] The second predetermined action is in the same direction as the first predetermined action.

[0011] Further, when there is a non-reverse instruction between the first predetermined action and the second predetermined action, the second predetermined action is in the same direction as the last non-reverse instruction.

[0012] When there is no non-reverse instruction between the first predetermined action and the second predetermined action, the second predetermined action is in the same direction as the first predetermined action.

[0013] Further, the first instruction, the new instruction, the reverse instruction, and the non-reverse instruction include turning left, turning right, moving forward, and moving backward.

[0014] Further, the first instruction only includes a forward instruction or a backward instruction.

[0015] Further, when the first predetermined action and the second predetermined action are turning left or turning right, the turning amplitude does not exceed 5°.

[0016] Further, the instruction is an instruction sent manually or an instruction generated by the internal control program of the machine.

[0017] Further, the universal wheel is the front wheel of the machine.

[0018] Further, the machine is an intelligent lawn mower.

[0019] Further, after the machine executes the new instruction, it performs a compensation action, and the compensation action is in the opposite direction to the second predetermined action and has the same amplitude.

[0020] Compared with the prior art, the advantages of the present invention include:

[0021] The control method of the present invention can set a predetermined action before the start of a new instruction action to control the swinging direction of the caster wheel during the execution of the instruction by the remote-controlled lawn mower, avoid the 360° rotation of the caster wheel, reduce the situation of grass entanglement, and can control the rotation direction of the caster wheel during a 180° turn through the above method, that is, the risk of grass entanglement can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the caster wheel turning when the prior art lawn mower receives left turn, reverse, and forward instructions in the forward state.

[0023] Figure 2 It is a schematic diagram of the caster wheel turning when the lawn mower of the present invention receives left turn, reverse, and forward instructions in the forward state.

[0024] Figure 3 It is a schematic diagram of the caster wheel turning when the prior art lawn mower receives right turn, reverse, and forward instructions in the forward state.

[0025] Figure 4 It is a schematic diagram of the caster wheel turning when the lawn mower of the present invention receives right turn, reverse, and forward instructions in the forward state.

[0026] Figure 5 It is a schematic diagram of the caster wheel turning when the prior art lawn mower receives forward, right turn, and left turn instructions in the left turn state.

[0027] Figure 6 It is a schematic diagram of the caster wheel turning when the lawn mower of the present invention receives forward, right turn, and left turn instructions in the left turn state.

[0028] Figure 7 It is a schematic diagram of the caster wheel turning when the prior art lawn mower receives reverse, right turn, and left turn instructions in the left turn state.

[0029] Figure 8 It is a schematic diagram of the caster wheel turning when the lawn mower of the present invention receives reverse, right turn, and left turn instructions in the left turn state. DETAILED DESCRIPTION OF THE INVENTION

[0030] The present invention is a walking control method for a lawn mowing robot, which is applicable to machines such as self-propelled devices that need to operate on grasslands and lawns and have drive wheels and caster wheels. The following takes the lawn mowing robot as an example to illustrate the solution.

[0031] A walking control method for a lawn mowing robot includes the following steps:

[0032] Step 1: Start the lawn mowing robot. When receiving an instruction for a forward or reverse action for the first time, the lawn mowing robot first executes a first predetermined action and then moves forward or backward according to the instruction;

[0033] Step 2: During the operation of the lawn mower robot, when the latest instruction that is completely opposite to the current instruction is received, the lawn mower robot first executes the second predetermined action and then executes the latest instruction action. The first predetermined action and the second predetermined action are one of turning left, turning right, moving forward, and moving backward. If the lawn mower robot has not turned left or right during the operation, the second predetermined action has the same direction as the first predetermined action. This situation corresponds to the robot executing the forward or backward instruction since startup. At startup, it is impossible to determine the direction of the universal wheel. Therefore, a first predetermined action (such as turning left) is executed in advance, so that the steering of the universal wheel can be controlled when the robot executes the instruction. When the latest instruction that is completely opposite to the current instruction is received later, the lawn mower robot first executes the second predetermined action and then executes the latest instruction, which also makes the steering of the universal wheel controllable. The rotation directions of the universal wheel are opposite twice, and it only rotates back and forth on one side. If the lawn mower robot has turned left or right during the operation, the direction of the second predetermined action is the same as the direction of the last turning action before the latest instruction.

[0034] Specifically, the current instruction and the latest instruction include turning left, turning right, moving forward, and moving backward.

[0035] Specifically, when the first predetermined action and the second predetermined action are turning left or turning right, the turning amplitude does not exceed 5°.

[0036] Specifically, the instructions are instructions sent manually (for example, sent through a remote control device) or instructions generated by an internal control program of the robot (for example, motion instructions generated by a lawn mowing robot according to a traversal route and an obstacle avoidance route).

[0037] Specifically, the universal wheel is the front wheel of the robot.

[0038] Specifically, in order to reduce the deviation of the running route of the lawn mower robot due to the predetermined action, a compensation action is performed after the lawn mower robot executes the latest instruction. The compensation action is opposite to the second predetermined action in direction and has the same amplitude, so that the lawn mower robot returns to the running trajectory before executing the predetermined action and eliminates the deviation.

[0039] Through this control method, a predetermined action can be set before the latest command action starts, which is used to control the swing direction of the universal wheel reset when the remote control lawn mower executes the command, avoiding the 360° rotation of the universal wheel and reducing the situation and degree of grass entanglement. Figure 1 , 3, 5, 7), it is found that when the front and rear states of the caster wheel differ by 180 degrees, the rotation direction of the caster wheel is random (related to the force at that time), mainly in two working conditions: forward to reverse, left turn to right turn. When the front and rear states of the caster wheel change, it always chooses to rotate in the direction with an angle change less than 180 degrees. By the above method, the rotation direction of the caster wheel during a 180-degree turn can be controlled, that is, the risk of grass entanglement can be reduced. Four specific embodiments are given below.

[0040] Embodiment 1

[0041] This embodiment corresponds to Figure 1 the situation of the prior art described, combined with Figure 2 , the front wheel of the lawn mowing robot is a caster wheel, and the rear wheel is a driving wheel. When the lawn mowing robot receives a left turn instruction in the forward state, the driving wheel turns, and the robot turns left. At this time, the caster wheel rotates counterclockwise. Then when it receives a reverse instruction, the caster wheel continues to rotate counterclockwise. Compared with the forward state, the caster wheel rotates 180 degrees counterclockwise. At this time, when receiving an "advance" instruction opposite to the current "reverse" instruction, the robot first executes a second predetermined action of turning left, for example, it can turn left by 4°. At this time, the caster wheel will rotate clockwise by 4°. Then it executes the forward instruction. On the basis of executing the second predetermined action of turning left by 4°, the caster wheel will continue to rotate clockwise until it enters the forward state. Through this embodiment, it can be found that when receiving an advance instruction in the reverse state, due to the execution of the second predetermined action, the steering of the caster wheel becomes controllable (the caster wheel will choose to rotate in the direction with an angle change less than 180 degrees). Therefore, considering the whole process, it can be found that the caster wheel rotates 180 degrees counterclockwise in the front and 180 degrees clockwise in the back, only rotating back and forth on one side, effectively avoiding the occurrence of the situation of rotating 360 degrees. Therefore, the risk of grass entanglement is greatly reduced.

[0042] Embodiment 2

[0043] This embodiment corresponds to Figure 3 the situation of the prior art described, combined with Figure 4 , the difference between this embodiment and Embodiment 1 is that the lawn mowing robot receives a right turn instruction in the forward state. Therefore, the second predetermined action is set to turn right. It can be found throughout the process that the caster wheel rotates 180 degrees clockwise in the front and 180 degrees counterclockwise in the back, also only rotating back and forth on one side, effectively avoiding the occurrence of the situation of rotating 360 degrees.

[0044] Embodiment 3

[0045] This embodiment corresponds to Figure 5 the situation of the prior art described, combined with Figure 6, the front wheels of the lawn mowing robot are omnidirectional wheels, and the rear wheels are drive wheels. When the lawn mowing robot receives a forward command in the left-turn state, the drive wheels turn and the robot moves forward. At this time, the omnidirectional wheels rotate clockwise. Then when it receives a right-turn command, the omnidirectional wheels continue to rotate clockwise. Compared with the left-turn state, the omnidirectional wheels rotate 180 degrees clockwise. At this time, when it receives a "left-turn" command opposite to the current "right-turn" command, the robot first executes a second predetermined forward action, for example, it can move forward slightly by 2 - 5 cm (control the rotation degree of the omnidirectional wheels within a predetermined degree). At this time, the omnidirectional wheels will rotate counterclockwise, and then execute the left-turn command. Based on the execution of the second predetermined forward action, the omnidirectional wheels will continue to rotate counterclockwise until it enters the left-turn state. Through this embodiment, it can be found that when receiving a left-turn command in the right-turn state, due to the execution of the second predetermined action, the turning of the omnidirectional wheels becomes controllable (the omnidirectional wheels will choose to rotate in a direction with an angle change less than 180 degrees). Therefore, considering the whole process, it can be found that the omnidirectional wheels rotate 180 degrees clockwise in the front and 180 degrees counterclockwise in the back, only rotating back and forth on one side, effectively avoiding the occurrence of the situation of rotating 360 degrees. Therefore, the risk of grass entanglement is greatly reduced.

[0046] Embodiment 4

[0047] This embodiment corresponds to Figure 7 the situation of the prior art described, combined with Figure 8 , the difference between this embodiment and Embodiment 3 is that the lawn mowing robot receives a left-turn command in the right-turn state. Therefore, the second predetermined action is set to reverse. It can be found throughout the process that the omnidirectional wheels rotate 180 degrees counterclockwise in the front and 180 degrees clockwise in the back. Similarly, it only rotates back and forth on one side, effectively avoiding the occurrence of the situation of rotating 360 degrees.

[0048] The above embodiments all describe the control method by taking the steering actions existing between forward and backward of the machine as examples. Based on the above description, it can also be understood that when there are actions such as forward and backward between left-turn and right-turn of the machine, the machine can also generate corresponding predetermined actions according to the actual commands to avoid grass entanglement of the omnidirectional wheels.

[0049] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A walking control method for a lawn mowing robot, characterized in that, Including the following steps: Step 1: Start the machine. When the machine receives the first instruction, it performs a first predetermined action and then executes the first instruction. Step 2: When the machine receives a new instruction after receiving the first instruction, determine whether the new instruction is a reverse instruction or a non-reverse instruction. When the new instruction is a reverse instruction, the machine proceeds to Step 3. When the new instruction is a non-reverse instruction, the machine directly executes the new instruction. When the new instruction is in the opposite direction to the first instruction, then the new instruction is a reverse instruction; otherwise, it is a non-reverse instruction. Step 3: The machine first performs a second predetermined action and then executes the new instruction. When there is a non-reverse instruction between the first predetermined action and the second predetermined action, the second predetermined action is in the same direction as the last non-reverse instruction. When there is no non-reverse instruction between the first predetermined action and the second predetermined action, the second predetermined action is in the same direction as the first predetermined action. The first instruction, new instruction, reverse instruction, non-reverse instruction, first predetermined action, and second predetermined action include turning left, turning right, moving forward, and moving backward. The lawn mowing robot includes omnidirectional wheels.

2. The walking control method for a lawn mowing robot according to claim 1, characterized in that: The first instruction only includes a forward instruction or a backward instruction.

3. The walking control method for a lawn mowing robot according to claim 1, wherein When the first predetermined action and the second predetermined action are turning left or turning right, the turning amplitude does not exceed 5°.

4. The walking control method for a lawn mowing robot according to claim 1, wherein The instruction is an instruction sent manually or an instruction generated by the internal control program of the machine.

5. The walking control method for a lawn mowing robot according to claim 1, characterized in that, The omnidirectional wheels are the front wheels of the machine.

6. The walking control method for a lawn mowing robot according to claim 1, characterized in that, The machine is an intelligent lawn mower.

7. The walking control method for a lawn mowing robot according to any one of claims 1-6, characterized in that, After the machine executes the new instruction, a compensation action is performed. The compensation action is in the opposite direction to the second predetermined action and has the same amplitude.

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