Work robot

Abstract

To provide a technique that improves the usability of a work robot.SOLUTION: A work robot comprises: a robot main body; a movement unit for moving the robot main body; a work unit supported by the robot main body; a height adjustment unit for changing the height of the work unit relative to the robot main body; and a control unit. The control unit can execute autonomous operations including work processing for performing a work by the work unit while moving the robot main body via the movement unit, and height adjustment processing for adjusting the height of the work unit relative to the robot unit in multiple stages by the height adjustment unit. The work robot can be switched between a first state in which the control unit executes the height adjustment processing in autonomous operation, and a second state in which the control unit does not execute the height adjustment processing in autonomous operation.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a working robot. [Background technology]

[0002] Patent Document 1 discloses a working robot including a robot body, a moving unit that moves the robot body, a working unit supported by the robot body, a height adjustment unit that changes the height of the working unit relative to the robot body, and a control unit. The control unit is configured to be capable of performing autonomous operation including a task process in which the working unit performs a task while moving the robot body using the moving unit. A user can adjust the height of the working unit relative to the robot body by manually operating the height adjustment unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Republished Patent No. 2017 / 051663 Summary of the Invention [Problem to be solved by the invention]

[0004] The working robot of Patent Document 1 cannot adjust the height of the working part while performing autonomous driving unless the user manually operates the working robot. This may cause inconvenience such as the user having to monitor the progress of the work performed by the working robot in order to adjust the height of the working part. As a result, the usability of the working robot may deteriorate. This specification provides a technology capable of improving the usability of the working robot. [Means for solving the problem]

[0005] The working robot disclosed in this specification includes a robot body, a movement unit that moves the robot body, a working unit supported by the robot body, a height adjustment unit that changes the height of the working unit relative to the robot body, and a control unit. The control unit is configured to be capable of executing autonomous driving including a work process in which the working unit performs a work while moving the robot body by the movement unit, and a height adjustment process in which the height of the working unit relative to the robot body is adjusted in multiple stages by the height adjustment unit. The working robot is switchable between a first state in which the control unit executes the height adjustment process during the autonomous driving, and a second state in which the control unit does not execute the height adjustment process during the autonomous driving.

[0006] According to the above configuration, the work robot can adjust the height of the working unit without the need for manual operation by the user by performing a height adjustment process while performing autonomous driving. This eliminates the need for the user to monitor the progress of the work performed by the work robot, thereby improving the usability of the work robot. However, in some cases, it may be desirable not to perform the height adjustment process. For example, this is the case when the user wishes to keep the height of the working unit constant throughout the autonomous driving. Furthermore, according to the above configuration, the state of the work robot can be switched between a first state in which the height adjustment process is performed while performing autonomous driving, and a second state in which the height adjustment process is not performed while performing autonomous driving. This allows the user to select whether or not to perform the height adjustment process while performing autonomous driving, thereby further improving the usability of the work robot.

[0007] Another working robot disclosed in this specification includes a robot body, a movement unit that moves the robot body, a working unit supported by the robot body, a height adjustment unit that changes the height of the working unit relative to the robot body, an input unit that accepts input from a user, and a control unit. The control unit is configured to be capable of executing autonomous operation including a work process in which the working unit performs a work while moving the robot body by the movement unit, and a height adjustment process in which the height of the working unit relative to the robot body is adjusted in multiple stages by the height adjustment unit. The control unit executes the height adjustment process based on an input value input to the input unit.

[0008] According to the above configuration, the work robot can adjust the height of the working unit without the need for manual operation by the user by executing a height adjustment process while performing autonomous operation. This eliminates the need for the user to monitor the progress of work performed by the work robot, thereby improving the usability of the work robot. Furthermore, according to the above configuration, the height adjustment process is executed based on an input value entered by the user into the input unit. This allows the height adjustment process to be tailored to the environment in which the user uses the work robot and the work content that the user wants the work robot to perform, thereby further improving the usability of the work robot. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing an example of use of the robot lawnmower 2 according to the first embodiment. FIG. [Diagram 2] FIG. 2 is a left side view of the robotic lawnmower 2 according to the first embodiment. [Diagram 3] FIG. 2 is a rear view of the robotic lawnmower 2 according to the first embodiment. [Figure 4] 1 is a schematic configuration diagram of a robotic lawnmower 2 according to a first embodiment. [Diagram 5] 2 is a diagram showing a schematic configuration of the vicinity of a collision detection sensor 66 of the robot lawnmower 2 according to the first embodiment. FIG. [Figure 6]2 is a diagram showing a schematic configuration of the vicinity of a lifting detection sensor 68 of the robotic lawnmower 2 according to the first embodiment. FIG. [Figure 7] 10 is a flowchart of autonomous driving executed by a control unit 8 of the robotic lawnmower 2 according to the first embodiment when an automatic height adjustment function is on. [Figure 8] 3 is a diagram showing a schematic diagram of a threshold value table TT stored in a memory 36 of a control unit 8 of the robotic lawnmower 2 according to the first embodiment. FIG. [Figure 9] 10 is a flowchart of autonomous driving executed by the control unit 8 of the robotic lawnmower 2 according to the first embodiment when the automatic height adjustment function is turned off. [Figure 10] 4 is a flowchart of a process executed by a control unit 8 while the robotic lawnmower 2 according to the first embodiment is operating autonomously. [Figure 11] 10 is a flowchart of a process executed by a control unit 8 while a robotic lawnmower 202 according to a second embodiment is operating autonomously. [Figure 12] 10 is a flowchart of a process executed by a control unit 8 while a robotic lawnmower 302 according to a third embodiment is operating autonomously. [Figure 13] 13 is a flowchart of autonomous driving executed by a control unit 8 of a robotic lawnmower 402 according to Example 4 when an automatic height adjustment function is on. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Representative and non-limiting examples of the present invention are described in detail below with reference to the drawings. This detailed description is intended simply to provide those skilled in the art with details for implementing the preferred examples of the present invention, and is not intended to limit the scope of the present invention. Additionally, the additional features and inventions disclosed can be used separately or together with other features and inventions to provide further improved work robots.

[0011] In addition, the combinations of features and steps disclosed in the following detailed description are not essential for implementing the present invention in the broadest sense, but are specifically described only to illustrate representative embodiments of the present invention. Furthermore, the various features of the following representative embodiments and the various features described in the claims do not have to be combined in the exact manner of the embodiments described herein or in the order listed in order to provide additional and useful embodiments of the present invention.

[0012] All features described in the specification and / or claims are intended to be disclosed individually and independently of one another as limitations to the specific features described in the original disclosure and claims, apart from the configuration of features described in the examples and / or claims. Furthermore, all numerical ranges and group or aggregate descriptions are intended to disclose intermediate configurations thereof as limitations to the specific features described in the original disclosure and claims.

[0013] In one or more embodiments, the working robot may further include an input unit that receives an input from a user, and the control unit may execute the height adjustment process based on an input value input to the input unit.

[0014] According to the above configuration, the height adjustment process is executed based on the input value entered by the user into the input section, which allows the height adjustment process to be adapted to the environment in which the user uses the work robot and the work content that the user wants the work robot to perform, thereby further improving the usability of the work robot.

[0015] In one or more embodiments, the height adjustment process may include a first height adjustment process in which the height of the working unit relative to the robot body is set to an initial height, and a second height adjustment process in which the height of the working unit relative to the robot body is changed from the initial height to a target height. The input value may include at least one of the initial height and the target height.

[0016] Depending on the work content, it may be necessary to determine in advance the height of the working unit immediately after autonomous operation starts and the height of the working unit some time after autonomous operation starts. With the above configuration, it is possible to determine in advance the height of the working unit immediately after autonomous operation starts (initial height) and the height of the working unit some time after autonomous operation starts (target height). This can further improve the usability of the working robot.

[0017] In one or more embodiments, the control unit may execute the second height adjustment process in a plurality of stages so as to change the height of the working unit relative to the robot body from the initial height to the target height in a plurality of stages. After each stage of the second height adjustment process is completed, the control unit may execute the work process until a predetermined condition is satisfied, and then start the next stage of the second height adjustment process.

[0018] Depending on the type of work, it may be desirable to change the height of the working unit in multiple stages and perform work with the working unit each time the height of the working unit changes. With the above configuration, the height of the working unit can be changed in multiple stages from the initial height to the target height, and work can be performed with the working unit each time the height of the working unit changes. This can further improve the ease of use of the working robot.

[0019] In one or more embodiments, the control unit may change the height of the working unit relative to the robot body by a predetermined amount in each stage of the second height adjustment process.

[0020] According to the above configuration, the change in height of the working unit is constant at each stage of the second height adjustment process, which makes it possible to keep the load on the working unit constant during work performed each time the height of the working unit changes.

[0021] In one or more embodiments, the control unit may be configured to acquire a workspace area. The predetermined condition may include a condition based on the workspace area.

[0022] According to the above configuration, the predetermined condition (i.e., the end condition of the work process performed during each stage of the second height adjustment process) is based on the work area. Therefore, for example, if the work area is small, the work process can be completed in a short time, and if the work area is large, the work process can be performed for a long time. This allows the work by the work unit to be performed just enough for the work area every time the height of the work unit changes.

[0023] In this case, the term "workplace" refers to a place where a work robot is used, and more specifically, refers to a place where a work robot can enter and perform work. And the term "workplace area" refers to the area of ​​the work place.

[0024] In one or more embodiments, the specified condition may include the time during which the work unit performs work after each stage of the second height adjustment process is completed exceeding a work time threshold determined based on the workspace area.

[0025] According to the above configuration, when the work area is small, the work process can be completed in a short time, and when the work area is large, the work process can be performed for a long time. This allows the work by the working unit to be performed just enough relative to the work area every time the height of the working unit changes.

[0026] In one or more embodiments, the control unit may store a threshold table in which one time threshold is assigned to each of a plurality of area ranges. When the work area is acquired, the control unit may refer to the threshold table and determine the time threshold assigned to the area range to which the work area belongs as the work time threshold.

[0027] According to the above configuration, the process by which the control unit determines the time threshold value can be simplified.

[0028] In one or more embodiments, the working unit may include a cutting blade for cutting grass. The target height may be lower than the initial height. The control unit may lower the height of the working unit relative to the robot body from the initial height to the target height in the second height adjustment process.

[0029] According to the above configuration, the working robot functions as a robotic lawnmower. Grass scraps cut by the robotic lawnmower may be spread on the lawn and used as mulch (so-called grass mulch). In this case, the smaller the size of the grass scraps, the faster they will decompose, so this is effective in promoting grass growth. According to the above configuration, the working robot cuts the grass to a uniform height in multiple stages, so the size of the cut grass scraps is relatively small. As a result, when the grass scraps are used as grass mulch, the growth of the lawn can be effectively promoted.

[0030] In one or more embodiments, the input unit may include a body input unit provided on the robot body.

[0031] The work robot can also be configured to only accept input from the user via a communication terminal. However, with this configuration, if a situation arises in which user input is required and the work robot is near the user but the communication terminal is not near the user, the user may feel annoyed. According to the above configuration, the robot body of the work robot is provided with a body input unit that accepts input from the user. Therefore, if the work robot is near the user, the user can provide input to the work robot even if the communication terminal is not near the user. This can reduce the annoyance felt by the user.

[0032] In one or more embodiments, the work robot may further include a rechargeable battery that supplies power to the work robot. The autonomous driving may further include a charging process that returns the work robot to a charging station to charge the battery. In the height adjustment process, the control unit may change the height of the working unit relative to the robot body when the work robot is in the charging station. The control unit may not change the height of the working unit relative to the robot body when the work robot is not in the charging station.

[0033] There may be obstacles in places other than the charging station. For this reason, if the height of the working unit is changed when the work robot is not at the charging station, there is a risk that the obstacles will interfere with the working unit. With the above configuration, the height of the working unit is not changed when the work robot is not at the charging station, and the height of the working unit is changed only when the work robot is at the charging station. This makes it possible to prevent obstacles from interfering with the working unit.

[0034] (Example 1: Robotic lawnmower 2) As shown in FIG. 1, the working robot of this embodiment is, for example, a robotic lawnmower 2 used within a site 100 where a lawn is laid. The site 100 is provided with, for example, a house 102, a pond 104, and a road 106. Also provided within the site 100 are a charging station 110 connected to an external power source (for example, a commercial power source) and a wire 112 that defines a working area WA of the robotic lawnmower 2. The "working area WA" here is the area surrounded by the wire 112. The robotic lawnmower 2 can detect the position of the wire 112 and move autonomously so as not to deviate from the working area WA in which the robotic lawnmower 2 is located. This allows the robotic lawnmower 2 to perform lawnmowing work while moving over the lawn so as to avoid the house 102, the pond 104, and the road 106.

[0035] 2, 3, and 4, the robotic lawnmower 2 includes a robot body 4, a power supply unit 6, a control unit 8, an input operation unit 10, a communication unit 12, a display unit 14, an alarm unit 16, a moving unit 18, a working unit 20, a height adjustment unit 22, and a detection unit 24. The power supply unit 6, the control unit 8, the input operation unit 10, the communication unit 12, the display unit 14, the alarm unit 16, the moving unit 18, the working unit 20, the height adjustment unit 22, and the detection unit 24 are each supported by the robot body 4.

[0036] As shown in Fig. 2, the robot main body 4 includes a base frame 26 and a body 28 supported by the base frame 26. The body 28 is provided so as to cover the base frame 26 from above. The body 28 is supported so as to be movable in all directions relative to the base frame 26. Normally, the body 28 is held in the position shown in Fig. 2 by a spring or the like.

[0037] The power supply unit 6 shown in FIG. 4 is capable of supplying power to each unit of the robotic lawnmower 2 via a power supply circuit 38 of the control unit 8. The power supply unit 6 includes a rechargeable battery 30, such as a lithium-ion battery, and a charging interface 32 that electrically connects to the battery 30. The nominal capacity of the battery 30 is, for example, 5.0 Ah. The nominal voltage of the battery 30 is, for example, 18 V. The robotic lawnmower 2 can be docked to a charging station 110 (see FIG. 1) via the charging interface 32. When the robotic lawnmower 2 is docked to the charging station 110, the battery 30 can be charged by power supplied from the charging station 110. The charging method for the battery 30 may be wired charging. Specifically, the battery 30 may be charged in a state in which a terminal provided on the charging station 110 and a terminal provided on the charging interface 32 are connected to each other. Alternatively, the charging method for the battery 30 may be wireless charging. Specifically, the battery 30 may be charged by causing a power transmitting coil provided in the charging station 110 to generate an induced electromotive force in a power receiving coil provided in the charging interface 32.

[0038] The control unit 8 includes a processor 34, a memory 36, and a power supply circuit 38. The memory 36 includes a ROM, a RAM, and the like. The ROM stores a program for autonomously controlling the robotic lawnmower 2. The RAM temporarily stores various signals input to the control unit 8 and various data (e.g., flags) generated in the process of the processor 34 executing processing. The processor 34 is configured to control the robotic lawnmower 2 by executing processing based on the information stored in the memory 36. The memory 36 also stores settings related to the robotic lawnmower 2. The settings related to the robotic lawnmower 2 include, for example, settings related to the working time zone of the robotic lawnmower 2. The "working time zone" here refers to a time zone during which the robotic lawnmower 2 can perform work. By setting the working time zone, it is possible to prevent work from being performed during a time zone not intended by the user (e.g., at night). The settings related to the robotic lawnmower 2 also include settings related to the height adjustment of the cutting blade 46. The settings related to the height adjustment of the cutting blade 46 include an on / off setting of an automatic height adjustment function for automatically adjusting the height h (see FIG. 2) of the cutting blade 46 during autonomous driving, which will be described later. The settings related to the height adjustment of the cutting blade 46 further include settings of the initial height of the cutting blade 46, the target height of the cutting blade 46, and the area of ​​the working area WA (see FIG. 1), which are required when the automatic height adjustment function is turned on, as well as a setting of a fixed height of the cutting blade 46, which is required when the automatic height adjustment function is turned off.

[0039] The input operation unit 10 is provided on the outer surface of the body 28 (see FIG. 2), and includes switches and the like that can be operated by the user. The user can perform various input operations related to the robotic lawnmower 2 via the input operation unit 10. The "input operations" referred to here include, for example, operations for switching the main power supply of the robotic lawnmower 2 on / off, operations for issuing instructions to the robotic lawnmower 2, and operations for changing settings related to the robotic lawnmower 2.

[0040] The communication unit 12 is an interface for connecting to the Internet, for example, via a base station (not shown) for mobile communications (3G, 4G, 5G, etc.) or a router (not shown) installed in the house 102. The control unit 8 can perform wireless communication with a communication terminal (e.g., a smartphone) owned by the user via the communication unit 12. This allows the control unit 8 to notify the communication terminal owned by the user that an abnormality has occurred in the robotic lawnmower 2, for example. The user can also perform various input operations related to the robotic lawnmower 2 via the communication terminal, in the same way as with the input operation unit 10.

[0041] The display unit 14 is provided on the outer surface of the body 28 (see FIG. 2). The display unit 14 includes, for example, a display (not shown) that displays characters and images, and a light source device that displays the status of the robotic lawnmower 2 by the chromaticity and blinking pattern of light. The "status of the robotic lawnmower 2" here includes, for example, a state in which the battery 30 is charging, or a state in which an abnormality has occurred in the robotic lawnmower 2.

[0042] The warning sound unit 16 includes, for example, a buzzer (not shown). The warning sound unit 16 can notify the user that an abnormality has occurred in the robotic lawnmower 2 by emitting a sound.

[0043] The moving unit 18 includes a pair of casters 40L, 40R, a pair of drive wheels 42L, 42R, and a pair of moving motors 44L, 44R. The moving motors 44L, 44R are, for example, brushless DC motors. The drive wheels 42L, 42R are connected to the output shafts (not shown) of the moving motors 44L, 44R, respectively. As shown in FIG. 2 and FIG. 3, the robotic lawnmower 2 is placed on the ground G with the casters 40L, 40R and the drive wheels 42L, 42R in contact with the ground G. The moving unit 18 can move the robotic lawnmower 2 forward, backward, and turn by operating the moving motors 44L, 44R (see FIG. 4) to rotate the drive wheels 42L, 42R. In this embodiment, the direction perpendicular to the ground G, that is, the direction from the ground G toward the robot body 4 is the upward direction, and the direction from the robot body 4 toward the ground G is the downward direction. The direction perpendicular to the up-down direction, from drive wheel 42R to drive wheel 42L, is defined as the left direction, and the direction from drive wheel 42L to drive wheel 42R is defined as the right direction. The direction perpendicular to the up-down direction and the left-right direction, from drive wheels 42L, 42R to casters 40L, 40R is defined as the front direction, and the direction from casters 40L, 40R to drive wheels 42L, 42R is defined as the rear direction.

[0044] As shown in FIG. 2, the working unit 20 includes a cutting blade 46 and a work motor 48. The cutting blade 46 is a rotary blade formed in a substantially circular disk shape. The work motor 48 is, for example, a brushless DC motor. The work motor 48 is disposed in a state in which an output shaft 50 is inclined from front to rear as it goes from top to bottom. The cutting blade 46 is connected to the output shaft 50 of the work motor 48. The working unit 20 can cut the grass by operating the work motor 48 to rotate the cutting blade 46.

[0045] The height adjustment unit 22 includes a height adjustment mechanism 52 and a height adjustment motor 54. The height adjustment mechanism 52 includes an outer cylinder 58 having a female thread 56 and an inner cylinder 62 having a male thread 60. The male thread 60 of the inner cylinder 62 is screwed into the female thread 56 of the outer cylinder 58. The outer cylinder 58 is supported so as to be immovable in the vertical direction relative to the base frame 26 and rotatable about an axis along the vertical direction relative to the base frame 26. The inner cylinder 62 is supported so as to be movable in the vertical direction relative to the base frame 26 and to be imrotatable relative to the base frame 26. The working unit 20 is fixed to the inner cylinder 62. The height adjustment motor 54 is, for example, a brushless DC motor. An output shaft (not shown) of the height adjustment motor 54 is connected to the outer cylinder 58 via a gear or the like. The height adjustment unit 22 can change the vertical position of the inner cylinder 62 by operating the height adjustment motor 54 to rotate the outer cylinder 58. This allows the height adjustment unit 22 to change the height h of the cutting blade 46. In this embodiment, the height h of the cutting blade 46 is represented by the distance between the lower end of the cutting blade 46 and the ground G. The height h of the cutting blade 46 is within a range of 10 mm to 80 mm, for example, and can be changed within a range of 20 mm to 60 mm in this embodiment.

[0046] As shown in FIG. 4, the detection unit 24 includes a wire detection sensor 64, a collision detection sensor 66, a lifting detection sensor 68, an angular velocity detection sensor 70, a motor current detection circuit 72, and a battery voltage detection circuit 74.

[0047] The wire detection sensor 64 is a sensor for detecting the wire 112 (see FIG. 1). The wire detection sensor 64 is, for example, a Hall sensor. In this embodiment, a predetermined electric signal is applied to the wire 112 from the charging station 110 (see FIG. 1). As a result, a magnetic signal corresponding to the predetermined electric signal is generated around the wire 112. The wire detection sensor 64 is configured to detect this magnetic signal and output it to the control unit 8. Based on the signal pattern and signal strength of the magnetic signal detected by the wire detection sensor 64, the control unit 8 can determine whether the robotic lawnmower 2 is approaching the wire 112, whether the robotic lawnmower 2 is located above the wire 112, etc.

[0048] The collision detection sensor 66 is a sensor for detecting when the robot lawnmower 2 collides with an obstacle. The collision detection sensor 66 is, for example, a Hall sensor. As shown in FIG. 5, the collision detection sensor 66 is provided on the base frame 26. A magnet 76 is provided on the body 28 at a location facing the collision detection sensor 66 in the up-down direction. The collision detection sensor 66 detects the strength of the magnetic field generated by the magnet 76 provided on the body 28. If the strength of the detected magnetic field is large, the collision detection sensor 66 outputs an H signal to the control unit 8 (see FIG. 4), and if the strength of the detected magnetic field is small, the collision detection sensor 66 outputs an L signal to the control unit 8. When the body 28 is in the position shown in FIG. 2, the position of the collision detection sensor 66 in the horizontal direction and the position of the magnet 76 in the horizontal direction overlap each other. Therefore, the strength of the magnetic field detected by the collision detection sensor 66 is large, and the collision detection sensor 66 outputs an H signal to the control unit 8. 2, the position of the collision detection sensor 66 in the horizontal direction and the position of the magnet 76 in the horizontal direction are offset from each other. As a result, the strength of the magnetic field detected by the collision detection sensor 66 decreases, and an L signal is output from the collision detection sensor 66 to the control unit 8.

[0049] The lifting detection sensor 68 is a sensor for detecting that the robotic lawnmower 2 has been lifted from the ground G. The lifting detection sensor 68 is, for example, an inductive sensor. As shown in FIG. 6, the lifting detection sensor 68 is provided on the base frame 26. A metal plate 78 is provided on the body 28 at a location facing the lifting detection sensor 68 in the up-down direction. The lifting detection sensor 68 detects whether the metal plate 78 provided on the body 28 is nearby. If the metal plate 78 is nearby, the lifting detection sensor 68 outputs an H signal to the control unit 8 (see FIG. 4), and if the metal plate 78 is not nearby, the lifting detection sensor 68 outputs an L signal to the control unit 8. When the body 28 is in the position shown in FIG. 2, the metal plate 78 is near the lifting detection sensor 68, so that the lifting detection sensor 68 outputs an H signal to the control unit 8. When the body 28 moves upward from the position shown in FIG. 2, the metal plate 78 moves away from the lifting detection sensor 68, so that the lifting detection sensor 68 outputs an L signal to the control unit 8.

[0050] 4 is provided on the base frame 26 (see FIG. 2). The angular velocity detection sensor 70 detects the angular velocity of the base frame 26, and outputs the detected angular velocity to the control unit 8.

[0051] The battery voltage detection circuit 74 detects the voltage value of the battery 30 (that is, the remaining charge of the battery 30), and outputs the detected voltage value to the control unit 8.

[0052] The motor current detection circuit 72 detects the value of the current supplied to each of the moving motors 44L, 44R and the working motor 48, and outputs the detected current values ​​to the control unit 8.

[0053] (Autonomous Driving) The following describes the autonomous driving executed by the control unit 8 (specifically, the processor 34). The autonomous driving in this embodiment differs in operation content depending on whether the automatic height adjustment function is on or off.

[0054] (Autonomous operation when automatic height adjustment function is on) When the automatic height adjustment function is on, the robotic lawnmower 2 changes the height h of the cutting blade 46 (see FIG. 2) in stages from the initial height to the target height. In this embodiment, the initial height is set to a value greater than the target height. For example, the initial height is set to 50 mm, and the target height is set to 30 mm. Therefore, the robotic lawnmower 2 lowers the height h of the cutting blade 46 in stages from the initial height to the target height. Below, referring to FIG. 7, the autonomous operation when the automatic height adjustment function is on will be described in detail.

[0055] The process shown in FIG. 7 is started when an instruction to start autonomous driving is given via the input operation unit 10 (see FIG. 4) or a user's communication terminal while the automatic height adjustment function is on.

[0056] In S2, the control unit 8 operates the height adjustment motor 54 (see FIG. 2) to adjust the height h of the cutting blade 46 to an initial height previously set by the user. After S2, the process proceeds to S4.

[0057] In S4, the control unit 8 determines whether or not the current time is within a work time zone. If the current time is not within a work time zone (NO), the process proceeds to S6.

[0058] In S6, the control unit 8 causes the robotic lawnmower 2 to wait at the charging station 110 (see FIG. 1). If the robotic lawnmower 2 is not at the charging station 110 when S6 begins, the control unit 8 causes the robotic lawnmower 2 to return to the charging station 110. Specifically, with the work motor 48 (see FIG. 4) stopped, the control unit 8 operates the movement motors 44L, 44R (see FIG. 4) so ​​that the robotic lawnmower 2 follows the wire 112 to the charging station 110. After that, with the work motor 48 and the movement motors 44L, 44R stopped, the control unit 8 causes the robotic lawnmower 2 to wait at the charging station 110. After S6, the process returns to S4.

[0059] If the current time is within the work time zone in S4 (YES), the process proceeds to S8. In S8, the control unit 8 starts mowing work with the robotic lawnmower 2. Specifically, the control unit 8 operates the movement motors 44L, 44R to move the robot body 4, while operating the work motor 48 to mow the grass with the cutting blade 46. This causes the height of the grass to be aligned to the height h of the cutting blade 46. After S8, the process proceeds to S10.

[0060] In S10, the control unit 8 judges whether a predetermined grass height uniformity condition is satisfied. The grass height uniformity condition is, for example, a condition under which the height of the grass in the working area WA (see FIG. 1) is estimated to be uniform across the board at the height h of the cutting blade 46. The grass height uniformity condition includes a first grass height uniformity condition in which the cumulative value of the mowing operation time in a state where the height h of the cutting blade 46 does not change exceeds a first operation time threshold. The "mowing operation time" here means the time elapsed from the start to the end of the mowing operation, excluding the time elapsed while the mowing operation is interrupted. The mowing operation time is, for example, the time during which the working motor 48 is operated while the mowing operation is being performed. The "cumulative value of the mowing operation time" is the sum of the mowing operation times for each mowing operation when the mowing operation is performed multiple times in a state where the height h of the cutting blade 46 does not change. The "first operation time threshold" is a time threshold determined based on the area of ​​the working area WA. A threshold table TT as shown in FIG. 8 is stored in the memory 36 of the control unit 8. The threshold table TT describes the first work time threshold to be determined in association with the area of ​​the work area WA. Therefore, the control unit 8 can determine the first work time threshold corresponding to the area of ​​the work area WA previously set by the user. In the threshold table TT, one first work time threshold is assigned to each of a plurality of area ranges. The grass height uniformity condition further includes a second grass height uniformity condition that the cumulative value of the grass mowing work time in a state where the battery 30 (see FIG. 4) is not charged exceeds a predetermined second work time threshold. The second work time threshold is, for example, 2.0 hours or more, and is 2.5 hours in this embodiment. Normally, when the height of the grass is aligned to the height h of the cutting blade 46, the load on the working motor 48 that drives the cutting blade 46 is reduced, so that the remaining charge of the battery 30 lasts longer. If the remaining charge of the battery 30 lasts longer, the cumulative value of the grass mowing work time in a state where the battery 30 is not charged also becomes longer accordingly. For this reason, if the cumulative time spent mowing without charging the battery 30 is long, it can be assumed that the height of the grass within the work area WA has become uniform across the board at the height h of the cutting blade 46. If any one of the above conditions is met, the control unit 8 determines that the uniform grass height condition is met (YES).If the uniform grass height condition is met (YES), the process proceeds to S12.

[0061] In S12, the control unit 8 turns on the uniform grass height flag, in other words, the control unit 8 stores in the memory 36 information indicating that the uniform grass height condition is met in S10.

[0062] If the grass height uniformity condition is not met in S10 (if NO), or after S12, the process proceeds to S14. In S14, the control unit 8 determines whether or not a predetermined feedback condition is met. The feedback condition includes a first feedback condition that the remaining charge of the battery 30 is low. Specifically, the first feedback condition is a condition that the voltage value of the battery 30 detected by the battery voltage detection circuit 74 (see FIG. 4) is equal to or lower than a predetermined voltage value (for example, 17.5 V). The feedback condition further includes a second feedback condition that the grass height uniformity flag is on. If any one of the above conditions is met, the control unit 8 determines that the feedback condition is met (YES). If the feedback condition is not met (if NO), the process returns to S10. If the feedback condition is met (if YES), the process proceeds to S16.

[0063] In S16, the control unit 8 ends the mowing operation started in S8 and returns the robotic lawnmower 2 to the charging station 110. Specifically, with the work motor 48 stopped, the control unit 8 operates the transport motors 44L, 44R so that the robotic lawnmower 2 follows the wire 112 to the charging station 110. After S16, the process proceeds to S18.

[0064] In S18, the control unit 8 docks the robotic lawnmower 2 to the charging station 110 and starts charging the battery 30. The control unit 8 then continues charging the battery 30 until a predetermined charging end condition is met. The charging end condition is, for example, that the voltage value of the battery 30 detected by the battery voltage detection circuit 74 is equal to or higher than a predetermined value (e.g., 20 V). When charging of the battery 30 ends in S18, the process proceeds to S20.

[0065] In S20, the control unit 8 determines whether the uniform grass height flag is on. If the uniform grass height flag is off (NO), the process returns to S4. If the uniform grass height flag is on (YES), the process proceeds to S22.

[0066] In S22, the control unit 8 determines whether the current height h of the blade 46 has reached the target height preset by the user. If the height h of the blade 46 has not reached the target height (i.e., the height h of the blade 46 is higher than the target height) (NO), the process proceeds to S24.

[0067] In S24, the control unit 8 operates the height adjustment motor 54 (see FIG. 2) to lower the height h of the cutting blade 46 by a predetermined amount (for example, 5 mm). Note that when S24 is executed, the robotic lawnmower 2 is at the charging station 110. This allows the height h of the cutting blade 46 to be lowered in a relatively safe location. In addition, the control unit 8 turns off the grass height uniformity flag in response to lowering the height h of the cutting blade 46. After S24, the process returns to S4.

[0068] If in S22 the height h of the cutting blade 46 has reached the target height (YES), the process proceeds to S26. In S26, the control unit 8 notifies the user that the height of the grass in the work area WA has been generally aligned to the target height. For example, the control unit 8 communicates with the user's communication terminal via the communication unit 12 (see FIG. 4) and causes the communication terminal to notify that the height of the grass in the work area WA has been generally aligned to the target height. After S26, the process shown in FIG. 7 ends.

[0069] The process shown in Fig. 7 also ends when an instruction to end autonomous driving is given via the input operation unit 10 or a user's communication terminal. The process shown in Fig. 7 also ends when the main power supply of the robotic lawnmower 2 is switched off via the input operation unit 10 or a user's communication terminal.

[0070] (Autonomous operation when automatic height adjustment function is turned off) When the automatic height adjustment function is turned off, the robotic lawnmower 2 continues to maintain the height h of the cutting blade 46 (see FIG. 2) at a fixed height preset by the user. Autonomous operation when the automatic height adjustment function is turned off will be described in detail below with reference to FIG.

[0071] The process shown in FIG. 9 is started when an instruction to start autonomous driving is given via the input operation unit 10 (see FIG. 4) or a user's communication terminal while the automatic height adjustment function is turned off.

[0072] In S32, the control unit 8 operates the height adjustment motor 54 (see FIG. 2) to adjust the height h of the cutting blade 46 to the fixed height. After S32, the process proceeds to S34.

[0073] In S34, the control unit 8 determines whether or not the current time is within the work time zone. If the current time is not within the work time zone (NO), the process proceeds to S36.

[0074] In S36, the control unit 8 causes the robotic lawnmower 2 to wait at the charging station 110 (see FIG. 1). If the robotic lawnmower 2 is not at the charging station 110 when S36 is started, the control unit 8 causes the robotic lawnmower 2 to return to the charging station 110. Specifically, with the working motor 48 (see FIG. 4) stopped, the control unit 8 operates the movement motors 44L, 44R (see FIG. 4) so ​​that the robotic lawnmower 2 follows the wire 112 to the charging station 110. After that, with the working motor 48 and the movement motors 44L, 44R stopped, the control unit 8 causes the robotic lawnmower 2 to wait at the charging station 110. After S36, the process returns to S34.

[0075] If the current time is within the work time zone in S34 (YES), the process proceeds to S38. In S38, the control unit 8 starts mowing work with the robotic lawnmower 2. Specifically, the control unit 8 operates the movement motors 44L, 44R to move the robot body 4, while operating the work motor 48 to mow the grass with the cutting blade 46. After S38, the process proceeds to S40.

[0076] In S40, the control unit 8 judges whether or not a predetermined feedback condition is satisfied. For example, this feedback condition is that the voltage value of the battery 30 detected by the battery voltage detection circuit 74 (see FIG. 4) is equal to or lower than a predetermined voltage value (for example, 17.5 V). If the feedback condition is not satisfied (NO), the process repeats S40. If the feedback condition is satisfied (YES), the process proceeds to S42.

[0077] In S42, the control unit 8 ends the mowing operation started in S38 and returns the robotic lawnmower 2 to the charging station 110. Specifically, with the work motor 48 stopped, the control unit 8 operates the transport motors 44L, 44R so that the robotic lawnmower 2 follows the wire 112 to the charging station 110. After S42, the process proceeds to S44.

[0078] In S44, the control unit 8 docks the robotic lawnmower 2 to the charging station 110 and starts charging the battery 30. The control unit 8 then continues charging the battery 30 until a predetermined charging end condition is met. This charging end condition is, for example, that the voltage value of the battery 30 detected by the battery voltage detection circuit 74 is equal to or higher than a predetermined value (e.g., 20 V). When charging of the battery 30 ends in S44, the process returns to S34.

[0079] The process shown in Fig. 9 ends when an instruction to end autonomous driving is given via the input operation unit 10 or a user's communication terminal. The process shown in Fig. 9 also ends when the main power supply of the robotic lawnmower 2 is switched off via the input operation unit 10 or a user's communication terminal.

[0080] (Operation of the robot lawnmower 2 when it encounters an obstacle) Regardless of whether the automatic height adjustment function is on or off, the control unit 8 repeatedly executes the process shown in FIG. 10 during the execution of autonomous driving.

[0081] In S52, the control unit 8 determines whether or not movement of the body 28 (see FIG. 2) relative to the base frame 26 (see FIG. 2) has been detected. Specifically, the control unit 8 determines whether or not an L signal has been output from at least one of the collision detection sensor 66 (see FIG. 4) and the lifting detection sensor 68 (see FIG. 4). If movement of the body 28 relative to the base frame 26 has not been detected (NO), the process proceeds to S54.

[0082] In S54, the control unit 8 determines that the movement of the robotic lawnmower 2 is not being impeded. After S54, the process returns to S52.

[0083] If movement of the body 28 relative to the base frame 26 is detected in S52 (YES), processing proceeds to S56. In S56, the control unit 8 determines that movement of the robotic lawnmower 2 has been impeded by an obstacle. The control unit 8 then stops the movement motors 44L, 44R (see FIG. 4) and the work motor 48 (see FIG. 4) to interrupt normal operation. Normal operation here refers to the mowing work and return operation performed by the robotic lawnmower 2 during autonomous driving. After S56, processing proceeds to S58.

[0084] In S58, the control unit 8 operates the movement motors 44L and 44R to cause the robotic lawnmower 2 to start an avoidance operation. The "avoidance operation" here refers to, for example, any of the following operations: a forward movement in which the robotic lawnmower 2 moves forward, a backward movement in which the robotic lawnmower 2 moves backward, a left turning movement in which the robotic lawnmower 2 turns left, and a right turning movement in which the robotic lawnmower 2 turns right. The "turning operation" here includes not only an operation in which the robotic lawnmower 2 turns on the spot, but also an operation in which the robotic lawnmower 2 turns while moving forward or backward. In this embodiment, the control unit 8 specifies the moving direction of the robotic lawnmower 2 before the normal operation was interrupted in S56. The control unit 8 then determines the avoidance operation to be started in S58 as an operation in which the robotic lawnmower 2 moves in the opposite direction to the moving direction before the normal operation was interrupted in S56. For example, if the robotic lawnmower 2 was moving forward before normal operation was interrupted in S56, the avoidance operation started in S58 will be moving backward. If the robotic lawnmower 2 was turning left before normal operation was interrupted in S56, the avoidance operation started in S58 will be turning right. After S58, processing proceeds to S60.

[0085] In S60, the control unit 8 judges whether or not movement of the body 28 relative to the base frame 26 is detected during the execution of the avoidance operation started immediately before (in S58 or S62). Specifically, the control unit 8 judges whether or not the signal output from at least one of the collision detection sensor 66 and the lifting detection sensor 68 is switched from an H signal to an L signal during the execution of the avoidance operation. Even if there is a sensor that continues to output an L signal from the start of the avoidance operation, the L signal output from the sensor is not switched from an H signal to an L signal during the execution of the avoidance operation. For this reason, in S60, the sensor does not judge YES. Please note that the YES / NO judgment in S60 differs from the YES / NO judgment in S52 in this respect. If movement of the body 28 relative to the base frame 26 is detected during the execution of the avoidance operation (if YES), the process proceeds to S62.

[0086] In S62, the control unit 8 causes the robotic lawnmower 2 to start an avoidance operation different from the previous avoidance operation. For example, if the previous avoidance operation was a forward movement, the control unit 8 causes the robotic lawnmower 2 to start a backward movement, a left turn movement, or a right turn movement. After S62, the process returns to S60.

[0087] If no movement of the body 28 relative to the base frame 26 is detected during the avoidance operation in S60 (if NO), the process proceeds to S64. In S64, the control unit 8 determines whether or not an overload on the movement motors 44L, 44R is detected during the avoidance operation that was started immediately before the determination of NO in S60. Specifically, the control unit 8 determines whether or not a situation in which the current value flowing through the movement motors 44L, 44R detected by the motor current detection circuit 72 (see FIG. 4) is equal to or greater than a predetermined current value (e.g., 3.0 A) continues for a predetermined time (e.g., 0.1 seconds) or more. If an overload on the movement motors 44L, 44R is detected during the avoidance operation (if YES), the process proceeds to S66.

[0088] In S66, the control unit 8 determines that the movement of the robotic lawnmower 2 (specifically, the avoidance operation) has been impeded by an obstacle. For example, if a portion of the robotic lawnmower 2 other than the body 28 (for example, the drive wheels 42L, 42R) is interfering with an obstacle, the movement of the robotic lawnmower 2 is impeded by the obstacle even though the movement of the body 28 is not detected (NO in S60). However, in this case, it is expected that the obstacle will act as a resistance and a larger load than usual will be applied to the movement motors 44L, 44R. Therefore, when the robotic lawnmower 2 of this embodiment detects an overload on the movement motors 44L, 44R (YES in S64), it determines that the movement of the robotic lawnmower 2 has been impeded by an obstacle. Also, in S66, the control unit 8 increments the number of times that it has determined that the movement of the robotic lawnmower 2 has been impeded by an obstacle by +1. This count number is reset to zero when the processing shown in Fig. 10 ends, and is therefore zero when the processing shown in Fig. 10 starts. After S66, the process proceeds to S68.

[0089] In S68, the control unit 8 determines whether the count number is equal to or greater than a predetermined number (e.g., 2 times). If the count number is less than the predetermined number (NO), the process proceeds to S62. If the count number is equal to or greater than the predetermined number (YES), the process proceeds to S70.

[0090] In S70, the control unit 8 determines that an abnormality has occurred in the robotic lawnmower 2, and stops the robotic lawnmower 2. Specifically, the control unit 8 stops the travel motors 44L, 44R and the work motor 48, and causes the robotic lawnmower 2 to wait in place. The control unit 8 also operates the display unit 14 (see FIG. 4) and the alarm unit 16 (see FIG. 4) to notify the user of the abnormality by sound or light. Alternatively, the control unit 8 communicates with a communication terminal (e.g., a smartphone) owned by the user via the communication unit 12 (see FIG. 4), and causes the communication terminal to notify the user of the abnormality. After S70, the process shown in FIG. 10 ends.

[0091] If no overload on the moving motors 44L and 44R is detected during the avoidance operation in S64 (if NO), the process proceeds to S72. In S72, the control unit 8 determines whether the avoidance operation started in S58 or S62 has ended. In this embodiment, the control unit 8 determines in advance how much to rotate each output shaft of the moving motors 44L and 44R when executing the avoidance operation. The control unit 8 monitors the amount of rotation of each output shaft of the moving motors 44L and 44R using a rotation detection sensor (resolver, etc.) provided on the moving motors 44L and 44R. For this reason, the control unit 8 determines that the avoidance operation has ended (YES) when, for example, the amount of rotation of each output shaft of the moving motors 44L and 44R after the robotic lawnmower 2 starts the avoidance operation reaches a predetermined amount of rotation. If the avoidance operation has not ended (if NO), the process returns to S60. If the avoidance operation has ended (if YES), the process proceeds to S74.

[0092] In S74, the control unit 8 determines that the movement of the robotic lawnmower 2 (specifically, the avoidance operation) is not being impeded. This is because no overload on the movement motors 44L, 44R is detected, and therefore it is presumed that the movement of the robotic lawnmower 2 has been completed without any problems. The control unit 8 then resumes the normal operation (lawnmowing or return operation) that was interrupted in S56. After S74, the processing shown in FIG. 10 ends.

[0093] (Example 2: Robotic lawnmower 202) The robotic lawnmower 202 has a configuration substantially similar to that of the robotic lawnmower 2 of the first embodiment (see Figs. 1 to 10). The robotic lawnmower 202 differs from the robotic lawnmower 2 of the first embodiment only in that the control unit 8 (see Fig. 4) executes the process shown in Fig. 11 instead of the process shown in Fig. 10. Therefore, only the process shown in Fig. 11 will be described below, and other descriptions will be omitted.

[0094] In S102, the control unit 8 determines whether or not movement of the body 28 (see FIG. 2) relative to the base frame 26 (see FIG. 2) has been detected. Specifically, the control unit 8 determines whether or not an L signal has been output from at least one of the collision detection sensor 66 (see FIG. 4) and the lifting detection sensor 68 (see FIG. 4). If movement of the body 28 relative to the base frame 26 has not been detected (NO), the process proceeds to S104.

[0095] In S104, the control unit 8 determines that there is no obstruction to the movement of the robotic lawnmower 202. After S104, the process returns to S102.

[0096] If movement of the body 28 relative to the base frame 26 is detected in S102 (YES), the process proceeds to S106. In S106, the control unit 8 determines that the movement of the robotic lawnmower 202 has been impeded by an obstacle. The control unit 8 then stops the movement motors 44L, 44R (see FIG. 4) and the work motor 48 (see FIG. 4) and interrupts normal operation (lawnmowing or returning). After S106, the process proceeds to S108.

[0097] In S108, the control unit 8 operates the travel motors 44L, 44R to cause the robotic lawnmower 202 to perform a straight movement operation (i.e., forward movement or backward movement). In this embodiment, the control unit 8 determines whether the traveling direction of the robotic lawnmower 202 was forward or backward before the normal operation was interrupted in S106. The control unit 8 then determines the straight movement operation to be performed in S108 as an operation in which the robotic lawnmower 202 moves in the opposite direction to the traveling direction before the normal operation was interrupted in S106. For example, if the robotic lawnmower 202 was performing a forward movement operation before the normal operation was interrupted in S106, the straight movement operation to be performed in S108 is a backward movement operation. When the straight movement operation ends, the process proceeds to S110.

[0098] In S110, the control unit 8 operates the travel motors 44L, 44R to cause the robotic lawnmower 202 to start a turning operation (i.e., a left turning operation or a right turning operation). At this time, the control unit 8 randomly determines the turning direction and target turning angle of the robotic lawnmower 202. The target turning angle is determined to be an angle within a range of, for example, 10 degrees to 180 degrees. The control unit 8 controls the travel motors 44L, 44R so as to turn the robotic lawnmower 202 by the determined target turning angle in the determined turning direction. After S110, the process proceeds to S112.

[0099] In S112, the control unit 8 determines whether the turning angle of the robotic lawnmower 202 since it started its turning operation has reached the target turning angle. The control unit 8 is configured to measure the turning angle of the robotic lawnmower 202 since it started its turning operation using an angular velocity detection sensor 70 (see FIG. 4) provided on the base frame 26. If the turning angle of the robotic lawnmower 202 since it started its turning operation has not reached the target turning angle (NO), the process proceeds to S114.

[0100] In S114, the control unit 8 determines whether the time that has elapsed since the robotic lawnmower 202 started turning in S110 is equal to or greater than a predetermined time (e.g., 6.0 seconds). If the time that has elapsed is less than the predetermined time (NO), the process returns to S112. If the time that has elapsed is equal to or greater than the predetermined time (YES), the process proceeds to S116.

[0101] In S116, the control unit 8 determines that the movement (specifically, the turning operation) of the robotic lawnmower 202 is impeded by an obstacle. For example, if a portion of the robotic lawnmower 202 other than the body 28 (for example, the drive wheels 42L, 42R) is interfering with an obstacle, the movement of the robotic lawnmower 202 is impeded by the obstacle even though the movement of the body 28 is not detected (NO in S60). In this case, it is expected that the obstacle will act as a resistance and the turning angle of the robotic lawnmower 202 will not change at all even though the moving motors 44L, 44R are operating. Therefore, in this embodiment, the robotic lawnmower 202 determines that the movement of the robotic lawnmower 202 is impeded by an obstacle if the situation in which the turning angle of the robotic lawnmower 202 does not reach the target turning angle continues (YES in S114). Also, in S116, the control unit 8 increments the number of times it has determined that the movement of the robotic lawnmower 202 has been impeded by an obstacle by +1. This count is reset to zero when the processing shown in Fig. 11 ends, so it is zero when the processing shown in Fig. 11 starts. After S116, the processing proceeds to S118.

[0102] In S118, the control unit 8 determines whether the count number is equal to or greater than a predetermined number (for example, 2 times). If the count number is less than the predetermined number (NO), the process proceeds to S120.

[0103] In S120, the control unit 8 causes the robotic lawnmower 202 to start a turning operation in the opposite direction to the previous turning operation. For example, if the previous turning operation was a left turning operation, the control unit 8 causes the robotic lawnmower 202 to start a right turning operation. After S120, the process returns to S112.

[0104] If the count number is equal to or greater than the predetermined number in S118 (YES), the process proceeds to S122. In S122, the control unit 8 determines that an abnormality has occurred in the robotic lawnmower 202 and stops the robotic lawnmower 202. Specifically, the control unit 8 stops the travel motors 44L, 44R and the work motor 48, and causes the robotic lawnmower 202 to wait in place. The control unit 8 also operates the display unit 14 (see FIG. 4) and the alarm unit 16 (see FIG. 4) to notify the user of the occurrence of an abnormality by sound or light. Alternatively, the control unit 8 communicates with a communication terminal (e.g., a smartphone) owned by the user via the communication unit 12 (see FIG. 4) and causes the communication terminal to notify the user of the occurrence of an abnormality. After S122, the process shown in FIG. 11 ends.

[0105] In S112, if the turning angle of the robotic lawnmower 202 since the robotic lawnmower 202 started its turning operation has reached the target turning angle (YES), the process proceeds to S124.

[0106] In S124, the control unit 8 determines that the movement (specifically, the turning operation) of the robotic lawnmower 202 is not hindered by an obstacle. This is because the turning angle of the robotic lawnmower 202 has reached the target turning angle, and therefore it is presumed that the movement of the robotic lawnmower 202 has ended smoothly. The control unit 8 also resumes the normal operation (lawnmowing work or return operation) that was interrupted in S106. After S124, the processing shown in FIG. 11 ends.

[0107] (Example 3: Robotic lawnmower 302) The robotic lawnmower 302 has a configuration similar to that of the robotic lawnmower 2 of the first embodiment (see Figs. 1-10). The robotic lawnmower 302 differs from the robotic lawnmower 2 of the first embodiment only in that the control unit 8 (see Fig. 4) executes the process shown in Fig. 12 instead of the process shown in Fig. 10. The process shown in Fig. 12 reuses the process shown in Fig. 10, with S60 and S64 replaced by S160 and S164. Therefore, in the following, only S160 and S164 of the process shown in Fig. 12 will be described, and the rest of the description will be omitted.

[0108] S160 is executed after S58 or after S62. In S160, the control unit 8 judges whether or not movement of the body 28 relative to the base frame 26 is detected during the execution of the avoidance operation started immediately before (S58 or S62). Specifically, the control unit 8 judges whether or not a signal output from at least one of the collision detection sensor 66 (see FIG. 4) and the lifting detection sensor 68 (see FIG. 4) is switched from an H signal to an L signal during the execution of the avoidance operation. Note that even if there is a sensor that continues to output an L signal from the start of the avoidance operation, the L signal output from the sensor is not switched from an H signal to an L signal during the execution of the avoidance operation. For this reason, in S160, the sensor will not judge YES. Please note that the YES / NO judgment in S160 is different from the YES / NO judgment in S52 in this respect. If movement of the body 28 relative to the base frame 26 is not detected during the execution of the avoidance operation (in the case of NO), the process proceeds to S72. If movement of the body 28 relative to the base frame 26 is detected during the execution of the avoidance operation (YES), the process proceeds to S164.

[0109] In S164, the control unit 8 judges whether or not an overload on the movement motors 44L, 44R is detected during the execution of the avoidance operation started immediately before the judgment in S160 is NO. Specifically, the control unit 8 judges whether or not a situation in which the current value flowing through the movement motors 44L, 44R detected by the motor current detection circuit 72 (see FIG. 4) is equal to or greater than a predetermined current value (e.g., 3.0 A) continues for a predetermined time (e.g., 0.1 seconds) or more. If an overload on the movement motors 44L, 44R is not detected during the execution of the avoidance operation (if NO), the process proceeds to S62. If an overload on the movement motors 44L, 44R is detected during the execution of the avoidance operation (if YES), the process proceeds to S66.

[0110] Even if the movement of the body 28 is detected (YES in S160), if an overload on the travel motors 44L, 44R is not detected (NO in S164), it is possible, but not certain, that the movement of the robotic lawnmower 302 is hindered by an obstacle. In this case, the robotic lawnmower 302 of this embodiment postpones the determination of whether the movement of the robotic lawnmower 302 is hindered by an obstacle and performs a different avoidance operation. Then, if the movement of the body 28 is detected (YES in S160) and an overload on the travel motors 44L, 44R is detected (YES in S164), it determines that the movement of the robotic lawnmower 302 is hindered by an obstacle. This makes it possible to prevent the control unit 8 from making an erroneous determination (determining that the movement of the robotic lawnmower 302 is hindered by an obstacle when in fact the movement of the robotic lawnmower 302 is not hindered by an obstacle).

[0111] (Example 4: Robotic lawnmower 402) The robotic lawnmower 402 has a configuration substantially similar to that of the robotic lawnmower 2 of the first embodiment (see Figs. 1-10). The robotic lawnmower 402 differs from the robotic lawnmower 2 of the first embodiment only in that the control unit 8 (see Fig. 4) executes the process shown in Fig. 13 instead of the process shown in Fig. 7. Therefore, only the process shown in Fig. 13 will be described below, and other descriptions will be omitted.

[0112] In S202, the control unit 8 operates the height adjustment motor 54 (see FIG. 2) to adjust the height h of the cutting blade 46 (see FIG. 2) to the initial height previously set by the user. After S202, the process proceeds to S204.

[0113] In S204, the control unit 8 determines whether or not the current time is within the work time zone. If the current time is not within the work time zone (NO), the process proceeds to S206.

[0114] In S206, the control unit 8 causes the robotic lawnmower 402 to wait at the charging station 110 (see FIG. 1). If the robotic lawnmower 402 is not at the charging station 110 when S206 is started, the control unit 8 causes the robotic lawnmower 402 to return to the charging station 110. Specifically, with the working motor 48 (see FIG. 4) stopped, the control unit 8 operates the movement motors 44L, 44R (see FIG. 4) so ​​that the robotic lawnmower 402 follows the wire 112 to the charging station 110. After that, with the working motor 48 and the movement motors 44L, 44R stopped, the control unit 8 causes the robotic lawnmower 402 to wait at the charging station 110. After S206, the process returns to S204.

[0115] If the current time is within the work time zone in S204 (YES), the process proceeds to S208. In S208, the control unit 8 starts mowing work with the robotic lawnmower 402. Specifically, the control unit 8 operates the movement motors 44L, 44R to move the robot body 4, while operating the work motor 48 to cut the grass with the cutting blade 46 (see FIG. 2). This causes the height of the grass to be aligned to the height h of the cutting blade 46. After S208, the process proceeds to S210.

[0116] In S210, the control unit 8 determines whether a predetermined grass height uniformity condition is met. The grass height uniformity condition here is substantially the same as that described in the first embodiment, and therefore will not be described here. If the grass height uniformity condition is met (YES), the process proceeds to S212.

[0117] In S212, the control unit 8 determines whether the current height h of the blade 46 has reached the target height preset by the user. If the height h of the blade 46 has not reached the target height (i.e., the height h of the blade 46 is higher than the target height) (NO), the process proceeds to S214.

[0118] In S214, the control unit 8 operates the height adjustment motor 54 to lower the height h of the cutting blade 46 by a predetermined amount (for example, 5 mm).

[0119] If the height h of the cutting blade 46 has reached the target height in S212 (YES), the process proceeds to S216. In S216, the control unit 8 turns on a target height reached flag, which indicates that the height of the grass in the work area WA has been set to the target height overall.

[0120] If the uniform grass height condition is not met in S210 (if NO), after S214 or after S216, processing proceeds to S218. In S218, the control unit 8 determines whether or not a predetermined return condition is met. The return condition here is substantially the same as that described in the first embodiment, and therefore description thereof will be omitted. If the return condition is not met (if NO), processing returns to S210. If the return condition is met (if YES), processing proceeds to S220.

[0121] In S220, the control unit 8 ends the mowing operation started in S208 and returns the robotic lawnmower 402 to the charging station 110. Specifically, with the work motor 48 stopped, the control unit 8 operates the travel motors 44L, 44R so that the robotic lawnmower 402 follows the wire 112 to the charging station 110. After S220, the process proceeds to S222.

[0122] In S222, the control unit 8 docks the robotic lawnmower 402 to the charging station 110 and starts charging the battery 30 (see FIG. 4). The control unit 8 then continues charging the battery 30 until a predetermined charging end condition is met. The charging end condition is, for example, that the voltage value of the battery 30 detected by the battery voltage detection circuit 74 (see FIG. 4) is equal to or higher than a predetermined value (e.g., 20 V). When charging of the battery 30 ends in S222, the process proceeds to S224.

[0123] In S224, the control unit 8 determines whether the target height reach flag is on. If the target height reach flag is off (if NO), the process returns to S204. If the target height reach flag is on (if YES), the process proceeds to S226.

[0124] In S226, the control unit 8 notifies the user that the height of the grass in the work area WA has been generally aligned to the target height. The control unit 8 communicates with the user's communication terminal via the communication unit 12 (see FIG. 4), for example, and causes the communication terminal to notify the user that the height of the grass in the work area WA has been generally aligned to the target height. After S226, the process shown in FIG. 13 ends.

[0125] (Modification) The working robot may be a robot other than the robotic lawnmower 2, 202, 302, 402. For example, the working robot may be a robot vacuum cleaner equipped with a brush and / or a suction mechanism for collecting debris such as dust. In this case, the work motor 48 may be used as a motor for driving the brush and / or the suction mechanism. The working robot may also be a rebar binding robot equipped with a rebar binding mechanism for binding the intersections of multiple rebars. In this case, the work motor 48 may be used as a motor for driving the rebar binding mechanism.

[0126] A power cord connected to an external power source (e.g., a commercial power source) may be attached to the robotic lawnmower 2, 202, 302, 402. In this case, the robotic lawnmower 2, 202, 302, 402 may be configured to operate using power supplied from the external power source via the power cord.

[0127] The robotic lawnmower 2, 202, 302, 402 may not be equipped with the battery 30. Instead, a rechargeable battery pack such as a lithium-ion battery may be detachably attached to the robot body 4. In this case, the robotic lawnmower 2, 202, 302, 402 may be configured to operate using power supplied from the battery pack.

[0128] The moving unit 18 may be equipped with other moving mechanisms (e.g., crawlers, side steppers) instead of the casters 40L, 40R and the drive wheels 42L, 42R. The side stepper here is a mechanism for moving the robot body 4 in the left-right direction. When the moving unit 18 is equipped with a side stepper, the avoidance operation may be an operation for moving the robot body 4 in the left or right direction by the side stepper.

[0129] The feedback condition used in S14 of Fig. 7 does not have to include the second feedback condition. Instead, the feedback condition used in S14 of Fig. 7 may include a third feedback condition in which the uniform grass height flag is on and the remaining charge of the battery 30 is relatively high (for example, the voltage value of the battery 30 is 19 V or higher).

[0130] The amount of descent of the height h of the cutting blade 46 in S24 of FIG. 7 (or S214 of FIG. 13) does not have to be a predetermined amount. For example, the control unit 8 may randomly determine the amount of descent of the height h of the cutting blade 46. Alternatively, the control unit 8 may reduce the amount of descent of the height h of the cutting blade 46 the next time S24 (or S214) is executed compared to the amount of descent of the height h of the cutting blade 46 the first time S24 (or S214) is executed during autonomous driving. Alternatively, the amount of descent of the height h of the cutting blade 46 may be changeable by the user via the input operation unit 10 or a communication terminal.

[0131] The robotic lawnmower 2, 202, 302, 402 may have a mapping function for constructing map information of the working area WA. For example, the control unit 8 may construct the map information by acquiring the movement history of the robotic lawnmower 2, 202, 302, 402 using a GPS. The map information of the working area WA may include the area of ​​the working area WA. This allows the control unit 8 to acquire the area of ​​the working area WA even if the user does not set the area of ​​the working area WA.

[0132] 10, after S58 or after S62, the process may skip S60 and proceed to S64. In other words, while the robotic lawnmower 2 is performing an avoidance operation, the control unit 8 may determine whether or not the movement of the robotic lawnmower 2 is being impeded by an obstacle based only on the detection result of the motor current detection circuit 72, without based on the detection results of the collision detection sensor 66 and the lifting detection sensor 68.

[0133] 10, if movement of the body 28 relative to the base frame 26 is detected while an avoidance operation is being performed (YES), the process may proceed to S66. That is, the control unit 8 may determine that the movement of the robotic lawnmower 2 has been impeded by an obstacle even if movement of the body 28 is detected while an avoidance operation is being performed.

[0134] 10 (or S160 in FIG. 12), the control unit 8 may determine whether or not an L signal is being output from at least one of the collision detection sensor 66 and the lifting detection sensor 68, instead of determining whether or not the signal output from at least one of the collision detection sensor 66 and the lifting detection sensor 68 has switched from an H signal to an L signal during execution of the avoidance operation. That is, the control unit 8 may determine YES if the L signal is simply being output, even if there is no switch from an H signal to an L signal.

[0135] 10 (or S164 in FIG. 12), the control unit 8 may determine whether the current value flowing through the travel motors 44L, 44R detected by the motor current detection circuit 72 has reached or exceeded a predetermined current value, instead of determining whether the state in which the current value flowing through the travel motors 44L, 44R detected by the motor current detection circuit 72 has remained at or above a predetermined current value for or longer than a predetermined time. That is, the control unit 8 may determine YES at the timing when the current value flowing through the travel motors 44L, 44R detected by the motor current detection circuit 72 has reached or exceeded a predetermined current value.

[0136] The robotic lawnmower 2, 202, 302, 402 may further include an inclination angle detection sensor (e.g., a gyro sensor) that detects the inclination angle of the base frame 26 with respect to the horizontal direction. In this case, in S52 and S60 of Fig. 10 (or S102 of Fig. 11, and S52 and S160 of Fig. 12), the control unit 8 may determine whether the inclination angle of the base frame 26 detected by the inclination angle detection sensor exceeds a predetermined angle threshold (e.g., 90 degrees). Alternatively, the control unit 8 may determine whether an L signal is output from at least one of the collision detection sensor 66 (see Fig. 4) and the lifting detection sensor 68 (see Fig. 4) and whether the inclination angle of the base frame 26 detected by the inclination angle detection sensor exceeds a predetermined angle threshold. 10 (or S164 in FIG. 12), the control unit 8 may determine whether the tilt angle of the base frame 26 detected by the tilt angle detection sensor exceeds a predetermined angle threshold (e.g., 90 degrees). Alternatively, the control unit 8 may determine whether an overload on the travel motors 44L, 44R is detected and the tilt angle of the base frame 26 detected by the tilt angle detection sensor exceeds a predetermined angle threshold. In this way, the control unit 8 may determine that the movement of the robotic lawnmower 2, 202, 302, 402 is hindered by an obstacle even when the tilt angle of the base frame 26 is an excessively large value.

[0137] (Features of the embodiment) As described above, in one or more embodiments, the robotic lawnmower 2, 202, 302, 402 (examples of a working robot) comprises a robot body 4, a moving unit 18 that moves the robot body 4, a cutting blade 46 (working unit 20) supported by the robot body 4, a height adjustment unit 22 that changes the height h of the cutting blade 46 relative to the robot body 4, and a control unit 8. The control unit 8 is configured to be capable of performing autonomous operation including a work process (S8, S14, S16 in FIG. 7) (or S38, S40, S42 in FIG. 9) (or S208, S218, S220 in FIG. 13) in which the robot body 4 is moved by the moving unit 18 while the cutting blade 46 is used to perform grass cutting work, and a height adjustment process (S2, S10, S12, S20, S22, S24, S26 in FIG. 7) (or S202, S210, S212, S214, S216, S224, S226 in FIG. 13) in which the height adjustment unit 22 adjusts the height h of the cutting blade 46 relative to the robot body 4 in multiple stages. The robotic lawnmower 2, 202, 302, 402 can be switched between a state in which the automatic height adjustment function is on (an example of a first state in which the control unit performs height adjustment processing during autonomous driving) and a state in which the automatic height adjustment function is off (an example of a second state in which the control unit does not perform height adjustment processing during autonomous driving).

[0138] According to the above configuration, the robotic lawnmower 2, 202, 302, 402 can adjust the height h of the cutting blade 46 without the need for manual operation by the user by performing the height adjustment process while performing autonomous driving. This eliminates the need for the user to monitor the progress of the work performed by the robotic lawnmower 2, 202, 302, 402, improving the usability of the robotic lawnmower 2, 202, 302, 402. However, in some cases, it may be desirable not to perform the height adjustment process. For example, this is the case when the user wishes to keep the height h of the cutting blade 46 constant throughout the autonomous driving. Furthermore, according to the above configuration, the state of the robotic lawnmower 2, 202, 302, 402 can be switched between a state in which the automatic height adjustment function is on and a state in which the automatic height adjustment function is off. This allows the user to select whether or not to perform the height adjustment process while performing autonomous driving, further improving the usability of the robotic lawnmower 2, 202, 302, 402.

[0139] In one or more embodiments, the robotic lawnmower 2, 202, 302, 402 further includes an input operation unit 10 and a communication unit 12 (examples of an input unit) that accept input from a user. The control unit 8 executes a height adjustment process based on the initial height and target height (examples of input values) input to the input operation unit 10 and the communication unit 12.

[0140] According to the above configuration, the height adjustment process is executed based on the initial height and target height input by the user to the input operation unit 10 and the communication unit 12. This allows the height adjustment process to be tailored to the environment in which the user will be using the robotic lawnmower 2, 202, 302, 402 and the type of work that the user wants the robotic lawnmower 2, 202, 302, 402 to perform, further improving the ease of use of the robotic lawnmower 2, 202, 302, 402.

[0141] In one or more embodiments, the robotic lawnmower 2, 202, 302, 402 includes a robot body 4, a moving unit 18 that moves the robot body 4, a cutting blade 46 (working unit 20) supported by the robot body 4, a height adjustment unit 22 that changes the height h of the cutting blade 46 relative to the robot body 4, an input operation unit 10 and a communication unit 12 (examples of input units) that accept input from a user, and a control unit 8. The control unit 8 is configured to be capable of performing autonomous driving including a task process (S8, S14, S16 in FIG. 7) (or S38, S40, S42 in FIG. 9) (or S208, S218, S220 in FIG. 13) of performing grass cutting task with the blade 46 while moving the robot body 4 by the moving unit 18, and a height adjustment process (S2, S10, S12, S20, S22, S24, S26 in FIG. 7) (or S202, S210, S212, S214, S216, S224, S226 in FIG. 13) of adjusting the height h of the blade 46 relative to the robot body 4 in multiple stages by the height adjustment unit 22. The control unit 8 performs the height adjustment process based on the initial height and the target height (examples of input values) input to the input operation unit 10 and the communication unit 12.

[0142] According to the above configuration, the robotic lawnmower 2, 202, 302, 402 can adjust the height h of the cutting blade 46 without the need for manual operation by the user by performing the height adjustment process while performing autonomous driving. This eliminates the need for the user to monitor the progress of the work performed by the robotic lawnmower 2, 202, 302, 402, improving the usability of the robotic lawnmower 2, 202, 302, 402. Furthermore, according to the above configuration, the height adjustment process is performed based on the initial height and target height input by the user to the input operation unit 10 and the communication unit 12. This allows the height adjustment process to be tailored to the environment in which the robotic lawnmower 2, 202, 302, 402 is used and the work content that the user wants the robotic lawnmower 2, 202, 302, 402 to perform, further improving the usability of the robotic lawnmower 2, 202, 302, 402.

[0143] In one or more embodiments, the height adjustment process includes a first height adjustment process (S2 in FIG. 7) (or S202 in FIG. 13) in which the height h of the cutting blade 46 relative to the robot body 4 is set as an initial height, and a second height adjustment process (S10, S12, S20, S22, S24 in FIG. 7) (or S210, S212, S214, S216, S224 in FIG. 13) in which the height h of the cutting blade 46 relative to the robot body 4 is changed from the initial height to a target height. The input value includes both the initial height and the target height.

[0144] Depending on the work content, there may be cases where it is desired to determine in advance the height h of the cutting blade 46 immediately after autonomous operation starts, and the height h of the cutting blade 46 some time after autonomous operation starts. With the above configuration, it is possible to determine in advance the height h of the cutting blade 46 immediately after autonomous operation starts (initial height), and the height h of the cutting blade 46 some time after autonomous operation starts (target height). This can further improve the usability of the robotic lawnmower 2, 202, 302, 402.

[0145] In one or more embodiments, the control unit 8 executes S24 in Fig. 7 (or S214 in Fig. 13) multiple times (an example of executing the second height adjustment process in multiple stages) so as to change the height h of the cutting blade 46 relative to the robot body 4 from the initial height to the target height in multiple stages. After S24 in Fig. 7 (or after S214 in Fig. 13) (an example of after each stage of the second height adjustment process is completed), the control unit 8 executes the work process until a grass height uniformity condition (an example of a predetermined condition) is satisfied, and then starts S24 in Fig. 7 (or S214 in Fig. 13) (an example of the next stage of the second height adjustment process).

[0146] Depending on the type of work, it may be desirable to change the height h of the cutting blade 46 in multiple stages and perform lawn mowing work with the cutting blade 46 each time the height h of the cutting blade 46 changes. With the above configuration, it is possible to change the height h of the cutting blade 46 in multiple stages from the initial height to the target height, and perform lawn mowing work with the cutting blade 46 each time the height h of the cutting blade 46 changes. This can further improve the ease of use of the robotic lawnmower 2, 202, 302, 402.

[0147] In one or more embodiments, the control unit 8 changes the height h of the cutting blade 46 relative to the robot body 4 by a predetermined amount (5 mm) in S24 of FIG. 7 (or S214 of FIG. 13) (examples of each stage of the second height adjustment process).

[0148] According to the above configuration, the change range of the height h of the cutting blade 46 is constant at each stage of the second height adjustment process. This makes it possible to keep the load on the cutting blade 46 constant during the grass cutting work that is performed each time the height h of the cutting blade 46 changes.

[0149] In one or more embodiments, the control unit 8 is configured to acquire the area of ​​the work area WA (an example of a work area). The grass height uniformity condition includes a first grass height uniformity condition (an example of a condition based on the work area).

[0150] According to the above configuration, the grass height uniformity condition (i.e., the end condition of the work process carried out between each stage of the second height adjustment process) is based on the area of ​​the work area WA. Therefore, for example, if the area of ​​the work area WA is small, the work process can be ended in a short time, and if the area of ​​the work area WA is large, the work process can be carried out for a long time. This allows the lawn mowing work by the cutting blade 46 to be performed just enough for the area of ​​the work area WA every time the height h of the cutting blade 46 changes.

[0151] In one or more embodiments, the uniform grass height condition includes the time during which the cutting blade 46 performs mowing work after each stage of the second height adjustment process exceeds a first work time threshold (an example of a work time threshold) determined based on the area of ​​the work area WA.

[0152] With the above configuration, when the working area WA is small, the work process can be completed in a short time, and when the working area WA is large, the work process can be performed for a long time. This allows the lawn mowing work by the cutting blade 46 to be performed just enough for the area of ​​the working area WA every time the height h of the cutting blade 46 changes.

[0153] In one or more embodiments, the control unit 8 stores a threshold table TT in which one time threshold is assigned to each of a plurality of area ranges. When the area of ​​the work area WA is acquired, the control unit 8 refers to the threshold table TT and determines the time threshold assigned to the area range to which the area of ​​the work area WA belongs as the first work time threshold.

[0154] According to the above configuration, the process by which the control unit 8 determines the time threshold value can be simplified.

[0155] In one or more embodiments, the working unit 20 includes a cutting blade 46 for cutting grass. The target height is lower than the initial height. In the second height adjustment process, the control unit 8 lowers the height h of the cutting blade 46 relative to the robot body 4 from the initial height to the target height.

[0156] According to the above configuration, the working robot functions as the robotic lawnmower 2, 202, 302, 402. The grass scraps cut by the robotic lawnmower 2, 202, 302, 402 may be spread on the lawn and used as mulch (so-called grass mulch). In this case, the smaller the size of the grass scraps, the faster the grass scraps will decay, so this is effective in promoting the growth of the lawn. According to the above configuration, the robotic lawnmower 2, 202, 302, 402 cuts the lawn in multiple stages, so the size of the cut grass scraps is relatively small. This makes it possible to effectively promote the growth of the lawn when the grass scraps are used as grass mulch.

[0157] In one or more embodiments, the input unit includes an input operation unit 10 (an example of a main body input unit) provided on the robot main body 4.

[0158] The robotic lawnmower 2, 202, 302, 402 may be configured to only accept input from the user via a communication terminal. However, in this configuration, when a user input is required and the robotic lawnmower 2, 202, 302, 402 is near the user but the communication terminal is not near the user, the user may feel annoyed. According to the above configuration, the robot body 4 of the robotic lawnmower 2, 202, 302, 402 is provided with an input operation unit 10 that accepts input from the user. Therefore, if the robotic lawnmower 2, 202, 302, 402 is near the user, the user can input to the robotic lawnmower 2, 202, 302, 402 even if the communication terminal is not near the user. This reduces the annoyance felt by the user.

[0159] In one or more embodiments, the robotic lawnmower 2, 202, 302, 402 further includes a battery 30 that is rechargeable and supplies power to the robotic lawnmower 2, 202, 302, 402. The autonomous driving further includes a charging process (S16, S18 in FIG. 7) (or S42, S44 in FIG. 9) (or S220, S222 in FIG. 13) in which the robotic lawnmower 2, 202, 302, 402 is returned to the charging station 110 to charge the battery 30. In the height adjustment process, the control unit 8 changes the height h of the cutting blade 46 relative to the robot body 4 when the robotic lawnmower 2, 202, 302, 402 is at the charging station 110. The control unit 8 does not change the height h of the cutting blade 46 relative to the robot body 4 when the robotic lawnmower 2, 202, 302, 402 is not at the charging station 110.

[0160] There may be obstacles in places other than the charging station 110. For this reason, if the height h of the cutting blade 46 is changed when the robotic lawnmower 2, 202, 302, 402 is not at the charging station 110, there is a risk that the obstacles will interfere with the cutting blade 46. With the above configuration, the height h of the cutting blade 46 is not changed when the robotic lawnmower 2, 202, 302, 402 is not at the charging station 110, and the height h of the cutting blade 46 is changed only when the robotic lawnmower 2, 202, 302, 402 is at the charging station 110. This makes it possible to prevent obstacles from interfering with the cutting blade 46. [Explanation of symbols]

[0161] 2: robot lawnmower, 4: robot body, 6: power supply unit, 8: control unit, 10: input operation unit, 12: communication unit, 14: display unit, 16: alarm unit, 18: moving unit, 20: working unit, 22: height adjustment unit, 24: detection unit, 26: base frame, 28: body, 30: battery, 32: charging interface, 34: processor, 36: memory, 38: power supply circuit, 40L: caster, 40R: caster, 42L: drive wheel, 42R: drive wheel, 44L: moving motor, 44R: moving motor, 46: cutting blade, 48: working motor, 50: output shaft, 52: height adjustment Mechanism, 54: Height adjustment motor, 56: Female thread, 58: Outer cylinder, 60: Male thread, 62: Inner cylinder, 64: Wire detection sensor, 66: Collision detection sensor, 68: Lifting detection sensor, 70: Angular velocity detection sensor, 72: Motor current detection circuit, 74: Battery voltage detection circuit, 76: Magnet, 78: Metal plate, 100: Site, 102: House, 104: Pond, 106: Road, 110: Charging station, 112: Wire, 202: Robotic lawnmower, 302: Robotic lawnmower, 402: Robotic lawnmower, G: Ground, TT: Threshold table, WA: Working area

Claims

1. A work robot, The robot body, A moving unit that moves the robot body; A working unit supported by the robot body; a height adjustment unit that changes the height of the working unit relative to the robot body; A control unit, The control unit is a work process in which the working unit performs a work while the moving unit moves the robot body; a height adjustment process for adjusting the height of the working unit relative to the robot body in a plurality of stages by the height adjustment unit, The working robot is switchable between a first state in which the control unit executes the height adjustment process during the autonomous driving, and a second state in which the control unit does not execute the height adjustment process during the autonomous driving.

2. Further comprising an input unit for accepting input from a user, The working robot according to claim 1 , wherein the control unit executes the height adjustment process based on an input value inputted to the input unit.

3. A work robot, The robot body, A moving unit that moves the robot body; A working unit supported by the robot body; a height adjustment unit that changes the height of the working unit relative to the robot body; an input section for accepting input from a user; A control unit, The control unit is a work process in which the working unit performs a work while the moving unit moves the robot body; a height adjustment process for adjusting the height of the working unit relative to the robot body in a plurality of stages by the height adjustment unit, The control unit executes the height adjustment process based on an input value input to the input unit.

4. The height adjustment process includes: a first height adjustment process for adjusting the height of the working unit relative to the robot body to an initial height; a second height adjustment process for changing a height of the working unit relative to the robot body from the initial height to a target height, The working robot according to claim 2 or 3, wherein the input value includes at least one of the initial height and the target height.

5. the control unit executes the second height adjustment process in a plurality of stages so as to change a height of the working unit relative to the robot body from the initial height to the target height in a plurality of stages; The working robot according to claim 4 , wherein the control unit executes the work process until a predetermined condition is satisfied after each stage of the second height adjustment process is completed, and then starts a next stage of the second height adjustment process.

6. The working robot according to claim 5 , wherein the control unit changes the height of the working unit relative to the robot body by a predetermined amount in each stage of the second height adjustment process.

7. The control unit is configured to be able to acquire a work area, The working robot according to claim 5 or 6, wherein the predetermined condition includes a condition based on an area of ​​the work area.

8. 8. The working robot of claim 7, wherein the predetermined condition includes a condition in which a time during which the working unit performs work after each stage of the second height adjustment process is completed exceeds a work time threshold determined based on an area of ​​the work area.

9. the control unit stores a threshold table in which one time threshold is assigned to each of a plurality of area ranges; The working robot of claim 8 , wherein when the work area is acquired, the control unit refers to the threshold table and determines, as the work time threshold, the time threshold assigned to an area range to which the work area belongs.

10. The working unit is provided with a cutting blade for cutting grass, The target height is lower than the initial height, The working robot according to claim 4 , wherein the control unit, in the second height adjustment process, lowers a height of the working unit relative to the robot body from the initial height to the target height.

11. The working robot according to claim 2 , wherein the input unit includes a main body input unit provided on the robot main body.

12. a battery that is rechargeable and powers the work robot; The autonomous driving further includes a charging process of returning the work robot to a charging station to charge the battery, 12. The working robot according to claim 1, wherein, in the height adjustment process, the control unit changes a height of the working part relative to the robot body when the working robot is in the charging station, and does not change the height of the working part relative to the robot body when the working robot is not in the charging station.

Images