JP6743538B2 - Work robot - Google Patents

Description

The present invention relates to a work robot.

2. Description of the Related Art Conventionally, a device for cutting grass or lawn (referred to as a mowing (mowing, weeding) device (machine) or the like) has been used. Conventional brush cutters do not automatically perform drive control according to the state of grass or the like to be mowed, but drive control is manually performed by an operator.

Conventional brush cutters include a riding type and a wheelbarrow type. The riding type is a relatively large device that an operator gets in and drives, and is equipped with an engine and driven by gasoline or the like as fuel. The wheelbarrow type is equipped with an electric motor and is driven by electric power such as a battery.

Both types of brush cutters are configured so that the operator can manually set the driving conditions (such as the number of rotations of the motor) with reference to the presence/absence of grass, the degree of denseness, the hardness, etc. that can be visually determined. .. Therefore, if the operator's judgment is not appropriate, appropriate drive control is not performed. Also, when the driving condition is weak with respect to the state to be mowed (eg, the rotation speed is lower than appropriate), the operator cannot perform mowing, and thus tends to set excessive driving conditions (eg, rotation speed). The number is higher than appropriate). In this case, fuel and electric power are consumed more than necessary, which is not preferable.

The present invention has been made in view of the above, and an object of the present invention is to provide a work robot capable of drive control according to a state of a work (for example, mowing) target.

In order to solve the above-mentioned problems and to achieve the object, a work robot of the present invention has a working unit that performs a predetermined work involving load resistance by a driving force of a motor, and the working unit is moved along with the work. A drive unit, a reference setting unit that determines a plurality of reference values of load resistance that the motor can receive according to the environment in which the working unit is placed, and the motor is controlled based on the rotation speed or the current value of the motor. The load judgment means for judging the load resistance, the comparison means for comparing the judgment result of the load judgment means with the reference value defined by the reference setting means, and the drive of the motor according to the comparison result of the comparison means. And an output switching means for switching the force.

According to the present invention, there is an effect that drive control can be performed according to a state of a work (for example, mowing) target.

FIG. 1 is a diagram schematically showing the configuration of the brush cutter according to the first embodiment. FIG. 2 is a diagram showing the configuration and operation of the reaper. FIG. 3 is a block diagram showing the hardware configuration and functional configuration of the brush cutter together. FIG. 4 is a diagram showing a signal input/output state between the active control unit and the cooperating units. FIG. 5 is a diagram illustrating switchback mowing.

(First embodiment)
An embodiment of a work robot will be described in detail below with reference to the accompanying drawings. FIG. 1 is a diagram schematically showing the configuration of the brush cutter 1 according to the first embodiment. The brush cutter 1 is an example of a work robot.

The brush cutter 1 includes a main body 10, tires 11 to 14, a left drive gear 21, a right drive gear 22, a left driven gear 23, a right driven gear 24, a left timing belt 25, a right timing belt 26, a left drive motor 31, and a right drive motor 31. The drive motor 32, the reaper 40, the metal detectors 51 to 54, the sensors 61 to 66, the battery 70, and the controller 80 are provided.

The main body 10 is supported at its four corners by the tires 11 to 14, and moves by the rotation of the tires 11 to 14. Although the tires 11 to 14 are used in the present embodiment, in practice, instead of the tires 11 to 14, for example, endless tracks may be used.

The main body 10 includes a left drive gear 21, a right drive gear 22, a left driven gear 23, a right driven gear 24, a left timing belt 25, a right timing belt 26, a left drive motor 31, a right drive motor 32, a battery 70, and a controller. Contains 80 etc.

The left drive motor 31 and the right drive motor 32 are examples of drive units. The left drive gear 21 rotates by receiving the drive force generated by the left drive motor 31. The tire 11 is rotationally driven by the left drive gear 21. The right drive gear 22 rotates by receiving the drive force generated by the right drive motor 32. The tire 12 is rotationally driven by the right drive gear 22.

The left timing belt 25 transmits the rotation of the left drive gear 21 to the left driven gear 23. The left driven gear 23 rotates the tire 13. The right timing belt 26 transmits the rotation of the right drive gear 22 to the right driven gear 24. The right driven gear 24 rotates the tire 14.

FIG. 2 is a diagram showing the configuration and operation of the reaping unit 40. The mowing unit 40 is an example of a working unit. The mowing unit 40 includes cutters 41 to 44, a mowing motor 45, cams 46 and 47, and a rotary shaft 48. Each of the cutters 41 to 44 includes a plurality of mountain-shaped blades arranged in a horizontal row.

The cutter 41 and the cutter 42 function as a hair clipper by reciprocating in the opposite directions along the longitudinal direction while overlapping in the thickness direction. That is, the mowing unit 40 cuts the blade and the grass sandwiched between the blades. Similarly, the cutter 43 and the cutter 44 function as a hair clipper by reciprocating in the opposite directions along the longitudinal direction while overlapping in the thickness direction.

In addition, although the hair clipper type cutters 41 to 44 are adopted in this embodiment, other types of cutters such as a rotary type may be used in place of the cutters 41 to 44 in practice. Specific examples include a tip saw, a hammer knife mower, and a plastic resin blade.

The blades of the cutter 41 and the cutter 42 are directed to the front, and mow the grass when the brush cutter 1 moves forward. Further, the cutters 43 and 44 have their blades directed rearward and mow grass when the brush cutter 1 moves backward.

The cutter 41 and the cutter 43 are integrated on the opposite side (ridge) of the blade, and reciprocate together when the driving force of the reaping motor 45 is transmitted via the cam 46 and the rotating shaft 48. Similarly, the cutter 42 and the cutter 44 are integrated on the opposite side (peak) of the blade, and reciprocate together when the driving force of the reaping motor 45 is transmitted via the cam 47 and the rotary shaft 48.

The rotary shaft 48 transmits the driving force of the reaping motor 45 to the cam 46 and the cam 47. The cam 46 and the cam 47 receive the driving force of the reaping motor 45 via the rotary shaft 48 and transmit it to the cutters 41 to 44. The transmission is performed by the cam 46 and the cam 47 rotating in the links 43a and 44a of the cutter 43 and the cutter 44. The phase of the cam 46 in the link 43a and the phase of the cam 47 in the link 44a are provided to be shifted by 180°. As a result, the cutter 41 and the cutter 43 and the cutter 42 and the cutter 44 move in the left and right opposite directions.

The sensors 61 to 66 output signals corresponding to the pressure received by touching the grass. The sensor 61 is arranged in front of the main body 10. The sensor 62 is arranged behind the main body 10. The sensor 63 is arranged near the tire 11. The sensor 64 is arranged near the tire 13. The sensor 65 is arranged near the tire 14. The sensor 66 is arranged near the tire 12.

The metal detection parts 51 to 54 are arranged in four directions (front, rear, left and right) of the main body 10 and are used for detecting the metal wires 201 to 204 (described later, FIG. 5) stretched around the cutting range.

The battery 70 supplies electric power to the above-mentioned parts (the left drive motor 31, the right drive motor 32, the reaping motor 45, the metal detection parts 51 to 54, the sensors 61 to 66, and the control part 80).

FIG. 3 is a block diagram showing the hardware configuration and the functional configuration of the brush cutter 1 together. The brush cutter 1 includes a CPU (Central Processing Unit) 81, a ROM (Read Only Memory) 82, a RAM (Random Access Memory) 83, a cloud communication unit 84, a temperature/humidity sensor 91, a GPS (Global Positioning System) sensor 92, and a distance. A sensor 93, a grass presence sensor 94, current sensors 95 and 96, an encoder 97, motor drivers 98 and 99, and an active control unit 100 are provided.

The active control unit 100 includes a load determination unit 101, a comparison unit 102, an output switching unit 103, and a motor driver 104. The comparison unit 102 includes a grass presence/absence determination unit 102a. The active control unit 100 confirms the load resistance of the mowing motor 45 during mowing, and controls the mowing motor 45 to drive at a rotation speed suitable for the load resistance, thereby eliminating waste such as heat generation due to overload, Aim to save power. FIG. 4 is a diagram showing a signal input/output state between the active control unit 100 and each of the cooperating units.

The rotation speed criteria (1) to (4) input to the comparison unit 102 included in the active control unit 100 are the rotation speeds acquired by the cloud communication unit 84 illustrated in FIG. 3 from an external server or the like (hereinafter referred to as a cloud). It is a standard value.

The cloud stores in advance a database that summarizes the states of weeds that are predicted to grow depending on the region (seasonal condition, etc.), and the number of rotations (rotation number basis) that is suitable for the state of the weeds. Upon receipt of the request from the cloud communication unit 84, the cloud returns a rotation speed reference corresponding to the grass type and state in which overgrowth is estimated from the season and place as a response to the request.

The temperature/humidity sensor 91 measures temperature and humidity indicating the environment in which the brush cutter 1 is placed. The GPS sensor 92 identifies the place where the brush cutter 1 is placed, the traveling direction, and measures the moving distance. The outputs of the temperature/humidity sensor 91 and the GPS sensor 92 are used as additional information when the cloud communication unit 84 requests the cloud for the rotation speed reference.

Here, the cloud, the cloud communication unit 84, the temperature/humidity sensor 91, and the GPS sensor 92 function as an example of reference setting means.

The distance sensor 93 detects a distance to a cutting target such as grass. The grass presence/absence sensor 94 detects the presence/absence of grass (an example of a target presence/absence determining unit). Examples of the distance sensor 93 and the grass presence/absence sensor 94 include a method of measuring (distance measuring) a distance by infrared rays or ultrasonic waves, an image recognition method of estimating the distance from an image captured by a camera, and the like.

The current sensor 95 measures the value of the current flowing through the reaping motor 45. The current sensor 96 detects the rotation direction of the tires 11-14. The encoder 97 detects the rotation speeds and speeds of the tires 11-14.

The motor driver 98 controls driving of the left drive motor 31. The motor driver 99 controls driving of the right drive motor 32.

The ROM 82 is a read-only non-volatile storage medium, and stores in advance various programs executed by the CPU 81 and fixed data necessary for the execution.

The RAM 83 is a readable/writable volatile storage medium and stores temporary data. The RAM 83 is used as a work area when the CPU 81 executes a program.

The CPU 81 collectively executes the programs stored in the ROM 82 by using the RAM 83 as a work area, thereby centrally controlling each unit included in the brush cutter 1 to realize various functions.

The software control unit is configured by the CPU 81 performing calculation according to the program. The combination of the software control unit configured in this way and the hardware configures a functional unit that implements various functions of the brush cutter 1 according to the present embodiment.

The CPU 81, the ROM 82, and the RAM 83 constitute the control unit 80 and the active control unit 100. The control unit 80 centrally controls each unit of the brush cutter 1.

The motor driver 104 controls driving of the reaping motor 45. When controlling the reaping motor 45, the motor driver 104 controls the rotation speed so that the rotation speed changes within a predetermined range (movable range) with the rotation speed reference selected by the comparison unit 102 as the median value. The variable range is predetermined and stored in a predetermined storage unit, and is used in the comparison unit 102 and the like.

The load determination unit 101 is an example of load determination means. The load determination unit 101 determines the load of the reaping motor 45 from the current flowing through the reaping motor 45 obtained from the output of the current sensor 95 and the rotation speed of the reaping motor 45 obtained from the output of the encoder 97.

The load of the reaping motor 45 is a material for estimating the hardness and denseness of grass. When the load resistance of the mowing motor 45 is large because the grass is hard or dense, the current value of the mowing motor 45 increases and the rotation speed decreases. Further, the increase in load resistance causes heat generation of the reaping motor 45, but heat generation is not preferable because energy is wastefully consumed even if it does not lead to overheating or failure, so it is desirable to avoid it. The load determination unit 101 monitors the density and hardness of the grass in real time, and outputs the monitoring result to the functional unit on the downstream side for specific measures.

The comparison unit 102 is an example of comparison means. The comparison unit 102 compares a plurality of (four types here) rotation speed references acquired by the cloud communication unit 84 with the output of the load determination unit 101, and selects the most suitable rotation speed reference among the plurality of rotation speed references. Then, a PWM (Pulse Width Modulation) signal according to the selected rotation speed reference is output to the output switching unit 103.

The comparing unit 102 includes four comparators, and each of the comparators 1021 to 1024 has four kinds of stepwise rotation speed standards (clouds) corresponding to four kinds of weighting amounts (-1, 0, +1, +2). (Acquired via the communication unit 84) is set. The selection of the rotation speed reference is performed by selecting the comparators 1021 to 1024.

The rotation speed reference of which the weighting amount is “0” is a value (target value) which is considered to be most suitable for the grass type and state (withered state, etc.) in which the overgrowth is estimated from the season and place in the cloud.

The three types of rotation speed references other than the weighting amount “0” are set with a range depending on the weighting amount with reference to the target value. The rotation speed reference of the weighting amount “−1” is a value lower than the target value. The rotation speed reference of the weighting amount “+1” is a value higher than the target value. The rotation speed reference of the weighting amount “+2” is a value higher than the rotation speed reference of the weighting amount “+1”.

The grass presence/absence determination unit 102a of the comparison unit 102 compares the "grass presence reference value" with the output of the load determination unit 101 to determine the presence/absence of grass (an example of a target presence/absence determination unit), and an output switching unit. Output to 103. That is, the grass presence/absence determining unit 102a stops the rotation of the reaping motor 45 or determines the number of rotations when the output of the load determining unit 101 is compared with the “grass reference value” and it can be determined that there is no grass. To reduce power consumption.

The “grass-containing reference value” may be stored in the ROM 82 in advance, or may be acquired from the cloud by the cloud communication unit 84.

In addition, the execution judgment such as the control of the reaping motor 45 for the purpose of power saving according to the presence or absence of the grass described above is determined by the output of the distance sensor 93 (distance to the grass), the output of the grass presence sensor 94 (grass presence signal), Alternatively, it may be performed according to the detection result of the pressure (grass pressure) received from the grass by the sensors 61 to 66.

The output switching unit 103 is an example of an output switching unit. The output switching unit 103 outputs a motor speed variable signal to the motor driver 104 according to the output from the comparison unit 102. As a result, the cutting motor 45 is controlled according to the state of the cutting target such as grass.

Further, the output switching unit 103 outputs a speed instruction signal to the motor drivers 98 and 99 when receiving the low speed traveling instruction command or the high speed traveling instruction command. The above-described low speed traveling instruction command and high speed traveling instruction command are input from the CPU 81, for example.

An example of the operation of the brush cutter 1 having such a configuration will be described below. FIG. 5 is a diagram illustrating switchback mowing. In this example, the brush cutter 1 cuts grass in a cutting range surrounded by the metal wires 201 to 204.

However, the metal wires 201 to 204 are installed in consideration of the displacement of the installation positions of the metal detection units 51 to 54 and the cutting unit 40. That is, when the detection position of the metal detection units 51 to 54 is outside the cutting position by the cutters 41 to 44 as illustrated, the metal wires 201 to 204 are set to be slightly wider than the desired cutting range.

When any of the metal detection units 51 to 54 provided on the front, rear, left, and right sides of the main body 10 detects a metal, the control unit 80 determines that one of the metal wires 201 to 204 is detected and the own device cuts the range. It is judged to be located in the peripheral part of. Applying this, the control unit 80 starts from the state where the rear metal detection unit 52 and the metal detection unit 53 on one side detect metal in the switchback mowing of this example, and the metal detection state of the metal detection unit 53 starts. The main body 10 is moved forward while maintaining.

Next, the control unit 80 causes the main body 10 to move backward diagonally, triggered by the metal detection by the front metal detection unit 51. Due to this backward movement, metal detection on the side (by the metal detection unit 53) is eliminated. The cutters 41 to 44 are driven not only when moving forward but also when moving backward.

Here, with respect to the backward angle, when the rearward metal wire 202 is detected, the main body 10 moves to the right by a distance of, for example, about half of the mowing width (longitudinal dimension of the cutters 41 to 44). It is about an angle.

In this way, if the cutting range is flat, the cutters 41 to 44 will cut the same portion a plurality of times (2 to 3 times). However, by doing so, even if the mowing range is uneven, there is no portion where the cutters 41 to 44 do not pass regardless of the state, and it becomes possible to make it difficult to leave uncut.

Next, the control unit 80 advances the main body 10 in a direction parallel to the previous advance direction, triggered by the metal detection by the rear metal detection unit 52. By repeating this, the control unit 80 moves the main body 10 within the cutting range, while shifting the body 10 back and forth and gradually to the side.

Then, the control unit 80 detects metal on the side opposite to the side on which metal detection was performed at the start (by the metal detection unit 54) and detects metal on the rear side (or front side) (metal detection unit 51). Alternatively, the movement of the main body 10 is completed by the metal detection unit 52).

In the above example, the main body 10 was started from the left side of the cutting range, but it goes without saying that the main body 10 may be started from the right side and the cutting may be completed on the left side. In this case, the metal detection unit 54 is in charge of the side metal detection at the start, and the metal detection unit 53 is in charge of the side metal detection at the end.

In the autonomous traveling as described above, the brush cutter 1 controls the rotation of the cutting motor 45 and the moving speed of the main body 10 according to the state of the cutting target.

First, when the power of the brush cutter 1 is turned on, the CPU 81 starts up, and the GPS function by the GPS sensor 92 and the cloud communication unit 84 also start up. As a result, information can be collected from the GPS, and the position of the brush cutter 1 is specified based on the GPS information.

Further, since communication with the cloud is possible, the brush cutter 1 informs the cloud of information such as the position of the brush cutter 1 and the output of the temperature/humidity sensor 91. Based on the received information and the calendar information, the cloud that has received the information from the growth prediction information according to the type of the weeds and the season associated with the map information of the mowing area stored in the cloud in advance, and the mowing device 1 Estimate the grass type and season at the present location of. Then, as a response to the brush cutter 1, information (weighting information) such as a current value considered necessary for the reaping motor 45 and an optimal rotation speed reference is returned.

The CPU 81 causes the RAM 83 to store weighting information such as the current value and the rotation speed reference obtained from the cloud response, and further updates the four types of rotation speed reference in the comparison unit 102.

In the present embodiment, the optimum value such as the current value and the rotation speed is obtained by cloud communication, but the implementation is not limited to this. For example, the weighting information may be formed into a cassette for each mowing area and stored in a non-volatile memory (flash ROM or ROM) of the mowing device 1 in advance. According to this, it is possible to implement even in a place where the communication environment is not prepared.

When the CPU 81 finishes setting the weighting information in the comparison unit 102, it activates the motor drivers 98, 99, 104. At this point, the mowing device 1 is not performing mowing and the information on the first grass resistance has not been input, so the motor driver 104 sets the maximum value as the initial value of the rotation speed of the mowing motor 45. , Wait for input of start signal. At this time, the initial value of the rotation speed is set to the maximum value in order to prepare for a situation where the object to be mowed is hard or dense and receives high load resistance.

When the operator performs an operation such as pressing a start button provided on the main body 10, the CPU 81 recognizes that a start signal has been input, and instructs the motor drivers 98, 99, 104 to output the motor 31, 32. , 45 to start the operation.

Here, when the brush cutter 1 is operated by the RC (Radio Control: Radio Control) operation from the operator instead of the autonomous traveling as shown in FIG. 5, when the operation such as pressing the start button is performed, The brush cutter 1 is in a standby state for inputting an RC operation signal. Then, when the operator's RC operation transmitter (propo) transmits an operation signal, the reaping motor 45 starts driving at the maximum value according to the set value, and the main body 10 starts moving. In the case of RC operation, the brush cutter 1 continues the cutting operation until the operator sends a stop signal.

When the motors 31, 32, 45 start operating and mowing is carried out, information on the current and the number of rotations of the mowing motor 45 is fetched by the comparison unit 102. Then, the comparison unit 102 selects and sets the rotation speed reference according to the load on the reaping motor 45 (correction of the rotation speed).

After that, the CPU 81 compares the grass with the rotation speed reference with the comparison unit 102 while recognizing the grass existence state with the grass presence determination unit 102a based on the information obtained from the cutting motor 45 by executing the cutting, and the grass. The resistors are determined and the comparators 1021 to 1024 that are the center values of the weighting amounts are selected. Thereby, control according to the state of the reaping target can be performed.

The supplementary explanation of the above-mentioned judgment of grass resistance will be made. When the grass is soft, the current peak value is low, and when the grass is hard, the current peak value is high. In addition, when the grass density is low, the current per unit time when cutting the grass has a low value and the rotation speed is high. When the grass density is high, the current per unit time at the time of cutting grass is averaged to have a high value, and the rotation speed is low (the cutting motor 45 generates heat at this time). Based on each rotation speed standard set in consideration of these, the CPU 81 determines grass resistance in a gradational manner and selects a suitable comparator 1021 to 1024.

After selecting the comparators 1021 to 1024, the selected one is used as the center value of the weighting amount, and when the rotation speed of the reaping motor 45 exceeds the rotation speed reference of the selected comparators 1021 to 1024, the next highest rotation speed is obtained. Change the selection to a number-based one. Further, when the rotation speed of the reaping motor 45 falls below the rotation speed reference of the selected comparators 1021 to 1024, the selection is changed to the next lower rotation speed reference.

As described above, according to the present embodiment, it is possible to perform drive control according to the state of the mowing target. As a result, the battery 70 is not excessively consumed, and it is possible to prevent inconveniences such as overheating of the reaping motor 45 and heat generation.

Hereinafter, modified examples supplementing the above embodiment will be described.

(Modification 1)
Since the brush cutter 1 is moving during the mowing, the type and density of the grass around the brush cutter 1 change and are not constant. Therefore, the brush cutter 1 may go to a place where the type of grass or the density of grass is not suitable for the variable range of the rotation speed or the current based on the selected rotation speed reference.

When the grass is hard or dense and has a high load resistance, the cutting can be performed by increasing the time during which the cutters 41 to 44 contact the cutting target. Therefore, when the load resistance is high, the CPU 81 controls the traveling speed of the main body 10 so as to travel at a low speed of about 30% to 70% of the normal speed (control means). As a result, it is possible to mow while avoiding heat generation due to excessive load resistance (overload).

In the above case, not only the main body 10 travels at a low speed, but also the comparators 1021 to 1024 that increase the rotation speed of the reaping motor 45 in the comparison unit 102 are selected as described in the first embodiment. As a result, the amount of work of the cutters 41 to 44 per mowing target is increased, and mowing when the load resistance is high is facilitated.

(Modification 2)
When the number of rotations is significantly reduced during cutting (judging against a predetermined threshold value, for example, 10 rotations or less), cutting cannot be performed. In this case, the CPU 81 determines that grass is accumulated on the cutters 41 to 44, or grass or a foreign object is caught between the cutter 41 and the cutter 42 or between the cutter 43 and the cutter 44 (sliding part). to decide. Then, the CPU 81 retracts the moving body for removing the accumulated on the cutters 41 to 44, and then rotates the reaping motor 45 for a certain period of time (idling control) to remove foreign matter or grass caught in the sliding portion. Is removed (an example of clogging removal means) to reduce overload.

(Modification 3)
In the second modification, even if an attempt is made to rotate the reaping motor 45 in order to remove foreign matter or grass caught in the sliding portion, the sliding portion may not be moved and may not be removed depending on how it is caught or the degree of clogging. In this case, if the sliding portion is moved in a direction opposite to the normal moving direction, it is highly possible that the foreign matter caught in the sliding portion will fall and be removed. Therefore, the CPU 81 reversely rotates the reaping motor 45. Let

(Modification 4)
In Modifications 2 and 3, during driving for removing foreign matter, the CPU 81 monitors the rotation speed and current of the reaping motor 45 and continues rotation until the rotation speed and current values in the normal state are returned. To do. As a result, it is possible to improve the certainty of removing the clogging.

(Modification 5)
When the rotation speed and the current value do not return to the normal values even if the rotation continuation in the modified example 4 is performed for a certain period of time, the CPU 81 stops the cutting motor 45 in order to prevent the burnout motor 45 from being burned, and displays it via a predetermined display unit. Notify the operator of the reason for the stop. Here, the predetermined display unit is, for example, a display lamp provided on the main body 10. The indicator light is provided, for example, on the top of a pole that is mounted upright, and changes the color, lighting/extinguishing, blinking, or the like in accordance with the content of the notification.

(Modification 6)
When the brush cutter 1 is retracted as in the second modification, it is dangerous for an operator or a person to be present around the brush cutter 1. Therefore, the CPU 81 alerts the surroundings by sounding a sound or lighting an indicator light. Perform (an example of notification means).

(Modification 7)
If the measures of the above-mentioned Modifications 1 to 4 are overloaded (or the grass cannot be mowed or the clogging cannot be removed), the CPU 81 determines that the mowing is impossible, and stops or avoids the operation (excessive). An example of load prevention means). This protects the cutters 41-44. Here, the above-mentioned avoidance is, for example, to wrap around to the other side of a non-mowable part and restart mowing.

(Modification 8)
When the CPU 81 determines that there is no cutting target such as grass, the CPU 81 causes the traveling speed of the main body 10 to travel faster than normal (for example, about 1.3 to 10 times the normal speed) in order to reduce the working time.

At this time, the rotation of the reaping motor 45 may be stopped in order to reduce the power consumption. Alternatively, in case the grass appears during running, for example, the mowing motor 45 is rotated at a very low speed, and if there is a sudden change in the rotation or the current of the mowing motor 45, it is determined that the grass has appeared and the mowing is performed. It may be started.

(Modification 9)
In the modified example 8, when power consumption is suppressed by stopping the mowing motor 45, the presence or absence of grass can be determined from the pressure detected by the sensors 61 to 66 (an example of a target presence/absence determining unit).

(Modification 10)
In the above-described embodiment, the cutting range is indicated by the metal wires 201 to 204, but in practice, for example, by using the laser or high-frequency sound, the cutting instrument 1 is guided to cut the cutting range within a predetermined range. May be realized.

As described above, according to the above-described embodiment and modification, by feeding back the state of the mowing object to the control circuit of the mowing motor 45, the rotation speed reference is selected in accordance with the state of the grass and the selected rotation is selected. It is possible to control the reaping motor 45 so that the rotation speed is substantially constant according to the number standard. And thereby, it becomes possible to suppress the heat generation of the reaping motor 45 and the reduction of work efficiency to the minimum.

Generally, mowing work such as grass is performed multiple times throughout the year, but depending on the place where the mowing device 1 is placed and the operating condition (temperature, humidity, etc.), the condition of the mowing target such as grass is predicted. By selecting the driving condition (rotation speed reference), the reaping motor 45 can be driven under the optimum driving condition according to the type of grass and the state of grass withering due to the season or region. As a result, high efficiency can be achieved from the viewpoint of power saving, and the duration of the battery 70 can be extended.

DESCRIPTION OF SYMBOLS 1... Mowing device 10... Main body 11-14... Tire 31... Left drive motor 32... Right drive motor 40... Mowing parts 41-44... Cutters 43a, 44a... Link 45... Mowing motors 51-54... Metal detection part 61- 66... Sensor 70... Battery 80... Controller 81... CPU
82... ROM
83... RAM
84... Cloud communication unit 91... Temperature/humidity sensor 92... GPS sensor 93... Distance sensor 94... Grass presence sensor 95... Current sensor 96... Current sensor 97... Encoder 98... Motor driver 99... Motor driver 100... Active control unit 101... Load Judgment unit 102... Comparison units 1021 to 1024... Comparator 102a... Grass presence/absence judgment unit 103... Output switching unit 104... Motor drivers 201-204... Metal wires

JP, 10-320045, A JP 2012-244953 A Japanese Patent No. 5777855

Claims (11)

A work unit that performs predetermined work with load resistance by the driving force of the motor,
A drive unit for moving the working unit along with work,
Reference setting means for determining a plurality of reference values of load resistance that the motor can receive according to the environment in which the working unit is placed,
Load determining means for determining the load resistance carried by the motor based on the rotation speed or the current value of the motor,
Comparing means for comparing the judgment result of the load judging means with the reference value set by the reference setting means;
Output switching means for switching the driving force of the motor according to the comparison result of the comparison means,
A work robot equipped with. And a control unit that switches the moving speed of the working unit by the driving unit to a low speed when the load resistance determined by the load determining unit is higher than a predetermined reference value by the comparing unit. The work robot according to claim 1, wherein: When the load resistance determined by the load determination unit is lower than a predetermined reference value by the comparison unit, the control unit further includes a control unit that switches a moving speed of the working unit by the drive unit to a high speed. The work robot according to claim 1 or 2. Further comprising a target presence/absence determining means for determining the presence/absence of a work target of the working unit,
The control means for switching the moving speed of the working unit by the drive unit to a high speed when the target presence/absence determining unit determines that there is no work target is further included. The work robot described in the item. The work robot according to claim 4, wherein the control unit stops or rotates the motor at a low speed when the target presence/absence determining unit determines that there is no work target. When the load resistance determined by the load determining unit is higher than the maximum reference value by the comparing unit, the drive unit and the working unit are controlled to stop or avoid the work at the current location. The work robot according to any one of claims 1 to 5, further comprising an overload prevention unit that performs When the load resistance determined by the load determining means is higher than a first threshold value, a clogging removing means is provided for performing a slipping control for driving the motor while retracting the working portion with respect to the drive portion. The work robot according to claim 1, further comprising: a work robot. When the clogging removal means performs the idling control and determines from the output of the load determination means that the motor is not driven or the load resistance is higher than the second threshold value, The work robot according to claim 7, wherein the motor is rotated in a reverse direction. 9. The work robot according to claim 8, wherein the clogging removing unit ends the reverse rotation of the motor when the load resistance of the motor falls below the second threshold value from the output of the load determining unit. 10. The work robot according to claim 7, further comprising a notifying unit for notifying the surroundings of the retreat of the working unit. The object presence determination means, work according to claim 4, characterized in that the distance measurement to the work object, by detecting the pressure from the working image recognition of the target, or a work object, and determines the presence or absence of said work object robot.

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