JP2008090756A - Mobile robot - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile robot securing safety immediately after starting moving when it is rain. <P>SOLUTION: The mobile robot, moving on an outdoor road surface by a moving means, includes a detection section for detecting through a detection window the information of an obstacle having a risk of impediment to running, a water drop removal section for removing water drops attached to the detection window by blowing air on the detection window of the detection section, a road surface condition detection section for detecting a wet condition of the road surface, and a control section for deciding the start of moving control based on either a schedule stored in advance or an external signal input. When it is decided to be the start of the moving control, the above control section controls to start the movement by the moving means when the road surface condition detection section does not decide a wet road surface. When a wet road surface is decided, the control section controls to operate the water drop removal section, and after the lapse of a predetermined time from the start of the above operation, starts the movement by the moving means. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a mobile robot that travels outdoors while detecting surrounding environmental information, and more particularly to a mobile robot that removes water droplets attached to a sensor that detects environmental information around or in the moving direction of the mobile robot.

  In recent years, various mobile robots that autonomously move on a road surface while detecting an obstacle outdoors using a battery as a driving source have been put into practical use. As such a mobile robot, an obstacle sensor that receives a reflected return signal from an object as a detection signal by irradiating various exploration signals such as a laser beam, a visible ray, an ultrasonic wave, and an infrared ray is provided. Is known to detect obstacles around it.

As such a mobile robot, the applicant travels around an outdoor monitoring area, scans the surroundings with a laser sensor (ranging sensor) based on laser projection and reception, and reflects the laser light reflected on the surface of an object existing in the surroundings. A mobile robot that receives light and detects the relative position of an obstacle has been proposed (Patent Document 1).
JP 2006-252346 A

  However, the mobile robot disclosed in Patent Document 1 has a problem in that a distance measuring sensor that detects an obstacle does not take measures against a drop in detection accuracy due to water droplets in rainy weather.

If water droplets adhere to the light projecting / receiving surface of the distance measuring sensor due to rain or water splashing from the water pool, the water droplets may cause light refraction or irregular reflection on the surface of the light projecting / receiving surface.
As a result, the laser light projected from the distance measuring sensor is reflected by the water droplets on the light projecting / receiving surface and received by the sensor as it is, or is refracted by the water droplets on the light projecting / receiving surface and is in an unexpected direction. This causes problems such as being irradiated. In the former case, it may cause a misjudgment that there is an obstacle at a close distance, and in the latter case, the obstacle cannot be detected in the original laser beam irradiation direction, which may result in a so-called false alarm. In either case, there is a problem in securing safety during movement.

  Therefore, as a countermeasure, it is conceivable to remove water droplets adhering to the light projecting / receiving surface of the laser beam by using a water droplet removing means by a blower such as an air blower. However, it takes a certain amount of time to remove water droplets by blowing air, and it is difficult to instantaneously remove water droplets. For this reason, immediately after the start of the movement in rainy weather, even if the water droplet removing means is operated, the water droplet adhering at the time of the stop is not immediately removed, and safety immediately after the start of the movement cannot be ensured. There is a problem. Further, in a mobile robot that is powered by a battery and repeatedly moves and stops, there is also a problem that the battery is significantly consumed when the water droplet removing means is always operated.

  In order to solve such a problem, the present invention makes it possible to remove water droplets adhering to a detection means such as a distance measuring sensor, and in particular, ensures safety even immediately after the start of movement and consumes battery power. The purpose is to provide a mobile robot that can be controlled.

  In order to achieve the above object, a mobile robot according to the present invention is a mobile robot that moves on an outdoor road surface by a moving means, and detects detection of obstacle information that may interfere with traveling through a detection window. A water droplet removing unit that removes water droplets attached to the detection window by blowing air to the detection window of the detection unit, a road surface state detection unit that detects the wet state of the road surface, a schedule stored in advance or from the outside A control unit that determines the start of movement based on a signal input, and when the road surface state detection unit does not determine that the road surface is wet when the control unit determines that the movement starts, the moving unit When the road surface is determined to be wet, the water drop removing unit is activated, and after the predetermined time has elapsed since the activation, the movement means starts the movement. It is characterized in that.

  When the road surface is wet, even if it is not raining, water droplets adhere to the detection window due to water vapor, and the detection accuracy decreases. Therefore, the mobile robot of the present invention detects the wetness of the road surface and operates the water drop removing unit when the road surface is wet. When starting to move, when it is detected that the road surface is wet, the water droplet removing unit is operated and the movement start by the moving means is delayed for a predetermined time.

  This makes it possible to operate the water drop removal unit not only during rain but also in situations where water droplets adhere to the detection window due to water vapor, and in situations where water droplets can adhere, the start of movement is delayed. It is possible to ensure the immediate safety.

  In the mobile robot according to the present invention, it is preferable that the control unit detects that an obstacle is detected in the vicinity of the detection window when the predetermined time has elapsed. And start of movement is prohibited.

  As a result, it is possible to detect erroneous detection of the detection unit due to factors other than water droplets, and by prohibiting movement in such a case, it is possible to further ensure safety.

  Furthermore, in the mobile robot according to the present invention, preferably, the road surface state detection unit detects a wet state of the road surface when moving on the road surface by the moving unit, and the control unit includes the moving unit. If the wetness of the road surface is determined while moving on the road surface, the water droplet removing unit is operated. If the wetness of the road surface is not determined, the operation of the water droplet removing unit is stopped.

  When the mobile robot is moving on the road surface, the mobile robot operates the water droplet removal unit according to the wetness of the road surface, and stops the operation. As a result, it is possible to prevent the water drop removing unit from operating more than necessary, and to suppress power consumption.

  In the mobile robot according to the present invention, preferably, the control unit stops the operation of the water droplet removing unit when the movement by the moving unit is stopped.

  When the mobile robot is stopped, it is not necessary to detect obstacles by the detection unit to ensure traveling safety. In this case, the operation of the water droplet removal unit may be stopped. As a result, it is possible to prevent the water drop removing unit from operating more than necessary, and to suppress power consumption.

  According to the mobile robot of the present invention, the water drop removing unit is provided to prevent the detection unit from deteriorating the detection accuracy, and the movement can be started after removing the water droplets, ensuring safety immediately after the start of the movement. can do.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
FIG. 1 is a schematic diagram showing a monitoring system using a mobile robot according to the present invention.
The mobile robot 1 is used to guard the monitoring area 3 that is the outer periphery of the building 7, and detects an abnormality in the monitoring area 3 while traveling around a guide 6 installed on the road surface of the monitoring area 3. Is.

  The mobile robot 1 is wirelessly connected to the monitoring center 2 and is stopped at the reference position 4 in the monitoring area 3. The mobile robot 1 is in the monitoring area 3 according to its own stored schedule or a movement signal received from the monitoring center 2. Start moving. Then, the mobile robot 1 transmits a surrounding image, an abnormal location, and the like to the monitoring center 2.

  In FIG. 1, the periphery of the building 7 is a moving route for the mobile robot 1 to circulate, and a guide 6 is fixedly provided over the entire length of the moving route. The guide 6 is made of a magnetic material, and the mobile robot 1 moves along the movement path along the guide 6 while detecting the guide 6 with a magnetic sensor described later.

  A reference position 4 having a charging facility for charging the battery of the mobile robot 1 is disposed in the middle of the guide 6. The mobile robot 1 starts moving from the reference position 4 and circulates on the guide 6. When the mobile robot 1 reaches the reference position 4, the movement ends and stops.

  The monitoring center 2 is a facility equipped with a center device 20 operated by a security company or the like, and a monitoring person monitors the monitoring area 3 by information transmitted from the mobile robot 1 via the communication network 8 and the wireless base station 9. is doing. However, the present invention is not limited to this, and the monitoring center 2 may be provided in a facility where guards are stationed in the building 7 in the monitoring area 3, for example, a disaster prevention center.

The center device 20 is a computer including a display unit 21 configured with a liquid crystal monitor, a CRT, and the like, an input unit 22 configured with a keyboard, a joystick, a pointing device, a speaker 23, a microphone 24, a CPU, and the like. And a control unit 25 configured to control the center device 20.
The display unit 21 displays position information of the mobile robot 1, an image taken by the mobile robot 1, information on an abnormality detected by the mobile robot 1, and the like. The input unit 22 is operated by a monitor to input predetermined commands and information. The control unit 25 expands the signal received from the mobile robot 1 and outputs it to the display unit 21 and the speaker 23, and moves the control signal based on the command input from the input unit 22 and the voice signal input from the microphone 24. Transmit to the robot 1.

The monitoring center 2 transmits a voice acquisition signal to the mobile robot 1 based on an image received from the mobile robot 1 and an abnormality signal, and receives a voice signal that the mobile robot 1 collects and transmits. And output from the speaker 23. Further, if necessary, the voice of the supervisor is captured by the microphone 24 and transmitted to the mobile robot 1, and the mobile robot 1 informs and outputs to the outside so as to have a conversation with persons around the mobile robot 1.
In the monitoring center 2, the monitoring person confirms whether or not there is an abnormality based on various information received from the mobile robot 1, and when the presence of the abnormality is recognized, a control signal is transmitted to the mobile robot 1 to deal with the abnormality.

Next, the configuration of the mobile robot will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the mobile robot.
The mobile robot 1 includes a control unit 31, a communication unit 32, a magnetic sensor 33, a moving unit 34, a storage unit 35, an imaging unit 36, a microphone 37, a speaker 38, a wetness detection unit 39, a distance measuring sensor unit 40, and an air pump 41. It is prepared for.

The control unit 31 is realized by a CPU, a memory, and the like, and controls each unit of the mobile robot 1 according to various programs stored in the memory. Various programs are executed in parallel as necessary. In addition, the control unit 31 includes a clock means and keeps the current time.
The communication unit 32 is a wireless communication unit that transmits and receives signals to and from the monitoring center 2 via the wireless base station 9 and the communication network 8. The communication unit 32 transmits a signal output from the control unit 31 to the monitoring center 2, demodulates the signal received from the monitoring center 2, and inputs the demodulated signal to the control unit 31.

  A magnetic sensor 33 is disposed at the bottom of the mobile robot 1, detects the guide 6 described above, and outputs a signal to the control unit 31. The moving means 34 includes wheels provided on the left and right sides of the vehicle body and motors that drive the wheels. The mobile robot 1 travels so as to follow the guide 6 by independently driving any of the front and rear left and right wheels.

  The storage unit 35 stores a traveling schedule transmitted from the monitoring center 2. The traveling schedule stores the movement start time of the mobile robot 1. When the current time reaches the movement start time stored in the patrol schedule, the control unit 31 controls the moving means 34 to start the movement of the mobile robot 1 and circulate the monitoring area 3. The storage unit 35 stores a rain flag. The rain flag is a flag that is turned ON when road wetness is detected by the wetness detection unit 39 described later, and is a flag that manages whether or not it is raining.

  An imaging unit 36 capable of imaging the entire periphery is provided on the upper body of the mobile robot 1. The mobile robot 1 transmits an image captured by the imaging unit 36 to the monitoring center 2 from the communication unit 32 while traveling around the monitoring area 3. In the monitoring center 2, a monitoring person monitors an image transmitted from the mobile robot 1 and confirms a situation around the mobile robot 1, a suspicious object, and an obstacle.

  A microphone 37 and a speaker 38 are provided on the front surface of the vehicle body of the mobile robot 1. The microphone 37 collects surrounding sounds and outputs the obtained sound signals to the control unit 31. When receiving the voice acquisition signal from the monitoring center 2, the control unit 31 transmits the voice signal collected by the microphone 37 to the monitoring center 2. The speaker 38 outputs an audio signal received from the monitoring center 2 or a warning sound stored in advance.

  A wetness detection unit 39 as a road surface state detection unit is provided on the front surface of the vehicle body of the mobile robot 1. The wetness detection unit 39 is a reflective optical sensor installed toward the road surface, and detects wetness of the road surface by reducing the reflected light when the road surface gets wet due to rain. That is, when the road surface is wet, the light emitted from the wetness detection unit 39 is irregularly reflected on the road surface, and the reflected light received by the wetness detection unit 39 is dimmed. The wetting detection unit 39 compares the irradiation output with the reflected light and determines that the road surface is wet when the reflected light is dimmed below a predetermined threshold.

  The wetness detection unit 39 is not limited to the reflection type optical sensor, and may be realized by other means as long as it detects the wetness of the road surface. For example, it may be a means for analyzing the image captured by the image unit 36 and determining the wetness of the road surface. For example, when the road surface is wet, the means for determining the wetness of the road surface by image analysis is based on the fact that the change in luminance when light is irradiated on the road surface is greater than that when the road surface is dry. Judge the wetness of.

  Two distance measuring sensor units 40 are provided on the lower side of the front of the vehicle body of the mobile robot 1. FIG. 3 shows an arrangement of each part on the front surface of the main body of the mobile robot 1 and a schematic diagram of the distance measuring sensor unit 40. The distance measuring sensor unit 40 is a case body in which a light projecting portion 43a, a light receiving portion 43b, and a blower nozzle 44, which are detection windows of the distance measuring sensor 43, are integrally arranged.

The distance measuring sensor 43 functions as a detection unit for detecting the relative position of an obstacle that may interfere with the traveling of the mobile robot 1 as environmental information. The distance measuring sensor 43 uses the outer surface (projecting / receiving surface) of the light projecting unit 43a and the light receiving unit 43b as a detection window, and detects information relating to the obstacle through this detection window. The distance measuring sensor 43 projects a detection signal based on a laser beam from the light projecting unit 43a, and receives a reflection regression signal from an obstacle at the light receiving unit 43b. The distance measuring sensor 43 calculates the relative distance from the distance measuring sensor 43 to the obstacle based on the time from the detection signal irradiation to the reflection regression signal detection, calculates the relative position of the obstacle based on this, and the control unit 31. Output to. When the relative position of the obstacle is input, the control unit 31 controls the moving unit 34 to perform processing such as stop of movement, acceleration / deceleration, and obstacle avoidance.
The distance measuring sensor 43 may be based on a method other than the above, and is configured to detect an obstacle with various sensors such as a visible ray, an ultrasonic wave, an infrared ray, and a millimeter wave radar type. Also good. Further, the calculation of the relative distance and the relative position based on the reception of the reflected regression signal may be realized by the control unit 31.

  The blowing nozzle 44 exposes the opening end 44a to the outside of the distance measuring sensor unit 40 and directs the opening end 44a toward the light projecting portion 43a of the distance measuring sensor 43 and the outer surface (light projecting / receiving surface) of the light receiving portion 43b. It is fixed to the unit 40. The base end side 44 b of the blower nozzle 44 is connected to the flexible tube 45 inside the distance measuring sensor unit 40, and is connected to the air pump 41 via the flexible tube 45. The air pump 41 is a blower source to the blower nozzle 44. The air pump 41 is activated by a control signal from the control unit 31, sucks outside air, compresses it, and blows compressed air to the flexible tube 45. The air blowing means including the air pump 41, the flexible tube 45, and the air blowing nozzle 44 functions as a water droplet removing unit.

Needless to say, the mobile robot 1 has a configuration for achieving the function as an autonomous mobile robot in addition to the above configuration. That is, the mobile robot 1 includes a resolver that detects the rotation amounts of the motor rotation shafts of both the left and right wheels, a position calculation unit that calculates a travel distance and a turning angle of the mobile robot from the output of the resolver, and calculates a current position. A battery for supplying In addition to the above-described tour schedule information, the storage unit 35 also stores information on a travel route in which a stop position and the like are stored, and information on the current position.
In FIG. 2, for the sake of explanation, each unit is described independently of the control unit 31, but those whose functions can be realized by computer processing may be realized by a computer of the control unit 31.

Next, the operation of the mobile robot of this embodiment will be described.
The outline of the operation is as follows. When the mobile robot 1 transitions from the stop state to the start of movement and detects that the road surface is wet, the mobile robot 1 delays the start of movement for a predetermined time, and drops the water droplet removal unit (air pump 41, flexible tube 45). The water droplets on the light projecting / receiving surface of the distance measuring sensor 43 are removed by the blower nozzle 44). Then, the movement starts after a predetermined time has elapsed. At this time, once wetting of the road surface is detected, the water drop removing unit is continuously operated during movement to ensure traveling safety. When the movement stops, the operation of the water drop removing unit is stopped to suppress battery consumption. And when changing to a movement start again, a movement start is similarly delayed according to the detection condition of a wet road surface, and a water drop removal part is started.

Hereinafter, the operation of the mobile robot will be specifically described with reference to FIG.
FIG. 4 is a flowchart showing the operation of the water droplet removal unit of the mobile robot in the first embodiment. The mobile robot 1 stops at the reference position 4 and stands by in a state where the battery is charged by the charging facility. In this state, the mobile robot 1 starts the process of FIG. 4 when the power is turned on or when a predetermined time before the movement start time stored in the storage unit 35 comes.

  First, the mobile robot 1 operates the wetness detection unit 39 to determine whether or not the road surface ahead is wet, and prepares for the start of movement (step ST1). If the road surface is wet, the rain flag (initial value is OFF) in the storage unit 35 is set to ON (step ST2). Then, it is determined whether or not to start moving based on whether or not the movement start time has arrived and whether or not a movement signal has been received from the monitoring center 2 (step ST3). When the movement start time is reached or a movement signal is received from the monitoring center 2, it is determined that movement is started (step ST3-Yes).

  When the start of movement is determined, the state of the rain flag in the storage unit 35 is confirmed (step ST4). If the rain flag is ON (the road surface is wet) (step ST4-Yes), the air pump 41 is activated to inject compressed air from the blower nozzle 44 (step ST5), and time counting for a predetermined time is started (step ST5). Step ST6). When the time has reached a predetermined time (step ST7-Yes), the process proceeds to step ST8. Here, the predetermined time measured when the air pump 41 is started is a time required for removing water droplets adhering to the light projecting / receiving surface of the distance measuring sensor 43 by blowing air from the blowing nozzle 44. In the embodiment, it is 10 seconds.

On the other hand, if the rain flag is OFF (the road surface is not wet) in step ST4 (step ST4-No), the process proceeds to step ST8 without starting the air pump 41.
In step ST8, the control unit 31 determines whether or not the distance value detected by the distance measuring sensor 43 indicates a distance near the sensor, that is, whether or not an object close to the distance measuring sensor 43 is detected. If a proximity object is detected (step ST8-Yes), it is determined that the distance measuring sensor 43 is abnormal (step ST9). When the abnormality of the distance measuring sensor 43 is determined, the control unit 31 transmits an abnormality signal to the monitoring center 2 and prohibits the start of movement.

  On the other hand, if the distance measuring sensor 43 has not detected a proximity object (step ST8-No), the control unit 31 drives the moving means 34 to start the movement of the mobile robot 1 along the movement path, and The patrol is started (step ST10).

Thus, if the mobile robot 1 determines the start of movement in a situation where the road surface is wet, the mobile robot 1 activates the air pump 41 and removes water droplets attached to the distance measuring sensor 43 before starting the movement. Then, the start of the movement is delayed for a predetermined time, and after the water droplets adhering to the distance measuring sensor 43 are removed, the movement means 34 is driven to start the movement of the movement path.
As a result, the reliability of the distance measuring sensor 43 immediately after the start of movement in rainy weather can be improved, and the driving safety can be improved.

  When starting to move, the mobile robot 1 checks the state of the rain flag (step ST11). In the present embodiment, when the wetness of the road surface is detected and the rain flag is set to ON, the air pump 41 continues to operate while moving on the route thereafter. Here, if the rain flag is ON in step ST11 (step ST11-Yes), the wetness of the road surface has already been determined and the air pump 41 is also in operation (for example, steps ST4 and ST5). Proceed with the process.

  On the other hand, if the rain flag is OFF (step ST11-No), it is determined whether or not wetting of the road surface is detected by the wetting detection unit 39 (step ST13). If wetting of the road surface is not detected (step ST13-No), the process proceeds to step ST12 without starting the air pump 41.

  On the other hand, when it is detected that the road surface is wet (step ST13-Yes), the rain flag is set to ON (step ST14), the air pump 41 is activated and the compressed air is injected from the blow nozzle 44 (step ST14). ST15).

  In step ST12, the mobile robot 1 determines whether to stop moving. When the current position is a stop position set in advance on the route, or when the distance measuring sensor 43 detects an obstacle, the control unit 31 determines to stop the movement (step ST12—Yes). Similarly, when a stop signal is received from the monitoring center 2, the movement is stopped in the same manner. When it is determined that the movement is stopped, the control unit 31 stops the movement of the mobile robot 1 in step ST16.

  When the movement of the mobile robot 1 is stopped, the control unit 31 determines whether or not the movement on the route is completed, that is, whether or not the reference position 4 has been reached in step ST17. If the movement on the route has not ended (step ST17-No), the state of the rain flag is determined (step ST18). If the rain flag is ON (step ST18-Yes), the operation of the air pump 41 is stopped (step ST19), and the process returns to step ST1. If it is determined again in step ST3 that the movement is started, the air pump 41 is activated according to the state of the rain flag (step ST5), and the movement start is delayed for a predetermined time (step ST7).

As described above, when the mobile robot 1 temporarily stops moving in a situation where the road surface is wet, the air pump 41 is stopped to prevent the battery from being consumed, and the mobile robot 1 starts moving again. Then, the air pump 41 is activated to remove water droplets adhering to the distance measuring sensor 43. Then, the start of the movement is delayed for a predetermined time, and after the water droplets adhering to the distance measuring sensor 43 are removed, the movement means 34 is driven to start the movement of the movement path.
As a result, unnecessary battery consumption can be suppressed, and the reliability of the distance measuring sensor 43 immediately after the start of movement in rainy weather can be improved to improve traveling safety.

  On the other hand, if it is determined in step ST17 that the movement on the route is finished, that is, if it is determined that the vehicle has arrived at the reference position 4 (step ST17-Yes), the process proceeds to step ST20. Then, the state of the rain flag is discriminated (step ST20). If the rain flag is ON, the operation of the air pump is stopped (step ST21), the rain flag is set to OFF (step ST22), and the process is terminated. And start charging the battery.

Next, a second embodiment of the mobile robot of the present invention will be described with reference to FIG.
FIG. 5 is a flowchart showing the operation of the water droplet removal unit of the mobile robot in the second embodiment. In the following, the description will focus on the parts different from the first embodiment according to FIG. 4 described above, and the description of the first embodiment will be used for the same parts as the first embodiment, and the description will be omitted.

  This embodiment is different from the first embodiment described above in that the wet flag detection unit 39 rewrites the rain flag ON / OFF setting every time the wet road surface detection process is performed. As shown in FIG. 5, the mobile robot 1 determines whether the road surface is wet (step ST51). If the road is not wet, the rain flag is set to OFF (step ST52). A rain flag is set to ON (step ST53).

  When the movement start time is reached or the movement start is determined by receiving a movement signal from the monitoring center 2 (step ST54-Yes), the state of the rain flag is determined (step ST55). If the rain flag is ON (step ST55-Yes), the air pump 41 is activated and compressed air is blown from the blowing nozzle 44 (step ST56), and time measurement for a predetermined time is started (step ST57). When the time reaches a predetermined time (step ST58-Yes), the output result of the distance measuring sensor 43 is determined. If the distance measuring sensor 43 has detected a proximity object (step ST59-Yes), it is determined that the distance measuring sensor 43 is abnormal (step ST60). On the other hand, if the distance measuring sensor 43 has not detected a proximity object (No in step ST59), the control unit 31 drives the moving unit 34 to start moving the mobile robot 1 along the moving path (step ST61). .

When starting to move, the mobile robot 1 determines whether or not the wetness of the road surface is detected by the wetness detection unit 39 (step ST61). When the wetness of the road surface is detected (step ST62-Yes), the rain flag is set to ON (step ST63), the air pump 41 is activated and the compressed air is blown from the blowing nozzle 44 (step ST64), and step ST65. Continue the process.
In the process from step ST62 to ST64, if the air pump 41 has already been operated according to the past determination result (for example, step ST56), the process of step ST64 is skipped and the process proceeds to step ST65.

On the other hand, when the wetness of the road surface is not detected in step ST62 (step ST62-No), the rain flag is set to OFF (step ST66). If the air pump 41 is operating, the air pump 41 is stopped (step ST66). (ST67) and the process proceeds to step ST65.
If the air pump is already stopped (rain flag is OFF) as a result of the past determination in the processes related to steps ST66 and ST67, the process of step ST67 is skipped and the process proceeds to step ST65.

  Thus, in this embodiment, the air pump 41 is operated only when the wetness of the road surface is detected. Accordingly, it is possible to prevent consumption of the battery and further reduce power consumption.

In step ST65, the control unit 31 determines whether the movement of the mobile robot 1 is stopped (step ST65-Yes), and when the mobile robot 1 stops moving (step ST68), it is determined whether the movement on the route is completed. (Step ST69). If the movement on the route has not ended (step ST69-No), the state of the rain flag is determined. If the rain flag is ON, the operation of the air pump 41 is stopped (steps ST70 and ST71), and step ST51. Return processing to.
And a rain flag is suitably set according to the wet state of the road surface detected while stopping. If the start of movement is determined again in step ST54, the air pump 41 is activated according to the state of the rain flag (step ST56), and the start of movement is delayed for a predetermined time (step ST58).

  In step ST69, when it is determined that the movement on the route is completed (step ST69-Yes), the state of the rain flag is determined. If the rain flag is ON, the operation of the air pump 41 is stopped (step ST69). (ST72, ST73), the rain flag is set to OFF (step ST74), the processing is terminated, and charging of the battery is started.

  In this way, in this embodiment, the mobile robot 1 switches the start / stop of the air pump 41 by rewriting the rain flag ON / OFF setting every time the wetness detection unit performs the wet road surface detection process. That is, when the wetness of the road surface is detected, the air pump 41 is operated to remove water droplets adhering to the distance measuring sensor 43, and when the road surface is not wet, the air pump 41 is stopped. Thereby, in addition to the effect of 1st embodiment mentioned above, it becomes possible to further suppress unnecessary battery consumption.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiment, and the above-described embodiment can be modified by appropriately combining the following modifications. A modification of the embodiment will be described below.

In each of the embodiments described above, an example in which water droplets attached to the distance measuring sensor are removed by the water droplet removing unit has been described. However, the present invention is not limited to this, and water droplets attached to an imaging unit that acquires image information serving as environmental information. It is good also as a structure which removes. That is, the imaging unit is a detection unit that detects image information as surrounding environmental information, and if water droplets are attached to the imaging lens serving as the detection window, the detection accuracy of the environmental information decreases. For this reason, it is good also as a structure which removes the water droplet of an imaging lens in a water droplet removal part.
In this case, the blowing nozzle is fixed to the imaging unit with the opening end of the blowing nozzle facing the imaging lens. Then, as described above, the air pump is started / stopped by the control signal of the control unit, and the compressed air is injected toward the imaging lens.

  Further, in each of the embodiments described above, the rain flag is set according to the wet state of the road surface detected by the wetness detection unit. However, the present invention is not limited to this, and rain is detected instead of the wetness detection unit. It is possible to detect whether or not it is raining by providing a simple sensor means, and to set the rain flag as a result. That is, if it is detected that it is raining, the rain flag is set to ON. Various sensor means for detecting rain are already known. For example, by analyzing an image picked up by an image pickup unit, it is determined that it is raining when a linear component repeatedly appears and disappears due to a difference between frames. Can be realized.

Schematic showing a monitoring system using a mobile robot according to the present invention Block diagram showing the configuration of the mobile robot Schematic configuration diagram of ranging sensor unit The flowchart which shows operation | movement of the water droplet removal part of the mobile robot in 1st embodiment. The flowchart which shows operation | movement of the water drop removal part of the mobile robot in 2nd embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mobile robot 2 Monitoring center 3 Monitoring area 4 Reference position 6 Guide 7 Monitoring area building 8 Communication network 9 Radio base station 20 Center apparatus 21 Display part 22 Input part 23 Monitoring center speaker 24 Monitoring center microphone 25 Control of center apparatus Unit 31 Mobile Robot Control Unit 32 Communication Unit 33 Magnetic Sensor 34 Moving Means 35 Storage Unit 36 Imaging Unit 37 Mobile Robot Microphone 38 Mobile Robot Speaker 39 Wet Detection Unit 40 Distance Sensor Unit 41 Air Pump 43 Distance Sensor 43a Measurement Light emitting portion 43b of distance sensor Light receiving portion of distance measuring sensor 44 Blower nozzle 44a Open end of blower nozzle 44b Base end of blower nozzle 45 Flexible tube

Claims (4)

A mobile robot that moves on an outdoor road surface by a moving means,
A detection unit that detects information on obstacles that may interfere with traveling through the detection window;
A water droplet removal unit that blows air to the detection window of the detection unit to remove water droplets attached to the detection window;
A road surface state detection unit for detecting the wet state of the road surface;
A control unit that determines movement start based on a schedule stored in advance or a signal input from the outside,
When the road surface state detection unit does not determine that the road surface is wet when the control unit determines that the movement is started, the control unit controls the moving unit to start moving, and determines whether the road surface is wet. In the case of being performed, the water drop removing unit is activated, and the moving means is controlled to start moving after a predetermined time has elapsed since the activation.
The control unit determines that the detection unit is abnormal when the detection unit detects an obstacle near the detection window when the predetermined time has elapsed, and prohibits the start of movement. The mobile robot according to 1.
The road surface state detection unit detects a wet state of the road surface when moving on the road surface by the moving means,
The controller activates the water drop removing unit when the road surface is wet when the moving means is moving on the road surface, and if the road surface is not wet, the control unit The mobile robot according to claim 1, wherein the operation is stopped.
The said control part is a mobile robot in any one of Claim 1 to 3 which stops the operation | movement of the said water droplet removal part, if the movement by the said moving means stops.

Images