JP5470516B2 - Radio communication apparatus for operating mobile unit, communication control program, and mobile unit - Google Patents

Description

  The present invention relates to a radio communication device for operating a mobile unit, a communication control program, and a mobile unit, and more particularly to a radio communication device for operating a mobile robot, a communication control program, and a mobile robot.

  In general, when a mobile unit such as a robot, an automatic guided machine, or an electric cart is remotely controlled, a safe remote control is not possible unless the connection between the remote control device operated by the operator and the mobile unit is always maintained. It becomes difficult. In remote operation through a wireless link, it is required to maintain a constant connection exceeding the required slew rate with a certain communication quality, that is, a low delay and a low error rate.

  On the other hand, in order to widen the moving range of a moving body, a method of extending a communicable range by providing a plurality of access points (AP) in a network is generally taken. However, in this method, when the handover is performed by leaving the communicable area of the AP that is currently communicating by moving and reconnecting to another adjacent AP, the delay and error temporarily increase, and the always-on connection is maintained. There are often situations where it is difficult to continue. In particular, when moving indoors at an intricate structure at a constant speed, usually the handover is performed based on the received signal strength. There are many examples in which the connection with the AP is disconnected.

As a method for preventing this, control information of neighboring APs, for example, information such as parameters necessary for connection and transmission timing that enables high-speed reconnection (neighboring APs) is prepared in case handover is necessary due to movement. Conventionally, a method of notifying a mobile body of (connection information to) is known. For example, Patent Document 1 discloses a method of sending control information of an adjacent AP (cell) from a currently connected AP (base station) to a mobile phone in a mobile phone system.
Japanese translation of PCT publication No. 2002-533032

  However, an autonomous distributed system such as a wireless LAN generally does not have a function for collecting, managing and notifying control information of neighboring APs centrally. Moreover, even in the system of Patent Document 1, in an indoor environment partitioned by a wall that does not allow radio waves to pass through or in a place where buildings are forested outdoors, the cells overlap in a complicated manner. Adjacent cells cannot be easily identified. Also, there may not be sufficient overlap between cells.

  Therefore, a main object of the present invention is to provide a novel wireless communication apparatus for operating a mobile unit, a communication control program, and a mobile unit.

  Another object of the present invention is to provide a wireless communication apparatus for operating a mobile unit, a communication control program, and a mobile unit that can suppress communication interruption at the time of handover as much as possible with a simple configuration.

  The present invention employs the following configuration in order to solve the above problems. The reference numerals in parentheses, supplementary explanations, and the like indicate correspondence relationships with embodiments described later to help understanding of the present invention, and do not limit the present invention in any way.

  A first aspect of the present invention is a mobile unit operating radio communication device for a mobile unit that is remotely operated via any one of a plurality of radio base stations, and wirelessly communicates with any one of the plurality of radio base stations. A second antenna having directivity directed in the moving direction of the moving body, and a signal from a radio base station positioned along the moving direction of the moving body among the plurality of radio base stations. Detecting means for detecting the first antenna, registering means for registering information based on the signal detected by the detecting means, and when the communication quality by the first antenna falls below a threshold, the first antenna Switching means for switching communication partners is provided.

  In the first invention, the wireless communication device for mobile object operation (10A) is a wireless communication device for the mobile object (10) remotely operated via any one of the plurality of wireless base stations (202 to 208). And a first antenna (118) for performing wireless communication with any one of a plurality of wireless base stations, and a second antenna (120) having directivity facing the moving direction of the moving body. In such a mobile unit operating wireless communication device (10A), for example, the communication control program (142) causes the processor (80) to function as the detection unit (S7), the registration unit (S9, S15), and the switching unit (S33). Can do.

  The detection means detects a signal from a radio base station located along the moving direction of the mobile body among the plurality of radio base stations by the second antenna, and the registration means registers information based on the signal detected by the detection means To do. The switching unit switches the communication partner of the first antenna based on the registration information of the registration unit when the communication quality by the first antenna falls below the threshold (S1: NO).

  According to the first invention, the signal from the radio base station located along the moving direction is detected by the second antenna having directivity, information related thereto is registered, and the communication quality of the first antenna has a threshold value. When the number is lower, the communication partner of the first antenna is switched based on the registration information. Therefore, communication interruption at the time of handover can be suppressed as much as possible with a simple configuration.

  A second invention is dependent on the first invention, and the first antenna has variable directivity. An example of a variable directivity antenna is an array antenna.

  According to the second invention, since the first antenna has variable directivity, radio communication with a radio base station located in an arbitrary direction can be performed, and an increase in received signal strength due to the antenna gain and other signals. Due to the interference suppression effect, the communicable area is expanded.

  A third invention is dependent on the first invention, and the second antenna captures a weak signal transmitted from a radio base station located along the moving direction of the moving body and reflected in the environment. Note that it is difficult to perform normal communication such as obtaining registration information of neighboring cells with the weak signal intensity captured by the second antenna, but the modulation method, preamble, spectrum pattern, and signal duration that the signal has The presence of the cell can be confirmed by any one of the characteristics such as the signal intensity change pattern or a combination thereof.

  According to the third invention, since the weak signal reflected in the environment is captured by the second antenna, it is possible to detect a radio base station that exists further along the moving direction. Even if there is not enough overlap in the possible area, communication interruption can be minimized.

  A fourth invention is dependent on the first invention, and the registering means registers identification information for identifying a transmission source of the signal detected by the detecting means.

  According to the fourth invention, connection to an adjacent radio base station is possible based on the registered identification information.

  The fifth invention is dependent on the fourth invention and further comprises extraction means (S11) for extracting connection information from the signal detected by the detection means to the transmission source of the signal, and the registration means is provided by the extraction means. Further register the extracted connection information.

  The connection information includes, for example, a channel (frequency) and transmission speed used by the radio base station, and a transmission timing that enables high-speed connection.

  According to the fifth aspect, by further referring to the connection information, high-speed connection to an adjacent radio base station is possible.

  The sixth invention is dependent on the first invention, and the registration means attaches the detection time of the signal when registering information based on the signal detected by the detection means (S9), and the registration information by the registration means Among these, deletion means (S17, S19) for deleting registration information whose elapsed time from the attached detection time has passed a predetermined time limit is further provided.

  In the sixth aspect of the invention, since the registration information based on the signal that has passed the predetermined time limit from the detection is deleted, an increase in the amount of registration information can be suppressed and inappropriate overhand based on the old registration information can be avoided. .

  The seventh invention is dependent on the first invention, and when the communication quality by the first antenna is below the threshold value and the registration information by the registration means does not exist, the movement of the moving body is forcibly stopped. On the other hand, when registration information by the registration unit exists, a stop control unit is further provided that permits the movement of the moving object.

  In the seventh invention, the movement of the moving body when the communication quality by the first antenna is below the threshold (S1: NO) is determined when the registration information by the registration means does not exist by the stop control means (S41). (S29: NO) is forcibly stopped, while if registration information by the registration means exists (S29: YES), it is accepted.

  According to the seventh invention, when the mobile body departs from the communicable area, whether to move the mobile body or to forcibly stop it is determined depending on whether or not there is a radio base station at the destination. If the communication is interrupted, the movement is forcibly stopped, and if the communication is temporarily interrupted, the movement is accepted, and the moving range of the moving body can be expanded safely.

  An eighth invention is according to the seventh invention, further comprising measurement means for measuring a duration of a state in which the communication quality by the first antenna is below a threshold, and the forced stop means further includes a measurement result of the measurement means When the time reaches a predetermined time, the movement of the moving body is forcibly stopped.

  In the eighth invention, the duration of the state where the communication quality by the first antenna is below the threshold is measured by the measuring means (S3, S27). When the measurement result reaches a predetermined time (S25: NO), the moving body is forcibly stopped by the stop control means.

  According to the eighth invention, even if the movement is permitted in a state where the communication quality by the first antenna is below the threshold, it is limited within a predetermined time, so that it is possible to further ensure safety. .

  In addition, the moving distance of the moving body in a state where the communication quality by the first antenna is below the threshold is measured (the moving distance may be calculated from the duration and moving speed of the state), and the measurement (calculation) result The movement of the moving body may be forcibly stopped when the distance reaches a predetermined distance.

  A ninth invention is a mobile wireless communication device (10A) for operating a mobile body (10) via any one of a plurality of wireless base stations (202 to 208), wherein A mobile radio communication apparatus (10A) including a first antenna (118) for performing radio communication with any one of the base stations, and a second antenna (120) having directivity facing the moving direction of the mobile body ) Of the processor (80) is detected by the detection means (S7), which detects the signal from the radio base station located along the moving direction of the mobile body among the plurality of radio base stations by the second antenna. The registration means for registering information based on the signal (S9, S15), and the communication phase of the first antenna based on the registration information of the registration means when the communication quality by the first antenna falls below the threshold (S1: NO) To function as means (S33) switch switches the a communication control program (142).

  A tenth invention is a mobile unit (10) operated via any one of a plurality of radio base stations (202 to 208), and performs radio communication with any one of the plurality of radio base stations. A first antenna (118), a second antenna (120) having directivity facing the moving direction of the moving body, and a wireless base station located along the moving direction of the moving body among a plurality of wireless base stations Detecting means (S7) for detecting the second signal by the second antenna, registration means (S9, S15) for registering information based on the signal detected by the detecting means, and when the communication quality by the first antenna falls below a threshold value (S1: NO), switching means (S33) for switching the communication partner of the first antenna based on the registration information of the registration means.

  In each of the ninth and tenth inventions, similarly to the first invention, communication interruption during handover can be suppressed as much as possible with a simple configuration.

  The eleventh invention is dependent on the tenth invention, in a state where the communication means by the moving means (86, S61 to S77) for moving the mobile body itself and the communication quality by the first antenna are below the threshold (S1: NO) When the registration information by the registration means does not exist (S29: NO), the movement means is controlled to forcibly stop the movement of the moving body itself, while when the registration information by the registration means exists (S29: YES) Further provided is stop control means (S41) for allowing the movement of the moving body.

  In the eleventh invention, similarly to the seventh invention, the moving range of the moving body can be expanded safely.

  According to the present invention, a wireless communication apparatus for operating a mobile body, a communication control program, and a mobile body that can suppress communication interruption at the time of handover as much as possible with a simple configuration are realized.

  The above object, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

It is an illustration figure which shows the structure of the mobile robot remote control system which is one Example of this invention. It is an illustration figure which shows the external view of a mobile robot. It is a block diagram which shows the electric constitution of a mobile robot. It is a block diagram which shows an example of the electrical constitution of a remote control device. It is a block diagram which shows an example of the electrical structure of a server. It is an illustration figure which shows the example of the environment where a mobile robot remote control system is applied, and the communicable area | region by the antenna 1 there. FIG. 7 is an illustrative view showing a relationship between a signal detection range by the antenna 2 and a communicable region by the antenna 1 when the mobile robot is at the position P2 in the environment of FIG. It is an illustration figure which shows the relationship between the signal detection range by the antenna 2, and the arrival area | region of the reflected signal transmitted from AP208 and reflected in the environment, (A) is the relationship between both when the mobile robot is in the position P3, ( B) shows the relationship between the two when the mobile robot is at position P4. It is an illustration figure which shows the memory map of a mobile robot. It is an illustration figure which shows the detail of the main items in a memory map, (A) shows a system parameter, (B) shows a switching candidate list | wrist, (C) shows communication status information. It is a flowchart which shows a part of CPU operation | movement of a robot. It is a flowchart which shows another part of CPU operation | movement of a robot. It is a flowchart which shows a part of other CPU operation | movement of a robot. It is a flowchart which shows a part of CPU operation | movement of a remote control device. It is a flowchart which shows a part of CPU operation | movement of a server.

  Referring to FIG. 1, a mobile robot remote control system (hereinafter referred to as “remote control system”) 100 according to an embodiment of the present invention is different from mobile robot 10 disposed in, for example, a museum, an attraction facility, or an event venue. System for remote control via a network 200 such as a LAN or the Internet from a place such as a laboratory or a monitoring center.

  First, an outline will be described. The remote operation system 100 includes a mobile robot 10, a remote operation device 12, and a server 14. A plurality of, for example, four access points (hereinafter “AP”) 202 to 208 are provided in the network 200, and the mobile robot 10 is connected to the network 200 via any one of the APs 202 to 208. In other words, the mobile robot 10 can maintain the connection with the network 200 by sequentially switching the connection destination as AP202 → AP204 →... With movement (so-called “handover”).

  On the other hand, the remote control device 12 and the server 14 are connected to the network 200 via dedicated APs (not shown). The connection between the mobile robot 10 and each of the APs 202 to 208 is, for example, a wireless connection such as IEEE 802.11, but the connection between each of the remote control device 12 and the server 14 and its dedicated AP is a wireless connection. However, a wired connection such as a LAN cable may be used.

  The mobile robot 10 is, for example, an autonomous robot, and can move or act autonomously based not only on remote operation but also on sensor information from various sensors included in the mobile robot 10. Sensor information from the mobile robot 10 is also transmitted to the remote control device 12 via the network 200.

  A plurality of, for example, two laser range finders (hereinafter “LRF”) 142 and 144 are connected to the server 14. Each LRF 142, 144 is installed in a place (environment) where the mobile robot 10 can move, measures the distance from itself to the mobile robot 10, and outputs distance data. The server 14 calculates the position and moving direction of the mobile robot 10 in the environment based on the distance data from the LRFs 142 and 144. The position & direction information indicating the calculation result is transmitted to the mobile robot 10 and the remote control device 12 via the network 200.

  Note that LRF generally measures the distance to a target based on the time it takes to irradiate a laser and reflect it back at the target. For example, the LRFs 142 and 144 simply reflect a laser beam emitted from a transmitter (not shown) by a rotating mirror (not shown) and scan the front in a fan shape at a certain angle (for example, 0.5 degrees). In addition to measuring the distance to the target, it is also possible to generate two-dimensional distance information about the surface of the target (information describing the shape of the surface with two variables of angle and distance). The distance data from the LRFs 142 and 144 includes such two-dimensional distance information, and the server 14 can identify whether the target is the mobile robot 10 or another object or human body. it can.

  Note that the sensor (distance sensor) that is installed in the environment and measures the distance to the mobile robot 10 is not limited to the LRF, and may be an infrared distance sensor, for example.

  The remote operation device 12 includes a display (30: see FIG. 4) for displaying sensor information obtained from the mobile robot 10 and position & direction information obtained from the server 14, and an operation panel (28: see FIG. 4) operated by the operator. ). The operator monitors the movement (movement and / or behavior) of the mobile robot 10 through the sensor information and the position & direction information displayed on the display (30), and controls the movement as necessary. To operate. The operation information based on the operation of the operation panel (28) is transmitted to the mobile robot 10 via the network 200.

  In the mobile robot 10, motion control information is generated based on its own sensor information, position & direction information from the server 14, and operation information from the remote control device 12, and various motors (92 to 98) based on this motion control information. 110, 36a and 36b: see FIG. 3). In this way, the movement of the mobile robot 10 by autonomous / remote operation is realized.

  Note that the mobile robot 10 is also an interaction-oriented robot, and has a function of executing a communication action such as a body motion such as gesture gesture or voice conversation with a communication target such as a human.

  Next, each element will be described in detail. FIG. 2 is a front view showing the appearance of the mobile robot 10 of this embodiment. Referring to FIG. 2, mobile robot 10 includes a carriage 30, and a lower surface of carriage 30 is provided with right wheel 32 a and left wheel 32 b (referred to as “wheel 32” unless otherwise specified) and one slave wheel 34. It is done. The right wheel 32a and the left wheel 32b are independently driven by the right wheel motor 36a and the left wheel motor 36b (see FIG. 4), respectively, and can move the carriage 30 and the entire mobile robot 10 in an arbitrary direction of front, rear, left and right. The slave wheel 34 is an auxiliary wheel that assists the wheel 32.

  A cylindrical sensor attachment panel 38 is provided on the carriage 30, and a large number of infrared distance sensors 40 are attached to the sensor attachment panel 38. These infrared distance sensors 40 measure the distance between the sensor mounting panel 38, that is, the mobile robot 10 itself, and the surrounding objects (such as humans and obstacles).

  In this embodiment, an infrared distance sensor is used as the distance sensor. However, instead of the infrared distance sensor, a small LRF, an ultrasonic distance sensor, a millimeter wave radar, or the like can be used. May be used in appropriate combination.

  A body 42 is provided on the sensor mounting panel 38 so as to stand upright. In addition, the above-described infrared distance sensor 40 is further provided in the upper front upper portion of the body 42 (a position corresponding to a human chest), thereby measuring the distance to a front object such as a human. Further, the body 42 is provided with a support column 44 extending from substantially the center of the upper end portion on the side surface. On the support column 44, an omnidirectional antenna 118 and a directional antenna 120 ("antenna 1" and "antenna 2", respectively) are provided. As well as an omnidirectional camera 46.

  The omnidirectional antenna 118 is an antenna for performing wireless communication with each of the APs 202 to 208, receives a radio signal from an arbitrary direction, and transmits a radio signal in an arbitrary direction. The directional antenna 120 has directivity (for example, 20 to 30 degrees width) directed in the moving direction of the mobile robot 10, and a radio signal (for example, 5 GHz to 2.4 GHz) from the direction, particularly from each AP 202 to 208. Detect or receive weak signals transmitted and reflected in the environment.

  In this embodiment, the directional antenna 120 is fixed to the support post 44, and the support post 44 is fixed to the body 42, and the moving direction of the mobile robot 10 is the front direction of the body 42, and hence the direction. Always coincides with the directivity direction of the directional antenna 120. However, the mobile robot 10 may be movable in a direction (for example, the back direction) different from the front direction of the body 42. In this case, a motor 120a for the antenna 2 is added, or the directional antenna 120 is It is necessary to perform control to make the directivity direction coincide with the movement direction by using a variable directivity antenna (such as an array antenna) capable of electrically changing the directivity.

  The omnidirectional camera 46 photographs the surroundings of the mobile robot 10 and is distinguished from an eye camera 70 described later. As the omnidirectional camera 46, for example, a camera using a solid-state imaging device such as a CCD or a CMOS can be employed. In addition, the installation positions of the infrared distance sensor 40, the directional antenna 120, the omnidirectional antenna 118, and the omnidirectional camera 46 are not limited to the portions, and may be changed as appropriate.

  An upper arm 50R and an upper arm 50L are provided at upper end portions on both sides of the torso 42 (position corresponding to a human shoulder) by a shoulder joint 48R and a shoulder joint 48L, respectively. Although illustration is omitted, each of the shoulder joint 48R and the shoulder joint 48L has three orthogonal degrees of freedom. That is, the shoulder joint 48R can control the angle of the upper arm 50R around each of three orthogonal axes. A certain axis (yaw axis) of the shoulder joint 48R is an axis parallel to the longitudinal direction (or axis) of the upper arm 50R, and the other two axes (pitch axis and roll axis) are orthogonal to the axes from different directions. It is an axis to do. Similarly, the shoulder joint 48L can control the angle of the upper arm 50L around each of three orthogonal axes. A certain axis (yaw axis) of the shoulder joint 48L is an axis parallel to the longitudinal direction (or axis) of the upper arm 50L, and the other two axes (pitch axis and roll axis) are orthogonal to the axes from different directions. It is an axis to do.

  In addition, an elbow joint 52R and an elbow joint 52L are provided at the respective distal ends of the upper arm 50R and the upper arm 50L. Although illustration is omitted, each of the elbow joint 52R and the elbow joint 52L has one degree of freedom, and the angle of the forearm 54R and the forearm 54L can be controlled around the axis (pitch axis).

  A sphere 56R and a sphere 56L corresponding to a human hand are fixedly provided at the tips of the forearm 54R and the forearm 54L, respectively. However, when a finger or palm function is required, a “hand” in the shape of a human hand can be used. Although not shown, the front surface of the carriage 30, the portion corresponding to the shoulder including the shoulder joint 48R and the shoulder joint 48L, the upper arm 50R, the upper arm 50L, the forearm 54R, the forearm 54L, the sphere 56R, and the sphere 56L, A contact sensor 58 (shown generically in FIG. 3) is provided. A contact sensor 58 on the front surface of the carriage 30 detects contact of a person or another obstacle with the carriage 30. Therefore, the mobile robot 10 can detect the contact with the obstacle during its movement and immediately stop the driving of the wheel 32 to suddenly stop the movement of the mobile robot 10. Further, the other contact sensors 58 detect whether or not the respective parts are touched. In addition, the installation position of the contact sensor 58 is not limited to the said site | part, and may be provided in an appropriate position (position corresponding to a person's chest, abdomen, side, back, and waist).

  A neck joint 60 is provided at the upper center of the body 42 (a position corresponding to a person's neck), and a head 62 is further provided thereon. Although illustration is omitted, the neck joint 60 has a degree of freedom of three axes, and the angle can be controlled around each of the three axes. A certain axis (yaw axis) is an axis that goes directly above (vertically upward) the mobile robot 10, and the other two axes (pitch axis and roll axis) are axes orthogonal to each other in different directions.

  The head 62 is provided with a speaker 64 at a position corresponding to a human mouth. The speaker 64 is used for the mobile robot 10 to communicate with a person around it by voice or sound. A microphone 66R and a microphone 66L are provided at a position corresponding to a human ear. Hereinafter, the right microphone 66R and the left microphone 66L may be collectively referred to as a microphone 66. The microphone 66 captures ambient sounds, in particular, the voices of humans who are subjects of communication. Furthermore, an eyeball part 68R and an eyeball part 68L are provided at positions corresponding to human eyes. The eyeball portion 68R and the eyeball portion 68L include an eye camera 70R and an eye camera 70L, respectively. Hereinafter, the right eyeball portion 68R and the left eyeball portion 68L may be collectively referred to as the eyeball portion 68. Further, the right eye camera 70R and the left eye camera 70L may be collectively referred to as an eye camera 70.

  The eye camera 70 captures a human face approaching the mobile robot 10, other parts or objects, and captures a corresponding video signal. The eye camera 70 can be the same camera as the omnidirectional camera 46 described above. For example, the eye camera 70 is fixed in the eyeball unit 68, and the eyeball unit 68 is attached to a predetermined position in the head 62 via an eyeball support unit (not shown). Although illustration is omitted, the eyeball support portion has two degrees of freedom, and the angle can be controlled around each of these axes. For example, one of the two axes is an axis (yaw axis) in a direction toward the top of the head 62, and the other is orthogonal to the one axis and goes straight in a direction in which the front side (face) of the head 62 faces. It is an axis (pitch axis) in the direction to be performed. By rotating the eyeball support portion around each of these two axes, the tip (front) side of the eyeball portion 68 or the eye camera 70 is displaced, and the camera axis, that is, the line-of-sight direction is moved. Note that the installation positions of the speaker 64, the microphone 66, and the eye camera 70 described above are not limited to those portions, and may be provided at appropriate positions.

  As described above, the mobile robot 10 according to this embodiment includes independent two-axis driving of the wheels 32, three degrees of freedom of the shoulder joint 48 (6 degrees of freedom on the left and right), and one degree of freedom of the elbow joint 52 (two degrees of freedom on the left and right). The neck joint 60 has a total of 17 degrees of freedom: 3 degrees of freedom of the neck joint and 2 degrees of freedom of the eyeball support (4 degrees of freedom on the left and right).

  FIG. 3 is a block diagram showing an electrical configuration of the mobile robot 10. Referring to FIG. 3, mobile robot 10 includes a CPU 80. The CPU 80 is also called a microcomputer or a processor, and is connected to the memory 84, the motor control board 86, the sensor input / output board 88 and the audio input / output board 90 via the bus 82. The CPU 80 includes an RTC (Real Time Clock) 80a, and adds time data based on the RTC to signals or data (sensor information) from each sensor.

  Although not shown, the memory 84 includes an SSD (Solid State Drive) and ROM as a nonvolatile memory (storage area), and a RAM as a volatile memory (temporary storage area). In the SSD, ROM, that is, the storage area (140: see FIG. 9), various control programs and system parameters for controlling the movement of the mobile robot 10 itself and communication with the remote control device 12 and the server 14 (described later). ) Is stored in advance. The RAM, that is, the temporary storage area (150: see FIG. 9) can be used as a work memory or a buffer memory to temporarily store transmission / reception data, and to update various information and switching candidate lists (described later) referred to by the control program. Or remember.

  The motor control board 86 is constituted by, for example, a DSP, and controls driving of each axis motor such as each arm, neck joint, and eyeball unit. That is, the motor control board 86 receives the control data from the CPU 80, and controls two motors for controlling the angles of the two axes of the right eyeball portion 68R (in FIG. 3, they are collectively referred to as “right eyeball motor 92”). Control the rotation angle. Similarly, the motor control board 86 receives two control data from the CPU 80 and controls two angles of the two axes of the left eyeball portion 68L (in FIG. 3, collectively referred to as “left eyeball motor 94”). ) To control the rotation angle.

  The motor control board 86 receives control data from the CPU 80, and includes a total of four motors including three motors for controlling the angles of the three orthogonal axes of the shoulder joint 48R and one motor for controlling the angle of the elbow joint 52R. The rotation angle of two motors (collectively indicated as “right arm motor 96” in FIG. 3) is controlled. Similarly, the motor control board 86 receives control data from the CPU 80, and includes a total of three motors for controlling the angles of the three orthogonal axes of the shoulder joint 48L and one motor for controlling the angle of the elbow joint 52L. The rotation angles of the four motors (collectively indicated as “left arm motor 98” in FIG. 3) are controlled.

  Further, the motor control board 86 receives the control data from the CPU 80, and shows three motors (collectively “head motor 110” in FIG. 3) that control the angles of the three orthogonal axes of the neck joint 60. ) To control the rotation angle. The motor control board 86 receives control data from the CPU 80 and individually controls the rotation angles of the right wheel motor 36a for driving the right wheel 32a and the left wheel motor 36b for driving the left wheel 32b. In this embodiment, a motor other than the wheel motor 36 uses a stepping motor (that is, a pulse motor) in order to simplify the control. However, a DC motor may be used similarly to the wheel motor 36. The actuator that drives the body part of the mobile robot 10 is not limited to a motor that uses an electric current as a power source, and may be changed as appropriate. For example, in another embodiment, an air actuator or the like may be applied.

  Similar to the motor control board 86, the sensor input / output board 88 is configured by a DSP, and takes in signals (sensor information) from each sensor and supplies them to the CPU 80. That is, data relating to the reflection time from each of the infrared distance sensors 40 is input to the CPU 80 through the sensor input / output board 88. The video signal from the omnidirectional camera 46 is input to the CPU 80 after being subjected to predetermined processing by the sensor input / output board 88 as necessary. Similarly, the video signal from the eye camera 70 is also input to the CPU 80. Further, signals from the plurality of contact sensors 58 described above (collectively indicated as “contact sensors 58” in FIG. 3) are provided to the CPU 80 via the sensor input / output board 88.

  The sensor input / output board 88 is further connected to a right wheel speed sensor 112a for detecting the rotational speed (wheel speed) of the right wheel 32a and a left wheel speed sensor 112b for detecting the rotational speed of the left wheel 32b. Then, from each of the right wheel speed sensor 112a and the left wheel speed sensor 112b, data regarding the rotation speed (wheel speed) of the right wheel 32a and the left wheel 32b in a certain time is input to the CPU 80 through the sensor input / output boat 88. Is done.

  Similarly to the other input / output boards, the voice input / output board 90 is also configured by a DSP. In FIG. 3, voice or voice according to the voice synthesis data given from FIG. In addition, voice input from the microphone 66 is given to the CPU 80 via the voice input / output board 90.

  The CPU 80 is connected to the communication LAN board 114 via the bus 82. The communication LAN board 114 is configured by a DSP, for example, and provides transmission data given from the CPU 80 to the wireless communication circuit 116. The wireless communication circuit 116 sends the transmission data from the omnidirectional antenna 118 (antenna 1) via the network 200. To the external computer (remote control device 12, server 14). Further, the communication LAN board 114 receives data with the omnidirectional antenna 118 via the wireless communication circuit 116 and gives the received data to the CPU 80. The reception data received by the omnidirectional antenna 118 includes operation information from the remote operation device 12 and / or position & direction information from the server 14.

  The wireless communication circuit 116 detects or receives a signal (for example, a beacon signal) transmitted from an access point (AP) 202 to 208 to the network 200 or a weak signal reflected from the environment by the directional antenna 120. .

  FIG. 4 is a block diagram showing an electrical configuration of the remote control device 12. Referring to FIG. 4, remote control device 12 includes CPU 20, memory 22, communication LAN board 24, communication circuit 26, operation panel 28, and display 30. The communication circuit 26 is connected to the network 200 wirelessly or via a dedicated AP (not shown).

  The operation panel 28 includes various operation buttons, a touch panel, and the like. The operation panel 28 receives an operation performed by the operator to control the movement of the mobile robot 10 and outputs the operation data. The CPU 20 includes the RTC 20a, adds time data based on the RTC 20a to the operation data input from the operation panel 28, and writes this (operation data with time) in the memory 22 as transmission data (operation information). The CPU 20 also reads the transmission data stored in the memory 42 according to the time data, and gives it to the communication LAN board 24. The communication LAN board 24 is configured by a DSP, for example, and transmits transmission data given from the CPU 20 to the mobile robot 10 from the communication circuit 46 through the network 200.

  The communication LAN board 24 also receives data (sensor information and position & direction information) sent from the mobile robot 10 and the server 14 via the network 200 by the communication circuit 26 and gives the received data to the CPU 20. The CPU 20 writes the given received data in the memory 22 and visually shows the sensor information from the mobile robot 10 and the position & direction information from the server 14 based on the received data thus stored in the memory 22. A screen (not shown) is displayed on the display 30. The operation by the operator as described above is performed with reference to the control screen displayed on the display 30 in this way.

  In the memory 22, a control program (see FIG. 14: described later) for the remote operation device 12 to perform the above-described operation is stored in advance.

  FIG. 5 is a block diagram showing an electrical configuration of the server 14. Referring to FIG. 5, the server 14 includes a CPU 40, a memory 42, a communication LAN board 44, a communication circuit 46 and a sensor input / output board 48. The communication circuit 46 is connected to the network 200 wirelessly or via a dedicated AP (not shown). The sensor input / output board 48 is connected to the LRFs 142 and 144 shown in FIG. The CPU 40 includes an RTC 40a, adds time data obtained from the RTC 40a to distance data input from the LRFs 142 and 144 through the sensor input / output board 48, and stores this (distance data with time) in the memory 42. Write. The CPU 40 also calculates the position and moving direction of the mobile robot 10 in the environment based on the time-distance data stored in the memory 42 in this way, and writes the calculation result (position & direction information) in the memory 42 again as transmission data. . The communication LAN board 44 is configured by a DSP, for example, and transmits the transmission data thus stored in the memory 42 from the communication circuit 46 to the mobile robot 10 through the network 200.

  The memory 42 stores in advance a control program (see FIG. 15: described later) for the server 14 to perform the above operation.

  FIG. 6 is an illustrative view showing an example of an environment to which the remote operation system 100 is applied and a communicable area by the omnidirectional antenna 118 (antenna 1) in the environment. This environment is, for example, one floor of a museum, and is divided into three rooms 1 to 3 and a passage by a wall that does not transmit radio waves. AP 202 is arranged on the entrance ent side of the passage, and APs 204 to 208 are arranged in the rooms 1 to 3, respectively. The LRFs 142 and 144 are installed at appropriate positions in the passage. The communicable area in this environment (area where signals from at least one of the APs 202 to 208 reach) is an area indicated by shading and covers all of the rooms 1 to 3 and a part of the passage.

  In the passage, the signal arrival area E1 from the AP 202 extends from the entrance Ent1 to the vicinity of the wall W1 between the rooms 1 and 2, and the signal arrival areas E2 to E4 from the APs 204 to 208 are in the rooms 1 to 3. From the inside of the aisle. The front end portion of the signal arrival area E2 from the AP 204 overlaps the front end portion of the signal arrival area E1 from the AP 202, and the front end portion of the signal arrival area E3 from the AP 206 is in the signal arrival area E2 from the AP 204. It is in contact with the tip (that is, there is almost no overlap). And the front-end | tip part of signal arrival area | region E4 from AP208 is far away from the front-end | tip part of signal arrival area | region E3 from AP206.

  Now, it is assumed that the mobile robot 10 moves along the line L from the entrance Ent to the back in the path of P1 → P2 → P3 → P4 →. In this case, as the mobile robot 10 moves, the communication partner of the antenna 1 is sequentially switched in the order of AP202 → AP204 → AP206 → AP208. Specifically, the communication partner of the antenna 1 is the AP 202 between the positions P1 and P2, and is switched to the AP 204 immediately after the position P1. And it switches to AP206 further after a communication interruption in the middle of position P2-P3. This instantaneous communication interruption occurs because there is almost no overlap between the signal arrival area E2 from the AP 204 and the signal arrival area E3 from the AP 206, and causes a movement stop. However, the mobile robot 10 can avoid this type of communication interruption by using the antenna 2, and even if a communication interruption occurs, the mobile robot 10 passes through the boundary without being paused.

  A specific method of using the antenna 2 will be described with reference to FIG. FIG. 7 shows the relationship between the signal detection range by the antenna 2 and the communicable area by the antenna 1 when the mobile robot 10 is at the position P2. As shown in FIG. 7, the signal detection range by the antenna 2 extends forward from the position P2 beyond the position P3, and overlaps the tip portion of the signal arrival area E3 from the AP 206. Therefore, the antenna 2 can receive a signal from the AP 206 before the position P2 (or can detect a weak signal generated by the reflection of the signal in the environment). The mobile robot 10 extracts the connection information to the AP 206 (see FIG. 10B: described later) from the signal received by the antenna 2 in this manner, and recognizes the next AP 206 in advance and acquires the connection information to it. Therefore, high-speed handover (switching of communication partner) from the AP 204 to the AP 206 can be performed. Even if the connection information cannot be acquired, it can be seen that the next AP 206 exists immediately before, so that the moving state can be maintained.

  Returning to FIG. 6, after that, when the position P3 is passed, since the signal arrival area E4 from the next AP 208 is far away, communication is interrupted until the signal arrival area E4 is reached. However, even if such a communication interruption period occurs, the mobile robot 10 continues to maintain the moving state using the antenna 2 and enters the signal arrival area E4. Then, when the vehicle passes the position P4, that is, when it leaves the signal arrival area E4, the movement is stopped.

  A specific method of using the antenna 2 here will be described with reference to FIG. FIG. 8 shows the relationship between the signal detection range by the antenna 2 and the arrival area of the reflected signal transmitted from the AP 208 and reflected by the environment. FIG. 8A shows the relationship between the two when the mobile robot 10 is at the position P3, and FIG. 8B shows the relationship between the two when the mobile robot 10 is at the position P4.

  First, referring to FIG. 8A, the arrival area E4r of the reflected signal transmitted from the AP 208 and reflected by the environment (hereinafter referred to as “arrival area E4r”) enters the path in the signal arrival area E4 from the AP 208. And the signal detection range of the antenna 2 at the time of the position P3 is the same as that of the rear end portion of the arrival area E4r. overlapping. Therefore, the antenna 2 can detect a weak signal generated by the signal from the AP 208 being reflected in the environment before the position P3. Since the mobile robot 10 knows that the next AP 208 exists in the moving direction based on the weak signal detected by the antenna 2 in this way, the moving robot 10 can maintain the moving state. At this time, how far the next AP 208 exists may be predicted from the intensity of the weak signal.

  When the communication interruption state continues for a predetermined time or more, the mobile robot 10 stops moving.

  Next, referring to FIG. 8B, at the time of the position P4, the next AP no longer exists in the moving direction of the mobile robot 10. For this reason, the signal detection range of the antenna 2 does not overlap with the signal from the next AP or the arrival area of the reflected signal. When the mobile robot 10 exits the signal arrival area E4 from the AP 208, no new AP is detected by the antenna 2, so the mobile robot 10 determines that there is no AP in the moving direction and stops moving.

  When performing the operation as described above, the CPU 80 of the mobile robot 10 performs communication control processing according to the flow shown in FIGS. 11 and 12 based on the control program and information stored in the memory 84, and FIG. The motion control process according to the flow is executed in parallel. The remote control device 12 and the server 14 execute control processes according to the flows shown in FIGS. 14 and 15, respectively.

  FIG. 9 shows a memory map of the mobile robot 10, and FIG. 10 shows details of main items in the memory map. Referring to FIG. 9, memory 84 includes a storage area 140 and a temporary storage area 150. In storage area 140, communication control program 142, motion control program 144, system parameter 146, and the like are stored. In the temporary storage area 150, a switching candidate list 152, communication status information 154, sensor information 156, position & direction information 158, operation information 160, motion control information 162, and the like are stored.

  The communication control program 142 uses the omnidirectional antenna 118 (antenna 1) and the directional antenna 120 (antenna 2) to perform wireless communication with the remote control device 12 and the server 14 while sequentially switching the APs 202 to 208. It is a control program for performing, and corresponds to the flow of FIG. 11 and FIG. The movement control program 144 is a control program for the mobile robot 10 to control its own movement based on its own sensor information, operation information from the remote operation device 12, and position & direction information from the server 14. This corresponds to the flow of FIG.

  The system parameter 146 is a parameter that is set so as to be changeable by a prior setting operation with respect to the remote operation system 100. Specifically, as shown in FIG. It includes two parameters called “movement allowance time”. The values of these parameters are described as 60 seconds and 10 seconds, respectively.

  The switching candidate list 152 is a list for registering APs (202, 204,...) Detected by the antenna 2 as switching candidate APs (hereinafter, “candidate APs”). Specifically, FIG. As shown in FIG. 4, the ID (identification information), detection time, signal strength, connection information, and the like of the candidate AP are registered. Here, the connection information includes information necessary for (especially quick) connection to the AP, such as a channel (frequency), transmission speed, and transmission timing used by the AP.

  The communication status information 154 is information indicating the communication status of the mobile robot 10 itself. Specifically, as shown in FIG. 10C, “non-communication state duration (T)” and the like are described. . If T = 0, it can be seen that the communication quality of the antenna 1 is equal to or higher than the threshold (communication possible state). If T> 0, it can be seen that the communication quality by the antenna 1 is less than the threshold (communication impossible state), and further, the duration of the communication impossible state is also known by the value of the variable T. When the direction of the antenna 2 is variable, a value indicating the direction is also described here.

  The sensor information 156 is information indicating detection results by various sensors (40, 46, 58, 70, 112a and 112b) provided in the mobile robot 10 itself, and indicates, for example, distances to objects and wall surfaces existing in the vicinity. It includes distance information, image information obtained by capturing the surroundings with various cameras, contact information with the object, wheel speed information indicating the speeds of the left and right wheels, and the like. The position & direction information 158 is information received from the server 14 and indicates the position and moving direction of the mobile robot 10 itself. The server 14 may be omitted from the remote operation system 100, and the position & direction information 158 may be calculated based on sensor information from the mobile robot 10 itself.

  The operation information 160 is information received from the remote operation device 12 and indicates the operation content (command) performed by the remote operation device 12. The motion control information 162 is information generated based on the sensor information 156, the position & direction information 158, the operation information 160, and the like, and the motion of the mobile robot 10 (operations of various motors) is based on the motion control information 162. Controlled.

  Based on the communication control program 142, the CPU 80 of the mobile robot 10 executes a communication control process according to the flow of FIGS. First, referring to FIG. 11, in step S1, it is determined whether or not the communication quality (for example, delay time, error rate, slew rate, etc .: the same applies hereinafter) by the antenna 1 is equal to or higher than a threshold value. Then, “non-communication state duration (T)” which is one item of the state information 154 is reset (T = 0). If possible, in step S5, the ID and connection information of the neighboring AP are received from the connection partner (current AP) of the antenna 1 and recorded in the switching candidate list 152 (optional). In step S7, it is determined whether the antenna 2 detects a signal from another AP.

  Whether the signal detected by the antenna 2 (hereinafter referred to as “detection signal”) is from the current AP or from another AP, the identification information included in the detection signal (assigned to each AP) ID). Therefore, if significant identification information (ID for AP) cannot be extracted from the detection signal, or if the ID for AP can be extracted and is the same as the current AP, NO is determined in step S7. Then, the process proceeds to step S17 (described later).

  If “YES” in the step S7, the process shifts to a step S9 to register the detection signal transmission source as a candidate AP. Specifically, the ID extracted from the signal, the detection time, and the signal strength are recorded in the switching candidate list 152. Next, in step S11, connection information to the candidate AP is extracted from the detection signal. In step S13, it is determined whether or not significant connection information has been extracted. If NO, the process proceeds to step S17.

  If “YES” in the step S 13, the extracted connection information is added to the switching candidate list 152. Then, the process proceeds to step S17. Therefore, as shown in FIG. 10B, a candidate AP whose connection information is known and a candidate AP whose connection information is unknown can be mixed and registered in the switching candidate list 152.

  Next, referring to FIG. 12, in step S <b> 17, it is determined whether there is a candidate AP that has passed the expiration date (for example, 60 seconds) described in the system parameter 146 with reference to the switching candidate list 152. If “NO” here, the process proceeds to a step S 21, while if “YES”, such a candidate AP is deleted from the switching candidate list 152 in a step S 19. Specifically, the detection time of each candidate AP is compared with the current time, and candidate APs whose difference exceeds, for example, 60 seconds are deleted from the switching candidate list 152. After deletion, the process proceeds to step S21.

  In step S21, paying attention to the change in the position & direction information 158 (see FIG. 9), it is determined whether or not the moving direction of the mobile robot 10 has been changed to a set value or more. If NO, the process returns to step S1. This set value is determined in advance or dynamically changed in consideration of the performance of the directional antenna and the fading amount depending on the surrounding environment, and is set to, for example, half the half-value angle of the directional antenna. . If “YES” in the step S21, the switching candidate list 152 is initialized in a step S23, and then the process returns to the step S1.

  Therefore, in a state where the communication quality equal to or higher than the threshold value is obtained with the antenna 1 (between the positions P1 and P2 in FIG. 6), the loop composed of the above-described steps S1 to S23 is repeatedly executed. Is kept up to date. If the determination result in step S1 changes from YES to NO, that is, if the communication quality is below the threshold value (immediately after P3 and P4 in FIG. 6), the process goes through the above loop and proceeds to step S25.

  Returning to FIG. 11, in step S <b> 25, it is determined whether or not the non-communication state duration (variable T) is equal to or shorter than the movement allowable time (for example, 5 seconds) described in the system parameter 146. > 5 seconds), the process proceeds to step S39 (described later). If YES in step S25 (T ≦ 5 seconds), after the variable T is counted up in step S27, it is determined whether or not there is a candidate AP in the switching candidate list 152 in step S29. If NO in step S29, the process proceeds to step S39. If YES, it is further determined in step S31 whether or not all candidate APs present in the switching candidate list 152 have been tried.

  If “YES” in the step S31, the process proceeds to a step S39, while if “NO”, the connection partner of the antenna 1 is switched to an untried candidate AP in a step S33. In step S35, it is determined whether or not the communication quality by the antenna 1 after switching has become equal to or higher than the threshold value. If NO in this case, the process returns to step S25 and the same processing as described above is repeated. The threshold value in step S35 is the same value as the threshold value in step S1 or a relatively large value.

  If “YES” in the step S35, the process shifts to a step S37 to delete the candidate AP, that is, the candidate AP that becomes a new connection partner of the antenna 1 from the switching candidate list 152. Then, it returns to step S3 and repeats the same process as the above.

  Therefore, in a state where communication quality equal to or higher than the threshold value cannot be obtained with the antenna 1 (communication interruption period immediately after the position P3 in FIG. 6), the loop consisting of the above-described steps S25 to S35 is repeatedly executed. Attempts to switch to the candidate AP registered in the switching candidate list 152 of the connection partner. If switching to any candidate AP is successful within the movement acceptance time and communication quality equal to or higher than the threshold value is obtained, the process returns to the loop of steps S1 to S23. When there is no candidate AP in the switching candidate list 152, or when communication quality equal to or higher than the threshold is not obtained when all candidate APs have been tried, or communication that exceeds the threshold even after the movement allowable time elapses If the quality is not obtained, stop control is performed through steps S39 to S47 so as to interrupt the motion control.

  Specifically, in step S39, the motion control shown in FIG. 13 is interrupted, and the left and right wheel motors 36a and 36b are forcibly stopped. Next, in step S41, a notification indicating deviation from the communicable area is transmitted to the remote operation device 12. However, this notification may not reach the remote control device 12 depending on the current communication quality (step S41 may be omitted). Next, the left and right wheel motors 36a and 36b are continuously controlled to change the traveling direction (for example, in the reverse direction) in step S43, and then the movement is resumed in step S45. At this time, a notification indicating resumption of movement may be transmitted to the remote operation device 12. Thereafter, after the switching candidate list 152 is initialized in step S23, the process returns to step S1 and the same processing as described above is repeated.

  In parallel with the communication control as described above, the CPU 80 of the mobile robot 10 executes a motion control process according to the flow of FIG. 13 based on the motion control program 144. Referring to FIG. 13, first, in step S61, initial processing such as initialization of temporary storage area 150 is executed. Next, it progresses to step S63, sensor information is acquired from various sensors (40, 46, 58, 70, 112a, and 112b), and the sensor information 156 memorize | stored in the temporary storage area 150 is updated by step S65. The updated sensor information 156 is transmitted to the remote control device 12 via the communication LAN board 114 by the wireless communication circuit 116 using the omnidirectional antenna 118 (antenna 1). Thereafter, the process proceeds to step S67.

  In step S67, it is determined whether or not position & direction information has been received from the server 14. If NO, the process proceeds to step S71. If “YES” in the step S67, the position & direction information 158 stored in the temporary storage area 150 is updated in a step S69, and then the process proceeds to the step S71. In step S71, it is determined whether or not operation information has been received from the remote control device 12. If NO, the process proceeds to step S75. If “YES” in the step S71, the operation information 156 stored in the temporary storage area 150 is updated in a step S73, and then, the process proceeds to a step S75.

  In step S75, motion control information 162 is generated based on the sensor information 156, position & direction information 158, and operation information 160, and in step S77, various motors (92 to 98, 110,. 36a and 36b) are driven. Then, it returns to step S63 and repeats the same process as the above. As a result, various movements of the mobile robot 10, such as movement and communication behavior as described above, are realized.

  The CPU 20 of the remote operation device 12 executes control processing according to the flow of FIG. 13 based on a control program (not shown) stored in the memory 22. Referring to FIG. 13, first, in step S81, a control screen (not shown) is initially displayed on display 30, and then in step S83, it is determined whether or not there is an operation input to operation panel 28. If NO, the process proceeds to step S87. If “YES” in the step S83, operation information indicating the contents of the operation input is transmitted from the communication circuit 26 to the mobile robot 10 via the communication LAN board 24 in a step S85, and then, the process proceeds to a step S87. In step S87, it is determined whether or not sensor information from the mobile robot 10 and / or position & direction information from the server 14 has been received by the communication LAN board 24. If NO, the process returns to step S83. If “YES” in the step S87, the control screen of the display 30 is updated based on the reception information in a step S89, and then the process returns to the step S83. Then, the same processing as described above is repeated.

  As a result, a control screen visually showing the sensor information from the mobile robot 10 and the position & direction information of the server 14 is displayed on the display 30, and the operator can view the control screen of the display 30 as needed. By operating the operation panel 28, the mobile robot 10 can be remotely controlled.

  The CPU 40 of the server 14 executes control processing according to the flow of FIG. 14 based on a control program (not shown) stored in the memory 42. Referring to FIG. 14, first, distance information is acquired from LRFs 142 and 144 in step S91. The acquired distance information is written in the memory 42. In step S93, the distance information acquired this time is compared with the previous distance information stored in the memory 42 to determine whether or not there is a change. If NO here, the process returns to step S91. If “YES” in the step S93, the process proceeds to a step S95, and the position and the moving direction of the mobile robot 10 are calculated based on the current distance information and the previous distance information. In step S97, the position & direction information indicating the calculation result is transmitted from the communication circuit 46 to each of the mobile robot 10 and the remote control device 12 via the communication LAN board 44. Then, it returns to step S91 and repeats the same process as the above.

  Thereby, since the mobile robot 10 can know the position and moving direction of the mobile robot 10 itself, the mobile robot 10 can move autonomously. Further, since the operator who operates the remote operation device 12 can know the position and moving direction of the mobile robot 10, the mobile robot 10 can be operated remotely. Note that the server 14 may be omitted from the remote operation system 100, and the mobile robot 10 itself may calculate the position and moving direction based on the sensor information 156. This calculation result (position & direction information 158) is transmitted to the remote operation device 12.

  As apparent from the above, in this embodiment, the mobile robot 10 is remotely operated via any one of the APs 202 to 208. Such a mobile robot 10 (or mobile robot operating radio communication device 10A: see FIG. 3) has a non-directional antenna 118 for performing radio communication with any one of the APs 202 to 208, and the moving direction of the mobile robot 10. A directional antenna 120 having directivity and a CPU 80 are provided. The CPU 80 detects a signal from the AP located along the moving direction of the mobile robot 10 among the APs 202 to 208 by the directional antenna 120 (S7), and registers information based on the detected signal in the switching candidate list 152 ( S9, S15), and when the communication quality by the omnidirectional antenna 118 falls below the threshold (S1: NO), the communication partner of the omnidirectional antenna 118 is switched based on the registration information of the switching candidate list 152 (S33). . Thus, with a simple configuration, communication interruption at the time of handover can be suppressed as much as possible.

  In addition, when the communication quality by the omnidirectional antenna 120 is below the threshold (S1: NO), the CPU 80 determines that the mobile robot 10 itself has no registration information in the switching candidate list 152 (S29: NO). While the movement is forcibly stopped, if the registration information exists (S29: YES), the movement of the mobile robot 10 is permitted (S41). Therefore, when the mobile robot 10 departs from the communicable area, it is determined whether to accept or forcibly stop the movement depending on whether there is a radio base station at the destination. If this is the case, the movement is forcibly stopped, and if the communication is temporarily interrupted, the movement is permitted, and the movement range of the mobile robot 10 can be expanded safely.

  In the above, the mobile robot 10 (mobile robot operation wireless communication device 10A) has been described. However, the present invention can be used for various mobile objects (mobile operation wireless communication device) such as an automatic guided machine and an electric cart. it can.

  In the above description, the radio wave is detected by an omnidirectional antenna and a directional antenna. However, in addition to such a combination, a combination of a radio wave and a variable directional antenna, a directional antenna, a radio wave and a variable directional antenna, Combination with a variable directional antenna is also possible. In addition, visible light or infrared light and photo detectors, photodetectors, light receivers, light sensors, image sensors (photodiodes, phototransistors, CDS, CCDs) with directivity using optical lenses and curved mirrors You may combine. Alternatively, a combination of a terahertz wave and a detector, a detector, a sensor, and an antenna in which directivity is imparted by a dielectric lens or a curved mirror is also possible.

DESCRIPTION OF SYMBOLS 10 ... Mobile robot 12 ... Remote control device 14 ... Server 20, 40, 80 ... CPU
22, 42, 84 ... Memory 24, 44, 114 ... Communication LAN board 26, 46 ... Communication circuit 116 ... Wireless communication circuit 118 ... Omnidirectional antenna (antenna 1)
120 ... Directional antenna (antenna 2)
142,144 ... LRF (laser range finder)
200 ... network 202 to 208 ... AP (access point)

Claims (11)

A mobile radio communication apparatus for operating a mobile body via any one of a plurality of radio base stations,
A first antenna for performing wireless communication with any one of the plurality of wireless base stations;
A second antenna having directivity facing the moving direction of the moving body;
Detecting means for detecting a signal from a radio base station located along a moving direction of the mobile body among the plurality of radio base stations by the second antenna;
A registration unit for registering information based on the signal detected by the detection unit; and a communication partner of the first antenna based on registration information of the registration unit when communication quality by the first antenna is below a threshold value. A wireless communication device comprising switching means for switching.   The wireless communication apparatus according to claim 1, wherein the first antenna has variable directivity.   The radio communication apparatus according to claim 1, wherein the second antenna captures a weak signal transmitted from a radio base station located along a moving direction of the mobile body and reflected by an environment.   The wireless communication apparatus according to claim 1, wherein the registration unit registers identification information for identifying a transmission source of the signal detected by the detection unit. Further comprising extraction means for extracting connection information from the signal detected by the detection means to the transmission source of the signal;
The wireless communication apparatus according to claim 4, wherein the registration unit further registers connection information extracted by the extraction unit. The registration means attaches a detection time of the signal when registering information based on the signal detected by the detection means,
The wireless communication apparatus according to claim 1, further comprising: erasure means for erasing registration information whose elapsed time from the attached detection time has passed a predetermined time limit among registration information by the registration means.   In a state where the communication quality by the first antenna is below a threshold value, if there is no registration information by the registration means, the movement of the moving body is forcibly stopped, while there is registration information by the registration means. The wireless communication apparatus according to claim 1, further comprising stop control means for accepting the movement of the moving body in some cases. Measuring means for measuring the duration of the state in which the communication quality by the first antenna is below a threshold;
8. The wireless communication apparatus according to claim 7, wherein the forcible stop means further forcibly stops the movement of the moving body when a measurement result of the measurement means reaches a predetermined time. A mobile radio communication apparatus for operating a mobile body via any one of a plurality of radio base stations, a first antenna for performing radio communication with any one of the plurality of radio base stations And a processor of a wireless communication device for a mobile body comprising a second antenna having directivity facing the moving direction of the mobile body,
Detecting means for detecting, by the second antenna, a signal from a radio base station located along a moving direction of the mobile body among the plurality of radio base stations;
A registration unit for registering information based on the signal detected by the detection unit; and a communication partner of the first antenna based on registration information of the registration unit when communication quality by the first antenna is below a threshold value. A communication control program that functions as a switching means for switching. A mobile unit operated via any one of a plurality of radio base stations,
A first antenna for performing wireless communication with any one of the plurality of wireless base stations;
A second antenna having directivity facing the moving direction of the moving body itself;
Detecting means for detecting, by the second antenna, a signal from a radio base station located along a moving direction of the mobile body among the plurality of radio base stations;
A registration unit for registering information based on the signal detected by the detection unit; and a communication partner of the first antenna based on registration information of the registration unit when communication quality by the first antenna is below a threshold value. A moving body comprising switching means for switching. The moving means for moving the moving body itself, and when the communication quality by the first antenna is below a threshold value and there is no registration information by the registering means, the moving body is controlled to control the moving body itself. The mobile body according to claim 10, further comprising stop control means for forcibly stopping the movement of the mobile body, and accepting the movement of the mobile body when registration information by the registration means exists.

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