JP2009237851A - Mobile object control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile object control system for accurately calculating the self-location or moving direction of a mobile object. <P>SOLUTION: The mobile object control system is configured of: a mobile object equipped with a plurality of tags having unique ID; a location information supply region equipped with a detection line extended to a prescribed direction, a reading means for reading the ID of the tags, and a detection part for detecting the detection line, and configured to move in a movement region including the location information supply region; and a control part for storing map information registered at relative location coordinates for a reference point in the moving region about each of a plurality of tags. The mobile object control system includes a location information specification part for specifying the location information of a tag read from the map information specified from the map information in the control part; a time measuring part for measuring a time difference between the first time when the detection line is detected by the detection part and the second time when the detection line is detected after the first time; and a calculation part for calculating the relative location and direction of the mobile object to the reference point on the basis of the specified location information and the measured time difference. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a moving body control system for controlling movement of a moving body that moves in a moving area such as a plane.

  2. Description of the Related Art In recent years, autonomous moving bodies that autonomously move by means of wheels, legged walking, or the like, are being developed in a moving area such as a building interior or an open space without requiring human operation.

  Such an autonomous mobile body autonomously creates and stores map information related to a specific area in a moving plane, autonomously creates a movement route on the map information, and moves based on the created movement route. I do. At this time, in order to estimate which position on the stored map information the current self position corresponds to, a so-called relative position from a specific reference point is calculated based on the moving speed, direction, etc. One that performs self-position estimation by the odometry method is known.

  By the way, in the self-position estimation by the odometry method, for example, when the moving body moves by rotating the wheel, the self-position cannot be estimated correctly due to the cause of the wheel slipping on the floor surface. There is a known problem. Therefore, for example, as described in Patent Document 1, tags (for example, RFID tags) in which absolute position information is stored on a moving floor surface are installed, and those tags are read during movement, so that the estimated self-position can be obtained. There is a technique to correct.

  Also, instead of self-position estimation by the odometry method as described above, the surrounding environment is observed using a plurality of optical sensors, and the environmental information stored in advance is compared with the environmental information obtained by observation. A technique for estimating the current self position and moving direction is also known (for example, Patent Document 2). Even in such a technique, an error occurs in the estimated self-position. Therefore, the estimated self-position is corrected by reading the RFID tag installed on the moving floor surface as described above.

  In addition, the position and direction of the moving object can be grasped by a base station provided separately from the moving object by combining the RFID tag or the RFID tag and the odometry method, and position information and the like can be obtained from the moving object. Transmission techniques are also known. (For example, Patent Documents 3 to 5)

JP 2001-209429 A JP 2004-250315 A Japanese Patent Laid-Open No. 2004-21978 JP 2001-183455 A JP 2006-105696 A

  However, if the estimated position information of the moving object is to be corrected as described above, the estimated self position of the moving object can be corrected by reading a tag whose absolute position is known in advance. It is impossible to know the direction of the moving object at the time. That is, in the case of a moving body that moves while estimating the moving direction of the moving body, in the conventional technology, the moving direction (absolute direction) of the moving body is determined by infrastructure equipment provided outside the moving body. It is necessary to use a method of detecting and transmitting the information to the mobile body. In the case of such a system that controls a mobile body using an external infrastructure facility, the facility has to become large as the movement range of the mobile body increases.

  The present invention has been made to solve such problems, and provides a moving body control system capable of accurately calculating the self position and the moving direction of the moving body with simple equipment. With the goal.

  A moving body control system according to the present invention includes a position information supply region including a plurality of tags having unique IDs, a detection line extending in a predetermined direction, a reading unit that reads the ID of the tag, and the detection line. A detection unit for detecting, and a moving body that moves in a moving area including the position information supply area, and map information in which relative position coordinates with respect to a reference point in the moving area are registered for each of the plurality of tags. A control unit that stores the position information specifying unit that specifies the position information of the read tag from the map information specified from the map information, and the detection unit is the detection line. A time measurement unit that measures a time difference between the first time at which the detection line is detected and the second time at which the detection line is detected after the first time, and the position information that is specified are measured. Based on the differences among, it is characterized by comprising a calculation unit for calculating the relative position and orientation of the moving body with respect to the reference point.

  By configuring the moving body control system in this way, it is possible to calculate the self position and the moving direction of the moving body only by providing a plurality of tags and detection lines in the moving area.

  In addition, it is preferable that a plurality of the detection units are provided. In this case, the time measurement unit sets the time when the first detection unit detects the detection line among the plurality of detection units to the first time. The time difference is measured as the second time when the other detection unit detects the detection line. In this way, even if there is a single detection line in the position information supply region, the time difference during which these detection units detect the detection line can be obtained. Is possible.

  Further, when a plurality of detection lines extending in the same direction are provided in the position information supply region, the time when the detection unit detects the first detection line is set as the first time, and the second detection line is detected. The time difference may be measured using the time as the second time. If it does in this way, even if the said detection part is single, it will become possible to calculate the moving direction of a moving body.

  The plurality of tags provided in the position information supply area are preferably arranged at equal intervals in the same direction as the direction in which the detection line extends. This simplifies the calculation for calculating the position and moving direction of the moving body that is obtained when the moving body passes through the position information supply area.

  In addition, it is more preferable to provide a plurality of position information supply areas in the moving area because the moving body has many opportunities to correct the moving direction during the movement. Such a position information supply region is preferably provided in an area where the mobile object has a lot of opportunities to move. For example, the mobile object is a mobile object in which a movement route such as AGV is determined to some extent. In some cases, it is possible to always correct the moving direction by providing a position information supply area on the route.

  The detection lines provided in the position information supply area may be provided in a single direction, but may be provided so as to extend in different directions for each area. In this case, when the moving body is moving in a certain direction, the angle that the moving body crosses for each area differs from the direction in which the detection line extends in each position information supply area. The direction to do can be calculated more accurately.

  The tag may be a readable / writable tag, but may be a read-only tag. The use of read-only tags provides the advantage that such a mobile control system can be configured at a lower cost. On the other hand, by using read / write tags, absolute value information can be obtained for these tags. Can be directly stored, so that the man-hour for configuring such a mobile control system can be reduced.

  The tag is not particularly limited as long as it can read data wirelessly, but an RFID (Radio Frequency Identification) tag can also be used. By using the RFID tag, the data stored in the tag can be read at high speed using the reading means. Therefore, even if the moving body moves in the moving area at a certain high speed, the position and moving direction of the moving body Can be calculated.

  Moreover, although the said control part may be provided separately with respect to the moving body, you may incorporate in the inside of a moving body. In this way, when the moving body is an autonomous moving body that moves autonomously, the moving direction can be corrected autonomously, so that it is possible to perform autonomous movement with higher positional accuracy. .

  Further, as means for estimating the self-position of the mobile body, a signal indicating the self-position of the mobile body may be transmitted from a GPS or a base station provided separately from the mobile body. Such self-position estimation means may be provided. In this way, the mobile body autonomously corrects its own position by correcting the self-position estimated by the self-position estimation means provided in the mobile body with the self-position recognized by reading the tag. Therefore, it is possible to accurately recognize the self-position of the moving body without using a large facility or the like.

  In addition, as the above-mentioned self-position estimation means, if the one that estimates the self-position by using the odometry method by acquiring the moving direction and distance of the moving body is used, self-position estimation can be easily performed. In particular, in the case of a moving body that moves by wheels, if such an odometry method is used, self-position estimation can be performed relatively easily.

  As for the self-position estimation method other than the odometry method, for example, the reflected light of the laser light emitted from the light source is received, and the position of the object reflected by the laser light is determined based on the time taken to receive the light. A laser range finder that performs object detection (sensing) based on the principle of so-called TOF (Time of Flight), or a reflection of irradiated ultrasonic waves, and irradiates ultrasonic waves based on the intensity of the received ultrasonic waves It is also possible to use an ultrasonic sensor for sensing the rough shape and position of an object existing in the region, or a combination thereof. When the moving area of the moving body is indoors, the position and moving direction of the moving body may be estimated by incorporating indoor GPS or the like. It is also possible to use a device that estimates a self-position by optically recognizing a landmark provided at a specific location in a moving area using a camera that optically recognizes the external environment. .

  In addition, the moving body is not particularly limited in the form of moving, but the moving area may be a wheel type moving body that moves by driving a wheel that is in contact with the moving area on a plane. Good. This is particularly effective in correcting the moving direction of the moving body according to the present invention when the moving speed is fast like the wheel-type moving body.

  Further, such a moving body may be a boarding type mobile body on which a human can be boarded, or may be a moving body such as an AGV that carries an object or the like. In the case of a boarding type mobile body on which a human can ride, the mobile body may be provided with an operation unit that designates a destination in the moving area by operating the boarded human. In such a case, the present invention can be applied to a moving body in which a boarding person designates a destination and autonomously changes a route with respect to the destination.

  As described above, according to the present invention, it is possible to provide a moving body control system that can accurately calculate the moving direction of a moving body without using large-scale equipment.

Embodiment 1 of the Invention
Hereinafter, a mobile control system 1 according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 to 13. In this embodiment, the moving area of the moving body is a plane, and the moving body whose movement is controlled can carry a human and moves as a destination designated by a human. .

  FIG. 1 schematically shows a moving body control system 1 according to the present invention. A moving area (area surrounded by a broken line) on a planar floor F serving as a moving area is vehicle-type. The mode that the mobile body 10 moves is shown. In FIG. 1, it is assumed that an object is not particularly placed in the moving area on the floor F, and the moving body 10 moves in the moving area toward the point designated by the operator who is on board. It shall be able to move. 2 is a diagram schematically showing the internal configuration of the moving body 10 shown in FIG. 1, and FIG. 3 is a diagram schematically showing the moving body 10 as viewed from the side.

  As shown in FIG. 2, the moving body 10 is an opposed two-wheeled moving body including a box-shaped moving body main body 10 a, a pair of opposed wheels 11 and 11, and casters 12. , 11 and the caster 12 support the movable body main body 10a horizontally. Furthermore, inside the mobile body 10a, there are drive units (motors) 13 and 13 for driving the wheels 11 and 11, respectively, a counter 14 for detecting the rotation speed of the wheels, and a control signal for driving the wheels. And a control unit 15 for transmitting the control signal to the drive units 13 and 13 and a battery (not shown) for supplying power to these components. A storage area 15a (not shown) such as a memory provided as a storage unit provided inside the control unit 15 controls the moving speed, moving direction, moving distance, etc. of the moving body 10 based on the control signal. In addition to the program, map information P (not shown) indicating various information provided in the movement area is stored.

  Further, as shown in FIG. 3, the upper surface of the moving body main body 10 a is provided with a mounting surface 100 a for boarding an operator who operates the moving body, and at the tip of a column 100 b provided forward in the moving direction. An operation panel 100c is provided as an operation unit for an operator to specify a destination. On this operation panel 100c, an outline of the moving area is displayed, and the destination of the moving body 10 can be determined by the operator specifying a specific position during the display. .

  In addition, a reader 16 as a reading means for reading a tag described later toward the floor is provided at a substantially central portion of the bottom of the mobile body 10a, and a detection line described later is detected on the front of the bottom. Sensors 17 and 18 are provided as detection units. Note that the reader 16 reads a tag over a slightly wide range in a substantially circular shape, and can read a plurality of tags to be described later, and transmits a plurality of unique IDs of the tags read to the control unit 15. . Further, as shown in FIG. 4, the sensors 17 and 18 include a light source that irradiates light to a detection line, which will be described later, and a detector that receives light reflected by the detection line. When a detection line is detected, a detection signal is transmitted toward the control unit 15.

  The moving body 10 configured in this way independently controls the driving amount of the pair of wheels 11 and 11 so that the vehicle travels straightly, moves in a curve (turns), moves backward, and rotates on the spot (the middle point of both wheels). It is possible to perform moving operations such as turning around the center.

  Further, the moving body 10 can autonomously create a movement route to the destination in the movement region designated by operating the operation panel 100c, and can move so as to follow the movement route. As a method of creating a route from the present location to the destination, the shape of the moving area included in the map information P stored in the storage area 15a described above, and an object (an obstacle such as a wall) included in the moving area are included. ) Or the like, and a calculation method is performed by performing arithmetic processing based on the position. As an example of creating such a movement route, for example, each grid unit in a grid map obtained by virtually depicting grid lines connecting lattice points arranged at substantially constant intervals m (for example, 10 cm) is used. The current position and destination are determined and a moving route is created in the grid map. In addition, when such a movement route creation method is used, the above-described interval m can be appropriately changed according to conditions such as the accuracy of recognizing the movable curvature and absolute position of the moving body 10, Moreover, you may use as a threshold value for determining whether the mobile body 10 slipped. Also, if it is known that fixed objects such as walls and obstacles exist in this moving area, the positions of these objects are registered in advance on the grid map and stored in the storage area 15a as map information. It shall be remembered.

  Next, details of the control unit 15 provided in the moving body 10 will be described. FIG. 5 is a block diagram schematically showing each configuration for calculating the position and moving direction of the moving body in the control unit 15.

  First, as described above, the control unit 15 includes the storage area 15a for storing the map information P, the position information specifying unit 15b for specifying the position information of the tag read from the reader 16 as a reading unit, and the sensor 17. , 18 measures the time difference when the detection line is detected, the position information of the moving body based on the position information specified by the position information specifying part 15b and the time difference measured by the time measuring part 15c. Further, information such as the moving speed and distance of the moving body 10 is obtained by integrating the number of rotations of the wheels 11 and 11 detected by the counter 14 and the calculating unit 15d that calculates the moving direction, and the movement is performed from these information. A self-position estimation unit 15e that estimates the self-position (odometry position) of the moving body 10 in the region and the moving direction. A detailed method for calculating the position and moving direction of the moving body by each configuration of the control unit 15 will be described later.

Next, the position information supply area provided in the movement area will be described with reference to FIG. Within the above-mentioned movement area, position information supply areas R (R ₁ , R ₂ ,...) Are provided at a plurality of locations. FIG. 6 shows an example in which only two position information supply regions R (R _n and R _{n + 1} ) are provided in order to simplify the description.

As shown in FIG. 6, the position information supply regions R _n and R _{n + 1} are arranged on the plate-like reflecting members M _n and M _{n + 1} extending in a predetermined direction so that a plurality of tags are at regular intervals. It has a configuration. The reflecting members M _n and M _{n + 1} are formed of a material whose surface is horizontal and can maintain a predetermined reflectance, reflects light from the light source provided in the sensor 17 or 18 described above, and the sensor 17 , 18 to receive the reflected light, it is detected that the moving body 10 has passed over these reflecting members. That is, in this embodiment, these reflecting members correspond to the detection line referred to in the present invention.

On the other hand, in the on the reflecting member, the tag _T n 1 arranged in two rows at regular intervals toward the extending direction of each of the reflecting _{member, T} n 2, ..., and _{T n + 1 1, T n} + 1 2 ,. .. is arranged. These tags are generally used RFID tags, each having a unique ID, and each tag stores coordinates indicating a relative position from the reference point O in the moving region, and a reference vector. Is stored in the map information P together with the direction. In this position information supply region, a direction orthogonal to the direction in which the reflecting member extends is used as a reference vector (reference vector V _n , V _{n + 1} ), and the reference vectors of these position information supply regions are apparent from FIG. Thus, the directions are set to be different from each other.

  Next, an example of a data structure for storing such tag position information in the map information P is shown in FIG. As is clear from FIG. 7, the map information P includes information such as an area (section) where each tag exists, a reference vector, and relative coordinates (here, xy coordinates) viewed from the reference point of each tag. Are stored in association with the unique ID of the tag.

Next, a method for calculating the self-position and the moving direction of the moving body 10 configured as described above will be described with reference to FIGS. FIGS. 8 to 10, the moving body 10 is a diagram showing the moment that passes through the position information supplied on region R _n in the foregoing, Figure 8 how the passing mobile 10 over the reflective member, Figure 9 is reflected FIG. 10 shows how the moving body moves in a direction equal to the direction orthogonal to the direction in which the member extends (ie, the direction indicated by the reference vector). FIG. 10 shows the movement in a direction inclined by a predetermined angle (θ) with respect to the reference vector. Show.

  As shown in FIG. 8, the reader 16 (reading means) provided at the bottom of the moving body 10 reads the tags arranged on the reflecting member over a slightly wide range, and the read tags. Information (unique ID) is transmitted to the control unit 15. In the control unit 15, the position information specifying unit 15 b obtains the coordinate information of each tag from the unique ID of the tag read from the information, and transmits the coordinate information to the calculation unit 15. The calculation unit 15 specifies a polygon on the plane from the read unique ID, and calculates the gravity center position of the polygon according to a predetermined program. Then, the calculated position of the center of gravity is set as the self-position of the moving body 10 when the reader 16 reads these tags.

Next, a method in which the moving body 10 calculates the moving direction will be described.
First, if the mobile in a direction equal to (the direction indicated by the or reference vector) direction perpendicular to the extending direction of the reflecting member is moved, the sensors 17 and 18 of the moving body 10 is provided at a position information supply region R _n It is detected that the light passes over the reflecting member M _n (detection line). At this time, the time measuring unit 15c described above calculates the time difference between the times detected from these sensors. Here, the moving speed of the moving body 10 is v, the interval between the sensors 17 and 18 is d, and the time when the sensor 17 detects the reflecting member _Mn is the first time t1, and the sensor 18 detects the reflecting member _Mn . Let the time be the second time t2. Further, when moving on the reflecting member, the speed change of the moving body 10 is small and can be ignored.

At this time, if the angle formed by the moving direction of the moving body with respect to the reference vector Vn (the angle with respect to the clockwise direction shown in FIG. 10) is θ, the time difference when the sensor 17 and the sensor 18 detect the reflecting member _Mn. Since the distance traveled by the moving body 10 at Δt = t2−t1 is v · (t1−t2), the relationship shown in the following formula 1 is established among d, θ, v, t1, and t2.
tan θ = v · (t2−t1) / d (Formula 1)

Accordingly, the angle θ formed by the moving direction of the moving body with respect to the reference vector Vn is expressed by the following Expression 2.
θ = atan (v · (t2−t1) / d) (Formula 2)

  Based on Equation 2, the calculation unit 15d can calculate an angle formed by the moving body 10 moving with respect to the reference vector.

  FIG. 11 is a graph showing the relationship between the time when the moving body 10 detects the reflecting member and the intensity of the detected signal in the case shown in FIG. As is apparent from FIG. 11, in this case, the times t1 and t2 when the sensors 17 and 18 detect the reflecting member are almost simultaneous, so the time difference Δt (= t2−t1) is regarded as almost 0, and the calculation unit 15d Then, the moving direction of the moving body 10 is calculated to be parallel (θ = 0) to the direction orthogonal to the extending direction of the reflecting member (the direction indicated by the reference vector).

  FIG. 12 is a graph showing the relationship between the time when the moving body 10 detects the reflecting member and the intensity of the detected signal in the case of the example shown in FIG. In this case, since the value of Δt (= t2−t1) has a certain size, the angle formed by the moving direction of the moving body with respect to the direction indicated by the reference vector is calculated.

  In such a case, an upper limit threshold value of Δt (= t2−t1) is set, and when Δt exceeds this threshold value, an error signal indicating that an error has occurred without calculating the angle θ. May be transmitted. In this way, only one of these sensors detects the reflecting member (time t1), and after a while, the other sensor detects the reflecting member when the moving body moves on the reflecting member again. In such a case (time t2), the abnormal angle θ is not output as the moving direction of the moving body.

  In addition, if the value of Δt is negative with respect to the moving direction of the moving body, the value of θ is negative for the angle formed by the moving direction of the moving body with respect to the reference vector Vn. In this case, the obtained angle θ is represented as an angle formed by the moving direction of the moving body 10 counterclockwise with respect to the reference vector. In this way, the direction to be calculated can be accurately determined according to which of the sensors 17 and 18 has detected the detection line (reflecting member) first.

  As described above, the self-position (absolute position) and the movement direction at the time of passing through the position information supply region can be obtained accurately by calculating the self-position and the movement direction of the moving body 10. Based on the above, the moving body can correct its own position and moving direction.

  In the above-described embodiment, as the detection unit, a sensor that irradiates light to the reflecting member and detects that the moving body has passed through the reflecting member by receiving the reflected light is used. The present invention is not limited to this. As another example, a magnetic sensor etc. can also be used as a detection part, for example. In this case, it is possible to detect that the moving body has passed through this region by disposing a magnetized magnetic member instead of the reflecting member in the position information supply region.

  In the above-described example, the movement direction is determined based on the time difference between the times when the sensors 17 and 18 output a detection value greater than or equal to a predetermined value. However, the present invention is not limited to this. . For example, as shown in FIG. 13, the moving direction of the moving body with respect to the direction indicated by the reference vector is determined based on the time difference (Δt ′) when the outputs of the sensors 17 and 18 are over a predetermined value. It can be calculated by the same method.

Furthermore, in the above-mentioned example, the example using the reflecting member that covers the entire position information supply region is described, but the present invention is not limited to this. For example, as shown in FIG. 14, a reflection member M _n ′ as a detection line may be provided at each end of the long side of the position information supply region. By storing the position and shape of such a reflecting member in the storage area of the moving body in advance, from the time when the sensors 17 and 18 pass this reflecting member and the position shape of the reflecting member stored in advance, The moving direction of the moving body can be calculated. When the reflection member is configured in this way, the position information supply region can be further simplified, and therefore the equipment for configuring the mobile control system becomes cheaper.

  In this embodiment, an example is shown in which a plurality (two) of detection units (sensors) for detecting a reflecting member as a detection line are provided, but the present invention is not limited to this, and a single unit It is possible to calculate the angle θ formed by the moving direction of the moving body with respect to the reference vector Vn even using the detection unit (sensor). An example will be described below.

Embodiment 2 of the Invention
In the present embodiment, the moving body 10 ′ includes a single detection unit (sensor 19), and the moving direction of the moving body is calculated using only information output from the sensor 19. FIG. 15 shows a state in which the moving body 10 ′ passes over the reflecting member in the position information supply region in such an embodiment. In this example, each component in the moving body and the position information supply area has substantially the same configuration as that described in the above-described embodiment, and thus detailed description thereof will be omitted.

As shown in FIG. 15, the length of the reflecting member in the direction indicated by the reference vector is w, the time when such a sensor 19 starts detecting the reflecting member is the first time t1 ′, and then the reflecting member Assuming that the time when the detection is finished is the second time t2 ′, these time differences Δt ′ have no speed change when the moving body 10 moves on the reflecting member, and move linearly. With respect to the angle θ ′ formed by the moving direction of the moving body with respect to the reference vector Vn, the relationship shown in the following Expression 3 is established.
cos θ ′ = w / v · Δt ′ (Formula 3)

Therefore, in this case, the angle θ ′ formed by the moving direction of the moving body with respect to the reference vector Vn is expressed by the following Expression 4.
θ ′ = acos (w / v · Δt ′) (Formula 4)

  Thus, by setting the size of the reflecting member and the moving speed of the moving body so that the moving body 10 moves on the reflecting member without changing the speed, it can be regarded that the moving body 10 moves substantially linearly. It is possible to calculate the moving direction of the moving body with respect to the reference vector Vn only by using the sensor.

  As described above, according to the moving body control system configured as described above, it is possible to accurately calculate the moving direction of the moving body simply by providing the position information supply area at an arbitrary place in the moving area. Therefore, the estimated moving direction of the moving object can be corrected based on the calculated direction.

  The above-described embodiments are merely a part of the embodiments according to the present invention, and the present invention is not limited to this. For example, the tags arranged in the position information supply region may be arranged in a single row at equal intervals in the same direction as the direction in which the detection line extends, or may be arranged in a single row or in multiple rows. You may combine with what you did. In this way, since the configuration of the position information supply area can be further simplified, a lower-cost moving body control system can be constructed.

  Alternatively, as shown in FIG. 16, the tags are arranged in a plurality of rows in the same direction as the direction in which the detection line (reflecting member) extends, and these tags are directed in the direction in which the detection line extends. You may arrange | position in what is called a staggered pattern shifted regularly from each other. In particular, when the tag is read by a reader provided on the moving body, it is preferable to consider the position of the tag so that at least one tag can be reliably read even during movement.

  In the above-described embodiment, an RFID tag is used as an example of a tag to be used. However, the present invention is not limited to this, and a wireless ID capable of reading data by a reading unit of a mobile object is used. Any tag can be used.

  In the above-described embodiment, as a method for calculating the self position from the read tag data, a method is used in which the center of gravity of the polygon formed from the coordinates of the plurality of read tags is the self position. The present invention is not limited to this, and a general technique for calculating the self-position using the read tag data can be widely used.

  In the above-described embodiment, the moving direction is calculated on the assumption that the moving speed on the position information supply area is constant, but the moving speed is not necessarily constant. For example, when the moving speed on the position information supply area is not constant, the moving distance is calculated by the value obtained by integrating the speed of the moving body in the time passing through the position information supply area (on the reflecting member). Since it can be calculated, the moving direction can be calculated based on this value.

  In addition, the position of the detection unit provided in the moving body is an example in which the detection unit is provided in the front in the above embodiment, but the position of the detection unit is not particularly limited to this, and the side or It may be provided behind. However, it is more preferable to arrange it symmetrically with respect to the moving direction of the moving body (that is, the direction passing through the center of the moving body and facing the traveling direction of the moving body), because the calculation for calculating the moving direction becomes simple. .

  Further, the means for estimating the self-position and moving direction of the moving body is not limited to the odometry method based on the number of rotations of the wheel, for example, receiving the reflected light of the laser light emitted from the light source, A laser range finder that performs object detection (sensing) based on the so-called TOF (Time of Flight) principle that detects the position of an object reflected by a laser beam based on the time required to receive light, or irradiated ultrasonic waves An ultrasonic sensor that senses the rough shape and position of an object existing in an area irradiated with ultrasonic waves based on the intensity of the received ultrasonic waves, or a combination thereof can be used. . Alternatively, when the moving area of the moving body is indoors, the position and moving direction of the moving body may be estimated by incorporating indoor GPS or the like. It is also possible to use a device that estimates a self-position by optically recognizing a landmark provided at a specific location in a moving area using a camera that optically recognizes the external environment. .

  Further, in the above-described embodiment, an example in which the control unit is incorporated in the moving body is described. However, the present invention is not limited to this, and is for controlling the position and moving direction of the moving body. It is also possible to incorporate the control unit in a base station provided separately from the mobile body. If it does in this way, since the structure of a moving body can be made simpler, it will become possible to reduce the cost of moving body itself.

  Furthermore, such a moving body is not limited to the one on which the operator is boarded, but can also be applied to an AGV that moves along a predetermined movement route. In this case, since the position and direction in which the AGV moves can be obtained more accurately with the simple equipment as described above, the cost required for the equipment in the factory can be reduced.

  In the above-described embodiment, the moving body is a wheel driving type moving body that drives a wheel as an example. However, the moving body is not limited to this. For example, the moving operation is performed according to the created gait data. The present invention can be applied even when a legged mobile robot such as a biped walking type is controlled.

In the moving body control system according to the first embodiment, it is a schematic diagram schematically showing a state in which a moving body 10 moves in a moving area. It is the schematic showing the internal structure of the moving body 10 shown in FIG. 1 simply. FIG. 2 is a schematic side view schematically illustrating an overview configuration of a moving body 10 illustrated in FIG. 1. It is the schematic showing the structure of the sensor with which the moving body 10 shown in FIG. It is a block diagram which shows roughly each structure of the control part contained in the moving body shown in FIG. It is a figure which shows roughly the positional information supply area | region provided in the movement area | region. It is a figure which shows an example of the data structure of the positional information on each tag arrange | positioned at a positional-information supply area | region. It is a figure which shows a mode that the mobile body shown in FIG. 1 passes on the reflection member of a positional information supply area | region, and reads a tag. It is a figure which shows a mode that the mobile body shown in FIG. 1 moves to the direction which a reference | standard vector shows on the reflective member of a positional-information supply area | region. It is a figure which shows a mode that the mobile body shown in FIG. 1 moves to the direction which inclines only a predetermined angle with respect to the reference | standard vector on the reflection member of a positional information supply area | region. 10 is a graph showing the relationship between the time when the moving body detects the reflecting member and the intensity of the detected signal in the example shown in FIG. 9. It is a graph which shows the relationship between the time which a mobile body detects a reflective member in the example shown in FIG. 10, and the intensity | strength of the detected signal. It is a graph which shows the time difference ((DELTA) t ') of the time when the output more than predetermined value of the sensors 17 and 18 was complete | finished. It is a figure which shows the example which provided reflection member _Mn 'in the long side edge part of the positional information supply area | region. It is a figure which shows a mode that the moving direction of a moving body is calculated using the single sensor provided in the moving body in the moving body control system which concerns on 2nd Embodiment. It is a figure which shows the other example which arrange | positions a tag in a positional-information supply area | region.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Mobile body control system 10, 10 '... Autonomous mobile body 10a ... Mobile body main body 11 ... Wheel 13 ... Drive part (motor)
14 ... Counter 15 ... Control unit 15a ... Storage area 16 ... Reader (reading means)
17, 18, 19... Sensor (detection unit)
R: Position information supply region M: Reflecting member (detection line)
T ... tag P ... map information V ... reference vector

Claims (14)

A position information supply area comprising a plurality of tags having unique IDs and a detection line extending in a predetermined direction;
A moving body that includes a reading unit that reads the ID of the tag and a detection unit that detects the detection line, and that moves in a moving area including the position information supply area;
For each of the plurality of tags, a control unit that stores map information in which relative position coordinates with respect to a reference point in a moving region are registered, and a moving body control system comprising:
A position information specifying unit for specifying position information of the read tag from the map information specified from the map information;
A time measurement unit that measures a time difference between a first time at which the detection unit detects the detection line and a second time at which the detection line is detected after the first time;
A moving body control system comprising: a calculating unit that calculates a relative position and direction of the moving body with respect to the reference point based on the specified position information and the measured time difference.   A plurality of the detection units are provided, and the time measurement unit sets a time when the first detection unit detects the detection line among the plurality of detection units as a first time, and other detection units The mobile body control system according to claim 1, wherein a time difference between them is measured as a second time when the detection line is detected.   In the position information supply region, a plurality of detection lines extending in the same direction are provided, and the time when the detection unit detects the first detection line is defined as the first time, and the time when the second detection line is detected. The mobile unit control system according to claim 1, wherein a time difference between them is measured as a second time.   The plurality of tags provided in the position information supply region are arranged at equal intervals in the same direction as the direction in which the detection line extends. Mobile control system.   The mobile body control system according to claim 1, wherein a plurality of the position information supply areas are provided in the movement area.   The mobile body control system according to claim 5, wherein the detection lines provided in the position information supply area are provided so as to extend in different directions for each area.   The mobile body control system according to any one of claims 1 to 6, wherein the tag is a read-only tag.   The mobile tag control system according to any one of claims 1 to 7, wherein the tag is an RFID tag.   The mobile control system according to claim 1, wherein the control unit is incorporated in a mobile body.   The mobile body according to any one of claims 1 to 9, wherein the mobile body includes self-position estimating means, and the self-position estimated by the self-position estimating means is corrected by the recognized self-position. Control system.   The mobile body control system according to claim 10, wherein the self-position estimation unit estimates a self-position by acquiring a moving direction and a distance of the mobile body by an odometry method.   The movement according to any one of claims 1 to 11, wherein the moving body moves on a plane, and is a wheel-type moving body that moves by driving a wheel that contacts the plane. Body control system.   The mobile body control system according to any one of claims 1 to 12, wherein the mobile body is a boarding type mobile body on which a human can be boarded.   The mobile body control system according to claim 13, wherein the mobile body includes an operation unit that designates a destination in a movement area when operated by a person on board.

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