JP4432935B2 - Autonomous mobile body and autonomous mobile body control method - Google Patents

Description

  The present invention relates to an autonomous mobile body that moves on a plane and an autonomous mobile body control method, and more particularly, to an autonomous mobile body and an autonomous mobile body that autonomously move on a movement map specified in the plane. It relates to a control method.

  In recent years, a map having a predetermined area in a plane such as a building or an open space is identified, and on this map, it moves autonomously by means such as wheels or legged walking without requiring human operation. Autonomous mobile bodies to perform are being developed.

In order for such an autonomous moving body to move accurately on a plane, it is preferable to continue to move without slipping on the moving plane. Therefore, in such an autonomous moving body, there are known autonomous moving bodies in which a plurality of types of moving maps that differ only in the friction coefficient on the plane are stored in the autonomous moving body, and movement is performed based on these moving maps. ing. When such an autonomous mobile body slips during movement, the currently used movement map is switched to a map having a low friction coefficient included in the plurality of types of movement maps stored, and the friction coefficient determined by the map is changed. The corresponding movement control is performed. By such movement control, the autonomous mobile body can move without causing slip again after the occurrence of slip. (For example, Patent Document 1)
Japanese Patent Publication No. 7-61781

  However, in the autonomous mobile body as described above, when moving on the same plane repeatedly, if the movement map includes a slippery position, the map having a low friction coefficient after passing through the slippery position. Continue to move with the switch to. Therefore, even when the autonomous mobile body moves in a range where the friction coefficient is large (that is, the possibility of slipping is low) after the slip occurs, the autonomous mobile body moves under the condition for moving in the range where the friction coefficient is small. Will do. That is, once the vehicle slips, the autonomous mobile body selects a speed and a route that does not slip regardless of the position on the plane, and thus a restriction for movement occurs.

  The present invention has been made to solve such a problem, and even when a slippery position is included in the moving plane, the autonomous mobile body and the autonomous movement that hardly cause restrictions on the movement are provided. The object is to provide a body control method.

  An autonomous mobile body according to the present invention is an autonomous mobile body that autonomously moves on a movement map specified in a plane, and a storage unit that stores the movement map, and whether or not a slip has occurred during movement. And a position acquisition unit that acquires a self-position when the determination unit determines that a slip has occurred, and includes a self-position when it is determined that a slip has occurred. A predetermined range is stored on the movement map as a slip position.

  According to the autonomous mobile body as described above, the self-position on the movement map where the slip has occurred is grasped, and the position is stored on the movement map. Therefore, a movement route is created so as to avoid the position where the slip has occurred. can do. Therefore, even when a slippery position is included in the moving plane, it is possible to move autonomously with as little restriction as possible.

  The position acquisition unit may include an absolute position acquisition unit that acquires the absolute position of the position on the movement map. With such an autonomous mobile body, for example, the absolute position of the self when the number of rotations of the wheel changes abruptly can be the position where the slip has occurred.

  In addition, the position acquisition unit may include a self-position calculation unit that calculates a self-position from the direction and distance moved on the movement map. With such an autonomous mobile body, slip occurs during movement, and even if the slipped position and the self-position immediately after the slip are different, the position where the slip occurred is determined regardless of the absolute position immediately after the slip. Can be sought.

  Further, whether or not slip has occurred is determined based on the absolute position acquired by the absolute position acquisition unit and the self position calculated by the self position calculation unit at the time when the absolute position is acquired. It may be a thing. For example, it may be determined whether or not a slip has occurred by comparing the amount of change in absolute position with the amount of change in self-position to be calculated. In such a case, the amount of change in absolute position can be easily determined from the absolute moving speed of the autonomous mobile body, and the amount of change in self-position to be calculated can be easily obtained from information such as the number of rotations of the wheel. Can be easily determined.

  Further, whether or not slip has occurred is determined by determining the amount of positional deviation between the absolute position acquired by the absolute position acquisition unit and the self position calculated by the self position calculation unit at the time when the absolute position is acquired. May be obtained based on the amount of displacement.

  In that case, when the amount of positional deviation is equal to or less than a predetermined threshold, the self-position calculated by the self-position calculating unit is replaced with the absolute position acquired by the absolute position acquiring unit, and the amount of positional deviation exceeds a predetermined threshold In addition, the determination unit may determine that a slip has occurred at the calculated self-position. In the case of such a moving body, when a slight positional deviation where no slip has occurred, the position recognition can be corrected by always replacing the own position with the absolute position, and the slip has occurred. In this case, the slip occurrence position can be accurately obtained.

  In the autonomous mobile body, the predetermined range stored as the slip position is an area specified by a range of a certain distance centered on the calculated self-position where the slip is determined to have occurred. You can also. Thus, by representing the slip position in a range having a predetermined area, it is possible to create a distribution that is close to the slippery range on the actual plane.

  In the autonomous mobile body, the movement map is a grid map created by virtually depicting grid lines connecting lattice points arranged at substantially constant intervals in the plane. It is preferable that the unit grid surrounded by the grid lines is a position where the autonomous mobile body is present, and the slip position is specified by selecting one or more unit grids. Such an autonomous mobile body can easily create a range for specifying a moving route and a slip position.

  Further, the autonomous mobile body creates a movement route that does not pass through a predetermined range in which the slip is determined to occur after the determination unit determines that the slip has occurred, and continues the movement. Also good. In such an autonomous mobile body, it is possible to move along a movement path that avoids a position where slippage is likely to occur on the movement map, and thus it is possible to stably move after slipping.

  In addition, the autonomous mobile body further includes a friction information acquisition unit that acquires friction information generated between the autonomous mobile body and a movement map in a plane when moving, and the storage unit includes a friction information acquisition unit The distribution of the friction information at the slip position obtained based on the friction information acquired by may be stored on the movement map.

  According to such an autonomous mobile body, it is possible to obtain the friction information of the position where the slip has occurred and perform the movement control so that the slip does not occur when passing through the position. There is no need to avoid it, and there are fewer restrictions during movement.

  Further, the distribution of friction information is provisionally defined on the movement map, and the provisional information is obtained using the friction information obtained by the friction information acquisition unit based on the result of the autonomous mobile body moving on the movement map. The distribution of the friction information determined in (1) may be updated. In this way, by adding the newly obtained friction information and updating the friction information distribution, it is possible to always create an appropriate friction information distribution even when the conditions on the movement map change. it can.

  Further, in the autonomous mobile body, the storage unit stores, for each object, an area occupied by the object arranged on the movement map, and the area occupied by the self-position where it is determined that a slip has occurred. The friction information of the self-position may be applied to the entire area occupied by the object to store the distribution of the friction information. In such an autonomous mobile body, with respect to an object having substantially uniform friction information such as a flooring or a carpet arranged on the movement map, the slip position is applied in order to apply one piece of friction information to the entire area of the object. It is possible to efficiently create a friction distribution at.

  The friction information may be a static friction coefficient on a moving plane. As described above, by creating the distribution of friction information based on the static friction coefficient, it is possible to more easily perform movement control for preventing slipping.

  As described above, according to the present invention, it is possible to provide an autonomous mobile body and an autonomous mobile body control method in which movement is not easily restricted even when a slippery position is included in a moving plane. Can do.

Embodiment 1 of the Invention
The autonomous mobile body according to the first embodiment of the present invention will be described below with reference to FIGS. In this embodiment, the autonomous mobile body is an example of a vehicle-type mobile body that autonomously moves on a plane by driving a pair of wheels.
The autonomous mobile body according to the first embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an embodiment in which a vehicle 10 as an autonomous mobile body moves within a limited movement map P (region surrounded by a broken line) on the floor 1 as a moving plane. It is shown schematically. In this embodiment, it is assumed that no object is placed in the movement map P on the plane 1 and that the vehicle 10 can arbitrarily move in the movement map P.

  As shown in FIG. 2, the vehicle 10 is an opposed two-wheel vehicle including a box-shaped vehicle body 10 a, a pair of opposed wheels 11 and 11, and a caster 12, and these wheels 11 and 11, The caster 12 supports the vehicle body 10a horizontally. Furthermore, inside the vehicle 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. A calculation unit 15 is provided that creates and transmits the control signal to the drive units 13 and 13. In a storage area 15a such as a memory as a storage unit provided inside the calculation unit 15, a moving map is provided together with a program for controlling the moving speed, moving direction, moving distance, etc. of the vehicle 10 based on the control signal. The shape and size of P are stored.

  Moreover, the self-position calculation part which calculates the self-position which comprises the position acquisition part with which the vehicle 10 is provided, and the absolute position acquisition part which acquires self-absolute position are comprised as follows.

  That is, the moving speed and the moving distance for calculating the self-position are obtained by integrating the rotation speeds of the wheels 11 and 11 detected by the counter 14 in the calculation unit 15, and thereby the vehicle in the movement map. Ten self-positions (odometry positions) are calculated.

  Furthermore, an antenna (not shown) for acquiring the absolute position of the vehicle body 10a is provided on the upper surface of the vehicle body 10a, and a vehicle absolute position detection means (not shown) using a position estimation method such as a Kalman filter or a particle filter. The position information indicating the absolute position of the vehicle 10 is received. Then, the calculation unit 15 analyzes the position information to recognize its own absolute position. The absolute position detection means as described above may be provided integrally with the vehicle 10 or may be provided outside the vehicle 10. Note that, as means for acquiring the absolute position, an environment recognition sensor that recognizes its own position from the surrounding environment can be used instead of the antenna.

  If the difference between the absolute position of the self obtained from the received position information and the calculated self position is within a predetermined threshold, the calculation unit 15 calculates the self recognized position from the self position calculated. Replace with absolute position. On the contrary, when the difference between the self position and the absolute position obtained by the calculation exceeds the threshold value, it is determined that the slip has occurred, and the self position obtained by the calculation is stored in the storage area 15a as the slip position. Thus, the calculating part 15 acts also as a determination part for determining whether the vehicle 10 slipped.

  Then, after determining that the slip has occurred, the vehicle 10 creates a new movement route with the acquired absolute position as its own position, and continues to move. Details regarding the movement control of the vehicle 10 will be described later.

  Further, a camera 16 for recognizing an obstacle or the like appearing in the moving direction is fixed on the front surface of the vehicle main body 10a. As a result, the moving direction and speed of the vehicle are determined according to the program. The vehicle 10 configured in this manner independently controls the drive amount of the pair of wheels 11 and 11 so that the vehicle travels straight, moves in a curve (turns), moves backward, and rotates on the spot (centering on the middle point of both wheels). ) And other moving operations can be performed. Then, the vehicle 10 autonomously creates a movement route to the designated destination in the movement map P in accordance with a command from the control unit 40 that designates a movement location from the outside, and follows the movement route. To reach the destination.

  Next, a grid map created based on the shape of the movement map P stored in the vehicle 10 will be described.

  In the storage area 15a provided inside the calculation unit 15, grid lines that connect lattice points arranged at substantially constant intervals d (for example, 10 cm) are virtually depicted in the shape of the entire moving map P on the floor 1. The grid map obtained by doing is stored.

  FIG. 3 illustrates an example of the grid map described above. The grid map 20 depicts a grid line 22 that connects lattice points arranged at a substantially constant interval d inside the outer frame 21 simulating the shape of the movement map P. Then, using the grid unit 23 surrounded by the grid line 22, the location corresponding to the vehicle 10's own position, the movement end point that is the destination, and the movement direction of the vehicle 10 at the movement end point are specified. . The interval d can be changed as appropriate according to conditions such as the curvature of the vehicle 10 that can be moved and the accuracy of recognizing the absolute position, and can also be used as a threshold value when it is determined that the vehicle has slipped.

  The calculation unit 15 uses the self-position specified on the grid map 20 as a movement start point, and creates a movement route from this movement start point to the movement end point that is the destination. Then, the vehicle 10 calculates its own position in real time from the moving speed and the moving distance, and moves along the created moving route.

  Next, when there is a position where the slip easily occurs in the movement map P, and the vehicle 10 moves in the movement map P and slips at the position where the slip easily occurs, the position where the slip easily occurs is stored and moved. The procedure for performing is described.

FIG. 4 is a flowchart showing a procedure for recognizing the position of the vehicle 10 when the vehicle 10 moves along the movement route. In this embodiment, the vehicle 10 starts to move from the movement start point Q ₀ , and is positioned along the determined movement route at positions Q ₁ , Q ₂ ,. . . After passing through Q _n−1 , the movement end point Q _n is reached. In addition, the vehicle 10 shall acquire the positional information showing an absolute position of self at a predetermined timing (for example, every 10 [msec]).

As shown in FIG. 4, the vehicle 10 starts moving from the movement start point Q ₀ (step 101). At this time, the calculation unit 15 registers the movement start point Q ₀ on the grid map 20. Then, the vehicle 10 is to move along a travel path, it recognizes the absolute position R _i of the self-receiving position information indicating the absolute position of the self in real time (step 102). The arithmetic unit of the vehicle 10 is located self-position at the time of recognizing the R _i (the odometry position) Q _i, is calculated by using information such as the direction and speed and movement of the wheels (step 103). Then, the degree of positional deviation between the recognized absolute position R _{i of the} self and the position Q _i is compared with a predetermined threshold (step 104), and it is determined whether or not a slip has occurred.

At this time, when the amount of positional deviation between the absolute position R _i and the self position Q _i is equal to or less than a threshold value (grid map interval d in this embodiment), the calculation unit 15 determines that the vehicle 10 is not slipping. simply replacing the position of the self-in position R _i, and continues to move (step 105). On the other hand, when the amount of positional deviation between the absolute position R _i and the self position Q _i exceeds the threshold (interval d), the calculation unit 15 determines that the vehicle 10 has slipped, and uses the calculated self position Q _i as a movement map. The slip position in P is stored (step 115). Then, after replacing its own position to the position R _i (step 116), to create a new movement route to move the end point from the position Ri, corrects the travel path 30 (step 117). When determined whether the slip during the movement has occurred is completed, it is determined whether to end the movement (step 106), steps 102 to move to reach the moving end point Q _n is finished 107 repeat.

As an example showing such a flow, in FIG. 5, after the vehicle 10 starts moving from the movement start point Q ₀ , passes through the position Q ₁ , the position Q ₂ , and the position Q ₃ along the movement path 30, the movement end point is reached. showing how to reach the Q _4. In this example, the vehicle 10 is slipping at position Q _3, it is assumed that the positional deviation amount between the absolute position acquired when passing through the position Q ₃ exceeds the threshold value (e.g., the distance d between the grid lines). In this case, the vehicle 10 stores the position Q ₃ as the slip position 23 on the grid map 20 as shown in FIG. The stored slip position is identified with a single grid that contains the position Q ₃ as shown in FIG. 6 (smallest area surrounded by grid lines). In this way, the slipped position is stored on the grid map, so in the movement control after slipping, a movement route that avoids this position is created, or the speed is reduced only when passing through this position. It is possible to perform route planning such as

The region specified as the slip position is not limited to the single grid as described above, and a wider region may be specified as the slip position. For example, as shown in FIG. 7, all unit grids surrounding a single grid including the position Q ₃ may be set as the slip positions 23. That is, according to the state of the moving plane, the size and shape of the area specified as the slip position can be arbitrarily determined.

  As described above, in this embodiment, when it is determined that a slip has occurred, the position is stored as a slip position on the movement map so that the subsequent movement path is avoided from the slip position. Can be created. Therefore, there is an effect that it is possible to reduce restrictions that occur with respect to the route plan for performing the movement.

Embodiment 2 of the Invention
Next, the autonomous mobile body according to the second embodiment of the present invention will be described with reference to FIGS. 8 and 9. In the present embodiment, the description of the same configuration as that described in the first embodiment will be omitted.

  In the present embodiment, as in the first embodiment described above, when the amount of displacement between the absolute position and the calculated self position (odometry position) exceeds the threshold during movement from the movement start point to the movement end point, Judge that it slipped at its own position. Then, when the position determined to have slipped is stored as the slip position at the corresponding position on the grid map, the static friction coefficient at the slip position is acquired as the friction information at the slip position. Hereinafter, a configuration and a procedure for acquiring a static friction coefficient as friction information will be described in detail.

FIG. 8 is an enlarged view showing that the wheels 11 of the vehicle 10 slip at a position Q _i on the movement map. In this figure, the distance between the wheels 11 forming a pair of the vehicle 10 is 2a, the wheel diameter is 2r, and the mass of the vehicle 10 is m. Further, the vehicle 10 is assumed to move in a circular arc at the position Q _i , the moving speed in the tangential direction (straight direction) at the position Q _i of the vehicle 10 is v, the rotational angular velocity of the vehicle 10 is ω, and the vehicle 10 is The radius of rotation when moving while drawing an arc is ρ. At this time, the centrifugal force F ₁ acting on the vehicle 10 is expressed by the following formula 1.

.... Formula 1

Furthermore, the propulsion of the vehicle 10 and F _2, the resultant force due to a centrifugal force and driving force, since the wheel 11 are believed to slip when exceeding the frictional force on the plane of movement, traction slip position Assuming that the coefficient is μ, the relationship of the following expression 2 is established immediately after slipping.

.... Formula 2

Here, since the propulsive force F ₂ of the vehicle 10 can be obtained in consideration of the torque from the drive unit 13, the reduction ratio, and the wheel diameter, the static friction coefficient μ at the slipped position can be calculated from Equation 2. it can. The static friction coefficient at the slip position obtained in this way is stored on the grid map in correspondence with the slip position, so that conditions such as speed at which slip does not occur when passing through the slip position can be set. It becomes possible to determine more accurately.

Note that the friction information stored in association with the slip position may be a distribution of friction information at the slip position based on the static friction coefficient obtained as described above. That is, when the slip position is specified in a region wider than a single grid, a distribution of friction information (for example, a static friction coefficient) may be created for a part or the whole of this region. For example, it is determined that the slip at the position Q _i, when stored a set of positions Q _i and single grid surrounding this position as the slip position 23, also create a distribution of friction information in the slip position 23 Good. FIG. 9 is an example showing how the friction information distribution is created in the present embodiment, and the static friction coefficient in the single grid 23a including the position Q _i is μ ₁ obtained as described above. The static friction coefficient in the single grid set 23b surrounding the single grid 23a is larger than the μ _{1 and} smaller than the other areas (areas that do not slip and are not specified as slip positions) μ. ₂ , the distribution of friction information is created.

  Note that the calculation method described above is an example as a calculation method for obtaining a static friction coefficient when a moving body that moves by driving a wheel slips, and the static friction coefficient may be obtained using other calculation methods. Needless to say, it is good.

Embodiment 3 of the Invention
Next, the autonomous mobile body according to the third embodiment of the present invention will be described with reference to FIGS. 10 to 12. Also in this embodiment, the description of the same configuration as that described in Embodiments 1 and 2 is omitted.

As shown in FIG. 10, in the present embodiment, in the movement map P on the floor portion 1, surfaces P ₁ and P ₂ having a predetermined area and made of different materials are provided. The surface P ₂ is composed of a plurality of surfaces P ₂ (a) to (c) made of the same material, and these surfaces P ₂ (a) to (c) have different shapes and different areas. Specific examples of the surface of the same material include a floor material surface such as flooring, tatami mat, etc., or a member used by laying on the surface of the floor portion 1 such as a carpet.

The vehicle 10 moves in the movement map P as described above, but corresponds to the planes P ₁ and P ₂ shown in FIG. 10 on the grid map stored in advance in the vehicle 10 as shown in FIG. It is assumed that the regions P ₁₀ and P ₂₀ (P ₂₀ (a), P ₂₀ (b), and P ₂₀ (c)) are specified in advance. The areas P ₁₀ and P ₂₀ may be stored by manual input or the like when the movement map P is stored, or a signal transmission unit such as RFID is provided on the floor material or member forming the surfaces P ₁ and P _2. It is also possible to read the signals emitted from these signal transmitters and store them together with the movement map P.

As shown in FIG. 12, the vehicle 10 as an autonomous mobile body configured in this manner slipped in the plane P ₁ due to a large difference between the calculated self position Q _i and the self absolute position R _i . Is determined, not only the position Q _i but also the entire region P ₁₀ is stored as the same friction information. That is, when the static friction coefficient μ _{i at} the position Q _i is obtained, the static friction coefficient of the entire region P ₁₀ corresponding to the plane P ₁ is stored on the movement map P as μ _i .

Similarly, when it is determined that slip has occurred at the position Q _j included in the surface P ₂ , the friction information such as the static friction coefficient obtained at the position Q _j is used for the entire region P ₂₀ (that is, P ₂₀ (a)). , P ₂₀ (b), P ₂₀ (c)) are expanded and stored. Thus, the friction information such as the static friction coefficient at the position Q _j is expanded to the entire region P ₂₀ corresponding to the surface of the same material (that is, P ₂₀ (a), P ₂₀ (b), P ₂₀ (c)). By doing so, the friction information of the position where the vehicle 10 does not pass can be stored, and the information can be used for movement control after slipping. Therefore, according to the present embodiment, when the information about the surface included in the moving area is known, the distribution of the friction information on the movement map is more efficiently performed based on the friction information obtained during the movement. Can be sought.

  The specific surface in the movement map as described above is not limited to a part of the movement map, and constitutes the entire surface of the movement map, for example, flooring that occupies the entire room. May be.

  The embodiment of the autonomous mobile body and the autonomous mobile body control method according to the present invention described above is merely an example, and the present invention is not limited to this.

  For example, in the above-described embodiment, a vehicle that drives wheels is taken as an example of a self-supporting moving body. Any form is acceptable. If a moving object moves on a plane by driving with a wheel, legged movement, or other methods, even when a slippery position is included in the moving plane, It is possible to reduce the restrictions that occur in the process.

  Further, the grid map has been described as an example of the movement map stored by the self-supporting mobile body. However, the present invention is not limited to this, and for example, a topology map that represents objects on the map as feature points (nodes). Can also be used. When such a map is used, a movement route is created by a link connecting each feature point (node). By providing this node with friction information, the effect of the present invention can be achieved.

  In the above-described embodiment, the example in which the friction information to be acquired is fixed has been described, but the present invention is not limited thereto. That is, when the moving plane is wet and slippery, the present invention is applied even when the moving plane dries and becomes difficult to slip after the autonomous mobile body slips on the road surface. It is possible. In other words, when slipping does not occur after several passes through the place where the slip has occurred, the friction information is updated so as to increase the stored friction coefficient corresponding to the slip position. You can also. If it does in this way, it can prevent that a friction coefficient falls unilaterally by updating friction information only when slipping.

  In the present invention, the static friction coefficient as the friction information stored in the autonomous mobile body is not limited to that obtained by calculation as described above. That is, the friction information may be acquired from previously stored information by knowing the material on the moving plane. For example, by mounting an infrared analysis unit or the like on the autonomous moving body, the material of the moving plane may be simply analyzed, and information such as a static friction coefficient corresponding to the material may be read out.

It is the schematic which shows a mode that the autonomous mobile body which concerns on 1st Embodiment is located on the moving plane. It is the schematic showing the internal structure of the autonomous mobile body shown in FIG. 1 simply. It is a figure showing an example of the grid map memorize | stored in the autonomous mobile body shown in FIG. It is a flowchart which shows the procedure which determines whether it slipped on the plane which moves, when the autonomous mobile body shown in FIG. 1 moves. It is the schematic which shows a mode that the autonomous mobile body shown in FIG. 1 moved on the plane, and slipped. It is the schematic which shows a mode that the mode that the autonomous mobile body shown in FIG. 5 slipped was represented on the grid map. It is the schematic which shows the example which represents the area | region specified as a slip position with the several unit grid on the above-mentioned grid map. It is the schematic which represented a mode that the autonomous mobile body which concerns on 2nd Embodiment calculates the friction information which arises between an autonomous mobile body and the moving plane. It is the schematic which shows a mode that the autonomous mobile body shown in FIG. 8 memorize | stores the static friction coefficient as friction information on a grid map. It is the schematic which represented the mode that the autonomous mobile body which concerns on 3rd Embodiment is located on a plane, a mode which has a predetermined | prescribed area on this plane and a different material exists FIG. It is a figure which shows an example of the grid map memorize | stored in the autonomous mobile body shown in FIG. It is the schematic which shows a mode that a slip position is memorize | stored in the grid map memorize | stored in the autonomous mobile body shown in FIG.

Explanation of symbols

1 ... Floor (plane)
10 ... Vehicle (autonomous mobile body)
10a ... Vehicle body 11 ... Wheel 13 ... Drive unit 15 ... Calculation unit (determination unit)
15a ... Storage area (storage unit)
20 ... Grid map 23 ... Slip position P ... Movement map

Claims (13)

An autonomous moving body that autonomously moves on a moving map specified in a plane,
A storage unit for storing the movement map;
A determination unit for determining whether slip has occurred during movement; and
A position acquisition unit that acquires a self-position when the determination unit determines that slip has occurred ; and
A friction information acquisition unit that acquires a static friction coefficient as friction information generated between the movement map and the autonomous mobile body when moving is provided,
The storage unit stores a predetermined range including a self-position when it is determined that slip has occurred on the movement map as a slip position ,
When the slip position is the first range and the predetermined range surrounding the first range is the second range, the static friction coefficient acquired by the friction information acquisition unit is the first range in the first range. A static friction coefficient of 1 and a static friction coefficient that is larger than the first static friction coefficient and smaller than the static friction coefficient in other ranges is used as a second static friction coefficient in the second range. An autonomous moving body characterized in that a distribution is stored on the moving map.   The autonomous mobile body according to claim 1, wherein the position acquisition unit includes an absolute position acquisition unit that acquires an absolute position of the self on a movement map.   The autonomous mobile body according to claim 2, wherein the position acquisition unit further includes a self-position calculation unit that calculates a self-position from a direction and a distance moved on the movement map.   Whether or not a slip has occurred based on the absolute position of the self acquired by the absolute position acquisition unit and the self position calculated by the self position calculation unit when the absolute position is acquired by the determination unit. The autonomous mobile body according to claim 3, wherein the autonomous mobile body is determined.   The determination unit obtains a positional deviation amount between the absolute position acquired by the absolute position acquisition unit and the own position calculated by the self-position calculation unit at the time when the absolute position is acquired, 5. The autonomous mobile body according to claim 3, wherein it is determined whether or not a slip has occurred. When the positional deviation amount is equal to or less than a predetermined threshold, the self position calculated by the self position calculation unit is replaced with the absolute position acquired by the absolute position acquisition unit,
The autonomous mobile body according to claim 5, wherein when the amount of positional deviation exceeds a predetermined threshold, the determination unit determines that a slip has occurred at the calculated self-position.   7. The predetermined range stored as the slip position is an area specified by a range of a fixed distance centered on a self-position where it is determined that a slip has occurred. The autonomous mobile body described in Crab.   The movement map is a grid map created by virtually depicting grid lines connecting lattice points arranged at substantially constant intervals in the plane, and unit grids surrounded by grid lines on the movement map The autonomous mobile body according to any one of claims 1 to 7, wherein the autonomous mobile body is a position where the autonomous mobile body exists, and the slip position is specified by selecting one or a plurality of the unit grids.   The autonomous mobile body according to any one of claims 1 to 8, wherein after the determination unit determines that a slip has occurred, a movement route that does not pass through the slip position is created and the movement is continued. The friction information distribution is provisionally determined on the movement map, and the provisional determination is performed using the friction information obtained by the friction information acquisition unit based on the result of the autonomous moving body moving on the movement map. The autonomous mobile body according to claim 1, wherein the distribution of the obtained friction information is updated. The storage unit stores, for each object, a region occupied by an object arranged on the movement map, and the self-location is determined to be included in the region occupied by the object when it is determined that slip has occurred. autonomous moving body according to the friction information of the position, to claim 1 0, characterized by storing the distribution of the friction information applies to the entire region occupied by said object. An autonomous moving body control method for controlling an autonomous moving body that autonomously moves on a movement map specified in a plane,
On the movement map, an absolute position information acquisition step for acquiring absolute position information of the autonomous mobile body;
A self-location information calculation step of calculating and acquiring self-location information of the autonomous mobile body from the direction and distance in which the autonomous mobile body has moved on the movement map;
A positional deviation amount calculating step for calculating a positional deviation amount between the absolute position of the acquired autonomous mobile body and the self-position of the autonomous mobile body acquired by the calculation;
A determination step of determining whether or not a slip has occurred based on the calculated amount of displacement;
A storage step of storing a predetermined range including the self position on the movement map as a slip position when it is determined that a slip has occurred;
A friction information acquisition step of acquiring a static friction coefficient as friction information generated between the movement map and the autonomous mobile body when moving on the movement map;
When the slip position is the first range and the predetermined range surrounding the first range is the second range, the static friction coefficient acquired at the slip position is the first range in the first range. The distribution of friction information is defined as a static friction coefficient, a static friction coefficient that is larger than the first static friction coefficient and smaller than the static friction coefficient in the other ranges, and a second static friction coefficient in the second range. And a friction information storage step for storing the information on the movement map . Wherein after it is determined that a slip has occurred at decision step, to create a movement path which does not pass through the slip position, the autonomous moving body control method according to claim 1 2, characterized in that to continue to move.