JP4445210B2 - Autonomous robot - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention autonomous cleaning target area, to the autonomous mobile robot for performing cleaning while creating a map.
[0002]
[Prior art]
Conventionally, an autonomous mobile robot stores a map of a work area created in advance, and performs work by traveling through the work area while referring to the map based on a work plan, or 1 around the work area in advance. It is known that a map of a work area is created and stored around the work area, and the work is performed by running through the work area while referring to the map based on the work plan (see, for example, Patent Document 1).
[0003]
[Patent Document 1]
JP 05-46239 A (paragraphs “0012” to “0024”, etc.)
[0004]
[Problems to be solved by the invention]
However, in the case of creating a map by making one round around the work area in advance, it takes time and effort to create the map, especially when creating a map of a work area having a complicated shape in advance. There is a problem that it takes time and it takes a long time to finish the actual work.
The present invention provides an autonomous traveling robot that can clean a cleaning area in a short time without storing a map of the cleaning area in advance.
[0005]
[Means for Solving the Problems]
The present invention comprises travel means and cleaning means,
In the autonomous traveling robot that cleans the area to be cleaned by the cleaning means while traveling autonomously straight by the traveling means,
Self-position estimating means for calculating a movement amount and a moving direction of the traveling means by a calculating means, and always estimating a current position of the traveling means based on the calculation result;
Obstacle detection means for detecting an obstacle present in the cleaning target area;
The area to be cleaned is divided into cells, and at the time of cleaning, the obstacle detected by the obstacle detection means in this area to be cleaned and the position cleaned by the cleaning means are created for each cell. a is the uncleaned area the cleaning target region as a map, already cleaned areas, and attribute map in which the obstacle detecting means is managed with the attribute of the wheelchair-stranded region is a position in which an obstacle is detected, the cleaning object be one that creates a potential map to potential path length to an arbitrary position from the position that is in the region, a potential according to the potential map is the potential of the current position as a first predetermined value, away from now distance "1" sequentially larger from a position running prohibition port in each cell of the potential maps the equivalent to when the wheelchair-stranded region Together they give Nsharu, and mapping means for providing a travel-restricted potential around the cell units gave travel-restricted potential so as not too close to the wheelchair-stranded regions,
The attribute map and the potential map created by the map creating means are recorded, the current position of the traveling means estimated by the self-position estimating means is recorded, and when the cleaning means starts cleaning, the attribute Map storage means in which a map is initialized, and all the cleaning target areas are uncleaned areas;
In the attribute map initialized by the cleaning means starting cleaning, the closest uncleaned cell of the attribute map is recognized from the current position of the traveling means based on the potential map stored in the map storage means. Recognition means;
When the obstacle detecting means detects an obstacle ahead in the traveling direction, an uncleaned area is searched from the attribute map using the potential map, and is recorded as a non-runnable area for the obstacle in the attribute map. When the cell of the potential map corresponding to the position is set as a travel prohibition potential, and searching for the nearest uncleaned cell, the nearest cell in the uncleaned area is set as a destination point, and travel control is performed on the shortest route there, Among the uncleaned cells of the attribute map of the map storage means, plan a path in which the potential sequentially decreases from the current position of the travel means to the cell having the lowest potential of the potential map of the map storage means, Control means for running control so as to follow the planned route in reverse order;
A potential map is used to move the robot to the nearest uncleaned cell, and a path to reach the robot position by following the cell so that the potential decreases in order from the potential at the destination point is calculated. The autonomous traveling robot is characterized in that it travels by following the calculated route in reverse.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, the present invention is applied to a self-propelled cleaning robot.
[0007]
FIG. 1 and FIG. 2 are diagrams showing the configuration of a self-propelled cleaning robot, and an operation in which various buttons, a display, and the like are provided on the front upper portion of a housing 1 having a substantially circular lower portion and a substantially hemispherical upper portion. A panel 2 is arranged, a bumper 3 is provided in the lower part of the casing 1 from the front surface to the side surface, and a plurality of obstacle sensors 4 including ultrasonic sensors are arranged on the bumper 3 as obstacle detection means. . For example, three obstacle sensors 4 are disposed at a position that can be seen from the front surface with a predetermined interval, and two obstacle sensors 4 are disposed on the left and right side surfaces with a predetermined interval. The obstacle sensor 4 detects front and left and right obstacles.
[0008]
Housed in the housing 1 are a cleaner motor 5, a fan 6 that rotates with the motor 5, and a dust collection chamber 8 that sucks and collects dust from a suction port 7 provided at the bottom by the rotation of the fan 6. Has been.
[0009]
Further, left driving wheel 9a and right driving wheel 9b are respectively attached to the left and right of the center of the bottom of the housing 1, and the driving wheels 9a and 9b are driven to rotate by the left traveling motor 10a and the right traveling motor 10b, respectively. ing. The drive wheels 9a and 9b and the travel motors 10a and 10b constitute travel means. The rotations of the drive wheels 9a and 9b are detected by the rotary encoders 11a and 11b, respectively.
[0010]
At the center of the rear end of the bottom of the housing 1 is attached a swivel wheel 12 that can freely rotate and turn freely in the right and left directions. The housing 1 houses a circuit board 13 in which control circuit components such as a CPU, a ROM, and a RAM are incorporated, and a battery 14 that supplies power to each unit.
[0011]
FIG. 3 is a block diagram showing the configuration of the control unit, 21 is a CPU constituting the control unit main body, 22 is a ROM storing a program for controlling the respective units by the CPU 21, and 23 is a memory storing various data. RAM. Reference numeral 24 denotes a motor control unit 25 that controls the rotation of the operation panel 2, the obstacle sensor 4, and the cleaner motor 5, a motor control unit 26 that controls the rotation of the left and right traveling motors 10a and 10b, and the left and right encoders 11a and 11b. It is an I / O port that performs signal input / output control. The CPU 21 is electrically connected to the ROM 22, RAM 23, and I / O port 24 via a bus line 28.
[0012]
FIG. 4 is a functional block diagram functionally showing the configuration of the control unit. This cleaning robot is functionally composed of the RAM 23 and receives a backup of power by the battery 14, the CPU 21, A control unit 32 formed of a composite of the ROM 22 and the I / O port 24 is included.
[0013]
The storage unit 31 is provided with a map storage unit 311 for storing a map created for the area to be cleaned .
The control unit 32 calculates a movement amount and a movement direction from outputs of the travel control unit 321 that controls the motor control unit 26, the left encoder 11a , and the right encoder 11b, and the calculated movement amount and movement direction. The self-position estimating unit 322 for estimating the current position from the above, the cleaner control unit 323 for controlling the motor control unit 25, the area to be cleaned is divided into cell units, and the obstacle sensor 4 is placed in the area to be cleaned during the cleaning operation. There is provided a map creation unit 324 to create a map (map) to record the position becomes an obstacle, and already cleaned detected in cell units.
[0014]
When the cleaning robot starts cleaning, it first initializes the map in the map storage unit 311. Two maps are prepared, the attribute map MA1 shown in FIG. 5 and the potential map MA2 shown in FIG. These maps MA1 and MA2 divide the work target area into cells.
[0015]
The attribute map MA1 is a map that manages work target areas with attributes of an uncleaned area, a cleaned area, and an unrunnable area, and the corresponding cells are referred to as an unworked cell, an unworked cell, and an unrunnable cell, respectively. The potential map MA2 is a map that expresses a path length from a certain position to an arbitrary position in the work target area as a potential.
[0016]
When the cleaning robot initializes the map, it performs the traveling control shown in FIG. First, in S1, the traveling direction is adjusted. This turns the left and right traveling motors 10a, 10b so that the front faces in the direction of travel. Subsequently, in S2, the left and right traveling motors 10a and 10b are drive-controlled to perform straight traveling. At the same time, the cleaner motor 5 is driven and controlled to clean the floor. In S3, when the obstacle sensor 4 detects that there is an obstacle such as a wall in front, it travels to the vicinity of the obstacle and then stops traveling.
[0017]
In this operation, the cleaning robot always estimates the self-position by the self-position estimation unit 322, detects the presence or absence of front and left obstacles by the obstacle sensor 4, and displays the cleaned area and obstacle in the attribute map MA1. The position of the object is recorded as a travel impossible area. In the attribute map MA1, all are uncleaned areas at the initialization stage.
[0018]
When an obstacle is detected and stopped, in S4, the nearest uncleaned area is searched from the attribute map MA1. The search for the uncleaned area uses the potential map MA2. That is, as shown in FIG. 6, a potential map centered on the current position of the cleaning robot RC is created. Here, the potential of the current position of the cleaning robot RC is set to −1, and the potential is sequentially increased from “1” as the distance increases.
[0019]
In addition, for example, infinity ∞ is given as a travel prohibition potential to the cell of the potential map MA2 corresponding to the position recorded as the travel impossible area due to the obstacle in the attribute map MA1. Further, a margin is provided so that the cleaning robot RC does not get too close to the untravelable area. That is, the travel prohibition potential is also applied to the cells around the cell to which the travel prohibition potential is applied.
[0020]
Therefore, if the cleaned area recorded in the attribute map MA1 is the area M1 indicated by diagonal lines in the figure, the non-running area is the area M2 indicated by cross in the figure, and the uncleaned area is the area M3 indicated by white in the figure. Then, it is determined that there is an uncleaned area, and the nearest uncleaned cell is searched for in the uncleaned area M3. The closest uncleaned cell is the cell having the smallest potential in the uncleaned region in the potential map MA2. In FIG. 6, the cell has a potential of “8”.
[0021]
When the nearest uncleaned cell is searched, subsequently, point-to-point travel control (hereinafter referred to as PTP travel control) is performed in S5. That is, the cleaning robot RC makes a plan to travel to the nearest cell in the uncleaned area M3 using the shortest route there. This plan uses the potential map MA2. That is, the shortest route can be obtained by calculating a route that reaches the current position by following the cell so that the potential decreases in order from the potential “8” of the destination point. Then, the vehicle travels in the reverse direction as shown by the arrow in FIG. Thereby, the cleaning robot RC can be moved to the nearest uncleaned cell in the uncleaned area M3 by a shortest route while bypassing the untravelable area M2.
[0022]
When the PTP travel control in S5 is completed, the process returns to S1 again to adjust the traveling direction and repeats straight travel. When it is determined in S4 that the uncleaned area M3 has disappeared, the series of cleaning controls is terminated.
[0023]
For example, it is assumed that a rectangular room having a pair of obstacles 42 and 43 protruding from the opposite surface of the wall 41 is cleaned as shown in FIG. The X axis and Y axis are determined for this room as shown in the figure.
[0024]
First, the cleaning robot RC adjusts the traveling direction to the positive direction of the Y-axis at the A position in the lower left corner, performs straight travel toward the B position, and performs cleaning. Eventually, an obstacle is detected ahead and stops at the B position.
[0025]
Then, the nearest uncleaned cell is searched. Since the nearest uncleaned cell at this time is the cell on the right, the cleaning robot RC turns 90 degrees to the right and moves to that cell. At this position, the traveling direction is adjusted to the negative direction of the Y axis, and the vehicle travels straight toward the C position for cleaning. Eventually, an obstacle is detected ahead and stops at position C.
[0026]
Then, the nearest uncleaned cell is searched. Since the nearest uncleaned cell at this time becomes the cell on the left side, the cleaning robot RC turns 90 degrees to the left and moves to that cell. At this position, the traveling direction is adjusted to the positive direction of the Y axis, and the vehicle travels straight toward the D position for cleaning.
In this way, in the work area where the continuous uncleaned area continues, the cleaning robot RC performs cleaning while performing general zigzag traveling by this series of travel control, and at the same time the cleaned area M1 and the unmovable in the attribute map MA1. Record area M2.
[0027]
When the cleaning robot RC reaches the D position, it searches for the nearest uncleaned cell, but there is no adjacent uncleaned cell on either side of the D position. At this time, the E position is searched as the nearest uncleaned cell. Then, it moves from the D position to the E position by PTP travel control.
[0028]
When the cleaning robot RC reaches the E position, it moves straight after adjusting its traveling direction, and when an obstacle is detected ahead, it searches for the nearest uncleaned cell and moves to that position by PTP travel control. This series of operations is repeated to perform cleaning while running as indicated by arrows in the figure. When the position F is reached, the closest uncleaned cell is searched at this position, but here there are uncleaned cells at equidistant positions on both the left and right sides. In order to cope with such a case, a default rule for giving priority to positive or negative of the X axis or the Y axis is determined in advance. For example, when priority is given to the negative direction of the X axis, the cleaning robot RC turns 90 degrees to the left and moves to that cell. At this position, the traveling direction is adjusted to the negative direction of the Y axis, and the vehicle travels straight toward the G position for cleaning. Eventually, an obstacle is detected ahead and stops at the G position.
[0029]
Then, the nearest uncleaned cell is searched. Since the nearest uncleaned cell at this time is the H position on the left side, the cleaning robot RC is turned 90 degrees to the left and moved to the H position by the PTP travel control. Clean in the positive direction of the shaft and go straight to the I position. When the position reaches the position I in this way, all the work target areas are the cleaned area and the non-running area, so that there is no uncleaned area and the cleaning ends.
[0030]
FIG. 9 is a view showing a recording state of the attribute map MA1 when the room having the layout shown in FIG. 8 is cleaned. The whole cell division is a work target area, and initially all are uncleaned areas M3. . Then, the cleaning robot RC starts moving from the A position and performs cleaning to record the cleaned area M1, and the obstacle sensor 4 detects the obstacle and records it as the travel impossible area M2.
[0031]
Therefore, when the cleaning robot RC reaches the H ′ position before the I position, the recording state of the attribute map MA1 is as shown in FIG. At this time, since the front wall has not been detected by the obstacle sensor 4, all the areas shown in white are uncleaned areas M3. Thereafter, when the cleaning robot RC runs, the wall on the right side is detected as an obstacle, and when the front wall where the cleaning robot RC has reached the I position is detected as an obstacle, the area around the cleaned region M1 is All are surrounded by a travel impossible area M2. At this time, since the cleaning robot determines that it cannot move outside the non-travelable area M2, the uncleaned area M3 outside the non-travelable area M2 is regarded as the same as M2. As a result, it is determined that there is no uncleaned area, and cleaning is terminated.
[0032]
Thus, instead of cleaning after creating a map of the work area in advance, a map is created while filling each cell of the work target area as a cleaned area and a non-running area while cleaning, and the uncleaned area is Since the cleaning is finished when it disappears, the cleaning work can be performed in a short time. In addition, since cleaning is performed while always checking the uncleaned area, the uncleaned area is not left and reliable cleaning can be performed.
[0033]
In addition, the potential map MA2 is used to move the cleaning robot RC to the nearest uncleaned cell, and a path to reach the position of the cleaning robot CR by following the cell so that the potential decreases in order from the potential at the destination point. Since it calculates and travels by following the calculated route in reverse, it can move to the nearest cell in the target uncleaned region by the shortest route, and therefore can move in a short time.
[0034]
FIG. 10 shows a cleaning path in the case where a U-shaped obstacle 44 is present in a rectangular room surrounded by a wall 41. The X axis and the Y axis are determined for this room as shown in the figure.
[0035]
First, the cleaning robot RC adjusts the traveling direction to the positive direction of the Y-axis at the A position in the lower left corner, performs straight travel toward the B position, and performs cleaning. Eventually, an obstacle is detected ahead and stops at the B position. Then, the next cell to the right is searched for as the nearest uncleaned cell, and the cleaning robot RC turns 90 degrees to the right and moves to that cell. At this position, the traveling direction is adjusted to the negative direction of the Y axis, and the vehicle travels straight toward the C position for cleaning. Eventually, an obstacle is detected ahead and stops at position C.
[0036]
Then, the left adjacent cell is searched for as the nearest uncleaned cell, and the cleaning robot RC turns 90 degrees to the left and moves to that cell. At this position, the traveling direction is adjusted to the positive direction of the Y axis, and the vehicle travels straight to perform cleaning. Then, since the obstacle sensor 4 detects the obstacle 44 at the D position, the cleaning robot RC stops.
[0037]
Here, the right adjacent cell is searched as the nearest uncleaned cell, and the cleaning robot RC turns 90 degrees to the right and moves to that cell. At this position, the traveling direction is adjusted to the negative direction of the Y axis, the vehicle travels straight, cleaning is performed, the wall 41 is detected forward, and the vehicle stops at the E position.
In this way, when the cleaning robot RC detects an obstacle ahead, the cleaning robot RC searches for the nearest uncleaned cell, performs cleaning while traveling by PTP travel control, and also includes a cleaned region M1 and a travel impossible region M2 in the attribute map MA1. Record.
[0038]
When the cleaning robot RC eventually reaches the F position, it searches for the nearest uncleaned cell at this position, but here there are uncleaned cells at equidistant positions on both the left and right sides. For example, if priority is given to the negative direction of the X axis, the cleaning robot RC turns 90 degrees to the left and moves to that cell. At this position, the traveling direction is adjusted to the negative direction of the Y axis, the vehicle travels straight, cleaning is performed, the obstacle 44 is detected forward, and the vehicle stops at the G position.
[0039]
After that, the cleaning robot RC performs cleaning while traveling, and records the cleaned area M1 and the untravelable area M2 in the attribute map MA1. When the position H is reached, there are no uncleaned cells on both the left and right sides, and the cleaning robot RC searches the I position as the nearest uncleaned cell and moves to that position by PTP travel control.
[0040]
The cleaning robot RC that has reached the I position travels straight in the negative direction of the Y axis, performs cleaning, detects an obstacle 44 in the front, and stops at the J position. The closest uncleaned cell is searched at this J position, but it is not in the immediate vicinity, and the K position is searched as the closest uncleaned cell. The cleaning robot RC moves from the J position to the K position by PTP travel control.
[0041]
When the position K is reached, the direction is changed 90 degrees to the right, the direction of travel is adjusted to the negative direction of the Y-axis, and straight ahead is performed for cleaning. Eventually, the wall 41 is detected forward and stops at the L position. The nearest uncleaned cell is searched, but the remaining uncleaned area is only in the vicinity of the M position, and the cleaning robot RC reverses the direction and runs straight in the positive direction of the Y axis to perform cleaning. Then, when the obstacle sensor 4 detects the wall 41 at the M position, the cleaning robot RC stops. When the position M is reached, all the work target areas are the cleaned area and the non-running area, so that there is no uncleaned area and the cleaning ends.
[0042]
Thus, even if the layout of the room to be cleaned is complicated, it can be reliably cleaned in a short time.
In this embodiment, the present invention is applied to a cleaning robot. However, the present invention is not limited to this. The present invention can also be applied to a robot that performs other work than cleaning while traveling.
[0043]
【The invention's effect】
As described above in detail, according to the present invention, it is possible to provide an autonomous traveling robot that can clean a cleaning area in a short time without storing a map of the cleaning area in advance.
[Brief description of the drawings]
FIG. 1 is a front view showing an external configuration of a cleaning robot according to an embodiment of the present invention.
FIG. 2 is a partially cutaway side view showing the internal configuration of the cleaning robot according to the embodiment.
FIG. 3 is a block diagram showing a hardware configuration of a control unit in the embodiment.
FIG. 4 is a functional block diagram functionally showing the configuration of a control unit in the embodiment.
FIG. 5 is a view showing an example of an attribute map formed in the map storage unit in the embodiment.
FIG. 6 is a diagram showing an example of a potential map formed in the map storage unit in the embodiment.
FIG. 7 is a flowchart showing travel control of the cleaning robot in the embodiment.
FIG. 8 is a diagram showing an example of cleaning running by the cleaning robot in the embodiment.
9 is a diagram showing a recording state of an attribute map in the cleaning traveling example of FIG.
FIG. 10 is a diagram showing another example of cleaning running by the cleaning robot in the embodiment.
[Explanation of symbols]
4 ... Obstacle sensor, 5 ... Cleaner motor, 9a, 9b ... Drive wheel, 10a, 10b ... Travel motor, 11a, 11b ... Rotary encoder, 21 ... CPU, 22 ... ROM, 23 ... RAM, 311 ... Map storage unit 321... Traveling control unit 322. Self-position estimation unit 323. Cleaner control unit 324.

Claims (1)

It has traveling means and cleaning means,
In the autonomous traveling robot that cleans the area to be cleaned by the cleaning means while traveling autonomously straight by the traveling means,
Self-position estimating means for calculating a movement amount and a moving direction of the traveling means by a calculating means, and always estimating a current position of the traveling means based on the calculation result;
Obstacle detection means for detecting an obstacle present in the cleaning target area;
The area to be cleaned is divided into cells, and at the time of cleaning, the obstacle detected by the obstacle detection means in this area to be cleaned and the position cleaned by the cleaning means are created for each cell. a is the uncleaned area the cleaning target region as a map, already cleaned areas, and attribute map in which the obstacle detecting means is managed with the attribute of the wheelchair-stranded region is a position in which an obstacle is detected, the cleaning object be one that creates a potential map to potential path length to an arbitrary position from the position that is in the region, a potential according to the potential map is the potential of the current position as a first predetermined value, away from now distance "1" sequentially larger from a position running prohibition port in each cell of the potential maps the equivalent to when the wheelchair-stranded region Together they give Nsharu, and mapping means for providing a travel-restricted potential around the cell units gave travel-restricted potential so as not too close to the wheelchair-stranded regions,
The attribute map and the potential map created by the map creating means are recorded, the current position of the traveling means estimated by the self-position estimating means is recorded, and when the cleaning means starts cleaning, the attribute Map storage means in which a map is initialized, and all the cleaning target areas are uncleaned areas;
In the attribute map initialized by the cleaning means starting cleaning, the closest uncleaned cell of the attribute map is recognized from the current position of the traveling means based on the potential map stored in the map storage means. Recognition means;
When the obstacle detecting means detects an obstacle ahead in the traveling direction, an uncleaned area is searched from the attribute map using the potential map, and is recorded as a non-runnable area for the obstacle in the attribute map. When the cell of the potential map corresponding to the position is set as a travel prohibition potential, and searching for the nearest uncleaned cell, the nearest cell in the uncleaned area is set as a destination point, and travel control is performed on the shortest route there, Among the uncleaned cells of the attribute map of the map storage means, plan a path in which the potential sequentially decreases from the current position of the travel means to the cell having the lowest potential of the potential map of the map storage means, Control means for running control so as to follow the planned route in reverse order;
A potential map is used to move the robot to the nearest uncleaned cell, and a path to reach the robot position by following the cell so that the potential decreases in order from the potential at the destination point is calculated. An autonomous traveling robot characterized in that the vehicle travels by following the calculated route in reverse.

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