JP3660042B2 - Cleaning robot control method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control method for a cleaning robot that autonomously travels on a floor surface and performs automatic cleaning.
[0002]
[Prior art]
In recent years, a cleaning robot having both an autonomous running function and an automatic cleaning function has been proposed. For example, in Japanese Patent Laid-Open No. 4-260905, a cleaning liquid is included in the function of autonomous driving with a motor using a storage battery as a power source, a steering wheel, various sensors for detecting a direction, a microcomputer for controlling these elements, and the like. There is described a cleaning robot having an automatic cleaning function having a sprinkling port for spraying water on the floor, a cleaning brush for cleaning the floor, a suction nozzle for sucking dust, a squeegee for sucking sewage after cleaning, and the like. In addition, as described in Japanese Patent Application No. 6-221766, other conventional cleaning robots also run along a wall on a floor surface having walls on both sides like a corridor.
[0003]
[Problems to be solved by the invention]
However, the conventional cleaning robot has the following problems. As shown in FIG. 13, when the wall 1 is not flat and there is an obstacle such as a protrusion 2, the cleaning robot 3 is avoided by spinning the cleaning robot 3 four times to avoid any obstacle. The efficiency was drastically reduced.
[0004]
The present invention provides a control method for a cleaning robot capable of improving the cleaning efficiency by performing an avoidance operation according to an obstacle even when the wall has a small obstacle such as a protrusion or a large obstacle. The purpose is to provide.
[0005]
[Means for Solving the Problems]
A cleaning robot control method according to the present invention is a cleaning robot control method for avoiding an obstacle when the cleaning robot is running along a wall. In the cleaning robot control method, a first obstacle detection sensor that detects an obstacle in front of the cleaning robot; The cleaning robot is provided with a second obstacle detection sensor that detects a front obstacle and has a detection distance shorter than that of the first obstacle detection sensor, and an inter-wall distance detection sensor that measures a distance to the wall. A step of running to keep the distance to the wall at the first distance, and when the first obstacle detection sensor detects an obstacle, the distance to the wall detected by the inter-wall distance detection sensor is the first distance A step of performing a primary avoidance operation for running at a second distance farther than a distance of 1, and after the first avoidance operation, when the second obstacle detection sensor detects an obstacle, the cleaning robot Stop running And performing a secondary avoidance operation of performing a spin turn at a predetermined angle, and after performing the primary or secondary avoidance operation, when no obstacle is detected forward, the obstacle is avoided by the rear wall detection sensor. And confirming that the vehicle has traveled to keep the distance to the wall at the first distance.
[0006]
The spin turn in the secondary avoidance operation includes a first spin turn performed at a first angle, and when the second obstacle detection sensor detects an obstacle after performing the first spin turn, A second spin turn performed at a second angle larger than the first angle may be included.
[0007]
According to another cleaning robot control method of the present invention, a first obstacle detection sensor that detects an obstacle ahead and a first obstacle detection sensor that detects an obstacle ahead and has a shorter detection distance than the first obstacle detection sensor. The obstacle detection sensor of 2, a wall distance detection sensor for measuring the distance to the wall, and a direction sensor for detecting the traveling direction are provided in the cleaning robot, and the cleaning robot has a target traveling direction and a first distance between the walls. The cleaning robot is set such that the travel direction detected by the azimuth sensor maintains the target travel direction, and the distance to the wall detected by the inter-wall distance detection sensor maintains the first inter-wall distance. When the first obstacle detection sensor detects an obstacle, and the traveling direction detected by the azimuth sensor is shifted toward the wall closer than the target traveling direction, This deviation angle is A step of changing the setting so as to maintain a second inter-wall distance larger than the first inter-wall distance, and a case where the first obstacle detection sensor detects an obstruction when the angle is equal to or smaller than a predetermined approach angle; When the traveling direction detected by the azimuth sensor deviates toward the wall from the target traveling direction, and the deviation angle is larger than the predetermined approach angle, the second obstacle When the obstacle detection sensor detects an obstacle, the cleaning robot stops running, makes a first angle spin turn in the direction in which the distance to the wall increases, and the second obstacle detection sensor further detects an obstacle. Comprises spin-turning a second angle greater than the first angle.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a control method for a cleaning robot according to an embodiment of the present invention will be described.
First, an outline of an operation for avoiding an obstacle by the control method of the present embodiment will be described.
[0009]
As shown in FIG. 3, the cleaning robot 10 is provided with various sensors for detecting an obstacle and detecting a distance to the obstacle. At the front center of the cleaning robot 10, a front obstacle sensor 17b1 for detecting an obstacle in the front range of 300 to 2500 mm and a front obstacle sensor 17b2 for detecting an obstacle in the range of 300 mm or less are provided. Yes. Similarly, on both the left and right sides of the cleaning robot 10, front obstacle sensors 17a1 and 17c1 that detect obstacles in the range of 300 to 2500 mm, front obstacle sensors 17a2 that detect obstacles in the range of 300 mm or less, and 17c2.
[0010]
Further, as shown in FIG. 4, the front obstacle sensors 17b1 and 17b2 located in the center are wide-angle sensors having a wide detection range, and almost all obstacles included in the full width range of the cleaning robot 10 are detected. Can be detected. Conversely, the front obstacle sensors 17a1 and 17a2 and the front obstacle sensors 17c1 and 17c2 provided on the left and right sides have a narrow detection range so that they do not spread outward as much as possible than the width of the cleaning robot 10. There is a need.
[0011]
Furthermore, a left wall detection sensor 23b and a right wall detection sensor 23a for measuring the distances to the left and right walls are provided near the front center of the cleaning robot 10, and the cleaning robot 10 is provided near the rear center. A rear left wall detection sensor 26b and a rear right wall detection sensor 26a for confirming that an obstacle has been avoided are arranged. While detecting an obstacle using such a sensor, traveling is controlled as follows.
(1) The traveling starts with the cleaning robot 10 separated from the wall by about 150 mm.
[0012]
There are small irregularities such as doorways, door knobs and stoppers near the wall, but most of them are in the range of 100 mm. Furthermore, it is necessary to consider that the detection range of the obstacle sensor is slightly wider than the width of the cleaning robot 10. Therefore, the cleaning robot 10 is separated from the wall by about 150 mm in advance so that it can travel without performing unnecessary avoidance operations by detecting small irregularities near the wall as an obstacle.
(2) When the cleaning robot 10 detects an obstacle in front of a long distance during traveling, the traveling speed is decreased and the traveling direction is decreased, and the traveling direction of the cleaning robot 10 with respect to the wall is determined. As shown in FIG. 5A, when the angle approaching the right wall 1a is 2 degrees or less, the setting is changed so as to maintain a distance of 300 mm to the right wall 1a. When traveling a distance of 2500 mm that can be detected by the front obstacle detection sensors 17a1 to c1, the distance approaching this distance is 90 mm (= 2500 * tan 2deg), and the right wall 1a is misidentified as an obstacle. Absent. As shown in FIG. 5B, the same applies to the case of approaching the left wall 1b. As shown in FIG. 6, the distance to the left wall 1b is set to 300 mm.
[0013]
In addition to unevenness such as the door knob described above, a digestive organ may be present near the wall. However, the convex amount of a general digestive organ is within 300 mm. Therefore, after the obstacle is detected, the obstacle such as a digestive organ is avoided by traveling with the distance between the walls set to 300 mm.
(3) When the vehicle runs with the distance between the walls set to 300 mm and no obstacle is detected ahead, it is determined that the avoidance operation has been completed, and the vehicle is returned to the normal traveling speed. Thereafter, it is confirmed that the obstacle has been avoided by the rear right wall detection sensor 26a or the rear left wall detection sensor 26b, and the distance between the walls is returned to 150 mm to resume traveling.
(4) If an obstacle is still detected ahead even if the distance between walls is set to 300 mm, the cleaning robot stops traveling when the obstacle sensor with a short detection distance detects the obstacle. Make an in-situ spin turn at an angle of 2 degrees when stopped. Here, the reason why the spin turn is performed at an angle of 2 degrees is to reduce the amount of change of the course as much as possible according to the size of the obstacle, and there may be a change of ± 1 degree.
(5) If there is no obstacle ahead, it is determined that the operation for avoiding the obstacle has been completed, and the routine returns to the normal traveling operation. More specifically, as shown in FIG. 7, after confirming by the rear left wall detection sensor 26b that an obstacle was avoided by performing two spin turns, the distance to the left wall 1b is maintained at 150 mm. Travel like so.
(6) As shown in FIG. 8, when an obstacle of 300 mm or more exists on the left wall 1b, a 90 degree spin turn is performed four times to avoid it.
[0014]
Next, FIG. 1 shows a configuration of a control mechanism of a cleaning robot to be controlled by the control method according to the present embodiment, and FIG. 2 shows a configuration of a cleaning robot equipped with this control mechanism.
[0015]
As shown in FIG. 2, the right wheel 12a and the left wheel 12b are arranged in the cleaning robot 10 that is self-propelled in the direction of the arrow A, and are rotated by the right drive motor 11a and the left drive motor 11b, respectively. The right drive motor 11a and the left drive motor 11b are driven by the right driver 15a and the left driver 15b. The control device 16 includes an orientation sensor 18, right front obstacle sensors 17a1 and 17a2, center front obstacle sensors 17b1 and 17b2, left front obstacle sensors 17c1 and 17c2, right wall detection sensor 23a, left wall detection sensor 23b, and rear right The right driver 15a and the left driver 15b are controlled according to the detection results of the wall detection sensor 26a, the rear left wall detection sensor 26b, the right distance sensor 14a, and the left distance sensor 14b.
[0016]
In addition, rotatable cleaning brushes 25 a to 25 c are disposed at the rear of the cleaning robot 10. Water spray ports (not shown) are provided in front of the cleaning brushes 25a to 25c, and the cleaning liquid is discharged. A squeegee 24 for sucking sewage is provided at the rear of the cleaning brushes 25a to 25c.
[0017]
FIG. 1 shows the control mechanism of the cleaning robot 10 in more detail. The control unit 16 includes interfaces 19a to 19c, a main controller 20, a counter 21, and an A / D converter 22. 2 and 3, right front obstacle sensors 17a1 and 17a2 are provided on the front right side of the cleaning robot 10, and center front obstacle sensors 17b1 and 17b2 are provided at the front center and left front obstacle. Object sensors 17c1 and 17c2 are provided on the front left side of the cleaning robot 10. The detection distance is as long as 300 to 2500 mm for the sensors 17a1, 17b1 and 17c1, and as short as less than 300mm for the sensors 17a2, 17b2 and 17c2. When these sensors detect an obstacle, the detection signal is input to the interface 19a.
[0018]
The azimuth sensor 18 detects the running azimuth of the cleaning robot 10 with respect to the reference azimuth using, for example, a gyro, and inputs an azimuth detection signal to the interface 19b.
[0019]
The interface 19a receives signals output from the sensors 17a1 to 17c1 and 17a2 to 17c2, performs necessary processing such as amplification, and supplies the processed signal to the main controller 20. The interface 19b is supplied with a signal from the direction sensor 18 to perform amplification or the like, and supplies the amplified signal to the main controller 20.
[0020]
When the right wall detection sensor 23a and the left wall detection sensor 23b and the rear right wall detection sensor 26a and the rear left wall detection sensor 26b detect the distance to the wall and output an analog signal, they are input to the A / D converter 22. Is done. The A / D converter 22 converts this analog signal into a digital signal and outputs it to the main controller 20.
[0021]
Information related to the travel distance of the cleaning robot 10 is also input to the main controller 20. The right distance sensor 14a detects the rotation of the rotation shaft of the right drive motor 11a with an encoder or the like, and the left distance sensor 14b detects the rotation of the rotation shaft of the left drive motor 11b with an encoder or the like and inputs it to the counter 21. . The counter 21 calculates the travel distance between the right wheel 12a and the left wheel 12b from the number of rotations within a predetermined time, and outputs it to the main controller 20.
[0022]
The main controller 20 outputs a control signal to the interface 19c based on information given from the interfaces 19a and 19b, the A / D converter 22, and the counter 21. The interface 19c amplifies this control signal and gives it to the right driver 15a and the left driver 15b. The right driver 15a and the left driver 15b control the operations of the right drive motor 11a and the left drive motor 11b based on this control signal.
[0023]
Next, an operation procedure when the cleaning robot avoids an obstacle by the control method according to the present embodiment will be described with reference to a flowchart. First, FIG. 9 shows a procedure for avoiding an obstacle while traveling along a wall. In step 102, it is determined whether the front obstacle sensors 17 a 2 to 17 c 2 having a short detection distance have detected an obstacle at a close position within 300 mm ahead of the cleaning robot 10. If an obstacle is detected, the process proceeds to step 202 in the flowchart of FIG. If no obstacle is detected, it is determined in step 104 whether the vehicle is traveling along the right wall or the left wall. If the vehicle is traveling along the right wall, in step 106, it is determined whether either the right front obstacle sensor 17a1 or the center front obstacle sensor 17b1 having a long detection distance has detected an obstacle. If the vehicle is traveling along the left wall, in step 108, it is determined whether one of the left front obstacle sensor 17c1 and the center front obstacle sensor 17b1 having a long detection distance has detected an obstacle. When not detected, the routine proceeds to step 124 through step 122, and the normal traveling along the wall is continued. In step 126, it is determined whether or not the vehicle has traveled the set distance. When the vehicle has traveled, travel is stopped as step 128. If the traveling has not been completed yet, the process returns to step 102.
[0024]
When an obstacle is detected in step 106 or 108, the process proceeds to step 110, and the target traveling direction of the cleaning robot 10 is compared with the current traveling direction detected by the direction sensor 18.
[0025]
In step 112, it is determined whether or not the direction is away from the wall. If the direction is away from the wall, the process proceeds to step 118, and the process proceeds slowly. If the direction is closer, the process proceeds to step 114. In step 114, it is determined whether or not the deviation between the target travel direction and the current travel direction is within 2 degrees. Change from 150mm to 300mm. If the deviation in the traveling direction exceeds 2 degrees in step 114, the process proceeds to step 116 and is slowed down. Here, that the deviation between the target traveling direction and the current traveling direction is within 2 degrees means that it is in the hatched region in FIG. 12 (a) or (b). If it is in this area, the routine proceeds to step 118, and if it is outside this area, the routine proceeds to step 116 as exceeding 2 degrees.
[0026]
The process proceeds to step 124 and travels along the wall, and it is determined whether or not the vehicle has traveled the set distance in step 126 described above.
[0027]
In step 102, it is determined whether or not the sensors 17a2 to 17c2 having a short detection distance have detected an obstacle within 300 mm. If detected, the process proceeds to step 202 in FIG. In step 202, the traveling of the cleaning robot 10 is decelerated and stopped. In step 204, a spin turn is performed at an angle of 2 degrees away from the obstacle. Here, the operation procedure when performing the spin turn twice will be described later.
[0028]
In step 206, it is determined whether or not the sensors 17a2 to 17c2 having a short detection distance have detected an obstacle within 300 mm. In step 208, it is determined whether an obstacle has been detected. If detected, the process proceeds to step 210. In step 210, a normal obstacle avoidance operation is performed. Normally, an in-situ spin turn is performed 90 degrees. If no obstacle is detected in step 208, the process proceeds to step 122 to cancel slowing down, and in step 124, traveling along the wall is resumed.
[0029]
FIG. 11 shows the operation procedure of the twice spin turn. In step 302, the rotation of the right drive motor 11a and the left drive motor 11b is decelerated and then stopped. In step 304, it is determined whether the target traveling direction of the cleaning robot 10 is 0 degrees or 180 degrees. When it is 0 degree, it transfers to step 306 and it is judged whether it is driving | running | working along the left wall or driving | running | working along a right wall. In the case of traveling along the left wall, the process proceeds to step 308, and a spin turn is performed in the direction of +2 degrees from the current position of 0 degrees as illustrated. In traveling along the right wall, in step 310, a spin turn is performed in the direction of -2 degrees from the position of 0 degrees.
[0030]
If it is determined in step 304 that the target travel direction is 180 degrees, the process proceeds to step 312. In step 312, it is determined whether the travel is along the left wall or the travel along the right wall. In the case of traveling along the left wall, the process proceeds to step 314, and a spin turn is performed from the current position of 180 degrees toward -178 degrees. In traveling along the right wall, a spin turn is made in the direction of +178 degrees from the position of 180 degrees in step 316.
[0031]
As described above, conventionally, when an obstacle is detected in the forward direction, any obstacles have been rotated 90 degrees four times as shown in FIG. there were. On the other hand, according to the present embodiment, two sensors having different detection distances are provided as sensors for detecting obstacles ahead, and when an obstacle is detected in the distance, the distance between the walls is widened and the obstacle is When an object is detected, a spin turn is performed at an angle of 2 degrees, and after that, when an obstacle is still detected, a 90 degree spin turn is performed. Thereby, it is possible not to perform a useless avoidance operation according to the obstacle, and to improve the efficiency of the cleaning work.
[0032]
This embodiment is an example and does not limit the present invention. For example, in this embodiment, the cleaning robot is provided with a distance sensor between the walls to confirm that an obstacle has been avoided, but this is not necessarily required. Further, when an obstacle is detected, slowing is performed in addition to the operation of increasing the distance between the walls or performing the spin turn, but the operation of slowing is not necessarily employed.
[0033]
【The invention's effect】
As described above, the cleaning robot control method of the present invention provides a long detection distance sensor and a short detection sensor as a front obstacle detection sensor, and a wall when the long detection distance sensor detects an obstacle. Depending on the obstacle, the primary avoidance operation is performed to extend the distance until the sensor is detected. Cleaning efficiency can be improved by performing only the necessary avoidance operation.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a control unit of a cleaning robot controlled by a control method according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a configuration of a cleaning robot equipped with the control unit.
FIG. 3 is a transverse sectional view showing a sectional structure of the cleaning robot.
FIG. 4 is an explanatory view showing a detection range of a sensor of the cleaning robot.
FIG. 5 is an explanatory diagram showing the operation of the twice spin turn of the cleaning robot separately for traveling along the right wall and traveling along the left wall.
FIG. 6 is an explanatory view showing a state in which the cleaning robot changes an inter-wall distance to avoid an obstacle.
FIG. 7 is an explanatory view showing a state in which the cleaning robot makes a spin turn twice to avoid an obstacle.
FIG. 8 is an explanatory view showing a state where an obstacle is still detected after the cleaning robot makes a spin turn twice, and an obstacle is avoided by making a further 90 degree spin turn.
FIG. 9 is a flowchart showing a procedure for avoiding an obstacle when traveling along a wall in the control method according to the embodiment of the present invention;
FIG. 10 is a flowchart showing an avoidance procedure when an obstacle is detected at a close position in the control method.
FIG. 11 is a flowchart showing a procedure of a twice spin turn in the control method.
FIG. 12 is an explanatory diagram showing a deviation between the target traveling direction and the traveling direction of the cleaning robot in the control method.
FIG. 13 is an explanatory diagram showing an operation of avoiding an obstacle by a conventional cleaning robot control method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1a Right wall 1b Left wall 10 Cleaning robot 11a Right drive motor 11b Left drive motor 14a Right distance sensor 14b Left distance sensor 15a Right driver 15b Left driver 16 Control part 17a1, 17a2 Right front obstacle sensor 17b1, 17b2 Center front obstacle sensor 17c1, 17c2 Front left obstacle sensor 18 Direction sensor 19a-19c Interface 20 Main controller 21 Counter 22 A / D converter 23a Right wall detection sensor 23b Left wall detection sensor 24 Squeegee 25a-25c Cleaning brush 26a Rear right wall detection sensor 26b Rear left wall detection sensor

Claims (3)

In the control method of the cleaning robot that avoids the obstacle when the cleaning robot is running along the wall,
A first obstacle detection sensor for detecting a front obstacle, a second obstacle detection sensor for detecting a front obstacle and having a detection distance shorter than that of the first obstacle detection sensor, and a distance to the wall An inter-wall distance detection sensor for measuring the cleaning robot,
Running to keep the distance to the wall at the first distance;
When the first obstacle detection sensor detects an obstacle, a primary avoidance operation is performed in which the distance to the wall detected by the inter-wall distance detection sensor is maintained at a second distance that is farther than the first distance. Steps to do,
After performing the primary avoidance operation, when the second obstacle detection sensor detects an obstacle, stopping the cleaning robot and performing a secondary avoidance operation of performing a spin turn at a predetermined angle;
After performing the primary or the secondary avoidance operation, when no obstacle is detected in front, making sure that you avoid the obstacle by the rear wall detection sensor, to the wall the distance the first A step to keep the distance running,
A cleaning robot control method comprising:   The spin turn in the secondary avoidance operation includes a first spin turn performed at a first angle, and the second obstacle detection sensor after detecting the obstacle after performing the first spin turn. The cleaning robot control method according to claim 1, further comprising: a second spin turn performed at a second angle larger than the first angle. In the control method of the cleaning robot that avoids the obstacle when the cleaning robot is running along the wall,
A first obstacle detection sensor for detecting a front obstacle, a second obstacle detection sensor for detecting a front obstacle and having a detection distance shorter than that of the first obstacle detection sensor, and a distance to the wall The cleaning robot is provided with a wall-to-wall distance detection sensor for measuring the direction and a direction sensor for detecting the traveling direction,
A target travel direction and a first wall distance are set for the cleaning robot, the travel direction detected by the direction sensor maintains the target travel direction, and the distance to the wall detected by the inter-wall distance detection sensor is Running the cleaning robot to maintain the first wall-to-wall distance;
In the case where the first obstacle detection sensor detects an obstacle, the traveling direction detected by the azimuth sensor is deviated closer to the wall than the target traveling direction, and the deviation angle is predetermined. A setting change so as to maintain a second wall-to-wall distance larger than the first wall-to-wall distance,
In the case where the first obstacle detection sensor detects an obstacle, the traveling direction detected by the azimuth sensor is deviated closer to the wall than the target traveling direction, and the deviation angle is When the angle is larger than a predetermined approach angle, the cleaning robot stops traveling when the second obstacle detection sensor detects an obstacle, and the first angle spin-turn is performed in a direction in which the distance to the wall increases. A second angle spin turn greater than the first angle when the second obstacle detection sensor further detects an obstacle; and
A cleaning robot control method comprising:

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