JPH05224745A - Mobile work robot - Google Patents

Abstract

PURPOSE:To surely detect the level difference in the moving direction of a mobile robot and to ensure the safe movement of the robot which can automatically sweep or clean the floor surface, etc. CONSTITUTION:A mobile work robot is provided with the right and left drive wheels 121, and 12R which drive a main body 11, the drive motors 13L and 13R, a direction measuring device 30 which measures the direction of the body 11, a travel controller 32 which controls the motors 13L and 13R to control the travel of the body 11, a work device which performs a sweeping job, etc., and the level difference detecting means 34 which are set at the front of a follower wheel 14 and the right and left sides of the body 11 respectively. Thus the level differences can be detected in all moving directions of the body 11 when the level differences are detected at the front, right and left sides of the body 11. Furthermore the detecting reliability is improved since the detection is carried out with no contact. Therefore the wheels 12 and 14 never fall at the level difference points as long as the body 11 is stopped when a level difference is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile work robot, such as an automatic floor cleaner, an automatic floor finishing device, etc., for automatically performing work.

[0002]

2. Description of the Related Art In recent years, various mobile work robots have been developed for carrying out work such as automatic floor cleaning by adding a running drive device, sensors, and running control means to working equipment.
For example, a self-propelled cleaner has a suction nozzle, a brush, etc. at the bottom of the main body as a cleaning function, and a traveling means as a moving function.

Since these mobile work robots are automatically moved, they cannot move reliably when they come to a place with a step such as stairs unless they have a means for safely moving even if there is a step. Is. As the step detecting means, conventionally, there are many mechanical means, for example, a means for detecting the displacement of the floor contact mechanism with a limit switch is used.

[0004]

However, in the above-mentioned conventional mobile work robot, since the step detecting means is of a mechanical type, the volume occupied by the step detecting means becomes large, and the places and the number of places that can be installed are limited. Is done.
Also, in terms of performance, there is a problem in reliability such as reliability. In other words, the mobile work robot main body may fall on a step such as a staircase, and the fall may not only damage the main body but also damage surrounding objects or harm the human body.

The present invention is intended to solve the problem of such a conventional configuration, and provides a mobile work robot capable of surely detecting a step in the moving direction and performing safe movement. The purpose is to

[0006]

In order to achieve the above object, the present invention comprises a drive means for moving a main body by independently driving two drive wheels, and a directional follower wheel installed at a front portion of the main body. A mobile work robot having a step detecting means for detecting a step at three points on the front and left and right sides, a travel control means for controlling the drive means to control the travel of the main body, and a work means for performing work such as cleaning. To do.

[0007]

According to the present invention, the step detecting means is provided at the front portion of the driven wheel and the left and right side portions of the front portion of the main body so that the step in all moving directions of the main body can be surely detected and the safe movement can be achieved. It works.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The overall construction of a mobile work robot according to an embodiment of the present invention will be described below with reference to FIGS. Reference numeral 11 denotes a mobile work robot main body (hereinafter simply referred to as a main body), 1
Drive wheels 2L and 12R are provided on the left and right rear sides of the main body 11, and are driven independently by the drive motors 13L and 13R. Reference numeral 14 is a follower wheel rotatably attached to the front of the main body 11. As described above, the drive wheels 12L and 12R, the drive motor 1
The 3L and 13R and the driven wheel 14 constitute a drive means for moving the main body 11. Reference numeral 15 denotes a movable body provided so as to project around the main body 11, and detects this when the main body 11 hits a wall or the like. Reference numeral 16 is a buffer member attached to the movable body 15. Reference numeral 17 denotes an attachment portion attached to the main body 11 so that the movable body 15 can be moved back and forth and right and left. Reference numeral 18 is a cushioning member at the rear of the main body 11.
The reference numeral 19 designates a brush that has been planted around the rotary plate 20 so that the movable body
A motor 21 provided on the rotary shaft 5 is driven to rotate inward of the main body 11 in parallel with the floor surface to sweep dust on the floor surface. 22 is an electric blower, 23 is a dust collecting chamber, 24.
Reference numeral 25 is a filter provided in the dust collection chamber 23. A floor nozzle 26 is provided in the center of the bottom of the main body 11, and is connected to the dust collecting chamber 23 via a connection pipe 27. Brush 19
Motor 21, electric blower 22, dust collection chamber 23, filter 2
4.25 constitutes the cleaning means. Reference numeral 32 is a travel control means for controlling the travel of the main body 11 by controlling the drive motors 13L and 13R. Reference numeral 34 denotes a step detecting means, which is composed of a light emitting element and a light receiving element that receives reflected light from the floor surface. Therefore, the step detecting means 34 is lightweight and small, and can detect the step without contacting the floor surface. In this embodiment, the step detecting means 34 is attached to the movable body 15 so as to emit light vertically downward.

The positional relationship between the driven wheel 14 and the step detecting means 34 will now be described with reference to FIG. In the present embodiment, since the step detecting means 34 is small and lightweight, that is, there is a degree of freedom in selecting the installation location, the step detecting means 3 are provided at three locations near the outer periphery of the main body 11 in front of the driven wheel 14 and on the left and right sides.
4 is provided. The broken line indicates a boundary line where the step detecting means 34 can detect a step. The grounding point of the driven wheel 14 is on the rear side of the main body with respect to the broken line.

Next, the operation of this embodiment will be described. FIG. 4 shows a detection situation when a step appears during actual traveling. FIG. 4A shows a case where a step C is detected forward while the main body 11 is moving forward. At this time, the follower wheel 14
Before the step reaches the step C, the step detecting means 34 provided in the front part of the main body can reach the area of the step C and detect it.

FIG. 4B shows a case where a step C is detected on the right side while steering to the right. When a step is detected on the left side while steering to the left, it is the same as the case of this (b) except for the difference between the left and right, and therefore the description is omitted.
Here, the steering system of the present embodiment will be described with reference to the case of FIG. Rather than steer the drive wheels 12 toward the target direction, the drive wheels 12 remain in the frontal direction of the main body 11 and the main body 11 is steered by giving a speed difference to the left and right drive wheels 12. There is something.
That is, when a speed difference is applied to the left and right drive wheels 12, the movement trajectory of the main body 11 draws an arc. In this way, the main body 11 can be bent in any direction. In the case of FIG. 4B, when the step C is approaching, the step detecting means 34 provided at the front portion of the main body has not reached the area of the step C yet. However, the step detecting means 34 provided on the side of the main body has already detected the step C. That is, by providing the step detecting means 34 also on the side portion, it is possible to detect the step on the side with a margin before the drive wheel 12 reaches this position.

The traveling control of the present embodiment is not premised on the backward movement. Therefore, as described above, if the steps between the front and the left and right sides can be detected, the steps in all moving directions of the main body 11 can be detected. Moreover, since this detection can be performed without contact, it is reliable and highly reliable. If the driving means of the main body 11 is stopped at the time when the step is detected, the driven wheel 14 and the drive wheel 12 will not fall to the step.

That is, in this embodiment, the step detection means 34 of a small size, light weight and non-contact type are provided at three positions, namely, the front part of the driven wheel and the left and right side parts of the front part of the main body, so that the step difference of the main body 11 in all moving directions can be obtained. A mobile work robot that can be reliably detected and has a high degree of safety without falling on a step such as stairs can be provided.

It is best if the number of the slave wheels 14 is one as described in this embodiment, but even if there are two or more slave wheels 14, the position of the ground contact point of each slave wheel is as shown in FIG. If it is on the rear side, this embodiment is effective.

Further, when the step detecting means 3 is installed, the light emitting direction of the light emitting element is set to the vertical downward direction, but it may be tilted to the outer side of the main body 11 in order to detect the step more quickly. In this embodiment, the vertical downward direction is
This is because the light applied to the floor surface is surely received, and if the light is applied obliquely, the reflected light may not be received.

[0016]

As described above, according to the present invention, the drive means for moving the main body by independently driving the two drive wheels, and the front and left and right lateral directions of the directional follower wheels installed in the front portion of the main body are measured. As a mobile work robot equipped with a step detecting means for detecting steps at three points, a traveling control means for controlling the drive means to control traveling of the main body, and a working means for performing work such as cleaning, the robot does not fall on the step. It is possible to realize a highly safe device.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a mobile work robot according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the mobile work robot.

FIG. 3 is an explanatory view showing a positional relationship between a follower wheel of the mobile work robot and a step detecting means.

FIG. 4 is an explanatory diagram for explaining a step detection situation during the traveling.

[Explanation of symbols]

 11 main body 12 drive wheel 13 drive motor 14 follower wheel 15 movable body 19 brush 21 motor 22 electric blower 23 dust collection chamber 24 filter 26 floor nozzle 32 travel control means 34 step detection means

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Osamu Eguchi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (72) Hirofumi Inui 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. 72) Inventor Mitsuyasu Ogawa 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] 1. A driving means for moving a main body by independently driving two driving wheels, and a step detection for detecting a step at three positions, front and left and right sides of a followable directional wheel installed at a front portion of the main body. A mobile work robot comprising: means, a travel control means that controls the drive means to control the travel of the main body, and a work means that performs work such as cleaning.