Service robot for the automatic suction of dust from floor surfaces

• US 20010004719A1
• Filed: 01/31/2001
• Published: 06/21/2001
• Est. Priority Date: 07/31/1998
• Status: Active Grant

• Current Assignee: Technische Fachhochschule Berlin (TFH)
• Original Assignee: Volker Sommer
• Inventors: Sommer, Volker
• Granted Patent: US 6,370,453 B2
• Time in Patent Office: Days
• US Class Current: 701/23
• CPC Class Codes: A47L 11/12 with reciprocating or oscillating tools
• CPC Class Codes: A47L 11/4011 Regulation of the cleaning machine by electric means; Control systems and remote control systems therefor
• CPC Class Codes: A47L 11/4038 Disk shaped surface treating tools
• CPC Class Codes: A47L 11/4044 Vacuuming or pick-up tools; Squeegees
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: A47L 5/30 with driven dust-loosening tools, e.g. rotating brushes
• CPC Class Codes: G05D 1/0219 ensuring the processing of the whole working surface
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0255 using acoustic signals, e.g. ultra-sonic singals sonar systems designed for anti-collision purposes G01S15/93
• CPC Class Codes: G05D 1/0274 using mapping information stored in a memory device navigation using map-matching G01C21/30
• CPC Class Codes: G05D 2201/0215 Vacuum cleaner

Abstract

The present invention is used for the complete and fully automatic examination of floor surfaces of all kind as well as for a particularly efficient suction of dust therefrom since the lower areas, the edges and the recessed can be detected. In each case, the robot is controlled so as to explore the adjacent area and to detect the potential obstacles using special sensors before storing them in a data field. The displacement towards a new location is then carried out using the stored data until the whole accessible surface has been covered. One of the main constituent members of the robot consists of an extensible arm that rests on the robot and on which contact and range sensors are arranged. When the robot is used as an automatic vacuum cleaner, an air flow is forced into the robot arm and the -cleaning effect can further be enhanced by providing one or more Circular rotary brushes at the front end of the arm. This invention can essentially be used for domestic or industrial Cleaning purposed with a view to replace traditional vacuum cleaners.

Claims

1. Method of automatic controlling a self-moving device, especially a vacuum cleaner, with range-, respectively contact-sensors, wherein a closer area around the device is individually determined and scanned, e. g. by a movable arm, and wherein possible new positions at the borders of the closer area are stored and the device is then moved to a respective new position until no position can be selected anymore;

at this, the determination of the closer area and the selection of the position is realised mainly on the basis of the information of the surroundings, which is stored in a data field and updated in each step, at this, to determine the respective next position, an optimising out of all positions, which have been stored and can be approached by the device, is performed by calculating and comparing for each of these positions certain evaluation parameters, like distances or areas in the reach of a possible new position, which have not yet been scanned, and by selecting the position with the best evaluation result.

3. Method as claimed in

claim 1

, wherein after the detection of an obstacle by a sensor, the exact position of the obstacle is determined under consideration of the scannig direction.

4. Method as claimed in

claim 1

, wherein after the scanning of the closer area, new positions are stored only where no obstacles have been detected and also where no areas border, which have already been scanned before from a previous position of the device.

5. Method as claimed in

claim 1

, wherein when scanning again an area already marked in the data field, every state of this area is updated according to the new sensor data.

6. Method as claimed in

claim 1

, wherein when selecting a new position for the device, only positions, which in the data field are not marked as already scanned, are taken into consideration.

7. Method as claimed in

claim 1

, wherein when storing new positions, different priorities are assigned to these positions, and wherein when selecting a new position for the device, only such positions are considered, whose priorities are not inferior to that of a position already preliminarily selected in the current step.

8. Method as claimed in

claim 1

, wherein when selecting a new position, only such positions are taken into consideration, which are located within a certain partial area, and wherein this partial area will be modified during the process, if within the current partial area no new position can be selected.

9. Method as claimed in

claim 1

, wherein when selecting a new position, the distance and/or the direction between a possible new position and the respective current position of the device is taken into consideration.

10. Method as claimed in

claim 1

, wherein when selecting a new position, the covered distance since the storage of a position is taken into consideration.

11. Method as claimed in

claim 1

, wherein when selecting a new position for the device, it is guaranteed by evaluation of the data field, that the new position can be reached by the device on a direct route, allowing only areas to be traversed, which have already been scanned and which are not marked as an obstacle.

12. Method as claimed in

claim 1

, wherein after the selection of a new position, by evaluating of the data field, the shortest route to the new position within the already scanned area under circumvention of obstacles is determined, and wherein the device is moved along this route.

13. Method as claimed in

claim 1

, wherein the device can be set back to any previous position and wherein in setting back the device over several previous positions, certain positions in between can be skipped, if the evaluation of the data field reveals, that the device does not need to traverse areas which are marked as an obstacle while moving.

14. Method as claimed in

claim 1

, wherein , if an unexpected obstacle blocks the movement of the device, the device will detect the contours of the obstacle by scanning it with its sensors.

15. Method as claimed in

claim 1

, wherein after approaching a new position, the new closer area is determined by evaluating the data field, so that only a small overlap with already scanned neighbouring areas occurs.

16. Method as claimed in

claim 1

, wherein the movable arm is used to clean the floor surface at the same time as the planning is performed.

18. Method as claimed in

claim 1

, wherein the scanning is realised by means of the movable arm so that not yet scanned areas are covered first by the front end of the arm.

19. Method as claimed in

claim 1

, wherein the scanning is realised by means of the movable arm whose front end is guided along the detected obstacle at the smallest possible range.

21. Method as claimed in

claim 1

, wherein the scanning by means of the movable arm in the closer area around the device is selected in form of the sector of a circle.

22. Method as claimed in

claim 1

, wherein the scanning is realised by repeated turns of the device to the left and the right with increased length of the movable arm at each turn.

23. Method as claimed in

claim 1

, wherein the scanning is realised by repeated turns of the device to the left and the right with increased length of the movable arm at each turn with the repeated scanning of already detected obstacles being prevented by shortening the arm in the range of those angles where an obstacle has already been detected.

25. Method as claimed in

claim 16

, wherein by evaluating the information in the data field, the cleaning of the floor surface is performed only in those areas, which are marked as not yet cleaned in the data field.

26. Method as claimed in

claim 1

, wherein the suction engine is only turned on when vacuuming the closer areas and not during the movement of the device towards a new position.

2. Method of automatic controlling a self-moving device, especially a vacuum cleaner, with range-, respectively contact-sensors, wherein a closer area in form of a sector of a circle around the device is scanned by a movable arm, and wherein the device then is moved to a new position and the process is repeated in a loop;

at this the scanning of the closer area is realised, starting with the retracted state of the arm, by repeated turns to the left and the right with an increased length of the arm at each turn, until the given maximum arm length is reached and the arm is then, following a last turn, retracted again.

17. Method as claimed in

claim 2

, wherein the movable arm is used to clean the floor surface at the same time as the scanning is performed.

20. Method as claimed in

claim 2

, wherein the scanning is realised by means of the movable arm whose front end is guided along the detected obstacle at the smallest possible range.

24. Method as claimed in

claim 2

, wherein the scanning is realised by repeated turns of the device to the left and the right with increased length of the movable arm at each turn with the repeated scanning of already detected obstacles being prevented by shortening the arm in the range of those angles where an obstacle has already been detected.

27. Method as claimed in

claim 2

, wherein the suction engine is only turned on when vacuuming the closer areas and not during the movement of the device towards a new position.

28. Device, especially vacuum cleaner, with propelled wheels and steering wheels respectively propelling wheels which can be steered (8) and sensors (13 to 16) and an extensible arm (4) with a head (11) positioned at its front end, comprising, apart from two propelled wheels (8), the use of the head (11) as a third support, which rests on supporting elements like rollers, balls, wheels or bristles.

31. Device, as claimed in

claim 28

, comprising the arm (4) constructed as a telescope arm.

34. Device, as claimed in

claim 28

, comprising the possible variation of the resting-pressure of the head (11) by shifting of weight.

29. Device, especially vacuum cleaner, with propelled wheels and steering wheels respectively propelling wheels which can be steered (8)and sensors (13 to 16) and an extensible arm (4) with a head (11) positioned at its front end, comprising at least one propelled circular brush (12) positioned at the head.

32. Device, as claimed in

claim 29

, comprising the arm (4) constructed as a telescope arm.

35. Device, as claimed in

claim 29

, comprising the arm (4) constructed as a telescope arm, which at its rear end is mounted rotating around a horizontal axis respectively vertically flexible.

37. Device, as claimed in

claim 29

, comprising one or several brushes (12), driven, using a movable shaft (6), by a motor (9), which is positioned on the base of the device(1).

38. Device, as claimed in

claim 29

, comprising at least one brush (12) with bristles (21) which are adjusted diagonally towards the inner part of the brush and which is surrounded by a circle of soft bristles (22) which are adjusted diagonally towards the outer part of the brush.

30. Device, especially vacuum cleaner, with propelled wheels and steering wheels respectively propelling wheels which can be steered (8) and sensors and an extensible arm (4) with a head (11) positioned at its front end, comprising a contact sensor (14) positioned at the head, with which obstacles for the movement of the arm (4) are detected, and a step sensor (15) as well as a height sensor (13) positioned at the head which are used to detect such obstacles which indeed do not block the arm (4), but the movement of the device.

33. Device, as claimed in

claim 30

, comprising the arm (4) constructed as a telescope arm.

36. Device, as claimed in

claim 30

, comprising the arm (4) constructed as a telescope arm, which at its rear end is mounted rotating around a horizontal axis respectively vertically flexible.

39. Device, as claimed in

claim 30

, comprising the contact sensor (14) constructed in form of two electrical conductors positioned within a short distance to each other around the head (11) of the arm (4), from which the outer conductor (20) is pressed elastically against the inner conductor (19) when touching an obstacle, thus closing an electrical circuit.

40. Device, as claimed in

claim 30

, comprising a height sensor (13), applying ultrasonic or electromagnetic waves, to measure the clear height above the head (11).

41. Device, as claimed in

claim 30

, comprising a step sensor (15), in form of a mechanical push button or contact-free, to detect steps in the floor surface.