Method and system for the automatic orientation and control of a robot

• US 4,119,900 A
• Filed: 06/16/1976
• Issued: 10/10/1978
• Est. Priority Date: 12/21/1973
• Status: Expired due to Term

• Current Assignee: Mitec-Moderne Industrietechnik GmbH
• Original Assignee: Ito-Patent AG
• Inventors: Kremnitz, Walter
• Primary Examiner(s): Schaefer, Robert K.
• Assistant Examiner(s): Indyk, Eugene S.
• Application Number:
  US05/696,525
• Time in Patent Office: 846 Days
• Field of Search: 235/150.2, 180/79.1, 180/98, 318/580, 318/587, 318/570, 318/574
• US Class Current: 701/23
• CPC Class Codes: G05B 13/047 the criterion being a time optimal performance criterion
• CPC Class Codes: G05D 1/0225 involving docking at a fixed facility, e.g. base station or loading bay parking aids B62D15/027
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0238 using obstacle or wall sensors G05D1/0246 and G05D1/0289 take precedence; lidar systems designed for anti-collision purposes G01S17/93
• 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 1/027 comprising intertial navigation means, e.g. azimuth detector inertial navigation G01C21/16; inertial navigation combined with non-inertial navigation instruments G01C21/165

Abstract

The present method and system for the automatic orientation and control of a robot in a space or on a surface to be worked by the robot, for example an area to be vacuum-cleaned or a lawn to be mowed, employs a plurality of distance measuring devices, which continuously and repeatedly measure distances from the robot to points or small surface areas defining the surface to be worked. Electro-optical distance measuring devices are effective in a far range. Electro-acoustical distance measuring devices are effective in a close range. Electro and/or mechanical means are effective in a contact range. The distance measuring devices continuously ascertain scalar values which by means of data processing are transformed into digital control signals for the drive means and for the tools carried by the robot, whereby the robot plans its own driving and working strategies as the result of said continuous distance measurements. The drive means include wheels which constitute simultaneously digitally controllable drive motors for the robot. The wheels are tiltable about vertical axes for steering the robot.

Claims

1. A method for automatically orienting and controlling a robot system in a space for performing work on a defined surface in said space as a result of said orientation, said robot system travelling on said surface, comprising measuring scalar values on all sides of the system representing said surface or space, supplying said scalar values to data processing means including mathematical models and performing mathematical transformations to produce characteristic data for said surface or space which characteristic data geometrically define said surface or space, to provide a basis for said orienting, processing said characteristic data with the aid of a mathematical optimization model to form operation instructions for said robot system, said operation instructions comprising a sequence of steps for moving and working, and supplying said operation instructions to said robot system, said scalar values being ascertained predominantly during the orientation and/or working.

2. The method according to claim 1, comprising employing a plurality of different type measuring methods for measuring distance between the robot system and points in a far range, in a close range and in a contact range, and arranging said measuring methods in an order of preference or rank.

3. The method according to claim 2, wherein said points comprise relatively small surfaces.

4. The method according to claim 2, comprising measuring in said far range by electro-optical means, said measuring in said far range being followed by a data reduction.

5. The method according to claim 2, comprising measuring in said close range by any one of the following means:

electro-optical means, electro-acoustic means, electrical means, and mechanical means, said measuring in said close range being followed by a data reduction.

6. The method according to claim 2, comprising measuring distance in a binary manner in said contact range by any one of the following means:

mechanical means and electrical means, said binary distance measuring in said contact range being followed by a data reduction.

7. The method according to claim 2, comprising assigning an execution priority to the distance measuring means which measure the smallest distance in said close range.

8. The method according to claim 1, providing an active redundancy including different systems, and partially as well as globally (non-local checking) checking results of said orienting by means of said active redundancy whereby reliability is assured and contradictions are eliminated.

9. The method according to claim 1, further comprising producing an error correction value within a narrow tolerance range for the control of the movement of the robot system, by correlating said scalar values representing an instantaneous position of said robot system, with characteristic space data or with abstracted characteristic space data.

10. The method according to claim 1, further comprising taking first measurements by electro-optical means, taking second combined relative distance and relative angle measurements and correlating said first and second measurements by means of relative coordinates, whereby a non-equal system redundancy is achieved.

11. The method according to claim 1, comprising measuring distance values and converting said distance values into coordinate values by means of transformation.

12. The method according to claim 11, comprising computing said coordinate values in accordance with an orientation planning or orientation strategy as characteristic coordinates and storing said characteristic coordinates in an orientation memory.

13. The method according to claim 11, comprising checking and fixing a coordinate origin for said characteristic coordinates in a space coordinate system by means of an orientation computer, said orientation computer also correlating an instantaneous robot system position and said space coordinate system to each other, and wherein said orientation computer examines and corrects the directly measured coordinates by means of said orientation planning or orientation strategy.

14. The method according to claim 12, comprising storing a current coordinate in said orientation memory in addition to said characteristic coordinates, said current coordinate providing information regarding the instantaneous position of the robot system and the working progress, whereby an orientation coordinate may be used as a working or machining coordinate.

15. The method according to claim 12, wherein a computer performs the driving and working planning or strategies by using the data stored in said orientation memory, said computer computing respective trajectories for the robot system by employing additional data, and wherein said computer corrects said trajectories in response to steering information included in said additional data.

16. The method according to claim 1, wherein an orientation computer causes and controls the continuous orientation of the robot system during the moving and working of the robot system.

17. The method according to claim 1, comprising directly driving said robot system by digitally controllable drive means, and digitally controlling said drive means.

18. The method according to claim 17, comprising steering the robot system by means of said drive means.

19. The method according to claim 17, comprising converting relative trajectory coordinates into digital instructions for said drive means and supplying said digital instructions to said drive means, preferably through power amplifier means.

20. The method according to claim 17, comprising employing steering angles (ε

), which are defined as the angle between a main axis of the robot system and an instantaneous position of a drive axis of the robot system, and a relative angular deviation as well as a relative trajectory for the checking and correction of the trajectory.

21. The method according to claim 1, comprising employing a coordinate computer and an orientation computer and assigning the lowest priority to the coordinate computer and the highest priority to the orientation computer.

22. The method according to claim 1, comprising using in addition to the robot system having a given operational range, satellite robot means having an operational range outside of said given operational range, and controlling said satellite robot means by said robot system.

23. The method according to claim 22, comprising controlling said satellite robot means by central computer means.

24. A robot system including work performing means for working a defined surface comprising:

(a) first means (E1) including distance measuring means, data reduction means and adapter means, second means (E2) including computer means operatively connected to said first means, third means (E3) including memory means, fourth means (E4) including further computer means, said third and fourth means being operatively connected to said second means for cooperation therewith;

(b) fifth means (E5) including additional computer means operatively connected to the first, second, third and fourth means for complex cooperation therewith, sixth means (E6) including control means and data processing means operatively connected to said fifth means, seventh means (E7) including electronic power means and electronic control means operatively connected to said fifth means;

(c) eighth means (E8) including drive means and respective position indicator means operatively connected to said fifth means for supplying angular steering data to said fifth means;

(d) ninth means (E9) operatively connected to the said first through eighth means including self-checking means for continuously checking the operational status of the system, and self-charging means operatively connected to said self-checking means, said ninth means further including means for an operator responsive overriding remote control operation, and

(e) a plurality of battery means and power supply means operatively connected to said work performing means.

25. The system according to claim 24, wherein said robot system has a main axis and wherein said distance measuring means comprise an electro-optical distance measuring device (13) having at least one input-output means (11,12) arranged on each side of the robot system (10), said input-output means (11, 12) being arranged in at least one plane and at a fixed angle relative to a said main axis of the robot system.

26. The system according to claim 25, wherein said input-output means (11, 12) comprises respective lens means each having a lens center, both lens centers having the same coordinates.

27. The system according to claim 26, further comprising a lens system (15) in said electro-optical distance measuring device, light shield means arranged for keeping false light out of said lens system and cleaning means arranged for cleaning said lens system.

28. The system according to claim 25, wherein said input-output means (11, 12) of the electro-optical distance measuring device (13) comprise respective input-output lens means and rotating disk means (16) supporting said input-output lens means, said input-output lens means being arranged on said rotating disk means with a fixed angle (α

,β

) relative to each other.

29. The system according to claim 28, wherein said input lens means and said output lens means are arranged with a fixed angle (α

,β

) therebetween, said system including means operatively associated with said input lens means and said output lens means for sequentially bringing said lens means into an operative position relative to said one distance measuring device.

30. The system according to claim 25, further comprising a lens system (15) in said electro-optical distance measuring device, means operatively associated with said lens system (15) for variably adjusting said lens system to different beam width or beam aperture angles (δ

), whereby a sharp beam focussing is employed for a scalar distance measuring and whereby the beam width (δ

) is widened for recognizing obstacles in an intermediate or close distance measuring range.

31. The system according to claim 25, wherein said electro-optical distance measuring device emits a measuring beam having a sharply focussed beam width corresponding to a beam width angle (δ

) which is substantially zero, said system further comprising an optical distance measuring means emitting a measuring beam having a widened beam width angle.

32. The system according to claim 25, further comprising electro-acoustical distance measuring means (17) arranged around the system in such a manner that said acoustical distance measuring means cover in one or more planes the respective complete coordinate field in a close range.

33. The system according to claim 25, comprising electro-acoustical transmitter means (19) and electro-acoustical receiver means (20) arranged along the outer areas of said system preferably at its four corners (18) close to the ground, said electro-acoustical means (19), 20) providing a system redundancy, if desired.

34. The system according to claim 25, further comprising partial and autonomous drive means which are employed for driving and steering in accordance with rank or preference considerations.

35. The system according to claim 34, wherein said drive means (21) comprise drive motors (23, 24) which simultaneously constitute drive wheels for said system.

36. The system according to claim 35, wherein each of said drive means (21) comprises two digitally controllable motors, preferably reluctance motors, constituting a double wheel, a rigid drive axis, means supporting said wheel for rotation about said rigid drive axis and further means supporting said wheel for turning about a substantially vertical axis.

37. The system according to claim 35, further comprising means connecting said rigid drive axis to said substantially vertical axis for turning about said substantially vertical axis, and means operatively associated with said substantially vertical axis for arresting the latter in certain positions.

38. The system according to claim 34, wherein said drive means (22) comprise a digitally controllable drive motor (29) and means supporting said drive motor at one end thereof for rotation about a substantially horizontal axis, and for turning about a substantially vertical axis, said system further comprising means operatively connected for arresting said drive motor (29) against said turning.

39. The system according to claim 24, further comprising power checking means as part of said self-checking means for continuously checking the operational status of said battery means and said power supply means, and means responsive to said power checking means for automatically replenishing expended power.