Autonomous Mobile Robot

• US 20150271991A1
• Filed: 03/17/2015
• Published: 10/01/2015
• Est. Priority Date: 03/31/2014
• Status: Active Grant

• Current Assignee: iRobot Corporation
• Original Assignee: iRobot Corporation
• Inventors: Balutis, Paul C.
• Granted Patent: US 9,554,508 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A01D 34/008 for automated or remotely controlled operation
• CPC Class Codes: B25J 5/007 mounted on wheels
• CPC Class Codes: G05D 1/0011 associated with a remote control arrangement
• CPC Class Codes: G05D 1/0016 characterised by the operator's input device input arrangements for computing systems in general G06F3/00
• CPC Class Codes: G05D 1/0221 involving a learning process
• CPC Class Codes: G05D 1/028 using a RF signal

Abstract

A robot lawnmower includes a robot body, a drive system, a localizing system, a teach monitor, and a controller in communication with one another. The drive system is configured to maneuver the robot lawnmower over a lawn. The teach monitor determines whether the robot lawnmower is in a teachable state. The controller includes a data processing device and non-transitory memory in communication with the data processing device. The data processing device executes a teach routine when the controller is in a teach mode for tracing a confinement perimeter around the lawn as a human operator pilots the robot lawn mower, when the robot lawnmower is in the teachable state, the teach routine stores global positions determined by the localizing system in the non-transitory memory, and when the robot lawnmower is in the unteachable state, the teach routine issues an indication of the unteachable state.

Claims

1. A robot lawnmower comprising:

a robot body;

a drive system supporting the robot body and configured to maneuver the robot lawnmower over a lawn;

a localizing system configured to determine perimeter positions of the robot lawnmower with respect to an origin;

a teach monitor in communication with the localizing system and configured to determine whether the robot lawnmower is in a teachable state, with the robot lawnmower localized and on traversable terrain, or in an unteachable state; and

a controller in communication with the drive system, the localizing system, and the teach monitor, the controller comprising;

a data processing device; and

non-transitory memory in communication with the data processing device;

wherein the controller is configured to execute a teach routine when the controller is in a teach mode for tracing a confinement perimeter around the lawn as a human operator pilots the robot lawnmower with the robot lawnmower in the teachable state, while the teach routine stores perimeter positions determined by the localizing system in the non-transitory memory.

2. The robot lawnmower of claim 1, further comprising an operator feedback unit in communication with the teach monitor or the controller and configured to emit, in response to determining that the robot lawnmower is in the unteachable state, a human-perceptible unteachable state alert signal.

3. The robot lawnmower of claim 2, wherein the unteachable state alert signal indicates a piloting correction in a pose or a motion of the robot lawnmower calculated to return the robot lawnmower to the teachable state.

4. The robot lawnmower of claim 2, wherein the operator feedback unit is in wireless communication with one or more boundary markers positioned along the perimeter of the lawn.

5. The robot lawnmower of claim 2, wherein the operator feedback unit is in wireless communication with the controller and comprises a user interface configured for remotely piloting the robot lawnmower.

6. The robot lawnmower of claim 1, further comprising a sensor system in communication with the teach monitor, the sensor system comprising at least one of:

an inertial measurement unit responsive to a moment of inertia of the robot lawnmower;

an obstacle sensor responsive to proximity of an obstacle or water along a drive path of the robot lawnmower;

a tilt sensor responsive to tilt of the robot body;

a cliff sensor responsive to a discrete ground elevation change proximate the robot body or a drive element of the drive system;

a drop sensor responsive to a drop of a drive element of the drive system;

an accelerometer responsive to speed of the robot lawnmower across the lawn; and

a confinement sensor responsive to proximity of the robot lawnmower to a boundary marker.

7. The robot lawnmower of claim 6, wherein the teach monitor is configured to determine that the robot lawnmower is in the unteachable state in response to a signal from the sensor system.

8. The robot lawnmower of claim 1, wherein the controller, executing the teach routine, is configured to determine a traveled path of the robot lawnmower based on the stored perimeter positions and whether the traveled path begins and ends proximate the origin.

9. The robot lawnmower of claim 1, wherein the origin comprises coordinates marked by one or more boundary markers positioned in the lawn.

10. The robot lawnmower of claim 9, further comprising a boundary detection scanner disposed on the robot body and configured to perform a scan match on three or more adjacent boundary markers, each of the three or more boundary markers individually identifiable by adjacent scan match data.

11. The robot lawnmower of claim 10, wherein the teach routine determines a travel path of the robot lawnmower by scan matching a current travel path scan with a stored travel path scan.

12. A method of configuring a robotic lawnmowing system for autonomous operation, the method comprising:

receiving, at a data processing device, perimeter positions of a robot lawnmower with respect to an origin;

receiving, at the data processing device, a state of the robot lawnmower indicating whether the robot lawnmower is in a teachable state, with the robot lawnmower localized and on traversable terrain, or in an unteachable state; and

executing, on the data processing device, a teach routine that traces a confinement perimeter around a lawn as a human operator pilots the robot lawnmower, while the teach routine

stores received perimeter positions in non-transitory memory when the robot lawnmower is in the teachable state, and

issues an unteachable state indication when the robot lawnmower is in the unteachable state.

13. The method of claim 12, wherein the unteachable state indication comprises a human-perceptible signal emitted by the robot lawnmower.

14. The method of claim 13, wherein the unteachable state indication indicates a piloting correction in a pose or a motion of the robot lawnmower selected to return the robot lawnmower to the teachable state.

15. The method of claim 12, wherein the origin comprises coordinates marked by one or more boundary markers positioned in the lawn.

16. The method of claim 12, wherein the teach routine, executing on the data processing device, compares a current perimeter position stored in the non-transitory memory to previously stored perimeter positions and determines whether a variance is greater than a threshold variance from a stored travel path.

17. A robotic lawnmower system, comprising:

a localizing system that records each global position of a robot lawnmower with respect to a global origin as a human operator pilots the robot lawnmower to trace a confinement perimeter around a lawn in a manual confinement perimeter teaching mode;

contour memory in which a geometric contour of the confinement perimeter is recorded while the human operator pilots the robot lawnmower for a duration of operation in manual confinement perimeter teaching mode, the geometric contour defining a perimeter that the robot lawnmower is to avoid crossing in an autonomous mode;

a teaching property monitor configured to detect whether or not the robot lawnmower is piloted in a recordable state and on traversable terrain; and

an operator feedback unit in communication with the teaching property monitor and comprising a progress indicator capable of emitting a human-perceptible signal configured to;

(i) alert the human operator to an unrecordable state or untraversable terrain, and

(ii) indicate a piloting correction to return the robot lawnmower to a recordable state or traversable terrain.

18. The robotic lawnmower system of claim 17, wherein the operator feedback unit is mounted on a handle of the robot lawnmower.

19. The robotic lawnmower system of claim 17, wherein the operator feedback unit is in wireless communication with one or more boundary markers positioned along the confinement perimeter and is configured to indicate a piloting correction in response to the robot lawnmower travelling proximate to or beyond the perimeter.

20. The robotic lawnmower system of claim 17, wherein the travel path of the robot lawnmower is localized by determining angle and range of the robot lawnmower to three or more boundary markers.