AUTONOMOUS ROBOT

• US 20130274920A1
• Filed: 06/15/2013
• Published: 10/17/2013
• Est. Priority Date: 12/06/2006
• Status: Active Grant

• Current Assignee: Mtd Products Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: F Robotics Acquisitions Ltd. (Stanley Black & Decker, Inc.)
• Inventors: Abramson, Shai, Ikar, Ido
• Granted Patent: US 9,079,303 B2
• Time in Patent Office: Days
• US Class Current: 700/250
• CPC Class Codes: A01D 34/008 for automated or remotely controlled operation
• CPC Class Codes: A01G 25/00 Watering gardens, fields, sports grounds or the like special apparatus or adaptations for fertilising-liquids A01C23/00; nozzles or outlets, spraying apparatus B05B
• CPC Class Codes: A47L 2201/00 Robotic cleaning machines, i.e. with automatic control of the travelling movement or the cleaning operation
• CPC Class Codes: A47L 2201/04 Automatic control of the travelling movement; Automatic obstacle detection
• CPC Class Codes: B25J 9/0003 Home robots, i.e. small robots for domestic use
• 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 1/0265 using buried wires
• CPC Class Codes: H04B 2203/5458 Monitor sensor; Alarm systems
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines
• CPC Class Codes: H04B 3/548 the power on the line being DC arrangements for feeding power H04L12/10; extracting feeding power from signals H04L25/02
• CPC Class Codes: Y10S 901/01 Mobile robot

Abstract

A method for communication between a charging station and a robot, via a pair of power lines coupled between a power supply in the charging station and a battery in the robot. In operation, the power supply is sequentially switched between a first voltage level and a second voltage level in accordance with a predetermined signal pattern. The voltage level on the power lines in the robot is monitored and correlated with a specific command to be executed by the robot.

Claims

1. A method for scanning, by a robot, a work area to be covered by the robot, wherein the robot travels inside the work area in successive paths, each initiated when the robot changes direction, the method comprising:

scanning the work area using a first scanning pattern;

monitoring the length of each of the paths traveled by the robot;

switching from the first scanning mode to a second scanning pattern when an obstacle is encountered on a minimum number of consecutive said paths each having a length between a first threshold distance and a longer, second threshold distance; and

switching back to the first scanning pattern when the length of one of the paths has increased to more than the second threshold distance.

2. The method of claim 1, wherein the first scanning pattern comprises the robot traveling in a random walk pattern, and wherein the second scanning pattern comprises the robot traveling in a pattern comprising alternating pairs of essentially parallel paths, wherein a first one of the paths in each of the alternating pairs is oriented at an angle between approximately 120 and 240 degrees from the angle of the immediately previous one of the paths.

3. The method of claim 1, wherein, if a predetermined number of consecutive paths traveled by the robot are each shorter than the first threshold distance, determining that the robot has reached a corner, in response to which the robot performs a maneuver to exit from the corner.

4. The method of claim 1, wherein the robot changes direction in the first scanning mode and in the second scanning mode when a work area boundary is encountered and when an obstacle is encountered.

5. The method of claim 1, wherein the minimum number of consecutive paths is at least two.

6. A method for maneuvering a robot to extricate a robot from a problem area comprising:

saving the heading of the robot as heading H1, when the robot encounters a first obstacle;

performing an in-place turn in a first direction;

saving the heading of the robot as heading H2, when the robot encounters a second obstacle;

performing a turn in the reverse direction of the first turn substantially toward the bisector of the sector bounded by headings H1 and H2; and

continuing operation with a forward leg to move between the first obstacle and the second obstacle, in a heading whose angular direction is substantially equal to the bisected angle H1-H2.

7. The method of claim 6, wherein the first obstacle and the second obstacle are selected from a combination of obstacles consisting of two solid obstacles, and one solid obstacle and a perimeter boundary wire.

8. A method for maneuvering a robot to extricate a robot from within a problem area bounded partially by an obstacle comprising:

(a) traversing a straight leg until an obstacle is encountered;

(b) performing a turn in a first direction;

(c) continuing a straight leg traverse;

(d) determining whether the robot is still inside the problem area; and

(e) repeating steps (a) and (b) until the robot is no longer inside the problem area.

9. The method of claim 8, wherein the turn has an angular value of between approximately 10 and 30 degrees.

10. The method of claim 8, wherein the step of determining whether the robot is still inside the problem area is performed by observing that a straight leg traversed by the robot is longer than a predetermined value.