Obstacle detection for a robotic working tool

• US 10,031,527 B2
• Filed: 02/03/2014
• Issued: 07/24/2018
• Est. Priority Date: 02/03/2014
• Status: Active Grant

• Current Assignee: Husqvarna AB (HUSQVARNA)
• Original Assignee: Husqvarna AB (HUSQVARNA)
• Inventors: Bjorn, Jonathan
• Primary Examiner(s): Jen, Ian
• Application Number:
  US15/116,238
• Publication Number:
  US 20170168499A1
• Time in Patent Office: 1,632 Days
• CPC Class Codes: A01D 34/008 for automated or remotely controlled operation
• CPC Class Codes: A01D 34/08 hand-guided by a walking operator
• CPC Class Codes: G01D 5/145 influenced by the relative movement between the Hall device and magnetic fields see G01R33/06
• CPC Class Codes: G05D 1/0033 by having the operator tracking the vehicle either by direct line of sight or via one or more cameras located remotely from the vehicle
• CPC Class Codes: G05D 1/0038 by providing the operator with simple or augmented images from one or more cameras located onboard the vehicle, e.g. tele-operation images analyzed by a computer and used for automatic navigation G05D1/0246
• CPC Class Codes: G05D 1/0227 using mechanical sensing means, e.g. for sensing treated area
• CPC Class Codes: G05D 1/0265 using buried wires

Abstract

A robotic work tool system (200) comprising a robotic work tool (100) comprising a collision detection sensor (190), said collision detection sensor (190) comprising a first sensor element (191) and a plurality of second sensor elements (192), wherein said first sensor element (191) is movably arranged with respect to said plurality of second sensor elements (192), wherein said robotic work tool (100) is configured to detect that said first sensor element (191) is proximate a peripheral second sensor element (192) and in response thereto determine that a collision has been detected, and detect that said first sensor element (191) is not proximate any peripheral second sensor element (192) and in response thereto determine that a lift has been detected.

Claims

1. A robotic work tool system comprising a robotic work tool comprising a collision detection sensor, said collision detection sensor comprising a first sensor element and a plurality of second sensor elements, wherein said first sensor element is movably arranged with respect to said plurality of second sensor elements, wherein said robotic work tool is configured to

detect that said first sensor element is proximate a peripheral second sensor element and in response thereto determine that a collision has been detected, and

detect that said first sensor element is not proximate any second sensor element and in response thereto determine that a lift has been detected.

2. The robotic work tool system according to claim 1, wherein the robotic work tool further comprises a body and a chassis, wherein said body is attached to said chassis via elastic fittings.

3. The robotic work tool system according to claim 2, wherein said body is movable both in a direction in a same plane as a direction of movement of the robotic work tool as well as in a direction perpendicular to the same plane.

4. The robotic work tool system according to claim 1, wherein the first sensor element is a magnet and wherein at least one of the plurality of second sensor elements is a hall sensor.

5. The robotic work tool system according to claim 2, wherein said first sensor element is arranged in said body and said plurality of second sensor elements is arranged in said chassis.

6. The robotic work tool system according to claim 4, wherein said first sensor element is arranged in said chassis and said plurality of second sensor elements is arranged in said body.

7. The robotic work tool system according to claim 1, wherein the robotic work tool comprises only one collision detection sensor.

8. The robotic work tool system according to claim 1, wherein said robotic work tool is further configured to detect at which side the collision occurred, by determining which of the peripheral second sensor elements that is proximate the first sensor element.

9. The robotic work tool system according to claim 8, wherein said robotic work tool is further configured to detect that the first sensor element is proximate more than one peripheral second sensor element and in response thereto, determine a collision side based on the combination of peripheral second sensor elements being proximate the first sensor element.

10. The robotic work tool system according to claim 1, wherein said plurality of second sensor elements are arranged so that there is one central second sensor element and at least one peripheral second sensor element, which are arranged at a substantially equal distance to the central second sensor element.

11. The robotic work tool system according to claim 1, wherein the robotic work tool is a robotic lawnmower.

12. The robotic work tool system according to claim 1, wherein the robotic work tool is a farming equipment, a vacuum cleaner, a floor cleaner, a street sweeper, a snow removal tool, a golf ball retriever robot, a cleaner robot, a leaves blower robot, a leaves collector robot, snow thrower robot or a mine clearance robot.

13. A method for use in a robotic work tool system comprising a robotic work tool comprising a collision detection sensor, said collision detection sensor comprising a first sensor element and a plurality of second sensor elements, wherein said first sensor element is movably arranged with respect to said plurality of second sensor elements, wherein said method comprises

detecting that said first sensor element is proximate a peripheral second sensor element and in response thereto determining that a collision has been detected, and

detecting that said first sensor element is not proximate any second sensor element and in response thereto determining that a lift has been detected.