Autonomous lawn mower, self-moving device, and method for recognizing obstacle by same

Patent metadata

Field	Value
Publication number	US-11256267-B2
Application number	US-201916287309-A
Country	US
Kind code	B2
Filing date	Feb 27, 2019
Priority date	Aug 31, 2016
Publication date	Feb 22, 2022
Grant date	Feb 22, 2022

Abstract

The present invention relates to a non-contact obstacle-avoiding autonomous lawn mower, including a housing, a moving module, a drive module, and a control module. An ultrasonic sensor assembly is disposed on the housing. The ultrasonic sensor assembly includes at least two ultrasonic sensors, including a first ultrasonic sensor and a second ultrasonic sensor. When a distance between an obstacle detected by the ultrasonic sensor assembly and the autonomous lawn mower is less than a preset distance, the control module controls the autonomous lawn mower to execute a preset obstacle-avoidance measure. Compared with the prior art, the present invention uses an ultrasonic sensor to detect an obstacle and sets a preset distance to prevent the autonomous lawn mower from colliding with the obstacle, thereby implementing non-contact obstacle avoidance of the autonomous lawn mower.

First claim

What is claimed is:

1. An autonomous lawn mower, comprising:
a housing;
a moving module, disposed below the housing, and configured to drive the housing to move;
a drive module, configured to drive the moving module to move;
an ultrasonic sensor assembly configured to recognize an obstacle in a forward movement direction of the autonomous lawn mower is disposed on the housing, the ultrasonic sensor assembly comprises at least two ultrasonic sensors, comprising a first ultrasonic sensor and a second ultrasonic sensor, the first ultrasonic sensor receives and transmits ultrasound in a first transceiver region, the second ultrasonic sensor receives and transmits ultrasound in a second transceiver region, and the first ultrasonic sensor and the second ultrasonic sensor are arranged on the housing and directed toward one another such that the first transceiver region and the second transceiver region overlap partially to form three detection regions, wherein the portion where the first transceiver region and the second transceiver region overlap each other is a third detection region, the portion of the first transceiver region that doesn't overlap with the second transceiver region is a first detection region, the portion of the second transceiver region that doesn't overlap with the first transceiver region is a second detection region; and
wherein when a distance between an obstacle detected by the ultrasonic sensor assembly and the autonomous lawn mower is less than a preset distance, the autonomous lawn mower executes a preset obstacle-avoidance measure to avoid the obstacle.

2. The autonomous lawn mower according to claim 1 , wherein the first ultrasonic sensor has a first axis, the second ultrasonic sensor has a second axis, and the angle between the first axis and the second axis ranges from 60° to 110°.

3. The autonomous lawn mower according to claim 2 , wherein the angle between the first axis and the second axis ranges from 70° to 90°.

4. The autonomous lawn mower according to claim 1 , wherein the first ultrasonic sensor has a first axis, the second ultrasonic sensor has a second axis, the housing has a housing axis, and the angle between the first axis and the housing axis ranges from 10° to 80°, the angle between the second axis and the housing axis ranges from 10° to 80°.

5. The autonomous lawn mower according to claim 4 , wherein the angle between the first axis and the housing axis ranges from 25° to 55°, the angle between the second axis and the housing axis ranges from 25° to 55°.

6. The autonomous lawn mower according to claim 1 , wherein the third detection region at least covers both a part of a first distance-measurement blind area in the first transceiver region and a part of a second distance-measurement blind area in the second transceiver region.

7. The autonomous lawn mower according to claim 1 , wherein an ultrasonic beam pattern for recognizing an obstacle in a forward movement direction of the autonomous lawn mower is noncircular, a tangent plane is formed by an axis perpendicular to the ultrasonic beam pattern to obtain a waveform surface, the waveform surface has a major axis direction and a minor axis direction, the major axis direction is mounted to be basically parallel to a bottom surface of the autonomous lawn mower, and the minor axis direction is mounted to be basically perpendicular to the bottom surface of the autonomous lawn mower.

8. The autonomous lawn mower according to claim 1 , wherein the ultrasonic sensor assembly comprises an ultrasonic sensor configured to transmit and receive ultrasound, a PCB board, and a protection case for fixing the PCB board and the ultrasonic sensor, the ultrasonic sensor has an outward sound-producing surface, the protection case has an end surface, and the sound-producing surface is level with the end surface or is concave relative to the end surface to be disposed in the protection case.

9. The autonomous lawn mower according to claim 1 , wherein the first ultrasonic sensor has a sound beam axis, and the sound beam axis is arranged horizontally.

10. The autonomous lawn mower according to claim 9 , wherein the first transceiver region has a first border line near a front end of the housing, the housing has a neighboring wall adjacent to the first transceiver region, and an upper surface of the neighboring wall is lower than the first border line.

11. The autonomous lawn mower according to claim 1 , wherein the autonomous lawn mower further comprises a crosstalk prevention structure, configured to prevent ultrasound sent by one of the first ultrasonic sensor and the second ultrasonic sensor from being received directly by the other one of the two without being reflected by the obstacle.

12. The autonomous lawn mower according to claim 11 , wherein the crosstalk prevention structure is disposed between the first ultrasonic sensor and the second ultrasonic sensor.

13. The autonomous lawn mower according to claim 11 , wherein the crosstalk prevention structure extends toward a front side of the housing without coming into contact with an axis of an ultrasonic sensor.

14. The autonomous lawn mower according to claim 11 , wherein the crosstalk prevention structure extends toward a front side of the housing without exceeding an intersection of projections of an axis of the first ultrasonic sensor and an axis of the second ultrasonic sensor.

15. The autonomous lawn mower according to claim 11 , wherein the crosstalk prevention structure is located on a front side of a connecting line between a sound wave transmission point of the first ultrasonic sensor and a sound wave transmission point of the second ultrasonic sensor and extends toward a front side of the housing.

16. A self-moving device, comprising:
a housing;
a moving module, disposed below the housing, and configured to drive the housing to move;
a drive module, configured to drive the moving module to move; and
an ultrasonic sensor assembly configured to recognize an obstacle in a forward movement direction of the self-moving device is disposed on the housing, the ultrasonic sensor assembly comprises at least two ultrasonic sensors, comprising a first ultrasonic sensor and a second ultrasonic sensor, the first ultrasonic sensor receives and transmits ultrasound in a first transceiver region, the second ultrasonic sensor receives and transmits ultrasound in a second transceiver region, the first ultrasonic sensor and the second ultrasonic sensor are arranged on the housing and directed toward one another such that the first transceiver region and the second transceiver region overlap partially to form three detection regions, wherein the portion where the first transceiver region and the second transceiver region overlap each other is a third detection region, the portion of the first transceiver region that doesn't overlap with the second transceiver region is a first detection region, the portion of the second transceiver region that doesn't overlap with the first transceiver region is a second detection region, and the moving module moves the self-moving device along a preset path to keep a distance between the housing and the obstacle greater than zero.

17. A self-moving device, comprising:
a housing;
a moving module, disposed below the housing, and configured to drive the housing to move;
a drive module, configured to drive the moving module to move; and
an ultrasonic sensor assembly configured to recognize an obstacle in a forward movement direction of the self-moving device is disposed on the housing, the ultrasonic sensor assembly comprises at least tw

Assignees

• Positec Power Tools Suzhou Co Ltd

Inventors

• Sheng Xiaochu
• Ran Yuanzhong
• Pang Yanjun
• Du Jiang
• Li Xinghong

Classifications

• A01D34/00

  Mowers (combined with apparatus performing additional operations while mowing A01D37/00 - A01D41/00, A01D43/00; convertible to apparatus for purposes other than mowing or capable of performing operations other than mowing A01D42/00); Mowing apparatus of harvesters · CPC title

• A01D2101/00

  Lawn-mowers · CPC title

• A01D75/185

  Avoiding collisions with obstacles · CPC title

• A01D34/008 Primary

  for automated or remotely controlled operation · CPC title

• G01S2015/937

  sensor installation details · CPC title