MOWING BOUNDARY AREA AND GRASS LENGTH RECOGNIZING APPARATUS METHOD OF MOWING ROBOT

• US 20150096276A1
• Filed: 03/20/2014
• Published: 04/09/2015
• Est. Priority Date: 10/07/2013
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: YU, Won Pil, PARK, Jae Hyun, CHOI, Sung Lok
• Granted Patent: US 9,554,507 B2
• Time in Patent Office: Days
• US Class Current: 56/10.2A
• CPC Class Codes: A01D 34/008 for automated or remotely controlled operation

Abstract

Provided is a mowing boundary area recognizing apparatus of a mowing robot. The mowing boundary area recognizing apparatus includes a ground state measurer configured to acquire environment data of a ground based on a grass length on the ground, a determiner configured to determine the grass length on the ground on a basis of the ground environment data to recognize a mowing boundary area, and a controller configured to adjust running of the mowing robot to a mowing area for which mowing is needed.

Claims

1. A mowing boundary area recognizing apparatus of a mowing robot, the mowing boundary area recognizing apparatus comprising:

a ground state measurer configured to acquire environment data of a ground based on a grass length on the ground;

a determiner configured to determine the grass length on the ground on a basis of the ground environment data to recognize a mowing boundary area; and

a controller configured to control running of the mowing robot to a mowing area for which mowing is needed.

2. The mowing boundary area recognizing apparatus of claim 1, wherein,

the ground state measurer comprises a ground slip state measuring unit configured to estimate a friction coefficient of a wheel of the mowing robot on a basis of frictional force of the wheel of the mowing robot, or estimate a degree of slip of the ground on a basis of frequency number of slip occurrence of the ground, and

when the friction coefficient of the wheel of the mowing robot acquired from the ground slip state measuring unit is equal to or less than a certain value, or the frequency number of slip occurrence of the ground is equal to or greater than another certain value, the determiner recognizes the ground as the mowing area.

3. The mowing boundary area recognizing apparatus of claim 2, wherein,

the ground slip state measuring unit comprises a slope measuring unit configured to, in a ground having a slope, correct the friction coefficient of the wheel of the mowing robot and the frequency number of slip occurrence of the ground, in consideration of the slope of the ground, and

the determiner determines the mowing area on a basis of the corrected friction coefficient and frequency number of slip occurrence of the ground according to the slope of the ground.

4. The mowing boundary area recognizing apparatus of claim 1, wherein,

the ground state measurer comprises a running state measuring unit configured to measure number of rotations of the wheel of the mowing robot and an amount of current that is consumed when the wheel is rotating, and compare a running state of the mowing robot by using the measured number of rotations of the wheel of the mowing robot and the measured amount of consumed current, and

the determiner determines, as the mowing area, a ground in which the measured number of rotations of the wheel of the mowing robot and the measured amount of consumed current are equal to or greater than a certain value.

5. The mowing boundary area recognizing apparatus of claim 1, wherein,

the ground state measurer comprises a light reflection intensity measuring unit configured to measure a light reflection intensity of the ground based on a color, a content of water, and a roughness of the ground, and

the determiner determines the ground as the mowing area when the light reflection intensity of the ground acquired from the light reflection intensity measuring unit is equal to or greater than a certain value.

6. The mowing boundary area recognizing apparatus of claim 1, wherein,

the ground state measurer comprises a motor torque measuring unit configured to measure an amount of consumed current and a torque of a motor that drives a mowing blade of the mowing robot, and

the determiner determines the mowing area on a basis of the torque or amount of consumed current of the motor acquired from the motor torque measuring unit.

7. A mowing boundary area recognizing method of a mowing robot, the mowing boundary area recognizing method comprising:

acquiring environment data of a ground based on a grass length on the ground;

determining the grass length on the ground on a basis of the ground environment data to recognize a mowing boundary area; and

adjusting running of the mowing robot to a mowing area for which mowing is needed.

8. The mowing boundary area recognizing method of claim 7, wherein the acquiring of environment data comprises:

estimating a friction coefficient of a wheel of the mowing robot on a basis of frictional force of the wheel of the mowing robot, or estimating a degree of slip of the ground on a basis of frequency number of slip occurrence of the ground; and

recognizing the mowing area on a basis of the estimated friction coefficient of the wheel of the mowing robot or the estimated frequency number of slip occurrence of the ground.

9. The mowing boundary area recognizing method of claim 8, wherein the estimating of a degree of slip comprises, in a ground having a slope, correcting the friction coefficient of the wheel of the mowing robot and the frequency number of slip occurrence of the ground, in consideration of the slope of the ground.

10. The mowing boundary area recognizing method of claim 7, wherein the acquiring of environment data comprises:

measuring number of rotations of the wheel of the mowing robot and an amount of current that is consumed when the wheel is rotating; and

comparing the number of rotations of the wheel of the mowing robot and the amount of consumed current in the ground under a condition of the same power or the same time.

11. The mowing boundary area recognizing method of claim 7, wherein the acquiring of environment data comprises:

measuring a light reflection intensity of the ground based on a color, a content of water, and a roughness of the ground; and

determining the mowing area on a basis of the measured light reflection intensity of the ground.

12. The mowing boundary area recognizing method of claim 7, wherein the acquiring of environment data comprises:

measuring an amount of consumed current and a torque of a motor that drives a mowing blade of the mowing robot; and

comparing the torque and the amount of consumed current of the motor under a condition of the same power or the same time to determine the mowing area.

13. A grass length recognizing method of a mowing robot, the grass length recognizing method comprising:

detecting a distance between the mowing robot and a plant growing on a ground;

when the detected distance is equal to or less than a certain value, determining the plant-growing ground as a mowing-required area; and

running the mowing robot to the mowing-required area.

14. The grass length recognizing method of claim 13, wherein the detecting of a distance comprises recognizing, as a distance between the plant and the mowing robot, an average value of distances between a plurality of the sensors equipped in the mowing robot and the plant to determine a grass length on the ground.

15. A grass length recognizing method of a mowing robot, the grass length recognizing method comprising:

detecting, by a sensor, a plant growing on a ground as an obstacle;

determining the obstacle-detected ground as a mowing area for which mowing work is needed; and

running the mowing robot to the mowing area.

16. The grass length recognizing method of claim 15, wherein the running of the mowing robot comprises determining an obstacle-detected area to control running of the mowing robot according to an arrangement type of the sensor.