IP Library Granted Patent US 11,668,076
Granted Patent B2
US 11,668,076 · App. 16/677,308 · Granted Jun 6, 2023

Method and apparatus for controlling excavator to excavate

Inventors: Xinjing Cheng (Beijing, CN); Ruigang Yang (Beijing, CN); Yajue Yang (Beijing, CN); Feixiang Lu (Beijing, CN); Hao Xu (Beijing, CN)
Assignee: Beijing Baidu Netcom Science and Technology Co., Ltd.
E02F9/262E02F9/265G06T3/0031G06T7/593G06T2207/10012
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 11,668,076
App. No.
16/677,308
Granted
Jun 6, 2023
Kind
B2
Abstract

Embodiments of the present disclosure relate to a method and apparatus for controlling an excavator to excavate. The method includes: acquiring a two-dimensional image of a material pile; generating a three-dimensional model of the material pile based on the two-dimensional image; analyzing the three-dimensional model to determine a target excavating point and a target excavating trajectory of the material pile; and controlling an excavator to excavate a material at the target excavating point along the target excavating trajectory.

Claims (51)

1. A method for controlling an excavator to excavate, comprising:

acquiring a two-dimensional image of a material pile;

generating a three-dimensional model of the material pile based on the two-dimensional image;

analyzing the three-dimensional model to determine a target excavating point on the material pile and a target excavating trajectory of a bucket of the excavator, wherein the target excavating trajectory is decomposed into four parts: insertion, dragging, rotation, and lifting, and the target excavating trajectory is characterized by four parameters: an insertion depth of the bucket in the material pile, a dragging length of the bucket in the material pile, a rotation radius of the bucket, and a lifting height of the bucket; and

controlling the excavator to excavate a material at the target excavating point along the target excavating trajectory, comprising:

determining a target angle sequence for a base and an excavating arm of the excavator to excavate the material at the target excavating point along the target excavating trajectory, wherein the target angle sequence includes a sequence of target angles of the base and the excavation arm at sampling points on the target excavating trajectory; and

controlling rotation angles and displacements of the base and the excavating arm based on the target angle sequence.

2. The method according to claim 1 , wherein a side of a body of the excavator is provided with a camera, and the camera captures the two-dimensional image when the body is rotated to unload the material in the bucket.

3. The method according to claim 2 , wherein the camera is a binocular camera, and the two-dimensional image is a binocular image; and

the generating a three-dimensional model of the material pile based on the two-dimensional image comprises:

performing image matching on the binocular image to obtain a parallax image of the binocular image;

generating a depth image of the material pile based on the parallax image; and

performing three-dimensional reconstruction on the depth image to obtain the three-dimensional model of the material pile.

4. The method according to claim 1 , wherein the analyzing the three-dimensional model to determine a target excavating point and a target excavating trajectory of the material pile comprises:

discretizing the three-dimensional model to obtain an excavating point set;

acquiring an excavating trajectory set of an excavating point in the excavating point set;

selecting a candidate excavating point set based on the excavating trajectory set of the excavating point in the excavating point set;

acquiring a material volume of a candidate excavating point in the candidate excavating point set; and

selecting a target excavating point and a target excavating trajectory based on the material volume of the candidate excavating point in the candidate excavating point set.

5. The method according to claim 1 , wherein the controlling an excavator to excavate a material at the target excavating point along the target excavating trajectory further comprises:

acquiring current angles of the base and the excavating arm from a base angle sensor and an excavating arm sensor of the excavator in real time, and performing closed-loop control based on a size and a positive or negative characteristic of a difference between a current target angle in the target angle sequence and the current angles, so that the base and the excavating arm excavate the material at the target excavating point along the target excavating trajectory.

6. An apparatus for controlling an excavator to excavate, comprising:

at least one processor; and

a memory storing instructions, the instructions when executed by the at least one processor, cause the at least one processor to perform operations, the operations comprising:

acquiring a two-dimensional image of a material pile;

generating a three-dimensional model of the material pile based on the two-dimensional image;

analyzing the three-dimensional model to determine a target excavating point on the material pile and a target excavating trajectory of a bucket of the excavator, wherein the target excavating trajectory is decomposed into four parts: insertion, dragging, rotation, and lifting, and the target excavating trajectory is characterized by four parameters: an insertion depth of the bucket in the material pile, a dragging length of the bucket in the material pile, a rotation radius of the bucket, and a lifting height of the bucket; and

controlling the excavator to excavate a material at the target excavating point along the target excavating trajectory, comprising:

determining a target angle sequence for a base and an excavating arm of the excavator to excavate the material at the target excavating point along the target excavating trajectory, wherein the target angle sequence include a sequence of target angles of the base and the excavation arm at sampling points on the target excavating trajectory; and

controlling rotation angles and displacements of the base and the excavating arm based on the target angle sequence.

7. The apparatus according to claim 6 , wherein a side of a body of the excavator is provided with a camera, and the camera captures the two-dimensional image when the body is rotated to unload the material in the bucket.

8. The apparatus according to claim 7 , wherein the camera is a binocular camera, and the two-dimensional image is a binocular image; and

the generating a three-dimensional model of the material pile based on the two-dimensional image comprises:

performing image matching on the binocular image to obtain a parallax image of the binocular image;

generating a depth image of the material pile based on the parallax image; and

performing three-dimensional reconstruction on the depth image to obtain the three-dimensional model of the material pile.

9. The apparatus according to claim 6 , wherein the analyzing the three-dimensional model to determine a target excavating point and a target excavating trajectory of the material pile comprises:

discretizing the three-dimensional model to obtain an excavating point set;

acquiring an excavating trajectory set of an excavating point in the excavating point set;

selecting a candidate excavating point set based on the excavating trajectory set of the excavating point in the excavating point set;

acquiring a material volume of a candidate excavating point in the candidate excavating point set; and

selecting a target excavating point and a target excavating trajectory based on the material volume of the candidate excavating point in the candidate excavating point set.

10. The apparatus according to claim 6 , wherein the controlling an excavator to excavate a material at the target excavating point along the target excavating trajectory further comprises:

acquiring current angles of the base and the excavating arm from a base angle sensor and an excavating arm sensor of the excavator in real time, and performing closed-loop control based on a size and a positive or negative characteristic of a difference between a current target angle in the target angle sequence and the current angles, so that the base and the excavating arm excavate the material at the target excavating point along the target excavating trajectory.

11. A non-transitory computer readable medium, storing a computer program, wherein the computer program, when executed by a processor, causes the processor to perform operations for controlling an excavator to excavate, the operations comprising:

acquiring a two-dimensional image of a material pile;

generating a three-dimensional model of the material pile based on the two-dimensional image;

analyzing the three-dimensional model to determine a target excavating point on the material pile and a target excavating trajectory of a bucket of the excavator, wherein the target excavating trajectory is decomposed into four parts: insertion, dragging, rotation, and lifting, and the target excavating trajectory is characterized by four parameters: an insertion depth of the bucket in the material pile, a dragging length of the bucket in the material pile, a rotation radius of the bucket, and a lifting height of the bucket; and

controlling the excavator to excavate a material at the target excavating point along the target excavating trajectory, comprising:

determining a target angle sequence for a base and an excavating arm of the excavator to excavate the material at the target excavating point along the target excavating trajectory, wherein the target angle sequence include a sequence of target angles of the base and the excavation arm at sampling points on the target excavating trajectory; and

controlling rotation angles and displacements of the base and the excavating arm based on the target angle sequence.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Aug 19, 2021
From: CHENG, XINJING; YANG, RUIGANG; YANG, YAJUE; LU, FEIXIANG; XU, HAO
To: BEIJING BAIDU NETCOM SCIENCE AND TECHNOLOGY CO., LTD.
Reel/Frame 057235/0666 →
Priority Claims (1)
CN 201910075040.5 · Jan 25, 2019 · national
Continuity (1)
Related Publication 20200240117A1 · Jul 30, 2020