Calibration system and calibration method for excavator

Patent metadata

Field	Value
Publication number	US-9644346-B2
Application number	US-201414389571-A
Country	US
Kind code	B2
Filing date	May 14, 2014
Priority date	May 14, 2014
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

A calibration system for an excavator includes the excavator having an upper structure swingably attached to a chassis, a working machine having a boom, an arm, and a working tool, and a current position computation unit configured to compute a current position of a working point of the working tool; a calibration device configured to calibrate parameters based on parameters indicating dimensions and rotation angles of the boom, the arm, and the working tool; an external measurement device that measures a position of the working point; and an inclination information detection device that detects inclination information of the excavator in an anteroposterior direction. The calibration device corrects positions of the working point measured by the external measurement device, based on the inclination information of the excavator in the anteroposterior direction, and computes calibrated values of the parameters based on coordinates of the working point at corrected positions.

First claim

The invention claimed is:

1. A calibration system for an excavator, comprising:
the excavator that includes a chassis, an upper structure that is swingably attached to the chassis, a working machine that includes a boom rotatably attached to the upper structure, an arm rotatably attached to the boom, and a working tool rotatably attached to the arm, and a current position computation processor that computes a current position of a working point included in the working tool, based on a plurality of parameters indicating dimensions of the boom, the arm, and the working tool, a rotation angle of the boom with respect to the upper structure, a rotation angle of the arm with respect to the boom, and a rotation angle of the working tool with respect to the arm;
a calibration device including a processor configured to calibrate the parameters;
an external position measurement device that measures a position of the working point; and
an inclination information detector to detect inclination information of the excavator in an anteroposterior direction of a vehicle body, wherein
the processor of the calibration device corrects a plurality of positions of the working point measured by the external position measurement device, based on the inclination information of the excavator in the anteroposterior direction of the vehicle body detected by the inclination information detector, and computes calibrated values of the parameters based on coordinates of the working point at the plurality of corrected positions.

2. The calibration system for an excavator according to claim 1 , wherein the inclination information is a pitch angle of the excavator.

3. The calibration system for an excavator according to claim 1 , wherein the processor of the calibration device corrects the plurality of positions of the working point according to the following equation:

(

x
c

z
c

)

=

(

cos
⁢

⁢

θ
p

-
sin

⁢

⁢

θ
p

sin
⁢

⁢

θ
p

cos
⁢

⁢

θ
p

)

⁢

(

X
c
′

-

X
c

⁢
0

Z
c
′

-

Z
c

⁢
0

)

where:
(Xc′, Zc′) are coordinates of a position of a blade edge of a bucket of the excavator measured by the external position measurement device in earth's gravitational coordinate system X-Z,
(Xc, Zc) are the coordinates of the blade edge at an original position of the working machine in the coordinate system X-Z,
(Xc0, Zc0) are coordinates of a position CP which is an origin of the coordinate system X-Z, and
θp is a pitch angle reflecting rotation of a position of the blade edge in an upward direction around the position CP.

4. A calibration system for an excavator, comprising:
the excavator that includes a chassis, an upper structure that is swingably attached to the chassis, a working machine that includes a boom rotatably attached to the upper structure, an arm rotatably attached to the boom, and a working tool rotatably attached to the arm, an angle detection unit that detects a rotation angle of the boom with respect to the upper structure, a rotation angle of the arm with respect to the boom and a rotation angle of the working tool with respect to the arm, and a current position computation unit that computes a current position of a working point included in the working tool, based on a plurality of parameters indicating dimensions and the rotation angles of the boom, the arm, and the working tool;
a calibration device configured to calibrate the parameters;
an external measurement device that measures a position of the working point; and
an inclination information detection device that detects inclination information of the excavator in an anteroposterior direction of a vehicle body, wherein
the calibration device includes:
an input unit into which working machine position information including at least three positions of the working point different in posture of the working machine measured by the external measurement device, upper structure position information including at least three positions of the working point different in swing angle of the upper structure with respect to the chassis, and inclination information of the excavator in the anteroposterior direction of the vehicle body corresponding to the positions of the working point included in the wo

Assignees

• Komatsu Mfg Co Ltd

Inventors

• Seki Masanobu
• Ichihara Masashi

Classifications

• G01B21/042

  Calibration or calibration artifacts (G01B3/30, G01B9/02072 take precedence) · CPC title

• E02F9/264 Primary

  Sensors and their calibration for indicating the position of the work tool · CPC title

• E02F3/435

  for dipper-arms, backhoes or the like · CPC title

• E02F3/32

  working downwardly and towards the machine, e.g. with backhoes · CPC title

• G01S19/40

  Correcting position, velocity or attitude · CPC title