Automatic track alignment control kit and method for automated track alignment

Patent metadata

Field	Value
Publication number	US-9696147-B2
Application number	US-201414783850-A
Country	US
Kind code	B2
Filing date	Apr 9, 2014
Priority date	Apr 10, 2013
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

The invention relates to a method for aligning tracks of a roadwork machine, characterized by using a track alignment detection unit that is attached to a first track unit for allowing detection of an orientation of the first track unit, and frame orientation detection means that are attached to the machine frame for allowing detection of an orientation of the machine frame, the method comprising determining an initial orientation of the machine frame, and determining an initial orientation of the first track unit, determining whether a difference between a most recently determined orientation of the machine frame and a most recently determined orientation of the first track unit is within a predefined threshold value, initializing a pivoting of the first track unit, determining a changed orientation of the first track unit after the pivoting, and determining an orientation of the machine frame after the pivoting.

First claim

What is claimed is:

1. A method for aligning tracks of a roadwork machine, the roadwork machine being designed for producing and/or processing a surface layer comprising concrete or asphalt material along a predetermined path, and comprising a machine frame with:
a surface processor for carrying out a material processing step,
a plurality of track units with tracks for moving the roadwork machine along a first axis and actuators for pivoting the track units about a second axis with respect to the machine frame, wherein the second axis is orthogonal to the first axis, and
a machine guidance system for controlling the tracks and the actuators of the track units,
wherein at least one retro-reflector is attached to a first track unit for allowing detection of an orientation of the first track unit, and at least one retro-reflector is attached to the machine frame for allowing detection of an orientation of the machine frame;
the method comprising:
determining an initial orientation of the machine frame,
determining an initial orientation of the first track unit,
determining whether a difference between a most recently determined orientation of the machine frame and a most recently determined orientation of the first track unit is within a predefined threshold value,
initializing a pivoting of the first track unit,
determining a changed orientation of the first track unit after the pivoting, and
determining an orientation of the machine frame after the pivoting.

2. The method according to claim 1 , further comprising:
repeating the following steps until an angular difference between a most recently determined orientation of the machine frame and a most recently determined orientation of the first track unit is within a predefined threshold value:
reiteratively pivoting the first track unit and determining its orientation after the pivoting, until the angular difference is within the predefined threshold value, and
determining an orientation of the machine frame.

3. The method according to claim 1 , wherein
for pivoting the track unit, a correction angle is calculated in a control and evaluation unit, wherein the track unit is pivoted about the correction angle.

4. The method according to claim 1 , wherein the steps
determining an initial orientation of the machine frame, and
determining an initial orientation of the first track unit,
are performed by a user using a geodetic surveying instrument.

5. The method according to claim 1 , wherein the steps
determining a changed orientation of the first track unit after the pivoting, and
determining an orientation of the machine frame after the pivoting,
are performed automatically by means of a geodetic surveying instrument.

6. The method according to claim 1 , wherein
a geodetic surveying instrument is used for determining the orientations, by measuring distance and direction to the at least one retro-reflector that is attached to the first track unit.

7. The method according to claim 1 , wherein
a retro-reflector and an optically perceivable pattern are attached to the first track unit for allowing detection of the orientation of the first track unit; and
determining the orientations is performed by means of a laser tracker having a camera.

8. The method according to claim 1 , wherein:
two retro-reflectors that are fixedly connected to each other in a known distance are attached to the first track unit for allowing detection of the orientation of the first track unit.

9. The method according to claim 3 , wherein:
two retro-reflectors are positioned on the track unit at a known distance from each other, and
calculating the correction angle is based on the most recently determined orientation of the machine frame, the most recently determined orientation of the track unit and the known distance between the two retro-reflectors, in particular wherein the correction angle is calculated by the equation:

α
=

sin
⁡

(

frame
⁢

⁢
orientation

-

track
⁢

⁢
orientation

2

)

·

(

d
2

)

·
2.

10. An Automatic Track Alignment Control Kit for aligning tracks of a roadwork machine, the roadwork machine being designed for producing and/or processing a surface layer comprising concrete or asphalt material along a predetermined path, and comprising a machine frame with
a surface processor for carrying out a material processing step,
a plurality of track units with tracks for moving the roadwork machine along a first axis and actuators for pivoting the track units about a second axis with respect to the machine frame, wherein the second axis is orthogonal to the first axis, and
a machine guidance system for controlling the tracks and the actuators of the track units,
wherein the Automatic Track Alignment Control Kit comprises:
an orientation determining device comprising a laser range finder
at least one retro-reflector for use with the laser range finder, and
a control and evaluation unit,
wherein:
the at least one retro-reflector is designed for being attachable to a first track unit of the roadwork machine,
the orientation determining device is designed for determining an orientation of the first track unit and an orientation of the machine frame, and
the control and evaluation unit is designed for determining an orientation of the first track unit relative to the machine frame and for sending a command to the machine guidance system to pivot the first track unit in order to align the first track unit and the machine frame, wherein the control and evaluation unit is designed for performing the following steps:
initializing a pivoting of the first track unit,
determining the orientation of the first track unit after pivoting,
determining an orientation of the machine frame after pivoting, and
determining whether a difference between a most recently determined orientation of the machine frame and a most recently determined orientation of the first track unit is within a predefined threshold value.

11. The Automatic Track Alignment Control Kit according to claim 10 , further comprising:
at least one retro-reflector being attachable to the machine frame for use with the laser range finder for allowing detection of the orientation of the machine frame.

12. The Automatic Track Alignment Control Kit according to claim 10 , wherein for allowing determining the orientation of the first track unit, the Kit comprises one of:
two retro-reflectors that are fixedly connected to each other in a known distance,
a 6DOF retro-reflector, and
a retro-reflector

Assignees

• Leica Geosystems Ag

Inventors

• Dokter Jeremy
• Bakker Adriaan

Classifications

• E01C19/48

  for laying-down the materials and consolidating them, or finishing the surface {, e.g. slip forms therefor, forming kerbs or gutters in a continuous operation in situ (E01C19/002, E01C23/065 take precedence; devices for guiding or controlling the machines along a predetermined path E01C19/004)} · CPC title

• E01C19/006 Primary

  by laser or ultrasound · CPC title

• G01B11/26 Primary

  for measuring angles or tapers; for testing the alignment of axes · CPC title

• G01C3/00

  Measuring distances in line of sight; Optical rangefinders (tapes, chains or wheels for measuring length G01B3/00; active triangulation systems, i.e. using the transmission and reflection of electromagnetic waves other than radio waves, G01S17/48) · CPC title

• G01C15/002

  Active optical surveying means (optical plumbing G01C15/105) · CPC title