System for detecting failure of an Ackerman-type steering mechanism

Patent metadata

Field	Value
Publication number	US-12017699-B2
Application number	US-202117180321-A
Country	US
Kind code	B2
Filing date	Feb 19, 2021
Priority date	Feb 19, 2021
Publication date	Jun 25, 2024
Grant date	Jun 25, 2024

Abstract

A machine includes a frame, a first steering arm, a second steering arm, a first hydraulic actuator coupled to the frame and the first steering arm, and a second hydraulic actuator coupled to the frame and the second steering arm. A first angle sensor measures a rotational displacement of the first hydraulic actuator relative to the first steering arm. A first link couples the first hydraulic actuator and the first sensor, and isolates movements other than the first rotational displacement. A second angle sensor measures a second rotational displacement of the second hydraulic actuator relative to the second steering arm. A second link couples the second hydraulic actuator and the second sensor, and isolates movements other than the second rotational displacement.

First claim

The invention claimed is:

1. A machine, comprising:
a first steering arm coupled to a first wheel of the machine;
a second steering arm coupled to a second wheel of the machine;
a first cylinder extending between the first steering arm and a frame of the machine, actuation of the first cylinder causing first rotation of the first cylinder relative to the frame about a first rotational axis;
a second cylinder extending between the second steering arm and the frame, actuation of the second cylinder causing second rotation of the second cylinder relative to the frame about a second rotational axis;
a first angle sensor configured to sense a first angular displacement corresponding to the first rotation; and
a second angle sensor configured to sense a second angular displacement corresponding to the second rotation.

2. The machine of claim 1 , further comprising a first isolating mechanism coupled to the first cylinder and configured to rotate in response to the actuation of the first cylinder, rotation of the first isolating mechanism being sensed by the first angle sensor as the first angular displacement.

3. The machine of claim 2 , wherein:
the actuation of the first cylinder results in a first movement of the first cylinder other than about the first rotational axis; and
the first isolating mechanism isolates the first rotation of the first cylinder from the first movement of the first cylinder.

4. The machine of claim 3 , wherein the first isolating mechanism comprises a first toggle link including a first portion coupled to the first angle sensor and a second portion coupled to the first cylinder, the first portion being movable relative to the second portion to isolate the first rotation of the first cylinder from the first movement of the first cylinder.

5. The machine of claim 4 , further comprising a first arm coupled to the first angle sensor, the first portion being coupled to the first angle sensor via the first arm, wherein the first arm pivots about the first rotational axis and the first angle sensor is configured to measure the pivot of the first arm.

6. The machine of claim 2 , wherein:
the first cylinder extends along a first longitudinal axis; and
the first isolating mechanism couples to the first cylinder at a position along the first longitudinal axis.

7. The machine of claim 1 , further comprising:
one or more processors; and
one or more non-transitory computer-readable media storing instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising:
receiving, from the first angle sensor, first data corresponding to the first angular displacement;
receiving kinematic data associated with a kinematic relationship between the first cylinder and the second cylinder;
determining, based at least in part on the first angular displacement and the kinematic data, an expected second angular displacement;
receiving, from the second angle sensor, second data corresponding to the second angular displacement;
determining a difference between the second angular displacement and the expected second angular displacement; and
determining, based at least in part on a comparison of the difference to a threshold difference, whether a steering assembly of the machine is functioning properly.

8. The machine of claim 1 , wherein:
the first angle sensor is disposed vertically above a point of rotation at which the first cylinder couples to the first steering arm; and
the second angle sensor is disposed vertically above a point of rotation at which the second cylinder couples to the second steering arm.

9. The machine of claim 1 , wherein:
the first steering arm includes a first kingpin;
the first cylinder couples to the first steering arm via a first pin;
a first axis is disposed through a center of rotation associated with the first kingpin and a center of rotation associated with the first pin;
the first cylinder extends along a first longitudinal axis;
the first angular displacement is measured between the first axis and the first longitudinal axis;
the second steering arm includes a second kingpin;
the second cylinder couples to the second steering arm via a second pin;
a second axis is disposed through a center of rotation associated with the second kingpin and a center of rotation associated with the second pin;
the second cylinder extends along a second longitudinal axis; and
the second angular displacement is measured between the second axis and the second longitudinal axis.

10. A steering assembly, comprising:
a frame;
a first steering arm;
a second steering arm;
a first hydraulic actuator coupled to the frame and to the first steering arm, wherein actuation of the first hydraulic actuator causes the first steering arm to pivot relative to the frame and relative to the first steering arm;
a second hydraulic actuator coupled to the frame and to the second steering arm, wherein actuation of the second hydraulic actuator causes the second steering arm to pivot relative to the frame and relative to the second steering arm;
a first angle sensor disposed to measure a first rotational displacement of the first hydraulic actuator relative to the first steering arm;
a first link coupled at a first end to the first hydraulic actuator and coupled at a second end to the first angle sensor, the first end of the first link being moveable relative to the second end of the first link to isolate movements other than the first rotational displacement;
a second angle sensor disposed to measure a second rotational displacement of the second hydraulic actuator relative to the second steering arm; and
a second link coupled at a third end to the second hydraulic actuator and coupled at a fourth end to the second angle sensor, the third end of the second link being moveable relative to the fourth end of the second link to isolate movements other than the second rotational displacement.

11. The steering assembly of claim 10 , wherein:
the first hydraulic actuator extends along a first longitudinal axis;
the second hydraulic actuator extends along a second longitudinal axis;
the first link couples to the first hydraulic actuator at a point along the first longitudinal axis; and
the second link couples to the second hydraulic actuator at a point along the second longitudinal axis.

12. The steering assembly of claim 10 , further comprising:
a first arm coupling the first angle sensor to the first link; and
a second arm coupling the second angle sensor to the second link.

13. The steering assembly of claim 10 , wherein:
the first link includes a first portion having the first end and a second portion having the second end, the first portion and the second portion being pivotably coupled together; and
the second link includes a third portion having the third end and a fourth portion having the fourth end, the third portion and the fourth portion being pivotably coupled together.

14. The steering assembly of claim 10 , further comprising:
a first bracket disposing the first angle sensor above a top surface of the first steering arm; and
a second bracket disposing the second angle sensor above a top surface of the second steering arm.

15. A machine comprising:
a frame;
a first steering arm coupled to a first wheel of the machine;
a second steering arm coupled to a second wheel of the machine;
a first actuator coupled to a first side of the frame and the first steering arm;
a second actuator coupled to a second side of the frame and the second steering arm;
a first sensor configured to sense a f

Assignees

• Caterpillar Inc

Inventors

• Krone John James
• Sergison Daniel Peter
• Mate Edward William
• Peterson Jeremy T
• Duffer Bradly Glen
• Marquette Matthew Stephen

Classifications

• B62D7/16

  Arrangement of linkage connections (pivots per se F16C) · CPC title

• B62D5/12

  Piston and cylinder · CPC title

• B62D15/021 Primary

  Determination of steering angle · CPC title

• B62D7/166

  substantially perpendicular, e.g. between tie-rod and steering knuckle · CPC title

• B62D7/06

  for individually-pivoted wheels, e.g. on king-pins · CPC title