Work machine with operator presence detection strategy

• US 20070203630A1
• Filed: 02/24/2006
• Published: 08/30/2007
• Est. Priority Date: 02/24/2006
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Vitale, Andrew, Funke, Brian
• Granted Patent: US 7,899,597 B2
• Time in Patent Office: Days
• US Class Current: 701/50
• CPC Class Codes: B60K 28/04 responsive to presence or absence of the driver, e.g. to weight or lack thereof
• CPC Class Codes: B60W 2540/103 Accelerator thresholds, e.g. kickdown
• CPC Class Codes: B60Y 2200/411 Bulldozers, Graders
• CPC Class Codes: E02F 9/2095 Control of electric, electro-mechanical or mechanical equipment not otherwise provided for, e.g. ventilators, electro-driven fans control of hydraulic driven equipment E02F9/22
• CPC Class Codes: E02F 9/24 Safety devices , e.g. for preventing overload E02F9/226 takes precedence
• CPC Class Codes: E02F 9/26 Indicating devices E02F5/145 takes precedence

Abstract

A work machine uses an operator presence detection strategy to enable or disable the work machine. A plurality of sensors provide independent indications of operator presence. These sensors may include a seat sensor, an inching pedal sensor, a transmission output speed sensor and a conveyance gear sensor. The work machine is enabled if at least one sensor indicates the presence of an operator; however, the work machine is disabled if none of the sensors indicate an operator.

Claims

1. A method of operating a work machine, comprising the steps of:

sensing indicators of operator presence in the work machine, which includes sensing a seat sensor, a transmission output speed sensor and a conveyance gear sensor;

enabling the work machine if at least one of the indicators indicates that an operator is present in the work machine; and

disabling the work machine if none of the indicators indicates that an operator is present in the work machine.

2. The method of claim 1 wherein the sensing step includes sensing an inching pedal sensor.

3. The method of claim 2 including the steps of:

indicating the presence of an operator if a sensed transmission output speed is non-zero;

indicating the presence of an operator if a sensed conveyance gear is not neutral;

indicating the presence of an operator if the seat sensor is in an operator-in-seat position; and

indicating the presence of an operator if a sensed inching pedal position is greater than a predetermined threshold.

4. The method of claim 3 wherein the predetermined threshold is a ninety percent position.

5. The method of claim 4 wherein the disabling step includes the steps of:

locking out work machine implements; and

engaging a parking brake of the work machine.

6. The method of claim 5 wherein the work machine implements includes a grader.

7. A work machine comprising:

a work machine body that includes an operator station;

an electronic controller connected to the work machine body;

a transmission output speed sensor in communication with the electronic controller;

a conveyance gear sensor in communication with the electronic controller;

a seat sensor in communication with the electronic controller; and

the electronic controller includes an operator presence algorithm operable to enable the work machine based on any one of a seat sensor indication, a transmission output speed sensor indication, and a conveyance gear sensor indication, and being operable to disable the work machine based on a combination of all of the seat sensor indication, the transmission output speed sensor indication and the conveyance gear sensor indication.

8. The work machine of claim 7 including an inching pedal sensor in communication with the electronic controller;

and

the operator presence algorithm is also operable to enable the work machine based on an inching pedal sensor indication alone, and being operable to disable the work machine based on the inching pedal sensor indication in combination with the seat sensor indication, the transmission output speed sensor indication and the conveyance gear sensor indication.

9. The work machine of claim 8 wherein the work machine body is a motor grader body;

and

the at least one implement includes a grader.

10. The work machine of claim 9 including a parking brake in communication with the electronic controller;

the operator presence algorithm is operable to engage the parking brake as part of disabling the work machine.

11. The work machine of claim 10 wherein the operator presence algorithm is operable to enable the work machine if the seat sensor indication is operator-in-seat, or if the transmission output speed sensor indication is non-zero, or if the conveyance gear sensor indication is not neutral, or if the inching pedal sensor indication is pressed;

and

the operator presence sensor algorithm is operable to disable the work machine if the seat sensor indication is operator-not-in-seat, and the transmission output speed sensor indication is zero, and the conveyance gear sensor indication is neutral, and the inching pedal sensor indication is not-pressed.

12. An electronic controller for a work machine comprising:

an operator presence algorithm operable to enable control communication between a work machine implement and an operator control if at least one of a plurality of sensors has an indication that satisfies a respective predetermined criterion, and being operable to disable control communication between the work machine implement and the operator control if a combination of all of the plurality of sensors have indications that fail to satisfy the respective predetermined criteria.

13. The electronic controller of claim 12 includes means for receiving the plurality of sensor indications, which include a seat sensor indication, a transmission output speed sensor indication and a conveyance gear sensor indication.

14. The electronic controller of claim 13 wherein the plurality of sensor indications includes an inching pedal sensor indication.

15. The electronic controller of claim 13 wherein the operator presence algorithm is operable to engage a parking brake if the combination of all of the plurality of sensors have indications that fail to satisfy the respective predetermined criteria.