METHOD AND SYSTEM FOR CONTROLLING A VEHICLE FOR LOADING OR DIGGING MATERIAL

• US 20080234902A1
• Filed: 07/24/2007
• Published: 09/25/2008
• Est. Priority Date: 03/20/2007
• Status: Active Grant

• Current Assignee: Deere & Company
• Original Assignee: Deere & Company
• Inventors: Sahlin, Mark Peter, Anderson, Eric Richard, Johnson, David August, Cherney, Mark John
• Granted Patent: US 8,036,797 B2
• Time in Patent Office: Days
• US Class Current: 701/50
• CPC Class Codes: E02F 3/422 Drive systems for bucket-arms, front-end loaders, dumpers or the like
• CPC Class Codes: E02F 9/2029 Controlling the position of implements in function of its load, e.g. modifying the attitude of implements in accordance to vehicle speed control for hydraulic or pneumatic drives E02F9/2203, E02F9/2221 and E02F9/2253 take precedence

Abstract

A method and system for controlling a vehicle comprises a torque detector for detecting a first torque level and a second torque level applied to at least one wheel of the vehicle. The first torque level is associated with a lower boom position of a boom. An accelerometer detects an acceleration level of the boom during or after raising of the boom. A first hydraulic cylinder is capable of raising a boom from the lower boom position to raise an available torque from the first torque level. A second hydraulic cylinder is adapted to upwardly rotate or curl a bucket associated with the vehicle if the detected acceleration level of the boom is less than a minimum level during an attempt to raise the boom.

Claims

1. A method for controlling a vehicle for a digging operation, the method comprising:

detecting a first torque level of torque applied to at least one wheel of the vehicle, the first torque level associated with a lower boom position of a boom associated with the vehicle;

raising the boom from the lower boom position associated with the vehicle to raise an available torque from the first torque level if the first torque level exceeds a first torque threshold;

detecting an acceleration level of the boom during or after raising the boom; and

upwardly rotating or curling a bucket associated with the vehicle if the detected acceleration level of the boom is less than a minimum level during an attempt to raise the boom.

2. The method according to claim 1 further comprising:

establishing the first torque threshold based on a first maximum level of torque associated with the vehicle in the lower boom position, the lower boom position having a boom height less than a critical height; and

establishing the minimum level of acceleration based a stalling state of the upward movement of the boom.

3. The method according to claim 1 wherein the raising of the boom comprises:

increasing an initial rate of upward boom movement associated with the boom to a higher rate of boom movement proportionally to an increase in the detected first torque level during a time interval.

4. The method according to claim 3 wherein increasing the initial rate of upward boom movement comprises generating a signal or data command to increase an opening of a valve associated with a hydraulic cylinder operably connected to the boom.

5. The method according to claim 1 further comprising:

determining that a pile of material is considered potentially present in a work area if a vehicle speed relative to the ground decreases below a speed threshold and if the first torque level exceeds a minimum threshold.

6. The method according to claim 1 wherein detecting first torque level of torque comprises estimating the first torque level based on a shaft rotational speed of at least one of a transmission, a torque converter, a drive train, a motor, and an engine.

7. The method according to claim 1 wherein the raising of the boom comprises increasing an initial rate of upward boom movement associated with the boom to a higher rate of boom movement proportionally to a decrease in the detected ground speed of the vehicle during a time interval.

8. The method according to claim 1 wherein the upward rotation or the curling of the bucket comprises increasing an initial rate of upward bucket rotation associated with the bucket to a higher rate of bucket rotation proportionally to a decrease in the detected ground speed during a time interval.

9. The method according to claim 1 wherein the wheel comprises a cogwheel associated with a track of linked members or a belt, and wherein the vehicle comprises a tracked vehicle or crawler.

10. A system for controlling a vehicle, the system comprising:

a torque detector for detecting a first torque level and a second torque level of torque applied to at least one wheel of the vehicle, the first torque level associated with a lower boom position of a boom associated with the vehicle;

an accelerometer for detecting an acceleration level of the boom during or after raising the boom;

a first hydraulic cylinder for raising the boom from the lower boom position to raise an available torque from the first torque level;

a second hydraulic cylinder for upwardly rotating a bucket associated with the vehicle; and

a controller for sending first control data or a first control signal for controlling the first hydraulic cylinder to raise the boom if the first torque level exceeds a first torque threshold and for sending second control data or a second control signal to upwardly rotate the bucket if the detected acceleration level of the boom is less than a minimum level during an attempt to raise the boom.

11. The system according to claim 10 wherein the first torque threshold is based on a first maximum level of torque associated with the vehicle in the lower boom position and;

the lower boom position having a boom height less than a critical height.

12. The system according to claim 10 wherein the controller is arranged to increase an initial rate of upward boom movement associated with the boom to a higher rate of boom movement proportionally to an increase in the detected first torque level during a time interval.

13. The system according to claim 12 wherein the controller generates the first control signal or first control data to increase an opening of a valve associated with the first hydraulic cylinder.

14. The system according to claim 10 further comprising:

a ground speed sensor associated with the vehicle for measuring a ground speed of the vehicle; and

a pile detector for determining that a pile of material is considered potentially present in a work area if the measured ground speed decreases below a ground speed threshold and if the first torque level exceeds a minimum threshold.

15. The system according to claim 10 wherein the torque detector detects a first torque level based on a shaft rotational speed of at least one of a transmission, a torque converter, a drive train, a motor, and an engine.

16. The system according to claim 10 wherein the controller is arranged to increase an initial rate of upward boom movement associated with the boom to a higher rate of boom movement proportionally to a decrease in the detected ground speed of the vehicle during a time interval.

17. The system according to claim 10 wherein the controller is arranged to increase an initial rate of upward bucket rotation associated with the bucket to a higher rate of bucket rotation proportionally to a decrease in the detected ground speed during a time interval.

18. The system according to claim 10 further comprising:

a plurality of tracks of linked members; and

a plurality of cogwheels as the at least one wheel, the cogwheels engaging the linked members, the vehicle regarded as a tracked vehicle.