Load based ground speed control method

Patent metadata

Field	Value
Publication number	US-11533844-B2
Application number	US-202016777931-A
Country	US
Kind code	B2
Filing date	Jan 31, 2020
Priority date	Jan 31, 2020
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

Methods for autonomous operation of harvesters use header drive pump displacement, header speed, harvester ground speed, engine load and engine speed to control and maximize harvester operation under varying conditions such as crop type, crop condition and terrain. Adaptive learning processes within the methods relate the parameters of pump displacement with header speed and engine speed during harvester operation to permit the control system to establish combinations of related control parameters which are used by a control system to control harvester operation.

First claim

What is claimed is:

1. A method for controlling a ground speed of an engine driven harvester comprising a header for cutting crop, said header powered by a hydraulic pump, said method comprising:
establishing a maximum engine load;
establishing a maximum ground speed;
establishing a minimum ground speed;
establishing a desired header speed;
measuring a current ground speed;
measuring a current engine load;
comparing said current engine load with said maximum engine load;
decreasing said current ground speed if said current engine load is greater than said maximum engine load;
measuring a current engine speed;
measuring a current header speed;
establishing a maximum pump displacement;
measuring a current pump displacement;
comparing said current pump displacement with said maximum pump displacement;
decreasing said current ground speed if said current pump displacement is greater than said maximum pump displacement;
comparing said current header speed with said desired header speed;
decreasing said current ground speed if said current header speed is less than said desired header speed;
comparing said current ground speed with said maximum ground speed;
decreasing said current ground speed if said current ground speed is greater than said maximum ground speed; and
increasing said current ground speed if said current ground speed is less than said maximum ground speed.

2. The method according to claim 1 , wherein said comparing said current engine load with said maximum engine load comprises comparing a current output torque of said engine with a maximum available torque at said current engine speed.

3. The method according to claim 1 , wherein said establishing a desired header speed step includes establishing the desired header speed based upon at least one of a type of said crop and a condition of said crop.

4. The method according to claim 1 , wherein said establishing a maximum engine load step comprises selecting a fraction of a maximum available torque for a plurality of engine speeds.

5. The method according to claim 1 , wherein said establishing a maximum pump displacement step includes establishing the maximum pump displacement as a function of said current engine speed and said current header speed.

6. The method according to claim 1 , wherein said measuring a current pump displacement step includes using a parameter selected from a group consisting of a swashplate angle of said pump, a swashplate actuator voltage, a swashplate actuator current and combinations thereof.

7. The method according to claim 1 , further comprising the step of decreasing said current ground speed in a sequence of steps over a time interval when said current engine load is greater than said maximum engine load.

8. The method according to claim 7 , wherein said current ground speed is decreased a same amount for each said step of the sequence of steps.

9. The method according to claim 7 , wherein said current ground speed is decreased in proportion to a difference between said current engine load and said maximum engine load.

10. The method according to claim 1 , further comprising the step of decreasing said current ground speed in a sequence of steps over a time interval when said current pump displacement is greater than said maximum pump displacement.

11. The method according to claim 10 , wherein said current ground speed is decreased a same amount for each said step of the sequence of steps.

12. The method according to claim 10 , wherein said current ground speed is decreased in proportion to a difference between said current pump displacement and said maximum pump displacement.

13. The method according to claim 1 , further comprising the step of decreasing said current ground speed in a sequence of steps over a time interval when said current header speed is less than said desired header speed.

14. The method according to claim 13 , wherein said current ground speed is decreased a same amount for each said step of the sequence of steps.

15. The method according to claim 13 , wherein said current ground speed is decreased in proportion to a difference between said current header speed and said desired header speed.

16. The method according to claim 1 , further comprising the step of decreasing said current ground speed in a sequence of steps over a time interval when said current ground speed is greater than said maximum ground speed.

17. The method according to claim 16 , wherein said current ground speed is decreased a same amount for each said step of the sequence of steps.

18. The method according to claim 16 , wherein said current ground speed is decreased in proportion to a difference between said current ground speed and said maximum ground speed.

19. The method according to claim 1 , further comprising the step of increasing said current ground speed in a sequence of steps over a time interval when said current ground speed is less than said maximum ground speed.

20. The method according to claim 19 , wherein said current ground speed is increased a same amount for each said step of the sequence of steps.

21. The method according to claim 19 , wherein said current ground speed is increased in proportion to a difference between said current ground speed and said maximum ground speed.

22. The method according to claim 1 , further comprising:
establishing a correspondence table relating said maximum pump displacement with a header speed and an engine speed;
establishing a range of desired header speeds;
establishing a range of permitted engine speeds; wherein
for each time a desired header speed is achieved within said range of desired header speeds, and, with said current engine speed being within said range of permitted engine speeds, measuring said current pump displacement; and
associating said desired header speed and said current engine speed with said current pump displacement in said correspondence table.

23. The method according to claim 22 , wherein measuring said current pump displacement is effected by measuring a parameter selected from a group consisting of a swashplate angle of said pump, a swashplate actuator voltage, a swashplate actuator current and combinations thereof.

24. The method according to claim 23 , further comprising decreasing said current ground speed when said current pump displacement is greater than said maximum pump displacement associated with said desired header speed and said current engine speed in said correspondence table.

25. A control system for controlling a ground speed of an engine driven harvester comprising a header for cutting crop, said header powered by a hydraulic pump, said control system comprising:
a controller;
a control interface adapted to receive control inputs from an operator and transmit said control inputs to said controller;
an engine speed sensor adapted to generate signals indicative of engine speed and transmit said signals to said controller;
an engine load sensor adapted to generate signals indicative of engine load and transmit said signals to said controller;
a header speed sensor adapted to generate signals indicative of header speed and transmit said signals to said controller;
a pump displacement sensor adapted to generate signals indicative of pump displacement and transmit said signals to said controller;
an engine speed actuator adapted to receive signals from said controller and change said engine speed in re

Assignees

• Cnh Ind America Llc

Inventors

• Pankaj Madhu
• Fackler Robert L

Classifications

• A01D69/03

  fluid · CPC title

• A01D41/1274 Primary

  for drives · CPC title

• G05D1/0223 Primary

  involving speed control of the vehicle (vehicle fittings for automatically controlling, i.e. preventing speed from exceeding an arbitrarily established velocity or maintaining speed at a particular velocity, as selected by the vehicle operator B60K31/00) · CPC title