Grade and payload estimate-based transmission gear selection

Patent metadata

Field	Value
Publication number	US-8954246-B2
Application number	US-201213715106-A
Country	US
Kind code	B2
Filing date	Dec 14, 2012
Priority date	Dec 14, 2012
Publication date	Feb 10, 2015
Grant date	Feb 10, 2015

Abstract

A vehicle includes an automatic transmission and a set of sensor inputs providing values indicating a current operational status of the vehicle pertinent to controlling the automatic transmission. The set of sensor inputs include: engine speed, engine torque, current transmission gear; and vehicle speed. The vehicle includes a programmed processor configured to iteratively and co-dependently generate a vehicle mass parameter value and a grade of incline parameter value. The programmed processor, when generating the vehicle mass parameter value and the grade of incline parameter value, uses a set of parameters including: a propulsive force driving the vehicle; a set of forces acting on the vehicle resisting forward movement, and an observed rate of change of a speed of the vehicle.

First claim

What is claimed is:

1. A vehicle including:
an automatic transmission;
a set of sensor inputs providing values indicating a current operational status of the vehicle and pertinent to controlling the automatic transmission, the set of sensor inputs including:
engine speed;
engine torque;
current transmission gear; and
vehicle speed; and

a programmed controller configured by computer-executable instructions to iteratively and co-dependently generate both a vehicle mass parameter value and a grade of incline parameter value, the programmed controller using a set of parameters including:
a propulsive force driving the vehicle;
a set of forces acting on the vehicle resisting forward movement, and
an observed rate of change of a speed of the vehicle,

wherein co-dependently generating both the vehicle mass parameter value and the grade of incline parameter value comprises using a previously generated vehicle mass parameter value to generate a current incline parameter value, and using a previously generated incline parameter value to generate a current vehicle mass parameter.

2. The vehicle of claim 1 wherein a mass calculator of the programmed controller carries out generating the vehicle mass parameter value, and wherein the programmed controller is further configured to include a reset/hold logic functionality that selectively issues a command to the mass calculator to reset a current value for the vehicle mass parameter value during a period of mechanical instability.

3. The vehicle of claim 2 wherein the period of mechanical instability arises from a turning operation of the vehicle.

4. The vehicle of claim 2 wherein the period of mechanical instability arises from a dumping operation by the vehicle.

5. The vehicle of claim 1 wherein the set of forces acting on the vehicle resisting forward movement include an actuable implement/tool force.

6. The vehicle of claim 1 wherein the set of forces acting on the vehicle resisting forward movement include a force of inertia arising from a transmission, and wherein a value for the force of inertia is determined at least in part by a currently selected operating gear of the vehicle.

7. The vehicle of claim 1 wherein the set of forces acting on the vehicle resisting forward movement include a traveled surface-dependent force.

8. The vehicle of claim 1 wherein the set of forces acting on the vehicle resisting forward movement include a speed-dependent air resistance force.

9. The vehicle of claim 1 wherein the programmed controller is further configured to select a shift control schedule based upon the generated vehicle mass parameter value and the grade of incline parameter value.

10. The vehicle of claim 1 wherein the grade of incline is rendered by a grade calculator based upon a set of forces operating upon the vehicle, the mass resulting in linear acceleration of the vehicle.

11. The vehicle of claim 1 wherein the grade of incline is rendered from a direct measure of current grade.

12. The vehicle of claim 1 wherein the programmed controller includes a filter/average for rendering a filtered/averaged output value for at least one of the group consisting of: the vehicle mass parameter value and the grade of incline parameter value.

13. A method, performed by a programmed controller configured by computer-executable instructions, for providing a vehicle parameter value pertinent to control of an automatic transmission within a vehicle including an automatic transmission, the vehicle generating a set of sensor inputs providing values indicating a current operational status of the vehicle and pertinent to controlling the automatic transmission, and wherein the set of sensor inputs include: engine speed, engine torque, current transmission gear; and vehicle speed, the method comprising:
iteratively and co-dependently performing, by the programmed controller, the steps of:
generating a current vehicle mass parameter value based upon a previously generated grade of incline parameter value, and
generating a current grade of incline parameter value based upon a previously generated vehicle mass parameter value,
wherein, in addition to the previously generated grade of incline parameter value, the generating the vehicle mass parameter is based upon a set of parameters including:
a propulsive force driving the vehicle,
a set of forces acting on the vehicle resisting forward movement, and
an observed rate of change of a speed of the vehicle; and
issuing, by the programmed controller, an output signal to the automatic transmission, the output signal being based upon at least one of the current vehicle mass parameter value and the current grade of incline parameter value.

14. The method of claim 13 further comprising:
issuing a command to reset a current value for the vehicle mass parameter value during a period of mechanical instability.

15. The method of claim 14 wherein the period of mechanical instability arises from a dumping operation by the vehicle.

16. The method of claim 14 wherein the period of mechanical instability arises from a turning operation of the vehicle.

Assignees

• Caterpillar Inc

Inventors

• Siegel Bryan T
• Jacobson Evan E
• Zhang Yanchai

Classifications

• F16H59/52 Primary

  dependent on the weight of the machine, e.g. change in weight resulting from passengers boarding a bus · CPC title

• F16H61/00 Primary

  Control functions within {control units of} change-speed- or reversing-gearings for conveying rotary motion {; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing} · CPC title

• F16H61/0213 Primary

  characterised by the method for generating shift signals · CPC title

• F16H2059/663

  Road slope · CPC title

• F16H2061/0227

  Shift map selection, i.e. methods for controlling selection between different shift maps, e.g. to initiate switch to a map for up-hill driving · CPC title