DETERMINATION OF ACCELERATION BEHAVIOUR

• US 20120130611A1
• Filed: 11/17/2009
• Published: 05/24/2012
• Est. Priority Date: 11/26/2008
• Status: Active Grant

• Current Assignee: Scania CV AB (Volkswagen AG)
• Original Assignee: Scania CV AB (Volkswagen AG)
• Inventors: Al Alam, Assad, Andersson, Jon, Sahlholm, Per
• Granted Patent: US 8,494,744 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2530/10 Weight
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2720/103 Speed profile
• CPC Class Codes: B60W 2720/106 Longitudinal acceleration
• CPC Class Codes: B60W 30/143 Speed control B60W30/16 takes precedence
• CPC Class Codes: B60W 30/188 Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: B60W 30/1882 characterised by the working point of the engine, e.g. by using engine output chart

Abstract

A method and control unit for determining a fuel efficient acceleration behavior of a motor vehicle for a predetermined road section is disclosed. The determination of the acceleration behaviour is based on a determined initial speed of the motor vehicle in a first position in the road section, and a determined target speed of the motor vehicle in a determined second position in the road section, wherein the second position is separated from the first position by an acceleration distance. According to the present invention, the first position is determined such that the acceleration distance is shorter than or equal to a maximal acceleration distance S_acc, wherein the maximal acceleration distance S_acc is dynamically determined based on at least one first road condition for the road section and on at least one characteristic of the motor vehicle. An intuitively acceptable acceleration behaviour is achieved, which at the same time is very fuel efficient.

Claims

1. A method for determining and setting a fuel efficient acceleration behavior of a motor vehicle for a predetermined road section comprising:

determining an initial speed of said motor vehicle in a first position in said road section, and

determining a target speed of said motor vehicle in a determined second position in said road section, wherein said second position is separated from said first position by an acceleration distance;

dynamically determining a maximal acceleration distance S_acc based on at least one first road condition for said road section and on at least one characteristic of said motor vehicle and said first position is determined such that said acceleration distance is shorter than or equal to said maximal acceleration distance S_acc; and

setting said initial and target speeds and said acceleration distance based on said determined initial and target speeds and acceleration distance.

2. The method as claimed in claim 1, further comprising an acceleration to be performed within said acceleration distance has a property that is determined based on at least one second road condition for said road section.

3. The method as claimed in claim 2, wherein each of said at least one first and said at least second road conditions is related to at least one road condition selected from a group consisting of:

a topology for at least one part of said road section, at least one desired speed for at least one part of said road section, a straightness of at least one part of said road section, a traffic situation for at least one part of said road section, a number of vehicles other than said motor vehicle present on at least one part of the road section.

4. The method as claimed in claim 1, wherein said at least one characteristic of said motor vehicle is related to revolutions per minute (rpm) and/or a momentum of an engine of said motor vehicle.

5. The method as claimed in claim 1, wherein said at least one characteristic of said motor vehicle is related to at least one of motor vehicle specific parameters or features selected from a group consisting of:

weight, engine characteristics, air resistance, transmission, brake system, roll resistance, total gear ratio, inertial forces, various frictions forces of or on the vehicle.

6. The method as claimed in claim 5, wherein said maximal acceleration distance S_acc is determined according to:

7. The method as claimed in claim 1, wherein said maximal acceleration distance S_acc is determined based also on at least one input from a driver of said motor vehicle.

8. The method as claimed in claim 7, wherein said driver input is chosen according to any value selected from a group consisting of:

a value corresponding to an arbitrary maximal acceleration distance S_acc;

a value corresponding to one adjustment coefficient in a set of predefined adjustment coefficients, wherein said predefined adjustment coefficients are to be multiplied with said maximal acceleration distance S_acc;

a value corresponding to a speed change dependent maximal acceleration distance S_acc.

9. The method as claimed in claim 8, wherein said speed change dependent maximal acceleration distance S_acc is dependent on an actual location on said road section where an acceleration is to be performed.

10. The method as claimed in claim 1, wherein a length of said predetermined road section is adjustable.

12. Method for an automated speed control of a motor vehicle based on the acceleration behavior determined as claimed in claim 1 and further comprising performing said acceleration from an initial speed to a target speed using a speed altering device of said motor vehicle.

13. A computer program, which is run in a control unit of a motor vehicle, the program being configured to cause the control unit to execute the method according to claim 1.

14. A computer program product including a computer readable medium and a computer program according to claim 13, wherein said computer program is included in the computer readable medium.

15. A computer program product according to claim 14, further comprising said computer readable medium consists of one or more devices selected from the group consisting of:

ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), Flash memory, EEPROM (Electrically Erasable PROM).

11. The method as claimed in 7, wherein said maximal acceleration distance S_acc is determined such that said acceleration input by a driver of said vehicle is perceived as resembling an acceleration on a level road.

16. A control unit for determining a fuel efficient acceleration behavior of a motor vehicle for a predetermined road section, said control unit including:

a determination apparatus configured and operable for determining said acceleration behaviour based on;

a determined initial speed of said motor vehicle in a first position in said road section; and

a determined target speed of said motor vehicle in a determined second position in said road section, said second position being separated from said first position by an acceleration distance;

said control unit including a first device configured and operable for determining said first position such that said acceleration distance is shorter than or equal to a maximal acceleration distance S_acc; and

a second device for dynamically determining said maximal acceleration distance S_acc based on at least one first road condition of said road section and on at least one characteristic of said motor vehicle.

17. The control unit as claimed in claim 16, wherein said control unit includes a third device configured and operable for determining a property of an acceleration to be performed within said acceleration distance based on at least one second road condition for said road section.

18. The control unit as claimed in claim 17, wherein said third device for dynamically determining said maximal acceleration distance S_acc is connected at least to a reception device configured and operable for receiving:

positioning information concerning said vehicle;

electronic map information;

information related to said at least one road condition; and

information related to said at least one characteristic of said motor vehicle.

19. The control unit as claimed in claim 18, wherein said third device is configured and operable for dynamically determining said maximal acceleration distance S_acc and is connected to said reception device arranged for also receiving at least one input from a driver of said motor vehicle.

20. The control unit as claimed in claim 19, wherein said reception device is configured and operable to receive one type of input selected from the group consisting of:

a value corresponding to an arbitrary maximal acceleration distance S_acc, and a value corresponding to one adjustment coefficient in a set of predefined adjustment coefficients, and to multiply said predefined adjustment coefficients with said maximal acceleration distance S_acc.

21. The control unit as claimed in claim 16, further comprising said control unit includes adjustment means arranged for adjusting a length of said predetermined road section.

22. A system for an automated speed control of a motor vehicle, comprising:

the control unit as claimed in claim 16; and

a speed altering device of said motor vehicle configured and operable so as to be controlled by said control unit.