Vehicle Mass Detection System

• US 20140277867A1
• Filed: 03/12/2013
• Published: 09/18/2014
• Est. Priority Date: 03/12/2013
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Nedorezov, Felix, Jiang, Hong, Shelton, Matthew John, Colvin, Daniel, Dai, Zhengyu, Huffmaster, Roger Lyle
• Granted Patent: US 8,892,291 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2510/083 Torque
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2530/20 Tyre data
• CPC Class Codes: B60W 40/13 Load or weight
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility
• CPC Class Codes: Y10S 903/93 Conjoint control of different elements

Abstract

A vehicle system and a method for calculating a vehicle mass is provided. In at least one embodiment, the system and the method measure current consumed by an electric machine of the vehicle to calculate vehicle mass. A controller of the vehicle uses the calculated mass to control operation of the vehicle, for example a four wheel drive, transmission, stability control, or brake system of the vehicle. A GPS and tire speed sensor system may be incorporated to detect the presence of a towed object, for example a trailer, and to further adjust operation of the vehicle.

Claims

1. A method of controlling a vehicle including an electric machine based on vehicle mass, the method comprising:

while a speed of the electric machine is changing, measuring current consumed by the electric machine at two different instances of time;

calculating a mass of the vehicle based on the measured currents; and

controlling operation of the vehicle according to the calculated mass.

2. The method of claim 1, wherein the step of controlling comprises controlling at least one of a four wheel drive control system, transmission control system, stability control system, and a brakes system according to the calculated mass.

3. The method of claim 1 further comprising maintaining a constant engine propulsive torque while the speed of the electric machine is changing.

4. The method of claim 1 further comprising disconnecting an engine of the vehicle such that the engine provides no propulsive torque while the speed of the electric machine is changing.

5. The method of claim 1 further comprising tracking a distance traveled by the vehicle and a number of tire revolutions of the vehicle for the distance traveled and comparing the distance traveled and the number of tire revolutions to stored data corresponding to a number of tire revolutions for the distance traveled at a given mass of the vehicle, wherein controlling operation of the vehicle according to the calculated mass includes adjusting operation of the vehicle according to the comparison.

7. The method of claim 5 further comprising detecting a presence of a towed object attached to the vehicle based on at least one of the measured currents and the comparison.

8. The method of claim 7, wherein if no towed object is detected, a correction factor is created for the adjustment of the operation of the vehicle based on the measured currents.

6. The method of 5, wherein the stored data further comprises data corresponding to a number of tire revolutions for the distance traveled at a plurality of vehicle masses.

9. A vehicle comprising:

an electric machine;

a driveline;

a traction battery; and

at least one controller programmed to command the electric machine to apply a braking torque to the driveline of the vehicle based on a mass of the vehicle such that when the electric machine is outputting a propulsive torque to the driveline, a magnitude of current from the electric machine to the traction battery varies according to the mass of the vehicle and when the electric machine is not outputting a propulsive torque to the driveline, the magnitude of the current remains generally constant.

10. A vehicle system comprising:

an electric machine; and

at least one controller programmed to control operation of the vehicle based on current consumed by the electric machine at different instances of time while the vehicle is accelerating.

11. The system of claim 10, wherein the at least one controller is programmed to control at least one of a four wheel drive control system, transmission control system, stability control system, and a brakes system based on current consumed by the electric machine at different instances of time while the vehicle is accelerating.

12. The system of claim 10 further comprising an engine configured to output a constant propulsive torque during and between the different instances of time while the vehicle is accelerating.

13. The system of claim 10 further comprising an engine configured to output no propulsive torque during and between the different instances of time while the vehicle is accelerating.

14. The system of claim 10 further comprising a global positioning system (GPS) in communication with the at least one controller and configured to track a distance traveled by the vehicle and at least one tire speed sensor configured to measure a number of tire revolutions of the vehicle for the distance traveled, wherein the at least one controller is further programmed to compare the distance traveled and the number of tire revolutions to stored data corresponding to a number of tire revolutions for the distance traveled at a given mass of the vehicle and to adjust operation of the vehicle based on the current consumed according to the comparison.

15. The system of claim 14, wherein the stored data further comprises data corresponding to a number of tire revolutions for the distance traveled at a plurality of vehicle masses.

16. The system of claim 10, wherein the at least one controller is further programmed to control operation of the vehicle based on current consumed by the electric machine at two different instances of time while the vehicle is accelerating.

17. The system of claim 10, wherein the at least one controller is further programmed to control operation of the vehicle based on current consumed by the electric machine at four different instances of time while the vehicle is accelerating.