METHOD FOR HILL START ASSISTANCE FOR MOTOR VEHICLE

• US 20100241328A1
• Filed: 08/18/2008
• Published: 09/23/2010
• Est. Priority Date: 09/25/2007
• Status: Active Grant

• Current Assignee: Renault Sas (Renault)
• Original Assignee: Renault Sas (Renault)
• Inventors: Le Vourch, Yves, Mallet, Mickael, Pothin, Richard, De Rinaldis, Alessandro
• Granted Patent: US 8,463,517 B2
• Time in Patent Office: Days
• US Class Current: 701/68
• CPC Class Codes: F16D 2500/10412 Transmission line of a vehicle
• CPC Class Codes: F16D 2500/30425 Estimation of the transmitted clutch torque, e.g. applying dynamic torque balance equation
• CPC Class Codes: F16D 2500/3065 Torque of the engine
• CPC Class Codes: F16D 2500/3067 Speed of the engine
• CPC Class Codes: F16D 2500/3161 Signal providing information about the state of engine accessories
• CPC Class Codes: F16D 2500/3165 Using the moment of inertia of a component as input for the control
• CPC Class Codes: F16D 2500/50287 Torque control
• CPC Class Codes: F16D 2500/50841 Hill hold
• CPC Class Codes: F16D 2500/7044 Output shaft torque
• CPC Class Codes: F16D 2500/7049 Brake parameters
• CPC Class Codes: F16D 2500/70668 Signal filtering
• CPC Class Codes: F16D 48/08 Regulating clutch take-up on starting

Abstract

A method for hill start assistance for a motor vehicle and to an associated device that includes a clutch and a transmission between the clutch and driving wheels of the vehicle. The method determines the torque of the clutch for maintaining the vehicle in an immobile position based on a known engine torque, wherein the torque of the clutch is determined by taking into account a portion of the engine torque dedicated to operation of constituent mechanisms of the vehicle other than the clutch.

Claims

1-9. -9. (canceled)

10. A hill start assistance method for a motor vehicle including a clutch and a transmission between the clutch and drive wheels of the vehicle, the method comprising:

determining clutch torque to keep the vehicle immobile based on knowledge of engine torque (C_me),

wherein the clutch torque (C_emb) is determined by taking into account a proportion of engine torque dedicated to an operation of constituent mechanism of the vehicle other than the clutch.

11. The method as claimed in claim 10, wherein, to determine the proportion of the engine torque dedicated to the operation of the constituent mechanisms of the vehicle other than the clutch, an account is taken of an equivalent torque Jω

_m associated with mechanisms of the engine exhibiting a rotary movement dependent on engine speed, in which J is an equivalent moment of inertia of the engine mechanisms exhibiting a rotary movement dependent on the engine speed and ω

_m is derivative of the engine speed.

12. The method as claimed in claim 11, wherein, to determine the derivative of the engine speed, the speed of rotation of the engine is measured by a dedicated sensor, then the obtained speed is derived by a computation mechanism on board the vehicle.

13. The method as claimed in claim 10, wherein, to determine the proportion of the engine torque dedicated to the operation of the constituent mechanisms of the vehicle other than the clutch, an equivalent torque C_me,off is estimated that corresponds to quota of engine torque dedicated to an operation of accessories of the vehicle.

14. The method as claimed in claim 13, wherein the equivalent torque C_me,off associated with the accessories of the vehicle is estimated, by considering the latter to he the residual value of the engine torque C_me when:

the engine is declutched;

the engine speed is stabilized;

in absence of any action on the vehicle'"'"'s accelerator pedal.

15. The method as claimed in claim 14, wherein the clutch torque is determined by relation C_emb=C_me−

C_me,off−

Jω

_m (1), corresponding to a sum of moments exerted on the transmission between the clutch and the drive wheels of the vehicle.

16. The method as claimed in claim 14, wherein the clutch torque is determined by the system formed by following relations:

17. A hill start assistance device for a motor vehicle, comprising:

a clutch;

a transmission between the clutch and the drive wheels of the vehicle; and

brakes and computation means managing, based on knowledge of the engine torque, pressure applied to the brakes to keep the vehicle immobile, wherein the computation means are arranged so that clutch torque is determined by taking account of a proportion of engine torque dedicated to an operation of constituent mechanisms of the vehicle other than the clutch.

18. A motor vehicle, comprising a device as claimed in claim 17.