Method for hill start assistance for motor vehicle

• US 8,463,517 B2
• Filed: 08/18/2008
• Issued: 06/11/2013
• Est. Priority Date: 09/25/2007
• Status: Active Grant

• Current Assignee: Renault Sas (Renault)
• Original Assignee: Renault Sas (Renault)
• Inventors: De Rinaldis, Alessandro, Mallet, Mickael, Pothin, Richard, Le Vourch, Yves
• Primary Examiner(s): Trammell, James
• Assistant Examiner(s): TESTARDI, DAVID A
• Application Number:
  US12/679,489
• Publication Number:
  US 20100241328A1
• Time in Patent Office: 1,758 Days
• Field of Search: 701/67, 701/68
• US Class Current: 701/67
• 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. 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:

holding the motor vehicle immobile on a hill;

determining via computation means of the vehicle a clutch torque (C_emb) to keep the vehicle immobile based on knowledge of an engine torque (C_me);

estimating an equivalent torque C_me,off as a quota of the engine torque dedicated to an operation of accessories of the vehicle,

determining the clutch torque (C_emb) by a system formed by Equation (2) and Equation (3);

2. The method as claimed in claim 1, wherein the equivalent torque C_me,off associated with the accessories of the vehicle is estimated, by considering C_me,off to be the residual value of the engine torque C_me when:

the engine is declutched;

the engine speed is stabilized; and

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

3. The method as claimed in claim 1, further comprising:

determining the clutch torque (C_emb) by using Equation (2) and Equation (3) as part of a Kalman observer.

4. The method as claimed in claim 1, wherein the accessories of the vehicle include a mechanism selected from the group consisting of an assisted steering mechanism, an engine compartment fan, a passenger compartment fan, and an alternator.

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

a clutch;

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

brakes; and

computation means,

wherein the computation means are configured to

determine a pressure applied to the brakes based on knowledge of an engine torque (C_me) to keep the vehicle immobile,

estimate an equivalent torque C_me,off as a quota of the engine torque dedicated to an operation of accessories of the vehicle, and

determine the clutch torque (C_emb) to keep the vehicle immobile by a system formed by Equation (2) and Equation (3);

6. A motor vehicle, comprising a device as claimed in claim 5.