Method of learning torque-stroke curve of electric motor controlled dry clutch system

Patent metadata

Field	Value
Publication number	US-10094435-B2
Application number	US-201615297991-A
Country	US
Kind code	B2
Filing date	Oct 19, 2016
Priority date	Oct 20, 2015
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

A method for learning a torque-stroke (T-S) curve of an electric motor controlled dry clutch system is disclosed. The method includes calculating a position change value A for allowing a position change point P 3 corresponding to an arbitrary torque y 3 on a previous T-S curve C 1 to follow-up and be moved to an expectation T-S curve C 3 , by a control unit, calculating a probability Pr_X 3 to allow the position change value A to consider various environmental factors of a clutch within a valid range, and multiplying the probability Pr_X 3 to the position change value A to calculate a final position change value A, by the control unit, and calculating a new point P 3 by applying the final position change value A to the position change point P 3 of the previous T-S curve C 1 , and generating a final T-S curve connecting the new point P 3 and a touch point to learn, by the control unit.

First claim

What is claimed is:

1. A method for learning a torque-stroke (T-S) curve of an electric motor controlled dry clutch system, the method comprising:
calculating, by a control unit, a position change value A for allowing a position change point P 3 corresponding to an arbitrary torque y 3 on a previous T-S curve C 1 to follow-up and be moved to an expectation T-S curve C 3 ;
calculating, by the control unit, a probability Pr_X 3 to allow a consideration of various environmental factors of a clutch based on a maximum value of a valid range in which the position change value A varies, and multiplying the probability Pr_X 3 to the position change value A to calculate a final position change value A;
calculating, by the control unit, a new point P 3 by applying the final position change value A to the position change point P 3 of the previous T-S curve C 1 , and generating a final T-S curve connecting the new point P 3 and a touch point; and
controlling, by the control unit, a stroke of an electric motor based on the final T-S curve so that a dry clutch transmits a target torque from an engine, the electric motor changing a position of the dry clutch.

2. The method of claim 1 ,
wherein the step of calculating a position change value A comprises:
moving, by the control unit, the position change point P 3 corresponding to the arbitrary torque y 3 on the previous T-S curve C 1 by a predetermined unit bias;
generating, by the control unit, a virtual T-S curve C 2 connecting the point P 3 of which position is moved by the unit bias on the previous T-S curve C 1 and the touch point;
calculating, by the control unit, a difference value X between a position at an adaptation point of the virtual T-S curve C 2 and a position at an adaptation point of the previous T-S curve C 1 corresponding to a torque of the adaptation point of the virtual T-S curve C 2 ;
calculating, by the control unit, a position change amount Δpos at the adaptation point of an expectation T-S curve C 3 corresponding to a torque of the previous T-S curve C 1 ; and
calculating, by the control unit, the position change value A based on a position difference value X at the adaptation points of the previous T-S curve C 1 and the virtual T-S curve C 2 , and a position variation amount Δpos at the adaptation points of the previous T-S curve C 1 and the expectation T-S curve C 3 .

3. The method of claim 2 ,
wherein the previous T-S curve C 1 , the virtual T-S curve C 2 , and the expectation T-S curve C 3 are generated by connecting the touch point and position change points of each of the T-S curves C 1 , C 2 and C 3 in a spline curve shape using a spline function.

4. The method of claim 3 ,
wherein the previous T-S curve C 1 is a T-S curve stored initially or a T-S curve learned and stored previously,
the expectation T-S curve C 3 is a T-S curve generated by connecting the position points corresponding to respective torque at entire regions while a vehicle actually drives, and
the virtual T-S curve C 2 is a T-S curve generated by connecting a point P 3 of which position is moved on the previous T-S curve C 1 by the unit bias and the touch point.

5. The method of claim 2 , wherein the unit bias is set to 1 mm.

6. The method of claim 1 , wherein the probability Pr_X 3 corresponds to a resulting value of a probability density function that is calculated on a basis of a normal distribution curve of the position change value A.

7. The method of claim 6 , wherein the probability Pr_X 3 is expressed as an equation of:

1

σ
⁢

⁢
1
⁢

2
⁢

⁢
π

⁢

e

-

a
2

2
⁢

⁢
σ
⁢

⁢

1
2

wherein σ1 is a standard deviation of aMax/2, the aMax is the maximum value, and a is the position change value at P 3 .

Assignees

• Hyundai Autron Co Ltd

Inventors

• Park Seong Jin

Classifications

• F16D2500/1023

  Electric motor · CPC title

• F16D2500/70205

  Clutch actuator · CPC title

• F16D2500/7082

  of the clutch · CPC title

• F16D2500/5012

  Accurate determination of the clutch positions, e.g. treating the signal from the position sensor, or by using two position sensors for determination · CPC title

• F16D48/064 Primary

  Control of electrically or electromagnetically actuated clutches (F16D48/062, F16D48/068 take precedence) · CPC title