Method for measuring vertical acceleration and velocity of semi-active suspension system

• US 20070100522A1
• Filed: 11/02/2005
• Published: 05/03/2007
• Est. Priority Date: 11/02/2005
• Status: Active Grant

• Current Assignee: HL Mando Corporation (Halla Holdings Corporation)
• Original Assignee: Mando Corporation
• Inventors: Kim, Wan Il, Lee, Jeong
• Granted Patent: US 7,627,408 B2
• Time in Patent Office: Days
• US Class Current: 701/37
• CPC Class Codes: B60G 17/0152 characterised by the action on a particular type of suspension unit B60G17/01941 takes precedence
• CPC Class Codes: B60G 17/01908 Acceleration or inclination sensors characterised by the use of gyroscopes B60G21/08
• CPC Class Codes: B60G 2400/102 vertical
• CPC Class Codes: B60G 2500/10 Damping action or damper
• CPC Class Codes: B60G 2500/20 Spring action or springs
• CPC Class Codes: B60G 2600/12 Sampling or average detecting; Addition or substraction
• CPC Class Codes: B60G 2600/90 other signal treatment means

Abstract

The present invention relates to a method for measuring a vertical acceleration and a velocity of a semi-active suspension system. Particularly, the present invention provides a method for obtaining a vertical acceleration from vertical accelerations measured from three vertical acceleration sensors of a semi-active suspension system of a vehicle, comprising the steps of: receiving first to third vertical accelerations measured from first to third vertical acceleration sensors; and obtaining a fourth vertical acceleration (Ad) by multiplying the first to third vertical accelerations by correction constants and subsequently summing up them. Therefore, according to the present invention, a fourth vertical acceleration can be obtained by multiplying the three vertical accelerations measured from the three acceleration sensors by the constants for correcting them to accelerations at actually desired damper positions and subsequently summing up them, thereby enabling accurate measurement and correction of the vertical accelerations.

Claims

1. A method for obtaining a vertical acceleration from vertical accelerations measured from three vertical acceleration sensors of a semi-active suspension system of a vehicle, comprising the steps of:

receiving first to third vertical accelerations measured from first to third vertical acceleration sensors; and

obtaining a fourth vertical acceleration (Ad) by multiplying the first to third vertical accelerations by correction constants and subsequently summing up them, according to the following equation;

Ad=α

^xAα

1+β

^xAα

2+γ

^xAα

3,

where α

, β and

γ

are the correction constants at the position of a damper where a vertical acceleration sensor is not installed, Ad is the fourth vertical acceleration, and Aa1, Aa2 and Aa3 are the first to third vertical accelerations, respectively.

2. The method as claimed in claim 1, wherein the correction constants α

, β and

γ

are obtained from the following equations using X and Y position coordinate values of the first to third vertical acceleration sensors and x and y position coordinate values of the damper where a vertical acceleration sensor is not installed;

$\mathrm{\alpha <br><br>}<br><br>\left(x,y\right)=\frac{\left(Y_2-Y_3\right)<br><br>x+\left(X_3-X_2\right)<br><br>y+X_2<br><br>Y_3-X_3<br><br>Y_2}{\left(X_1-X_2\right)<br><br>\left(Y_1-Y_3\right)-\left(X_1-X_3\right)<br><br>\left(Y_1-Y_2\right)}$ $\mathrm{\beta <br><br>}<br><br>\left(x,y\right)=\frac{\left(Y_3-Y_1\right)<br><br>x+\left(X_1-X_3\right)<br><br>y+X_3<br><br>Y_1-X_1<br><br>Y_3}{\left(X_1-X_2\right)<br><br>\left(Y_1-Y_3\right)-\left(X_1-X_3\right)<br><br>\left(Y_1-Y_2\right)}$ $\mathrm{\gamma <br><br>}<br><br>\left(x,y\right)=\frac{\left(Y_1-Y_2\right)<br><br>x+\left(X_2-X_1\right)<br><br>y+X_1<br><br>Y_2-X_2<br><br>Y_1}{\left(X_1-X_2\right)<br><br>\left(Y_1-Y_3\right)-\left(X_1-X_3\right)<br><br>\left(Y_1-Y_2\right)},$

where X₁, X₂ and X₃ are X position coordinate values of the first to third vertical acceleration sensors, Y₁, Y₂ and Y₃ are Y position coordinate values of the first to third vertical acceleration sensors, and x and y are X and Y position coordinate values of the damper where a vertical acceleration sensor is not installed.

3. The method as claimed in claim 1 or 2, after the step of obtaining the fourth vertical acceleration, further comprising the step of correcting the first to third vertical accelerations measured from the vertical acceleration sensors to vertical accelerations at the positions of corresponding dampers using the following equations:

Aα

_n[1]=α

[1]×

Aα

[1]+β

[1]×

Aα

[2]+β

[1]×

Aα

[3]
Aα

_n[2]=α

[2]×

Aα

[1]+β

[2]×

Aα

[2]+β

[2]×

Aα

[3]
Aα

_n[3]=α

[3]×

Aα

[1]+β

[3]×

Aα

[2]+β

[3]×

Aα

[3],

where Aa_n[1], Aa_n[2] and Aa_n[3] are values corrected to the vertical accelerations at the positions of first to third dampers, α

[1], β

[1] and γ

[1] are correction constants at the position of the first damper, α

[2], β

[2] and γ

[2] are correction constants at the position of the second damper, and α

[3], β

[3] and γ

[3] are correction constants at the position of the third damper.

4. A method for obtaining a velocity from velocities measured from three velocity sensors of a semi-active suspension system of a vehicle, comprising the steps of:

receiving first to third velocities measured from first to third velocity sensors; and

obtaining a fourth velocity (Vd) by multiplying the first to third velocities by correction constants and subsequently summing up them, according to the following equation;

Vd=α

^xVα

1+β

^xVα

2+γ

^xVα

3,

where α

, β and

γ

are the correction constants at the position of a damper where a velocity sensor is not installed, Vd is the fourth velocity, and Va1, Va2 and Va3 are the first to third velocities, respectively.

5. The method as claimed in claim 4, wherein the correction constants α

, β and

γ

are obtained from the following equations using X and Y position coordinate values of the first to third velocity sensors and x and y position coordinate values of the damper where a vertical acceleration sensor is not installed;

$\mathrm{\alpha <br><br>}<br><br>\left(x,y\right)=\frac{\left(Y_2-Y_3\right)<br><br>x+\left(X_3-X_2\right)<br><br>y+X_2<br><br>Y_3-X_3<br><br>Y_2}{\left(X_1-X_2\right)<br><br>\left(Y_1-Y_3\right)-\left(X_1-X_3\right)<br><br>\left(Y_1-Y_2\right)}$ $\mathrm{\beta <br><br>}<br><br>\left(x,y\right)=\frac{\left(Y_3-Y_1\right)<br><br>x+\left(X_1-X_3\right)<br><br>y+X_3<br><br>Y_1-X_1<br><br>Y_3}{\left(X_1-X_2\right)<br><br>\left(Y_1-Y_3\right)-\left(X_1-X_3\right)<br><br>\left(Y_1-Y_2\right)}$ $\mathrm{\gamma <br><br>}<br><br>\left(x,y\right)=\frac{\left(Y_1-Y_2\right)<br><br>x+\left(X_2-X_1\right)<br><br>y+X_1<br><br>Y_2-X_2<br><br>Y_1}{\left(X_1-X_2\right)<br><br>\left(Y_1-Y_3\right)-\left(X_1-X_3\right)<br><br>\left(Y_1-Y_2\right)},$

where X₁, X₂ and X₃ are X position coordinate values of the first to third velocity sensors, Y₁, Y₂ and Y₃ are Y position coordinate values of the first to third velocity sensors, and x and y are X and Y position coordinate values of the damper where a vertical acceleration sensor is not installed.

6. The method as claimed in claim 4 or 5, after the step of obtaining the fourth velocity, further comprising the step of correcting the first to third velocities measured from the velocity sensors to velocities at the positions of corresponding dampers using the following equations:

Vα

_n[1]=α

[1]×

Vα

[1]+β

[1]×

Vα

[2]+β

[1]×

Vα

[3]
Vα

_n[2]=α

[2]×

Vα

[1]+β

[2]×

Vα

[2]+β

[2]×

Vα

[3]
Vα

_n[3]=α

[3]×

Vα

[1]+β

[3]×

Vα

[2]+β

[3]×

Vα

[3],

where Va_n[1], Va_n[2] and Va_n[3] are values corrected to the velocities at the positions of first to third dampers, α

[1], β

[1] and γ

[1] are correction constants at the position of the first damper, α

[2], β

[2] and γ

[2] are correction constants at the position of the second damper, and α

[3], β

[3] and γ

[3] are correction constants at the position of the third damper.