VEHICLE BODY SPEED ESTIMATING DEVICE

• US 20100198448A1
• Filed: 09/09/2008
• Published: 08/05/2010
• Est. Priority Date: 09/14/2007
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Miura, Yumiko, Ono, Eiichi, Yamaguchi, Katsuyuki, Yasutomi, Taisuke
• Granted Patent: US 8,457,832 B2
• Time in Patent Office: Days
• US Class Current: 701/29
• CPC Class Codes: B60G 17/0182 involving parameter estimation, e.g. observer, Kalman filter
• CPC Class Codes: B60G 2400/051 Angle
• CPC Class Codes: B60G 2400/0511 Roll angle
• CPC Class Codes: B60G 2400/0512 Pitch angle
• CPC Class Codes: B60G 2400/0523 Yaw rate
• CPC Class Codes: B60G 2400/104 lateral or transversal with regard to vehicle
• CPC Class Codes: B60G 2400/106 longitudinal with regard to vehicle, e.g. braking
• CPC Class Codes: B60G 2400/204 Vehicle speed
• CPC Class Codes: B60G 2400/2042 Lateral speed
• CPC Class Codes: B60G 2400/208 of wheel rotation
• CPC Class Codes: B60G 2600/09 Feedback signal
• CPC Class Codes: B60G 2600/1872 Observer; Luaponov function
• CPC Class Codes: B60G 2600/70 Computer memory; Data storage, e.g. maps for adaptive control
• CPC Class Codes: B60W 2050/0033 Single-track, 2D vehicle model, i.e. two-wheel bicycle model
• CPC Class Codes: B60W 40/105 Speed
• CPC Class Codes: B60W 40/109 Lateral acceleration
• CPC Class Codes: B60W 40/11 Pitch movement
• CPC Class Codes: B60W 40/112 Roll movement
• CPC Class Codes: B60W 40/114 Yaw movement

Abstract

A vehicle body speed estimating device. An attitude angle estimating mechanism estimates a roll angle and a pitch angle. A longitudinal speed computing mechanism computes longitudinal vehicle body speed. A vehicle body speed estimator estimates lateral vehicle body speed by using, as state amounts of vehicle motion, the longitudinal vehicle body speed and the lateral vehicle body speed, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration and yaw angular velocity of vehicle motion, and respective estimated values of the roll angle and the pitch angle, and a product of a computed value of the longitudinal vehicle body speed and a value obtained from an absolute value of the detected value of the yaw angular velocity.

Claims

1. A vehicle body speed estimating device comprising:

an attitude angle estimating means that estimates a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

a longitudinal speed computing means that computes longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

a vehicle body speed estimating means that estimates lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed and the lateral vehicle body speed, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration and yaw angular velocity of vehicle motion, and respective estimated values of the roll angle and the pitch angle, and a product of a computed value of the longitudinal vehicle body speed and a value obtained from an absolute value of the detected value of the yaw angular velocity.

2. The vehicle body speed estimating device of claim 1, wherein the vehicle body speed estimating means estimates the lateral vehicle body speed by adding, to the state amounts, a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing, and by adding a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing, and a detected value of a vehicle steering angle.

3. A vehicle body speed estimating device comprising:

an attitude angle estimating means that estimates a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

a longitudinal speed computing means that computes longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

a vehicle body speed estimating means that estimates lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed, the lateral vehicle body speed and a value obtained by subjecting a detected value of lateral acceleration to low-pass filtering processing, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration, yaw angular velocity and a vehicle steering angle of vehicle motion, and respective estimated values of the roll angle and the pitch angle, and a corrected value of a computed value of the longitudinal vehicle body speed that is corrected in accordance with an estimated value of a pitch angle with respect to a road surface that is estimated from the detected value of the longitudinal acceleration, and a computed value of vertical vehicle body speed obtained by correcting the detected value of the longitudinal acceleration in accordance with the estimated value of the pitch angle, and a product of a corrected value of a computed value of the longitudinal vehicle body speed and a value obtained from an absolute value of the detected value of the yaw angular velocity, and a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing, and a detected value or an estimated value of roll angular velocity, and a detected value or an estimated value of pitch angular velocity.

4. A vehicle body speed estimating device comprising:

an attitude angle estimating means that estimates a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

a longitudinal speed computing means that computes longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

a vehicle body speed estimating means that estimates the longitudinal vehicle body speed and lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed and the lateral vehicle body speed, and by using, as a feedback amount, a product of a deviation between a computed value of the longitudinal vehicle body speed and an estimated value of the longitudinal vehicle body speed, and a value obtained from an absolute value of a detected value of a yaw angular velocity, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration and yaw angular velocity of vehicle motion, and respective estimated values of the roll angle and the pitch angle, and a product of the deviation and a value obtained from the absolute value of the detected value of the yaw angular velocity.

5. The vehicle body speed estimating device of claim 4, wherein the vehicle body speed estimating means estimates the longitudinal vehicle body speed and the lateral vehicle body speed by adding, to the state amounts, a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing, and by adding, to the feedback amount, a deviation between a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing and an estimated value of the value obtained by low-pass filter processing, and by adding a deviation between the value obtained by low-pass filter processing and the estimated value of the value obtained by low-pass filter processing, and a detected value of a vehicle steering angle.

6. A vehicle body speed estimating device comprising:

an attitude angle estimating means that estimates a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

a longitudinal speed computing means that computes longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

a vehicle body speed estimating means that estimates the longitudinal vehicle body speed and lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed, the lateral vehicle body speed, and a value obtained by subjecting a detected value of lateral acceleration to low-pass filter processing, and by using, as feedback amounts, a product of a first deviation, that is a deviation between a corrected value of a computed value of the longitudinal vehicle body speed that is corrected in accordance with an estimated value of the pitch angle with respect to a road surface that is estimated from a detected value of longitudinal acceleration, and an estimated value of a corrected value of the longitudinal vehicle body speed, and a value obtained from an absolute value of a detected value of a yaw angular velocity, and a second deviation that is a deviation between a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing and an estimated value of the value obtained by low-pass filter processing, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration, yaw angular velocity and a vehicle steering angle of vehicle motion, and a computed value of vertical vehicle body speed that is obtained by correcting the detected value of the longitudinal acceleration in accordance with the product, the second deviation and an estimated value of the pitch angle, and respective estimated values of the roll angle and the pitch angle, and a detected value or an estimated value of roll angular velocity, and a detected value or an estimated value of pitch angular velocity.

7-10. -10. (canceled)

11. A storage medium readable by a computer, the storage medium storing a program of instructions executable by the computer to perform a function for estimating vehicle body speed, the function comprising the steps of:

estimating a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

computing longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

estimating lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed and the lateral vehicle body speed, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration and yaw angular velocity of vehicle motion, and respective estimated values of the roll angle and the pitch angle, and a product of a computed value of the longitudinal vehicle body speed and a value obtained from an absolute value of the detected value of the yaw angular velocity.

12. A storage medium readable by a computer, the storage medium storing a program of instructions executable by the computer to perform a function for estimating vehicle body speed, the function comprising the steps of:

estimating a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

computing longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

estimating lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed, the lateral vehicle body speed and a value obtained by subjecting a detected value of lateral acceleration to low-pass filtering processing, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration, yaw angular velocity and a vehicle steering angle of vehicle motion, and respective estimated values of the roll angle and the pitch angle, and a corrected value of a computed value of the longitudinal vehicle body speed that is corrected in accordance with an estimated value of a pitch angle with respect to a road surface that is estimated from the detected value of the longitudinal acceleration, and a computed value of vertical vehicle body speed obtained by correcting the detected value of the longitudinal acceleration in accordance with the estimated value of the pitch angle, and a product of a corrected value of a computed value of the longitudinal vehicle body speed and a value obtained from an absolute value of the detected value of the yaw angular velocity, and a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing, and a detected value or an estimated value of roll angular velocity, and a detected value or an estimated value of pitch angular velocity.

13. A storage medium readable by a computer, the storage medium storing a program of instructions executable by the computer to perform a function for estimating vehicle body speed, the function comprising the steps of:

estimating a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

computing longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

estimating the longitudinal vehicle body speed and lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed and the lateral vehicle body speed, and by using, as a feedback amount, a product of a deviation between a computed value of the longitudinal vehicle body speed and an estimated value of the longitudinal vehicle body speed, and a value obtained from an absolute value of a detected value of a yaw angular velocity, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration and yaw angular velocity of vehicle motion, and respective estimated values of the roll angle and the pitch angle, and a product of the deviation and a value obtained from the absolute value of the detected value of the yaw angular velocity.

14. A storage medium readable by a computer, the storage medium storing a program of instructions executable by the computer to perform a function for estimating vehicle body speed, the function comprising the steps of:

estimating a roll angle and a pitch angle that are attitude angles with respect to a vertical axis of a vehicle body;

computing longitudinal vehicle body speed that is vehicle body speed in a vehicle longitudinal direction, on the basis of wheel speeds of respective wheels; and

estimating the longitudinal vehicle body speed and lateral vehicle body speed that is vehicle body speed in a vehicle lateral direction by using, as state amounts of vehicle motion, the longitudinal vehicle body speed, the lateral vehicle body speed, and a value obtained by subjecting a detected value of lateral acceleration to low-pass filter processing, and by using, as feedback amounts, a product of a first deviation, that is a deviation between a corrected value of a computed value of the longitudinal vehicle body speed that is corrected in accordance with an estimated value of the pitch angle with respect to a road surface that is estimated from a detected value of longitudinal acceleration, and an estimated value of a corrected value of the longitudinal vehicle body speed, and a value obtained from an absolute value of a detected value of a yaw angular velocity, and a second deviation that is a deviation between a value obtained by subjecting the detected value of the lateral acceleration to low-pass filter processing and an estimated value of the value obtained by low-pass filter processing, and on the basis of respective detected values of longitudinal acceleration, lateral acceleration, yaw angular velocity and a vehicle steering angle of vehicle motion, and a computed value of vertical vehicle body speed that is obtained by correcting the detected value of the longitudinal acceleration in accordance with the product, the second deviation and an estimated value of the pitch angle, and respective estimated values of the roll angle and the pitch angle, and a detected value or an estimated value of roll angular velocity, and a detected value or an estimated value of pitch angular velocity.