Attitude-angle detecting apparatus and attitude-angle detecting method

• US 8,200,452 B2
• Filed: 06/25/2007
• Issued: 06/12/2012
• Est. Priority Date: 06/23/2006
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Ueda, Akihiro, Maeda, Iwao, Nagamiya, Kiyomi, Shibata, Naoto
• Primary Examiner(s): KUNDU, SUJOY K
• Application Number:
  US12/306,013
• Publication Number:
  US 20090326858A1
• Time in Patent Office: 1,814 Days
• Field of Search: 702/85, 702/104, 702/105, 702/141, 702/142, 702/145, 701/1, 701/38, 701/70, 701/72, 318/58, 318/61, 318/64, 318/90, 318/259, 318/651, 303/146, 303/147, 180/197
• US Class Current: 702/141
• CPC Class Codes: B60W 40/105 Speed
• CPC Class Codes: B60W 40/107 Longitudinal acceleration
• 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
• CPC Class Codes: B60W 40/12 related to parameters of the vehicle itself , e.g. tyre models
• CPC Class Codes: G01C 9/08 Means for compensating acceleration forces due to movement of instrument
• CPC Class Codes: G01P 15/18 in two or more dimensions

Abstract

To provide an attitude-angle detecting apparatus, which detects an attitude angle of a mobile object during movement with good accuracy by correcting an output value from an acceleration sensor, and to provide a method for the same. It is characterized in that it comprises an acceleration sensor for measuring an acceleration being applied to a mobile object, a yaw-rate sensor for measuring a yaw rate of the mobile object, a speed sensor for measuring a speed of the mobile object, a mobile-component acceleration calculating means for calculating an actual acceleration from the speed, calculating a centrifugal force from the yaw rate and the speed and calculating a mobile-component acceleration, a resultant force of the actual speed and the centrifugal force, and an attitude-angle calculating means for calculating an attitude angle from a gravitational acceleration, which is obtainable by correcting the acceleration with the mobile-component acceleration.

Claims

1. An attitude-angle detecting apparatus comprising:

an acceleration sensor for measuring an acceleration being applied to a mobile object;

a yaw-rate sensor for measuring a yaw rate of the mobile object;

a speed sensor for measuring a speed of the mobile object;

a mobile-component acceleration calculating means comprising;

a front/rear-axis acceleration calculating means for calculating an actual acceleration by differentiating the speed with time, thereby adapting it into a front/rear-axis-direction component force of a mobile-component acceleration;

a right/left-axis acceleration calculating means for calculating a centrifugal force from the yaw rate and the speed, thereby adapting it into a right/left-axis-direction component force of the mobile-component acceleration; and

an up/down-axis acceleration calculating means for calculating a component force of the centrifugal force in the up/down-axis direction of the mobile object, thereby adapting it into an up/down-axis-direction component force of the mobile-component acceleration; and

an attitude-angle calculating means for calculating an attitude angle from a gravitational acceleration, which is obtainable by correcting the acceleration with the mobile-component acceleration.

2. The attitude-angle detecting apparatus set forth in claim 1, wherein said attitude-angle calculating means comprises:

a gravitational-acceleration calculating means for calculating said gravitational acceleration in which said mobile-component acceleration is removed from said acceleration;

a roll-angle calculating means for calculating a roll angle of the mobile object from the gravitational acceleration; and

a pitch-angle calculating means for calculating a pitch angle of the mobile object from the gravitational acceleration.

3. The attitude-angle detecting apparatus set forth in claim 2, wherein:

the calculation of the component force of said centrifugal force at said up/down-axis acceleration calculating means is carried out based on said roll angle or said pitch angle that is calculated by said attitude-angle calculating means; and

the attitude-angle calculating means calculates at least one of the roll angle and the pitch angle based on a component force of the centrifugal force being calculated.

4. An attitude-angle detecting method comprising:

a measuring step of measuring an acceleration being applied to a mobile object, a yaw rate of the mobile object, and a speed of the mobile object;

wherein the acceleration is measured with an acceleration sensor, the yaw rate is measured with a yaw-rate sensor, and the speed is measured with a speed sensor;

a mobile-component acceleration calculating step, performed via a mobile component acceleration calculator, comprising;

a front/rear-axis acceleration calculating step of calculating an actual acceleration by differentiating the speed with time, thereby adapting it into a front/rear-axis-direction component force of a mobile-component acceleration;

a right/left-axis acceleration calculating step of calculating a centrifugal force from the yaw rate and the speed, thereby adapting it into a right/left-axis-direction component force of the mobile-component acceleration; and

an up/down-axis acceleration calculating step of calculating a component force of the centrifugal force in the up/down-axis direction of the mobile object, thereby adapting it into an up/down-axis-direction component force of the mobile-component acceleration; and

an attitude-angle calculating step of calculating an attitude angle from a gravitational acceleration, which is obtained by correcting the acceleration with the mobile-component acceleration,

wherein the attitude-angle calculating is performed via an attitude angle calculator.

5. The attitude-angle detecting method set forth in claim 4, wherein said attitude-angle calculating step comprises:

a gravitational-acceleration calculating step of calculating said gravitational acceleration in which said mobile-component acceleration is removed from said acceleration;

a roll-angle calculating step of calculating a roll angle of the mobile object from the gravitational acceleration; and

a pitch-angle calculating step of calculating a pitch angle of the mobile object from the gravitational acceleration.

6. The attitude-angle detecting method set forth in claim 4, wherein:

said gravitational-acceleration calculating step is a step of calculating said gravitational acceleration while dividing it into front/rear-axis-direction, right/left-axis-direction and up/down-axis-direction component forces, and calculating a part of the respective component forces based on said roll angle or said pitch angle that is calculated at one of said roll-angle calculating step and said pitch-angle calculating step;

one of the roll-angle calculating step and the pitch-angle calculating step is a step of calculating the roll angle or the pitch angle based on a reminder of the respective component forces; and

the other one of the roll-angle calculating step and the pitch-angle calculating step is a step of calculating the roll angle or the pitch angle based on a part of or all of the respective component forces.