Moving body with tilt angle estimating mechanism

• US 8,000,925 B2
• Filed: 09/27/2007
• Issued: 08/16/2011
• Est. Priority Date: 10/05/2006
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Fuwa, Toshio, Nakashima, Issei
• Primary Examiner(s): Dunn; Drew A
• Assistant Examiner(s): Cherry; Stephen
• Application Number:
  US12/297,323
• Publication Number:
  US 20090138232A1
• Time in Patent Office: 1,419 Days
• Field of Search: 702150-154
• US Class Current: 702/154
• CPC Class Codes: G01B 21/22 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: G01C 9/06 Electric or photoelectric indication or reading means

Abstract

A moving body with a tilt angle estimating mechanism capable of estimating a tilt angle of a vehicle body with high accuracy. The moving body includes: an acceleration sensor for detecting an acceleration in two axial directions; a gyro sensor for detecting an angular velocity of a vehicle body; and a tilt angle estimating mechanism for estimating a tilt angle of the vehicle body. The tilt angle estimating mechanism includes: a device for estimating a tilt angle in response to the acceleration sensor based on the acceleration detected by the acceleration sensor; a device for estimating a second tilt angle based on the angular velocity detected by the gyro sensor; and a device for estimating a tilt angle with a linear model equation of the moving body being regarded as an observer, in accordance with the tilt angle based on the acceleration sensor and the tilt angle based on the gyro sensor.

Claims

1. A moving body, comprising:

an acceleration sensor for detecting an acceleration in two axial directions;

a gyro sensor for detecting an angular velocity of a vehicle body; and

a tilt angle estimating mechanism for estimating a tilt angle of the vehicle body,

wherein the tilt angle estimating mechanism includes;

a device for estimating a first tilt angle based on the acceleration detected by the acceleration sensor;

a device for estimating a second tilt angle based on the angular velocity detected by the gyro sensor according to a linear model equation of the moving body; and

a device for estimating a tilt angle by executing feedback control so that the second tilt angle follows the first tilt angle, with the first tilt angle being set as a reference value for an observer, wherein the moving body is an inverted two-wheeled vehicle and the feedback control is at least in part based on an external force observer that uses a value of an external force as a state quantity.

2. The moving body according to claim 1, wherein the tilt angle estimating mechanism includes a setting device for setting an observer gain K for adjusting an effect of the first tilt angle, to an arbitrary value.

3. The moving body according to claim 2, wherein the setting device sets the observer gain K to a small value when the moving body is in a longitudinal acceleration state.

4. The moving body according to claim 2, wherein the setting device sets the observer gain K according to a failure condition of each of the acceleration sensor and the gyro sensor.

5. The moving body according to claim 1, wherein the acceleration sensor includes a low-pass filter provided in a subsequent stage thereof.

6. A moving body, comprising:

an acceleration sensor detecting an acceleration in two axial directions;

a gyro sensor detecting an angular velocity of a vehicle body; and

a tilt angle estimating mechanism estimating a tilt angle of the vehicle body,

wherein the tilt angle estimating mechanism includes;

a first estimation portion estimating a first tilt angle based on the acceleration detected by the acceleration sensor;

a second estimation portion estimating a second tilt angle based on the angular velocity detected by the gyro sensor according to a linear model equation of the moving body; and

a third estimation portion estimating a tilt angle by executing feedback control so that the second tilt angle follows the first tilt angle, with the first tilt angle being set as a reference value for an observer,

wherein the moving body is an inverted two-wheeled vehicle and the feedback control is at least in part based on an external force observer that estimates a value of an external force as a state quantity.