Method of estimating mounting angle error of gyroscopes by using a turning device, and corresponding turning device

Patent metadata

Field	Value
Publication number	US-9321498-B2
Application number	US-201214361978-A
Country	US
Kind code	B2
Filing date	Nov 29, 2012
Priority date	Dec 2, 2011
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

Bias values of pitch axis and roll axis angular velocity sensors in a stationary state where a reference yaw axis of a two-wheeled inverted pendulum vehicle body is stationary in parallel with a vertical direction are acquired. Bias values of the pitch axis and roll axis angular velocity sensors in a turning state where a two-wheeled inverted pendulum vehicle is turned at a predetermined turning angular velocity in a state where the reference yaw axis of the two-wheeled inverted pendulum vehicle body remains parallel to the vertical direction are acquired. Mounting angle errors of the pitch axis and roll axis angular velocity sensors with respect to the two-wheeled inverted pendulum vehicle body are estimated on the basis of the bias values of the sensors in the stationary state, the bias values of the sensors in the turning state and the predetermined turning angular velocity.

First claim

The invention claimed is:

1. A method of estimating, in an inverted pendulum mobile unit that includes an inverted pendulum mobile unit body, a pitch axis angular velocity sensor, a roll axis angular velocity sensor and at least one central processing unit, a mounting angle error of the pitch axis angular velocity sensor and a mounting angle error of the roll axis angular velocity sensor with respect to the inverted pendulum mobile unit body, the method comprising:
acquiring, by the central processing unit, a first angular pitch axis angular velocity and a first roll axis angular velocity respectively from the pitch axis angular velocity sensor and the roll axis angular velocity sensor in a stationary state where a reference yaw axis of the inverted pendulum mobile unit body is stationary in a vertical direction;
acquiring, by the central processing unit, a second angular pitch axis angular velocity and a second roll axis angular velocity respectively from the pitch axis angular velocity sensor and the roll axis angular velocity sensor in a turning state where the inverted pendulum mobile unit is turned at a predetermined turning angular velocity in a state where the reference yaw axis of the inverted pendulum mobile unit body remains parallel to the vertical direction; and
estimating, by the central processing unit, the mounting angle error of the pitch axis angular velocity sensor and the mounting angle error of the roll axis angular velocity sensor with respect to the inverted pendulum mobile unit body based on the first angular pitch axis angular velocity, the first roll axis angular velocity, the second angular pitch axis angular velocity, the second roll axis angular velocity and the predetermined turning angular velocity.

2. The method according to claim 1 , wherein
in the turning state, the mobile unit body is turned on the spot while being held horizontally.

3. The method according to claim 2 , wherein
the inverted pendulum mobile unit is turned on a pivot in an inverted state.

4. The method according to claim 2 , wherein
the inverted pendulum mobile unit is turned on a pivot on a rotary jig of a turning device,
the turning device includes: a support base that supports the inverted pendulum mobile unit; a plurality of support legs that are adjustable in height and that are connected to the support base; and the rotary jig,
the rotary jig includes a first member connected to the support base and a second member connected to the inverted pendulum mobile unit body,
the first member is coupled to the second member such that the first member is rotatable in parallel with the support base.

5. The turning device used in the method according to claim 2 , comprising:
a support base configured to support the inverted pendulum mobile unit;
a plurality of support legs that are adjustable in height and that are connected to a lower surface of the support base; and
a rotary jig that includes a first member and a second member, wherein
the first member is connected to an upper surface of the support base,
the second member is positioned over the first member,
an upper surface of the second member is connected to the inverted pendulum mobile unit body, and
the first member is coupled to the second member such that the first member is rotatable in parallel with the support base.

6. The method according to claim 1 , wherein
in the stationary state, an output from the pitch axis angular velocity sensor and the output from the roll axis angular velocity sensor each are averaged for a predetermined period of time or longer by the central processing unit.

7. The method according to claim 1 , wherein
in the turning state, an output from the pitch axis angular velocity sensor and the output from the roll axis angular velocity sensor each are averaged for a predetermined period of time or longer by the central processing unit.

8. The method according to claim 1 , wherein
the mounting angle error of the pitch axis angular velocity sensor and the mounting angle error of the roll axis angular velocity sensor are estimated by the central processing unit based on following expressions:

β

0
⁢

⁢
α

=

sin

-
1

⁡

(

α
.

1

-

α
.

0

γ
^

1

)

α

0
⁢

⁢
β

=

sin

-
1

⁡

(

-

β
.

1

-

β
.

0

γ
^

1

)

wherein α 0β indicates the mounting angle error of the roll axis angular velocity sensor with respect to a pitch angle,
β 0α , indicates the mounting angle error of the pitch axis angular velocity sensor with respect to a roll angle,
α 0 indicates the first roll axis angular velocity,
β 0 indicates the first angular pitch axis angular velocity,
α 1 indicates the second roll axis angular velocity,
β 1 indicates the second angular pitch axis angular velocity, and
γ 1 indicates the predetermined turning angular velocity.

9. A turning device comprising:
a support base that is configured to support an inverted pendulum mobile unit;
a plurality of support legs that are adjustable in height and that are connected to a lower surface of the support base; and
a rotary jig that includes a first member and a second member, wherein
the first member is connected to an upper surf

Assignees

• Oikawa Susumu
• Toyota Motor Co Ltd

Inventors

• Oikawa Susumu

Classifications

• B62J45/4152

  for sensing longitudinal inclination of the cycle · CPC title

• B62K11/007 Primary

  Automatic balancing machines with single main ground engaging wheel or coaxial wheels supporting a rider · CPC title

• G01C25/005

  initial alignment, calibration or starting-up of inertial devices · CPC title

• G01C21/18 Primary

  Stabilised platforms, e.g. by gyroscope · CPC title

• G05D1/0891

  specially adapted for land vehicles · CPC title