Angular velocity measuring device and leg-moving robot

• US 20070152618A1
• Filed: 07/13/2005
• Published: 07/05/2007
• Est. Priority Date: 07/22/2004
• Status: Active Grant

• Current Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Original Assignee: Honda Motor Co., Ltd. (Honda Motor Company)
• Inventors: Saika, Hitoshi, Akahori, Shigeto, Hirayama, Shinyu, Hori, Kengo, Shimada, Yoichi, Okamoto, Noriaki, Sakogoshi, Tomohiro, Saotome, Kouji
• Granted Patent: US 7,292,000 B2
• Time in Patent Office: Days
• US Class Current: 318/568.120
• CPC Class Codes: B25J 13/088 with position, velocity or acceleration sensors
• CPC Class Codes: G01C 19/005 Measuring angular rate using gyroscopic effects
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: G01C 19/5776 Signal processing not specific to any of the devices covered by groups G01C19/5607 - G01C19/5719

Abstract

An angular velocity measuring device (1) includes a first sensor (2) (vibratory gyroscope) and a second sensor (3) (gas rate gyroscope). A detected output of the first sensor (2) is input to a highpass filter (4) and an output of this filter (4) is stored in the time series into a memory (10). Subtraction means (11) sequentially performs operations of subtracting an output ωv′(t−tsd) of the filter (4) at a time a predetermined time period tsd earlier from an output ωv′(t) of the filter (4), and addition means (12) sequentially adds the value obtained by the above to an output ωg(t) of the second sensor (3), whereby an angular velocity measurement is obtained. Thereby, it is possible to provide an angular velocity measuring device whose angular velocity measurements are high in response and stability at a low price.

Claims

1. An angular velocity measuring device comprising:

a first sensor for generating a detected output of an angular velocity;

a second sensor for generating a detected output of an angular velocity with lower drift of the detected output than in the first sensor;

a high-frequency pass filter for being inputted the detected output of the first sensor and outputting higher frequency components than a predetermined frequency in the detected output;

storage means for sequentially storing output values of the high-frequency pass filter;

subtraction means for sequentially performing operations of subtracting an output value at a time a predetermined time period earlier, which is stored in the storage means, from the output value of the high-frequency pass filter; and

addition means for sequentially performing operations of adding a value obtained by the subtraction means to the output value of the second sensor, wherein a value obtained by the addition means is obtained as an angular velocity measurement.

2. The angular velocity measuring device according to claim 1, wherein the first sensor has an output characteristic of a shorter delay in response of the detected output to a change in the angular velocity than in the second sensor and the predetermined time period is set to a time period according to a difference between a delay in response of the first sensor and a delay in response of the second sensor.

3. The angular velocity measuring device according to claim 1, wherein the first sensor is a vibratory gyroscope and the second sensor is a gas rate gyroscope.

4. A leg-moving robot comprising:

two legs extending from an upper body;

an angular velocity measuring device, which includes;

a first sensor for generating a detected output of an angular velocity;

a second sensor for generating a detected output of an angular velocity with lower drift of the detected output than in the first sensor;

a high-frequency pass filter for receiving an input of the detected output of the first sensor and outputting higher frequency components than a predetermined frequency in the detected output;

storage means for sequentially storing output values of the high-frequency pass filter;

subtraction means for sequentially performing operations of subtracting an output value at a time a predetermined time period earlier, which is stored in the storage means, from the output value of the high-frequency pass filter; and

addition means for sequentially performing operations of adding a value obtained by the subtraction means to the output value of the second sensor, wherein a value obtained by the addition means is obtained as an angular velocity measurement;

posture angle estimation means for estimating a posture angle of a predetermined portion at least on the basis of the angular velocity measurement obtained by the angular velocity measuring device; and

control means for generating a joint drive command signal of the robot at least on the basis of the posture angle estimated by the posture angle estimation means,

wherein a joint actuator for driving the joint of the robot is activated according to the joint drive command signal.

5. The leg-moving robot according to claim 4, further comprising an acceleration sensor for measuring accelerations including a gravitational acceleration acting on the robot, wherein the posture angle estimation means estimates the posture angle of the predetermined portion on the basis of the angular velocity measurement obtained by the angular velocity measuring device and the acceleration measurement obtained by the acceleration sensor.