Attitude and heading reference detecting apparatus

• US 4,831,544 A
• Filed: 11/17/1987
• Issued: 05/16/1989
• Est. Priority Date: 12/28/1985
• Status: Expired due to Term

• Current Assignee: Tokyo Keiso Company
• Original Assignee: Tokyo Keiso Company
• Inventors: Morohoshi, Mikio, Hame, Fuyuki, Hojo, Takeshi, Yamamoto, Kanshi
• Primary Examiner(s): Blum, Theodore M.
• Assistant Examiner(s): Issing, Gregory C.
• Application Number:
  US07/121,873
• Time in Patent Office: 546 Days
• Field of Search: 364/453, 364/434, 244/3.2, 244/3.21, 73/504, 73/505, 73/178 R
• US Class Current: 701/220
• CPC Class Codes: G01C 21/166 Mechanical, construction or arrangement details of inertial navigation systems
• CPC Class Codes: G01C 21/183 Compensation of inertial measurements, e.g. for temperature effects

Abstract

An attitude and heading reference detecting apparatus having three gyros and three acceleometers mounted to a navigation vehicle in such a manner that their input axes are made coincident with principal three axial directions of the navigation object, respectively, a magnetic azimuth sensor, a signal transforming section supplied with the outputs from the three gyros, the outputs from the three accelerometers and the output from the magnetic azimuth sensor, a computing section supplied with the output from the signal transforming section and a signal output section supplied with the output from the computing section, for producing an attitude and heading reference signal and for delivering the same to the outside.

Claims

1. Attitude and heading reference detecting apparatus comprising:

(a) three gyros and three accelerometers mounted on a navigation vehicle in such a manner that their input axes are respectively made coincident with the principal three axial directions of said navigation vehicle;

(b) a magnetic azimuth sensor;

(c) a signal transforming section supplied with outputs from said three gyros, outputs from said three accelerometers and an output from said magnetic azimuth sensor;

(d) a computing section supplied with an output from said signal transforming section; and

(e) a signal output section supplied with an output from said computing section for producing an attitude and heading reference signal and for delivering the same to an outside terminal, wherein said computing section comprises a CTM (coordinate transforming matrix) computing section for receiving the gyro signals from said three gyros, a horizontal component computing section for calculating horizontal components of gravity from a CTM signals from said three accelerometers, an erecting torque computing section supplied with an output from said horizontal component computing section and for computing a CTM erecting torque signal, an azimuth slaving torque computing section for comparing an azimuth signal from said CTM computing section and a magnetic azimuth signal from said magnetic azimuth sensor and for computing an azimuth slaving torque signal which causes said CTM to be restricted to said magnetic azimuth signal around said azimuth axis, wherein said erecting torque signal and said azimuth slaving torque signal are fed back to said CTM computing section, and said computing section further includes a gyro bias computing section which is supplied with said erecting torque signs, said azimuth slaving torque signal and said CTM signal for computing a gyro bias, and said three gyro bias correctors are further supplied with an output from said gyro bias computing section and produce rate outputs.

2. Attitude and heading reference detecting apparatus according to claim 1, wherein said gyro bias computing section is an observer.

3. Attitude and heading reference detecting apparatus according to claim 1, wherein said magnetic azimuth sensor has a magnetic azimuth detecting section directly mounted to said navigation vehicle.

4. Attitude and heading reference detecting apparatus according to claim 3, further comprising an inclination error correcting and computing section provided in said computing section for correcting an error caused by the inclination of said magnetic azimuth sensor.