Inertial reference unit

About: Inertial reference unit is a research topic. Over the lifetime, 1306 publications have been published within this topic receiving 22068 citations. The topic is also known as: IRU.

Method and system for validating an inertial unit of a mobile object

Abstract: The method involves obtaining measured inertial data (R) produced by an inertial unit (3) by an obtaining unit, and theoretically modeling the measured inertial data from kinematics data by a theoretical modeling unit for providing theoretical inertial data (T1). A theoretical modeling distort error of the measured inertial data is compensated before the theoretical modeling process. A controlling command (P) is calculated from the measured inertial data, theoretical inertial data and simulation inertial data (T2). An independent claim is also included for a system for validating an inertial platform of a moving craft on a motion simulator, comprising a theoretical model.

Novel two position ground alignment technique for Strapdown Inertial Navigation System

Abstract: The paper describes a novel two position alignment procedure on ground for Strapdown Inertial Navigation System. The method makes use of accelerometers and gyroscopes measurements from a standalone INS without any external aiding to obtain higher accuracy of heading angle. This technique mitigates the effect of down-gyroscope bias by solving simultaneous equations for the determination of azimuth. The accuracy is further improved by implementing a linear search to correct the azimuth dithered by the presence of gyroscope bias. The supporting simulation and experimental results are presented. The algorithm can be used in launch vehicle applications where there is a need for higher accuracy of azimuth prior to launch.

System for the transfer of alignment between the inertial system of a carried vehicle and that of the carrier vehicle

Abstract: System permitting, for example, initialisation of the inertial unit (CNm) of a missile from the inertial unit (CNp) of the carrier of this missile. According to the invention, a servo control device (A) is provided for the data from the inertial unit of the carrier (CNp) in the inertial unit (CNm) of the missile and a Kalman filter (K) is provided, mounted in parallel on the said servo control device (A) and intended to identify the harmonisation errors between the two inertial units.

Inertial attitude control of Voyager spacecraft using dry tuned rotor gyro

Abstract: The inertial attitude control system designed for the Voyager spacecraft, which will carry out flybys of Jupiter and Saturn in 1979 and 1981, respectively, is described. The attitude of the spacecraft in three-dimensional space will be measured by a Dry Inertial Reference Unit (DIRU) based on three identical two-degree-of-freedom dry gyros. A software estimation process has been developed to use DIRU data and other information to obtain optimum estimates of spacecraft position, velocity, and acceleration. The attitude of the spacecraft is corrected using these estimates by activating hydrazine thrusters. The operation of dry gyros is discussed, together with the network compensation techniques used in their associated capture loop to obtain a capture capability of 8 deg/sec and a frequency response of 10 Hz (3-dB point). The control law and estimation process are examined. Results of computer simulation studies of the performance of the attitude control system are presented.