A High Accuracy Hybrid Navigation System for Unmanned Underwater Vehicle

Hideo Kumagai, Masato Kihara, Yukihiro Kubo and Sueo Sugimoto

Abstract:	The development of small, light weight, low power navigation systems for guidance of both tethered and autonomous Unmanned Underwater Vehicle (UUV) is for required in applications such as deep salvage, oil and gas well head and pipe line laying and maintenance, sea bed mining, communication cable laying and maintenance, and scientific surveys. All have stringent position requirements in order to define target locations followings the initial find minimize search time for return missions, as well as support of autopilot functions (attitude and/or heading control). In these applications mainly an accurate Sonar Doppler Velocity Log (DVL) was used for the INS error corrections [1,2]. But the settlement of DVL is not affordable to various UUV so that not convenient to low cost and small UUV. Furthermore it is very expensive for commercial use. In this paper we propose a new algorithm for combining the low cost but highly accurate inertial Navigation System (INS) with the Water Screw Speed (WSS) of the UUV efficiently. Usually in this kind of hybrid system, the system estimates the errors (attitude/heading, velocity, position, gyro bias, accelerometer bias) of INS by the Kalman filter applying the WSS information as the measurement. But due to existence of the Water Current and the WSS slip there are some unexpected errors in the measurement such that these errors degrade the estimation accuracy, especially, position errors. For improving the degradation we introduce the concept which estimates the Water Current and WSS slip simultaneously using the Kalman filter. And in order to evaluate our algorithm we produced the data acquisition system containing the INS (composed of Ring Laser Gyro and Accelerometer) and the Vehicle Motion Sensor (VMS), settled in the experimental VAN. Especially the INS was settled whose orthogonal coordinate is slightly different to the direction of VAN frame in order to simulate the Water Current input. And the reference position data were obtained by transferred differential GPS simultaneously. After several experimental run, we simulated this algorithm searching the correlation time and noise variance of estimations.
Published in:	Proceedings of the 57th Annual Meeting of The Institute of Navigation (2001) June 11 - 13, 2001 Albuquerque, NM
Pages:	356 - 363
Cite this article:	Kumagai, Hideo, Kihara, Masato, Kubo, Yukihiro, Sugimoto, Sueo, "A High Accuracy Hybrid Navigation System for Unmanned Underwater Vehicle," Proceedings of the 57th Annual Meeting of The Institute of Navigation (2001), Albuquerque, NM, June 2001, pp. 356-363.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In