Design and Implementation of a High-Precision 6-DOF Inertial Measurement Unit for Unmanned Vehicles

• Main Authors: Jyun-lin Peng, 彭俊霖
• Other Authors: Juhng-Perng Su
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/39757938035348313846

碩士 === 國立雲林科技大學 === 電機工程系碩士班 === 95 === Recently, the micro inertial sensors have become cost effective than ever due to the maturity of Micro Electro-Mechanical System (MEMS) technologies. This thesis devotes to develop a low-cost inertia measurement unit which provides dynamic feedback signals of attitude for flight control of an autonomous Unmanned Aerial Helicopters (UAH) including the three-axis accelerations, velocities, and the corresponding pitch, roll, yaw angles and angle rates with heading of UAH. The measurement unit consists of three-axis magnetometers, three-axis gyroscopes and three-axis accelerometers which are strapped and deployed on the airframe, termed strap-down installation. Due to the drift and bias of sensors, the attitude and the axis velocities suffer from the accumulated errors arising from the integration and coordinate transformations and thus, in general, cannot be used in the long run. In order to increase the reliability, filters are used as integrators to do the estimations of attitude angles and axis velocities. In addition, an angle error correction algorithm and a moving averaging estimator have been employed to reduce the accumulation errors for improving the long-term accuracy. The filter has the merits of performing reliable state estimation and noise reduction. The core computation module is a Digital Signal Processor (DSP) equipped with some Analog/Digital (A/D) and communication modules. Inertial rate gyros and axis accelerations are incorporated and integrated into the DSP module to form an inertia measurement unit. To evaluate its performance, a linear motion cart and a two-axis tilt-controlled plate are employed to justify the accuracies of accelerations and attitude angles.