Strapdown inertial navigation technology - 2nd edition - [Book review

Abstract

Anyone exercising outdoor activities as scouting, hunting, or wildlife photographing -not to mention walking in the city -plus those of us engaged with defense activities can state it is more convenient to get lost if one knows where this happens. Perhaps this is one of the key reasons why methods and technologies for navigation have been an area of continuing efforts and interest.After the introduction of fast moving vehicles, and later when defensive or hostile weapons came into use, it was not sufficient to know where the platform was located but it was really vital to be aware of its momentary alignment, of course, in a three dimensional space. New challenges were put to the shoulders of the navigator. When time, equipment. and location allow, navigation relying on external references such as radio beacons on ground or up in the space orbits are often preferred. However, such cooperative systems may not be available, or their performance is inadequate for the short time constants of platform motion. We are thus forced to use autonomous navigation modes. It is here that inertial navigation systems have. for long, been the way to go. First, we had simple gimbals, the mechanical spinning gyroscopes and later came fiber optic laser devices. "Strapdown Inertial Navigation Technology" by Prof.David Titterton and Dr. John Weston is a new entry to this complicated field. surely of interest to many Systems readers.A brief quantitative study of this boo k indicates 558 relatively dense-packed pages containing 15 chapters, four appendices. an alphabetical Index of some 1000 words and a List of Symbols. The size of individual chapters varies from less than about ten pages to over 60. Line drawings (bQth graphic presentations of functions and pictures of equipment constructions) and photographs are extensively used so that their total number is roughly 250.Unavoidably a book about navigation gets mathematical in nature and here the amount of equations is close to 390. Matrices, vectors, and integrals are needed constantly. The authors have not followed a strict logic in the internal arrangement. This can be seen in the treatment of tables. The first half of "Strapdown Inertial Navigation Technology" has many tables without any numbering, just data and headings placed in small rectangular boxes. However, later the authors have selected conventional numbering and have discarded frames. Due to this, we are unable to give any value for the amount of tabulated information. Most publishers seem to prefer references placed after each chapter.

Autonomous Aerial Surveillance System Movement Monitoring by Using Strap-Down Inertial Techniques

“…Once determined the spatial coordinates of the vehicle relative to NED frame, will resort to their conversion into geodetic coordinates. Switching between NED and SG is not done directly, but involves an intermediate conversion in ECEF frame ( [7], [12], [13]). For the vehicle attitude determination the literature provides two equivalent parametrizations, quaternionic and matriceal, but at the final both of them estimate the SV to NED transformation matrix .…”

“…After this preliminary step, the designer should establish the reference frames implied in the evaluation of the solution of navigation provided to the user. Considering the navigation requirements imposed by our aerial systems, our team chosen as needed reference frame the next ones ( [7], [12]): 1) EarthCentered-Earth-Fixed (ECEF) frame (OX (Fig. 3 [12]).…”

Heading Measurements for Indoor Mobile Robots with Minimized Drift Using a MEMS Gyroscopes

“…The output of gyro has rather complex noise characteristics that are produced by many different error sources. A detailed general model and a thorough discussion on each individual error component can be found for instance in (Titterton & Weston, 2004) Figure 2, gyro errors are subdivided into two main categories according to their spectral signature: errors that change rather rapidly (short-term) and rather slowly (long-term). The characteristics of two different categories can be analyzed through an Allan-variance chart.…”

Design and implementation of dynamic simulators for the testing of inertial sensors

“…This activity is part of the COINS project undertaken by the MDM Lab, the Laboratory of Mechatronics and Dynamic Modelling of the University of Florence: the main goal of this project is the development of an innovative localization system based on the integration of odometers and an Inertial Measurement Unit (IMU) [3]: the result of the project will be a commercial industrial product to be used in Automatic Train Protection This work has been supported by ECM S.p.A. within the project COINS (Cooperative Odometry-Inertial Navigations System), funded by Regione Toscana under the program " BANDO and Control (ATP/ATC) systems in order to increase the reliability and security of the railway traffic. Since the safety and the efficiency of these systems is strongly influenced by the precision of the estimate of speed and distance travelled, the objective is to increase the accuracy of the motion estimates, especially in degraded adhesion conditions, through the implementation of INS (Inertial Navigation System) [4], [5]. The IMU has been expressly designed and realized to comply with the COINS project requirements.…”