Principles of GNSS, Inertial, and Multi-sensor Integrated Navigation Systems

Citation

Budiyono, A. (2012), "Principles of GNSS, Inertial, and Multi-sensor Integrated Navigation Systems", Industrial Robot, Vol. 39 No. 3. https://doi.org/10.1108/ir.2012.04939caa.011

Principles of GNSS, Inertial, and Multi-sensor Integrated Navigation Systems

Article Type: Book review From: Industrial Robot: An International Journal, Volume 39, Issue 3

Paul D. GrovesArtech House2007540 pp.$129ISBN 978-1-58053-255-6Web Link: www.artechhouse.com/Principles-of-GNSS-Inertial-and-Multisensor-Integrated-Navigation-Systems/b/1295.aspx

The book is divided into four parts and two appendices. The first part is a chapter of introduction of the subject. The second part contains two chapters, each about the mathematics of navigation science and estimation algorithm – the Kalman filter. The third part consists of eight chapters, describing various navigation technologies ever developed. The last part is about the integration of different navigation technologies, and system integrity monitoring. The two appendices provide quick summaries about vector and matrix algebra, and about statistics.

Chapter 1 presents the basic concepts of navigation and provides a qualitative overview of the book’s material. It also presents a comparison among navigation technologies and puts contemporary navigation techniques in historical context. Chapter 2 presents the mathematical foundations that the principles of navigation concepts are based on. It discusses the concept of coordinate frame and how it is used to represent an object, reference, or set of resolving axes. Chapter 3 provides an introduction to the Kalman filter and a review of its practical use in navigation application.

Chapter 4 presents a review about inertial sensors, describing the basic principles of various types of accelerometers and gyros, IMU, and a review about their errors. It discusses error characteristics exhibited by accelerators and gyroscopes. Chapter 5 presents discussions about what happens in inertial navigation process, which basically consists of four steps: attitude update, specific force transformation, velocity update, and position update. The navigation process discussed in this chapter is formulated in Earth-centered inertial frame, Earth-centered Earth-fixed frame, and local navigational frame along with wander azimuth frame.

Chapter 6 presents an introduction to satellite navigation. The different terminology used for various satellite navigation systems in literature is described, and which terminology used in this book is clearly stated. Chapter 7 presents thedescription of how GNSS user equipment processes navigational signals from the satellites to obtain ranging measurements and a navigation solution. The geometry of the navigation signals is described, following the fundamental concepts of satellite navigation introduced in the previous chapter. This chapter also reviews the error sources.

Chapter 8 presents a number of methods to enhance the GNSS’ accuracy, robustness, and reliability. It covers techniques of carrier phase tracking to obtain high precision position and attitude measurements under good conditions. The chapter describes several techniques for improving GNSS robustness and multipath mitigation under difficult conditions. Chapter 9 describes the terrestrial radio navigation systems. The first section describes how point-source systems work. These short-range navigation systems include non-directional beacons (NDBs), very high frequency (VHF) omni-directional radio range (VOR), and distance measuring equipment (DME). Chapter 10 presents methods of positioning using dead reckoning techniques other than inertial navigation. These methods generally use measurements of user motion with respect to the environment without the need for radio signals or the extensive environment’s feature database.

Chapter 11 describes feature matching algorithms, and presents them in four sections. The first section describes terrain-referenced navigation (TRN). The following section discusses three feature matching navigation techniques called stellar navigation, gravity gradiometry, and magnetic field variation. In gravity gradiometry, position solution is determined by observing gravitational contour over a spatial region and comparing it with that of a database. Similar to that of gravity gradiometry, in the magnetic field variation technique, the feature being observed is magnetic contour, compared with that of a global geomagnetic field database.

Chapter 12 discusses the integration between INS and GNSS. It begins with a summary about INS’ and GNSS’ characteristics, and the general idea and motivation of the integration. This chapter describes different integration architectures and discusses the comparison among them. These integration architectures are described in each respective subsection: GNSS-corrected inertial navigation solution, loosely-coupled integration, tightly-coupled integration, GNSS acquisition and tracking aiding, and deep integration. Chapter 13 discusses a number of calibration and alignment methods to improve INS attitude solution. This chapter follows on the discussion about INS initialization and alignment in Chapter 5, and INS/GNSS integration in Chapter 12.

Chapter 14 discusses the multi-sensor navigation system. It describes how INS and GNSS may further be integrated with other navigation systems such as terrestrial radio navigation systems, dead reckoning, and feature matching navigation systems. Summaries on different combinations of navigation sensor systems for different vehicles and applications are presented. Chapter 15 discusses integrity monitoring systems in navigation systems. It focuses its discussions on user-based monitoring approaches. Levels of the monitoring system are described: fault detection (FD), fault detection and recovery (FDR), fault detection and isolation (FDI), fault detection and exclusion (FDE).

Assessment

Throughout the book, problems commonly shared by most science book and engineering book authors, notation/terminology consistency, often appears. The author is well aware of this problem. Therefore, whenever a discussion involves terminologies that are sometimes used differently in other literatures, he always states clearly which ones are to be used in the book. All notations and terminologies are sorted in a list, including the conflicting ones. Some of the conflicting notations can be easily sorted out by context, but there are some notations that cannot be clarified by context. It would be better if all notations are listed per chapter as are the references. However, there is one troubling issue about the meaning of “>” shown in Figure 2.7. The “>” notation is widely used to represent the phrase “being greater than”. It seems the author has it for another meaning, which from the context suggests, as “being transformed to”. No matter how strong the context suggests what the “>” represents, it is still hard to accept the “>” notation to represent a meaning other than “being greater than”. Moreover, there is no explicit explanation about this. Therefore, the use of “>” in this case is misleading.

As far as the book title is concerned, the core content of the book begins from Chapter 4 forward, while the first three chapters could either be compressed into one single chapter or presented as appendices, since the nature of their content is only as an introduction (Chapter 1) and can be treated as reference material (Chapter 2 and 3). Nevertheless, they are placed at the beginning of the whole content. This reflects the author’s concern about the importance of these chapters to provide required knowledge for readers with no prior knowledge about navigation before proceeding further with the following chapters. From the whole content it presents, the book is complete as a source literature for scientists, engineers, students, or general readers in the subject. For this matter, the book has fulfilled its purpose as stated by the author in the book’s preface.

Agus BudiyonoDepartment of Aerospace Information Engineering, Konkuk University, Seoul, Korea