TABLE OF CONTENTS Navigation is a very ancient skill or art which has become a complex science. It is essentially about travel and finding the way from one place to another and there are a variety of means by which this may be achieved [1].
Perhaps one of the simplest forms of navigation is the following of directions, or instructions. For example, a person wishing to travel to a given destination from where they are at the moment may be instructed: turn right at the next junction, turn left at the 'Rose and Crown', keep to the right of a given landmark, ..., it will be in front of you! Clearly, this method of navigation relies on the observation and recognition of known features or fixed objects in our surroundings and moving between them. In technical narratives, the locations of these features are often referred to as 'way-points'.
An extension of this process is navigation by following a map. In this case, the navigator will determine his or her position by observation of geographical features such as roads, rivers, hills and valleys which are shown on the map. These features may be defined on the map with respect to a grid system or 'reference frame'. For example, positions of terrain features are often defined with respect to the Earth's Equator and the Greenwich meridian by their latitude and longitude. Hence the navigator is able to determine his or her position in that reference frame. As will become clear later in the...
