Navigation Functionalities for an Autonomous UAV Helicopter

Chapter 4
Path Following Control
Mode
4.1 Introduction
The PFCM described in this chapter and presented in Paper I, has been
designed to navigate an autonomous helicopter in an area cluttered with
obstacles, such as an urban environment. In this thesis, the path planning
problem is not addressed although it is in [18]. It is assumed that a
path planning functionality generates a collision-free path. Then the task
which will be solved here is to find a suitable guidance and control law
which enables the helicopter to follow the path robustly. The path planner
calculates the geometry of the path that the helicopter has to follow. A
geometric path segment, represented by a set of parameters, is then input
to the PFCM.
Before starting with the description of the PFCM, some basic terminology
will be provided.
The guidance is the process of directing the movements of an aeronautical
vehicle with particular reference to the selection of a flight path.
The term of guidance or trajectory generation in this thesis addresses the
problem of generating the desired reference position and velocity for the
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