In the last decade, signi?cant changes have occurred in the ?eld of vehicle motion planning, and for UAVs in particular. UAV motion planning is especially dif?cult due to several complexities not considered by earlier planning strategies: the - creased importance of differential constraints, atmospheric turbulence which makes it impossible to follow a pre-computed plan precisely, uncertainty in the vehicle state, and limited knowledge about the environment due to limited sensor capabilities. These differences have motivated the increased use of feedback and other control engineering techniques for motion planning. The lack of exact algorithms for these problems and dif?culty inherent in characterizing approximation algorithms makes it impractical to determine algorithm time complexity, completeness, and even soundness. This gap has not yet been addressed by statistical characterization of experimental performance of algorithms and benchmarking. Because of this overall lack of knowledge, it is dif?cult to design a guidance system, let alone choose the algorithm. Throughout this paper we keep in mind some of the general characteristics and requirements pertaining to UAVs. A UAV is typically modeled as having velocity and acceleration constraints (and potentially the higher-order differential constraints associated with the equations of motion), and the objective is to guide the vehicle towards a goal through an obstacle ?eld. A UAV guidance problem is typically characterized by a three-dimensional problem space, limited information about the environment, on-board sensors with limited range, speed and acceleration constraints, and uncertainty in vehicle state and sensor data.

This book contains peer reviewed paper reprints from the 2nd International Symposium on Unmanned Aerial Vehicles, June 2009. It covers the latest advances in Unmanned Aircraft Systems (UAS) Modeling, Control and Identification; UAS Navigation, Path Planning and Tracking; UAS Vision and Vision-Based Systems; UAS Landing and Forced Landing; Simulation Platforms and Testbeds; and UAS Applications.

The volume brings together the latest research findings from the rapidly evolving and expanding area of UAS, along with current technical challenges and future needs that need be overcome in order to utilize fully unmanned aviation in civilian/public domain applications.

This work is suitable for the researcher and scientist, the practitioner, the novice and the UAV user. It may also serve as a reference text for graduate level special topic courses in UAVs.

Also published in the Journal of Intelligent and Robotic Systems, Volume 57, Issues 1-4, 2010.