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There is a pressing operational requirement to migrate Unmanned Aerial Vehicles (UAVs) outside the confines of segregated airspace. The Sense and Avoid capacity is one of the key elements to open the access to airspace for UAVs Referred to layered model of the airspace surrounding the UAV; a collision avoidance method for use in UAVs in nonsegregated airspace is outlined. As to the sense problem, the neighboring vehicles are supposed to exchange their dynamics through the ADS-B system at each sample time to predict the conflicts. Layered zones around the UAV are defined corresponding with hierarchical alarm levels. Dynamic alerting thresholds contribute to reducing fake alarms and neglected alarms by calculating the alerting thresholds based on relative position, azimuth and speed of two aircrafts. The detail algorithm of deriving dynamic alerting thresholds based on the UAV local reference frame is illustrated. Aiming at modifying the algorithm for head-on and tail-chase encounters, right-of-way rules as the maneuver logic are considered in the study. In the simulation, two encounter scenarios were modeled including an intruder with a level flight path intersection, another intruder climbing towards the UAV. Our simulation shows that different guidance advisory associated with hierarchical alarm levels can be real-time presented to ensure separation and avoid collision.

Quadrotor UAVs have attracted significant research interests in recent years, especially their ability of fast and precise maneuvers in constrained environments. Nevertheless, when analysizing the kinematic motion of a quadrotor UAV, most literatures describe the rotation and translation separately. Those modeling methods will limit the maneuverability and control accuracy. This paper first introduces dual quaternion which is a novel and compact mathematical tool to provide an efficient global transformation for the integrated translation and rotation maneuver missions. Then the dynamic model is obtained by the Lagrangian formulation. This integrated modeling method will make the quadrotor UAV achieve higher maneuverability, which is of utmost importance for maneuver missions.

Oblique cross quadrotors vehicle is a variant of quadrotors, which is more suitable for take photos in the air compared to the conventional cross-shaped quadrotors and the rotary-wing state of Quad Tilt Rotor(QTR) have to take this flight mode. A lot of research work have done about the conventional cross-shaped quadrotors but little about oblique cross quadrotors vehicle. The mathematics model of the oblique cross quadrotors vehicle was built up according Newton-Euler formalism and an experimental identification of dynamic parameters is presented. After that, PD was applied to design the control laws. The simulation results demonstrate that the designed control laws can accurately track the given trajectory and have a good performance.

Autonomous mission planning system for unmanned aerial vehicle (UAV) has the ability to perform complex tasks, during the process of task execution. Due to their own and external conditions may change, Effective self-re-planning aircraft can adapt to these changing conditions in the uninterrupted implementation of the mission objectives. Mission planning is a complex problem. By gradual decomposition of a large target for a number of multi-level independent sub-goals, it can reduce the overall complexity, without losing the characteristics of the whole system. At the same time, the next-generation human-machine interface can increase the ability of UAV operator's assistant decision and control accuracy.