This paper presents a novel navigation system for aiding a classic inertial navigation system with a Vehicle Dynamics Model in a quadrotor application. The navigation system is based on the previously presented Unified Model technique for optimal fusion of the two prediction models. The key point of the approach in this paper is that the required modeling and implementation effort is minimized by incorporating a translational dynamics model only. Even though no rotational vehicle dynamics are modeled, it is shown that the filter is able to estimate roll and pitch angles and even IMU biases with bounded errors. Indoor and outdoor flight experiments confirm that all navigation states except heading angle are significantly improved compared to the single systems. For the first time, this demonstrates in real flight experiments that model‐aided navigation allows estimating a full navigation solution for several minutes even without any aiding sensors. Copyright © 2014 Institute of Navigation.

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Micro Aerial Vehicles (MAV) with vertical takeoff and landing capabilities such as quadrotors are often used as sensor platforms. The carried equipment like cameras or LASER range finders has to be aligned to some point of interest. In this article a modified type of a quadrotor will be presented: a quadrotor with tilt able rotors which in contrast to common quadrotors is able to perform independent velocity and attitude movements. This ability makes additional aligning equipment to move the payload redundant. After a system description, the used control algorithm based on Nonlinear Inverse Dynamics (NID) is explained. In this article an extension of this approach is presented. The pseudo control hedging method removes the influence of the actuator dynamics from the control loop. The extension and its integration into the control algorithm are explained and the influence on the quality of control is demonstrated by simulation results.

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