JSBSim Open-Source Flight Dynamics Model for Fixed-Wing Unmanned Aerial Vehicle Applications

Simulation packages provide a valuable framework or environment to study the interaction between aircraft, including Unmanned Aerial Vehicles (UAVs), in the existent air traffic in near mid-air collision (NMAC) scenarios. The proposed simulation package is based on the open-source JSBSim Flight Dynamics Model (FDM) and our developments represent the UAVs with the required precision to model those interactions. This tool has been validated and tested in UAV computer models and is currently being used in 4D encounters and avoidance maneuvers. The final objective of this paper is to provide a simplified model version of the current package, the including the minimum requirements for the design of a UAV in JSBSim, and guide any modeler through the UAV computer design task

Comparison of Medium and Long Wave Infrared Imaging for Ocean Based Sensing

Infrared thermal imagers convert the radiation received by a detector into a false colour visual image which represents the temperature profile of a scene or object. The selection of an infrared sensor for ocean based imaging is complicated, and depends on the intended use and target characteristics. This paper provides a theoretical understanding of the physics associated with the energy collected by the sensor and the resulting infrared images. Further, explanation of the factors affecting the resulting image with respect to the camera properties is provided. Finally, a variety of examples of airborne thermal images are presented, with detailed explanations of the imaged scenes based on theory and sensor characteristics provided in the previous sections

Visual servoing for autonomous landing of a multi-rotor UAS on a moving platform

In this paper, a method to control a small multi-rotor unmanned aerial system (UAS) while landing on a moving platform using image-based visual servoing (IBVS) is described. The landing scheme is based on positioning visual markers on a landing platform in the form of a detectable pattern. When the onboard camera detects the object pattern, the flight control algorithm will send visual-based servo-commands to align the multi-rotor with the targets. The main contribution is that proposed method is less computationally expensive as it uses color-based object detection applied to a geometric pattern instead of feature tracking algorithms. This method has the advantage that it does not demand calculating the distance to the objects (depth). The proposed method was tested in simulation using a quadcopter model in V-REP (Virtual Robotics Experimental Platform) working in parallel with Robot Operating System (ROS). Finally, this method was validated in series of real-time experiments with a quadcopter.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

A Harmonic Spectral Beamformer for the Enhanced Localization of Propeller-driven Aircraft

The following paper presents several array processing techniques which may be used to enhance the localization of acoustic source targets such as UAVs. A review of common methods is first provided, followed by several algorithms developed to reduce computational loads for the application of concern. A beamforming method is proposed which exploits the properties of harmonic narrowband signals such as that generated by propeller-driven aircraft to enhance direction of arrival accuracy. In addition, a regional contraction search algorithm is proposed to minimize computational loads associated with the presented localization technique. A brief comparison of the proposed method to that of standard frequency domain beamformers is also provided using both theoretical analysis and experimental data. For the case of target localization between two moving fixed-wing UAVs, it was found that the proposed Harmonic Spectral Beamforming method increased localization accuracy by 50% over the standard Steered Response Power approach.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Discrete Supervisory Control of Hybrid Systems Based on <I> l </I>-Complete Approximations

The topic of this paper is the synthesis of discrete supervisory control for hybrid systems Σ with discrete external signals. Such systems are in general neither l-complete nor can they be represented by finite state machines. Our solution to the contro

Development of small UAS beyond-visual-line-of-sight (BVLOS) flight operations:system requirements and procedures

Due to safety concerns of integrating small unmanned aircraft systems (UAS) into non-segregated airspace, aviation authorities have required a set of detect and avoid (DAA) systems to be equipped on small UAS for beyond-visual-line-of-sight (BVLOS) flight operations in civil airspace. However, the development of small UAS DAA systems also requires BVLOS flights for testing and validation. To mitigate operational risks for small UAS BVLOS flight operations, this paper proposes to initially test small UAS DAA systems in BVLOS flights in a restricted airspace with additional safety features. Later, this paper further discusses the operating procedures and emergency action plans for small UAS BVLOS flight operations. The testing results show that these safety systems developed can help improve operational safety for small UAS BVLOS flight operations

ASSESSMENT OF ALTERNATIVE MANUAL CONTROL METHODS FOR SMALL UNMANNED AERIAL VEHICLES

This paper is a summary of experiments to assess alternative methods to control a small (The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author