AFIT UAV Swarm Mission Planning and Simulation System

The purpose of this research is to design and implement a comprehensive mission planning system for swarms of autonomous aerial vehicles. The system integrates several problem domains including path planning, vehicle routing, and swarm behavior. The developed system consists of a parallel, multi-objective evolutionary algorithm-based path planner, a genetic algorithm-based vehicle router, and a parallel UAV swarm simulator. Each of the system\u27s three primary components are developed on AFIT\u27s Beowulf parallel computer clusters. Novel aspects of this research include: integrating terrain following technology into a swarm model as a means of detection avoidance, combining practical problems of path planning and routing into a comprehensive mission planning strategy, and the development of a swarm behavior model with path following capabilities

Cruise Missile Integrated Air Defense System Penetration: Modeling the S-400 System

This research determines improved flight-path routes that make maximum utilization of terrain-masking opportunities, and defending radar and missile system equipment performance and launch timing constraints, in order to avoid radar detection and tracking, and to mitigate subsequent missile shoot-down risks. The problem is formulated as one of constrained optimization in three dimensions. Advantageous solutions are identified using the A* Algorithm in conjunction with detailed equipment performance and constraint calculations and high-resolution digital terrain elevation maps. Topographical features in digital terrain are exploited by the algorithm to avoid radar detection and tracking. The model includes provisions for all-aspect/all-frequency radar cross section variations, radar horizon masking, and specific factors relevant to the TLAM BGM-109 cruise missile and the Russian S-400 long-range and Pantsir point-defense IADS systems. Research conclusions indicate that intelligent exploitation of modeled system technical and performance capabilities and limitations yields improved survivability in conjunction with, and supplementing, terrain masking

Airborne laser sensors and integrated systems

The underlying principles and technologies enabling the design and operation of airborne laser sensors are introduced and a detailed review of state-of-the-art avionic systems for civil and military applications is presented. Airborne lasers including Light Detection and Ranging (LIDAR), Laser Range Finders (LRF), and Laser Weapon Systems (LWS) are extensively used today and new promising technologies are being explored. Most laser systems are active devices that operate in a manner very similar to microwave radars but at much higher frequencies (e.g., LIDAR and LRF). Other devices (e.g., laser target designators and beam-riders) are used to precisely direct Laser Guided Weapons (LGW) against ground targets. The integration of both functions is often encountered in modern military avionics navigation-attack systems. The beneficial effects of airborne lasers including the use of smaller components and remarkable angular resolution have resulted in a host of manned and unmanned aircraft applications. On the other hand, laser sensors performance are much more sensitive to the vagaries of the atmosphere and are thus generally restricted to shorter ranges than microwave systems. Hence it is of paramount importance to analyse the performance of laser sensors and systems in various weather and environmental conditions. Additionally, it is important to define airborne laser safety criteria, since several systems currently in service operate in the near infrared with considerable risk for the naked human eye. Therefore, appropriate methods for predicting and evaluating the performance of infrared laser sensors/systems are presented, taking into account laser safety issues. For aircraft experimental activities with laser systems, it is essential to define test requirements taking into account the specific conditions for operational employment of the systems in the intended scenarios and to verify the performance in realistic environments at the test ranges. To support the development of such requirements, useful guidelines are provided for test and evaluation of airborne laser systems including laboratory, ground and flight test activities

Low altitude threat evasive trajectory generation for autonomous aerial vehicles

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2004.Includes bibliographical references (p. 117-119).In recent years, high altitude unmanned aerial vehicles have been used to great success in combat operations, providing both reconnaissance as well as weapon launch platforms for time critical targets. Interest is now growing in extending autonomous vehicle operation to the low altitude regime. Because perfect threat knowledge can never be assumed in a dynamic environment, an algorithm capable of generating evasive trajectories in response to pop-up threats is required. Predetermination of contingency plans is precluded due to the enormity of possible scenarios; therefore, an on-line vehicle trajectory planner is desired in order to maximize vehicle survivability. This thesis presents a genetic algorithm based threat evasive response trajectory planner capable of explicitly leveraging terrain masking in minimizing threat exposure. The ability of genetic algorithms to easily incorporate line-of-sight effects, the inherent ability to trade off solution quality for reduced solution time, and the lack of off-line computation make them well suited for this application. The algorithm presented generates trajectories in three-dimensional space by commanding changes in velocity magnitude and orientation. A crossover process is introduced that links two parent trajectories while preserving their inertial qualities. Throughout the trajectory generation process vehicle maneuverability limits are imposed so that the resultant solutions remain dynamically feasible.(cont.) The genetic algorithm derived provides solutions over a fixed time horizon, and is implemented in a receding horizon fashion, thereby allowing evasion of threat areas of arbitrary size. Simulation results are presented demonstrating the algorithm response for a rotorcraft encountering several different threat scenarios designed to evaluate the effectiveness of the algorithm at minimizing risk to the vehicle.by Ryan L. Pettit.S.M

Autonomous Collision avoidance for Unmanned aerial systems

Unmanned Aerial System (UAS) applications are growing day by day and this will lead Unmanned Aerial Vehicle (UAV) in the close future to share the same airspace of manned aircraft.This implies the need for UAS to define precise safety standards compatible with operations standards for manned aviation. Among these standards the need for a Sense And Avoid (S&A) system to support and, when necessary, sub¬stitute the pilot in the detection and avoidance of hazardous situations (e.g. midair collision, controlled flight into terrain, flight path obstacles, and clouds). This thesis presents the work come out in the development of a S&A system taking into account collision risks scenarios with multiple moving and fixed threats. The conflict prediction is based on a straight projection of the threats state in the future. The approximations introduced by this approach have the advantage of high update frequency (1 Hz) of the estimated conflict geometry. This solution allows the algorithm to capture the trajectory changes of the threat or ownship. The resolution manoeuvre evaluation is based on a optimisation approach considering step command applied to the heading and altitude autopilots. The optimisation problem takes into account the UAV performances and aims to keep a predefined minimum separation distance between UAV and threats during the resolution manouvre. The Human-Machine Interface (HMI) of this algorithm is then embedded in a partial Ground Control Station (GCS) mock-up with some original concepts for the indication of the flight condition parameters and the indication of the resolution manoeuvre constraints. Simulations of the S&A algorithm in different critical scenarios are moreover in-cluded to show the algorithm capabilities. Finally, methodology and results of the tests and interviews with pilots regarding the proposed GCS partial layout are covered

UAVs for the Environmental Sciences

This book gives an overview of the usage of UAVs in environmental sciences covering technical basics, data acquisition with different sensors, data processing schemes and illustrating various examples of application