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Viewing 1 to 30 of 110
2017-03-14
Journal Article
2017-01-9276
Joseph K. Ausserer, Marc D. Polanka, Jacob A. Baranski, Keith D. Grinstead, Paul J. Litke
Abstract The rapid expansion of the market for remotely piloted aircraft (RPA) includes a particular interest in 10-25 kg vehicles for monitoring, surveillance, and reconnaissance. Power-plant options for these aircraft are often 10-100 cm3 internal combustion engines. Both power and fuel conversion efficiency decrease with increasing rapidity in the aforementioned size range. Fuel conversion efficiency decreases from ∼30% for conventional-scale engines (>100 cm3 displacement) to <5% for micro glow-fuel engines (<10 cm3 displacement), while brake mean effective pressure decreases from >10 bar (>100 cm3) to <4 bar (<10 cm3). Based on research documented in the literature, the losses responsible for the increase in the rate of decreasing performance cannot be clearly defined.
2017-01-10
Technical Paper
2017-26-0336
Ganesh Liladhar Yewale, Abhishek Tapkire, D Radhakrishna, Popat Shejwal, Kaushal Singh, Gaurav Panchal
Abstract VRDE has developed Wankel type rotary engine to achieve high power output & fuel efficiency for indigenization programme of UAVs. This engine is meeting all performance parameters needed for intended aerial vehicle. This paper describes the testing methodology followed by development engineers to prove the endurance and reliability of UAV engine for airworthiness certification. This paper gives the brief about testing carried out on the Wankel engine, failures faced during endurance testing and their rectification to enhance the life of the engine to achieve hundred test cycle mark. This paper also briefs about the test set up, endurance test cycles simulating the practical operating conditions.
2016-11-08
Technical Paper
2016-32-0045
Joseph K. Ausserer, Marc D. Polanka, Jacob Baranski, Paul Litke
Abstract Small remotely piloted aircraft (10-25 kg) powered by internal combustion engines typically operate on motor gasoline, which has an anti-knock index (AKI) of >80. To comply with the single-battlefield-fuel initiative in DoD Directive 4140.25, interest has been increasing in converting the 1-10 kW power plants in the aforementioned size class to run on lower AKI fuels such as diesel and JP-8, which have AKIs of ∼20. It has been speculated that the higher losses (short circuiting, incomplete combustion, heat transfer) that cause these engines to have lower efficiencies than their conventional-scale counterparts may also relax the fuel-AKI requirements of the engines. To investigate that idea, the fuel-AKI requirement of a 3W-55i engine was mapped and compared to that of the engine on the manufacturer-recommended 98 (octane number) ON fuel.
2016-11-08
Technical Paper
2016-32-0078
Mark R. Mataczynski, Paul Litke, Benjamin Naguy, Jacob Baranski
Abstract Aircraft engine power is degraded with increasing altitude according to the resultant reduction in air pressure, temperature, and density. One way to mitigate this problem is through turbo-normalization of the air being supplied to the engine. Supercharger and turbocharger components suffer from a well-recognized loss in efficiency as they are scaled down in order to match the reduced mass flow demands of small-scale Internal Combustion Engines. This is due in large part to problems related to machining tolerance limitations, such as the increase in relative operating clearances, and increased blade thickness relative to the flow area. As Internal Combustion Engines decrease in size, they also suffer from efficiency losses owing primarily to thermal loss. This amplifies the importance of maximizing the efficiency of all sub-systems in order to minimize specific fuel consumption and enhance overall aircraft performance.
2016-10-25
Technical Paper
2016-36-0437
Gustavo de Carvalho Bertoli, Geraldo José Adabo, Gefeson Mendes Pacheco
Abstract A method for conceptual design of Solar Powered Unmanned Aircraft System (UAS) is presented. This method is based on traditional design methodology - wing loading estimation for preliminary sizing - modified for Solar Powered UAS case. Based on past works on Solar Powered UAS design, proposes a method that considers payload power consumption and therefore its impact on battery sizing. This battery sizing composes vehicle conceptual sizing equation. This method is useful for an assessment of Solar Powered UAS use in specific missions and serving as a start point for a more detailed design. A user interface was developed to automate the design process based on this method proposed.
2016-09-20
Technical Paper
2016-01-1980
Syama M. Rao, Dineshkumar M
Abstract This paper studies admissible state trajectories for an unmanned aerial vehicle(UAV) by performing dynamic soaring technique in the wind gradient. An optimization problem is formulated by employing direct optimal piece wise control. A 3-DOF point mass model system dynamics of UAV is considered. The bank angle and lift co-efficient are identified as control variables. A UAV of mass 5.44kg is considered for this study. Performance measures considered are maximization of specific energy and maximization of specific energy rate extracted by the vehicle, and minimization of the control effort. The effects of linear and parabolic wind gradient on maximizing the specific energy of an autonomous dynamic soaring UAV is also studied and minimum linear gradient required is found. The loop radius of the loiter pattern is maximized for applications like surveillance and patrolling of a localized area along with energy maximization as objective function.
2016-09-20
Technical Paper
2016-01-2004
M. Parvez Alam, Dinesh Manoharan
In this paper we discuss about the design and development of an “Autonomous Amphibious Unmanned Aerial Vehicle (AAUAV)” that can fly autonomously to the polluted water areas where human accessibility is formidable to test the water quality. The AAUAV system is an integrated multi-copter with tilt rotor capability to facilitate easy landing, navigation and maneuver on water. A 3D CAD model has been designed and analyzed. A specific propulsion system has been devised and lab tested. A proof of concept model has been made and tested in the field with its instruments to ascertain its technical/ operational feasibility. This system can also be tailored to collect and store the water samples from the polluted sites for further comprehensive research at the laboratory. AAUAV system is the novel solution to the polluted environment through a complete integrated system. This will be an effective alternative for the conventional water sampling techniques.
2016-04-05
Technical Paper
2016-01-1467
Neal Carter, Alireza Hashemian, Nathan A. Rose, William T.C. Neale
Abstract Improvements in computer image processing and identification capability have led to programs that can rapidly perform calculations and model the three-dimensional spatial characteristics of objects simply from photographs or video frames. This process, known as structure-from-motion or image based scanning, is a photogrammetric technique that analyzes features of photographs or video frames from multiple angles to create dense surface models or point clouds. Concurrently, unmanned aircraft systems have gained widespread popularity due to their reliability, low-cost, and relative ease of use. These aircraft systems allow for the capture of video or still photographic footage of subjects from unique perspectives. This paper explores the efficacy of using a point cloud created from unmanned aerial vehicle video footage with traditional single-image photogrammetry methods to recreate physical evidence at a crash scene.
2015-09-22
Technical Paper
2015-36-0543
Rodolfo Antonio da Silva Araujo, José Antonio Rodrigues, Marcelo Lopes de Oliveira e Souza
Abstract The increasing development of Unmanned Aerial Vehicle (UAV) technologies has allowed greater use of UAVs as remote sensing platforms to enhance satellite and manned aerial vehicle remote sensing surveillance and environmental management systems. Particularly, the Brazilian National Institute for Space Research - INPE has an Environmental Data Collection System (SCD) since 1993. Recently, the MCTI (Ministry of Science, Technology and Innovation) opened the National Center for Monitoring and Early Warning of Natural Disasters (CEMADEN). Both may need additional resources for their expansions in the near future as offered by UAV technologies. These needs illustrate the potential of UAV technologies as complement to existing or future systems. This paper presents an overview of data transmission used in UAVs for remote sensing surveillance and environmental management systems.
2015-09-22
Technical Paper
2015-36-0364
Everton Spuldaro, Justin Donoghue, Jacob Hough, Bruno Rocha
Abstract A long endurance high efficiency Unmanned Aerial Vehicle (UAV) is being developed by a group of researchers and students in the Mechanical Engineering Technology program at Algonquin College, Ottawa, ON, Canada. The design is based on a tailless, staggered tandem wing configuration, with a carbon fiber frame and electric propulsion. The developed aircraft has a maximum weight of 12.5 kg, well within the 25 kg limit outlined by Transport Canada for permission-free operation. The UAV was designed to fly missions exceeding 24 hours, performing surveillance and oil pipeline monitoring and inspection, either autonomously or under radio control from a ground station, with medium to high payload capacity. This paper describes the process of designing, manufacturing and testing the developed configuration. The operational requirements are delineated as conceptualized by the development team.
2015-09-15
Technical Paper
2015-01-2424
Alberto Boretti, Shuheng Jiang
Abstract Unmanned Aerial Vehicles (UAV) require simple and reliable engines of high power to weight ratio. Wankel and two stroke engines offer many advantages over four stroke engines. A two stroke engines featuring crank case scavenging, precise oiling, direct injection and jet ignition is analyzed here by using CAD, CFD and CAE tools. Results of simulations of engine performances are shown in details. The CFD analysis is used to study fuel injection, mixing and combustion. The CAE model then returns the engine performances over the full range of loads and speeds with the combustion parameters given as an input. The use of asymmetric rather than symmetric port timing and supercharging scavenging is finally suggested as the best avenue to further improve power density and fuel conversion efficiency.
2015-09-15
Technical Paper
2015-01-2455
Roshen Jay Jaswantlal, Piergiovanni Marzocca, Rafael Palacios
Abstract The implementation of Synthetic Jet Actuators (SJAs) on Unmanned Aerial Vehicles (UAVs) provides a safe test-bed for analysis of improved performance, in the hope of certification of this technology on commercial aircraft in the future. The use of high resolution numerical methods (i.e. CFD) to capture the details of the effects of SJAs on flows and on the hosting lifting surface are computationally expensive and time-consuming, which renders them ineffective for use in real-time flow control implementations. Suitable alternatives include the use of Reduced Order Models (ROMs) to capture the lower resolution overall effects of the jets on the flow and the hosting structure. This research paper analyses the effects of SJAs on aircraft wings using a ROM for the purpose of determining the unsteady aerodynamic forces modified by the presence of the SJAs. The model developed is a 3D unsteady panel code where the jets are represented by source panels.
2015-09-15
Technical Paper
2015-01-2454
Patrick H. Browning, Wade Huebsch
Abstract The design and testing of small unmanned aerial vehicle (sUAV) prototypes can provide numerous difficulties when compared to the same process applied to larger aircraft. In most cases, it is desirable to have a better understanding of the low Reynolds number aerodynamics and stability characteristics prior to completion of the final sUAV design. This paper describes the design, construction, and operational performance of a pneumatic launch apparatus that has been used at West Virginia University (WVU) for the development and early flight testing of transforming sUAV platforms. Although other launch platforms exist that can provide the safe launch of such prototypes, the particular launch apparatus constructed at WVU exhibits unmatched launch efficiency, and is far less expensive to operate per shot than any other launch system available.
2015-09-15
Technical Paper
2015-01-2461
Enrico Troiani, Maria Pia Falaschetti, Sara Taddia, Alessandro Ceruti
Abstract The high number of hull losses is a main concern in the UAV field, mostly due to the high cost of on-board equipment. A crashworthiness design can be helpful to control the extent and position of crash impact damage, minimizing equipment losses. However, the wide use of composite materials has recently put the accent on the lack of data about the behavior of these structures under operative loads, such as the crash conditions. This paper presents the outcome of a set of tests carried out to achieve a controlled crush of UAV structures, and to maximize the Specific Energy Absorption. In this work, a small-scale experimental test able to characterize the energy absorption of a Carbon-fiber-reinforced polymer under compression was developed introducing self-supporting sinusoidal shape specimens, which avoid the need for complex anti-buckling devices.
2015-09-15
Technical Paper
2015-01-2460
Melissa Arras, Giuliano Coppotelli, Piergiovanni Marzocca, Antonio Simone Mezzapesa
Abstract In this paper the finite element model of an Unmanned Aerial Vehicle is updated by using experimental data coming from a standard ground vibration test in order to improve the numerical-experimental correlation. A sensitivity-based updating methodology that iteratively minimizes a residual vector, defined on the modal parameters (e.g. natural frequencies and mode shapes), is considered to identify the unknown values of the updating parameters. The structure under investigation is the Clarkson University Golden Eagle UAV. An initial numerical model of the structure is obtained by assembling the individual components previously updated which included wings, fuselage, horizontal tail, vertical tails and tail booms. As a result the identification procedure shifts its focus on the joints between UAV elements which could not be modeled accurately in earlier investigations.
2015-09-15
Technical Paper
2015-01-2457
Jae Chung, Yushing Cheung
Abstract In this paper, we investigate the formation control of multiple unmanned aerial vehicles (UAVs) in an obstacle-laden environment for target tracking. The main contribution of this paper is to develop a potential field based leader-follower formation control method for target tracking and obstacle/collision avoidance. In the potential field, a quantity of virtual positive charge carried by each of UAVs varies depending upon their roles as a leader or follower when obstacles and targets are regarded as ions with larger positive and negative charges, respectively. Therefore, the formation formed by the UAVs connected with their inter-bonds could be adapted while the UAVs get around the obstacles and are attracted to the targets. The potential field based leader-follower formation control method is developed to reshape a UAV team configuration to track a target while the UAV team avoids the obstacles.
2015-09-15
Technical Paper
2015-01-2471
Alessandro Ceruti, Simone Curatolo, Alessandro Bevilacqua, Piergiovanni Marzocca
Abstract The maturity reached in the development of Unmanned Air Vehicles (UAVs) systems is making them more and more attractive for a vast number of civil missions. Clearly, the introduction of UAVs in the civil airspace requiring practical and effective regulation is one of the most critical issues being currently discussed. As several civil air authorities report in their regulations “Sense and Avoid” or “Detect and Avoid” capabilities are critical to the successful integration of UAV into the civil airspace. One possible approach to achieve this capability, specifically for operations beyond the Line-of-Sight, would be to equip air vehicles with a vision-based system using cameras to monitor the surrounding air space and to classify other air vehicles flying in close proximity. This paper presents an image-based application for the supervised classification of air vehicles.
2015-09-15
Technical Paper
2015-01-2468
Rebecca Margetts, Chris Bingham, Tim Smith
Abstract Nonlinear Dynamic Inversion (NDI) has been previously reported for application to unmanned aircraft systems, due to the inherent attributes of allowing global co-ordinates to be used directly as control inputs. Here, the paper describes a model implementation of an ACHEON propulsion/thrust vectoring system that can be applied to a range of aircraft, with specific emphasis to thrust vectoring of a UAV. Results from the studies show the overall performance is shown to provide improved stability and dynamic characteristics when augmented with additional classical (PI based) control schemes.
2015-09-15
Technical Paper
2015-01-2467
Luca Gallo, Bernard Tashie-Lewis, Panos Laskaridis, Paul Miller, Mark Husband
Abstract The present work focuses on developing an integrated airframe, distributed propulsion, and power management methodology for liquid-hydrogen-fuelled HALE UAVs. Differently from previous studies, the aim is to assess how the synergies between the aforementioned sub-systems affect the integrated system power requirement, production, and distribution. A design space exploration study was carried out to assess the influence of distributing motor-driven fans on three different airframes, namely a tube-and-wing, a triple-fuselage, and a blended-wing-body. For the considered range of take-off masses from 5,000 to 15,000 kg, the 200 kW payload power requirement under examination was found to re-shape the endurance trends. In fact, the drop in specific fuel consumption due to the engine design point change alters the trends from nearly flat to a 25% maximum endurance increase when moving towards heavier take-off masses.
2015-09-15
Technical Paper
2015-01-2465
Michele Trancossi, Chris Bingham, Alfredo Capuani, Shyam Das, Antonio Dumas, Francesco Grimaccia, Mauro Madonia, Jose Pascoa, Tim Smith, Paul Stewart, Maharshi Subhash, Anna Sunol, Dean Vucinic
Abstract This paper presents a novel UAS (Unmanned Aerial System) designed for excellent low speed operations and VTOL performance. This aerial vehicle concept has been designed for maximizing the advantages by of the ACHEON (Aerial Coanda High Efficiency Orienting-jet Nozzle) propulsion system, which has been studied in a European commission under 7th framework programme. This UAS concept has been named MURALS (acronym of Multifunctional Unmanned Reconnaissance Aircraft for Low-speed and STOL operation). It has been studied as a joint activity of the members of the project as an evolution of a former concept, which has been developed during 80s and 90s by Aeritalia and Capuani. It has been adapted to host an ACHEON based propulsion system. In a first embodiment, the aircraft according to the invention has a not conventional shape with a single fuselage and its primary objective is to minimize the variation of the pitching moment allowing low speed operations.
2015-09-15
Technical Paper
2015-01-2472
Tom Owen
Abstract SUAV is a 4 year investigation with the aim of designing, manufacturing and integrating a 3kg Solid Oxide Fuel Cell (SOFC) into an existing 11kg fixed wing UAV which is already in commercial service. The project comprises of a collaboration of ten partners, each having a commercial or scientific interest in the design. Individual partners provide specific specialist knowledge at system component level. This paper will present an overview of the problem space and show the methods used to generate the system level requirements. A top level overview of the resultant system design is also given.
2015-09-15
Technical Paper
2015-01-2459
Francesco Cappello, Subramanian Ramasamy, Roberto Sabatini
Abstract Multi-Sensor Data Fusion (MSDF) techniques involving satellite and inertial-based sensors are widely adopted to improve the navigation solution of a number of mission- and safety-critical tasks. Such integrated Navigation and Guidance Systems (NGS) currently do not meet the required level of performance in all flight phases of small Remotely Piloted Aircraft Systems (RPAS). In this paper an innovative Square Root-Unscented Kalman Filter (SR-UKF) based NGS is presented and compared with a conventional UKF governed design. The presented system architectures adopt state-of-the-art information fusion approach based on a number of low-cost sensors including; Global Navigation Satellite Systems (GNSS), Micro-Electro-Mechanical System (MEMS) based Inertial Measurement Unit (IMU) and Vision Based Navigation (VBN) sensors.
2015-09-15
Technical Paper
2015-01-2477
Alessandro Gardi, Roberto Sabatini
Abstract This paper presents the conceptual design of a new low-cost measurement system for the determination of pollutant concentrations associated with aircraft operations. The proposed system employs Light Detection and Ranging (LIDAR) and passive electro-optics equipment installed in two non-collocated components. The source component consists of a tuneable small-size and low-cost/weight LIDAR emitter, which can be installed either on airborne or ground-based autonomous vehicles, or in fixed surface installations. The sensor component includes a target surface calibrated for reflectance and passive electro-optics equipment calibrated for radiance, both installed on an adjustable support. The proposed bistatic system determines the column-averaged molecular and aerosol pollutant concentrations along the LIDAR beam by measuring the cumulative absorption and scattering phenomena along the optical slant range.
2015-09-15
Technical Paper
2015-01-2463
Giacomo Frulla, Enrico Cestino, Piero Gili, Michele Visone, Domenico Scozzola
Abstract The problem of wing shape modification under loads in order to enhance the aircraft performance and control is continuously improving by researchers. This requirement is in contrast to the airworthiness regulations that constraint stiffness and stress of the structure in order to maintain structural integrity under operative flight conditions. The lifting surface modification is more stringent in those cases, such as UAV configurations, where the installed power is limited but the variety of operative scenario is wider than in conventional aircraft. A possible solution for adaptive wing configuration can be found in the VENTURAS Project idea. The VENTURAS Project is a funded project with the aim of improve the wind turbine efficiency by means of introducing a twisting capability for the blade sections according to the best situation in any wind condition. The blade structure is composed by two parts: 1) internal supporting element, 2) external deformable envelope.
2015-09-15
Technical Paper
2015-01-2473
Alessandro Ceruti, Alfredo Liverani, Piergiovanni Marzocca
Abstract Traditional User/Maintenance Manuals provide useful information when dealing with simple machines. However, when dealing with complex systems of systems and highly miniaturized technologies, like UAVs, or with machines with millions of parts, a commercial aircraft is a case in point, new technologies taking advantage of Augmented Reality can rapidly and effectively support the maintenance operations. This paper presents a User/Maintenance Manual based on Augmented Reality to help the operator in the detection of parts and in the sequence to be followed to assemble/disassemble systems and subsystems. The proposed system includes a handheld device and/or an head mounted display or special goggles, to be used by on-site operators, with software management providing data fusion and overlaying traditional 2D user/maintenance manual information with an augmented reality software and appropriate interface.
2015-09-15
Technical Paper
2015-01-2528
Srikanth Gururajan
Abstract In recent years, there has been an increase in the use of Unmanned Aerial Systems (UAS) in the civilian sector for various purposes. As these platforms are constrained in terms of payload and capacity, they are typically equipped with a minimal sensor suite and the use of redundant sensors is uncommon. This research effort describes the design and simulation of a Neural Network (NN) based fault tolerant flight control approach for sensor and actuator failures, implemented on a parallel and distributed computational architecture. The inter process communication is implemented using BSD sockets and Message Passing Interface (MPI). For the purpose of the sensor failure detection, identification and accommodation (SFDIA) task, it is assumed that the pitch, roll and yaw rate gyros onboard the aircraft are without physical redundancy.
2015-09-15
Technical Paper
2015-01-2456
Roberto Sabatini, Terry Moore, Chris Hill, Subramanian Ramasamy
Abstract Global Navigation Satellite Systems (GNSS) can support the development of low-cost and high performance navigation and guidance architectures for Unmanned Aircraft Systems (UAS) and, in conjunction with suitable data link technologies, the provision of Automated Dependent Surveillance (ADS) functionalities for cooperative Sense-and-Avoid (SAA). In non-cooperative SAA, the adoption of GNSS can also provide the key positioning and, in some cases, attitude data (using multiple antennas) required for automated collision avoidance. A key limitation of GNSS for both cooperative (ADS) and non-cooperative applications is represented by the achievable levels of integrity. Therefore, an Avionics Based Integrity Augmentation (ABIA) solution is proposed to support the development of an Integrity-Augmented SAA (IAS) architecture suitable for both cooperative and non-cooperative scenarios.
2015-09-15
Technical Paper
2015-01-2474
Christopher W. Lum, Alexander Summers, Brian Carpenter, Angel Rodriguez, Matthew Dunbabin
Abstract In many parts of the world, uncontrolled fires in sparsely populated areas are a major concern as they can quickly grow into large and destructive conflagrations in short time spans. Detecting these fires has traditionally been a job for trained humans on the ground, or in the air. In many cases, these manned solutions are simply not able to survey the amount of area necessary to maintain sufficient vigilance and coverage. This paper investigates the use of unmanned aerial systems (UAS) for automated wildfire detection. The proposed system uses low-cost, consumer-grade electronics and sensors combined with various airframes to create a system suitable for automatic detection of wildfires. The system employs automatic image processing techniques to analyze captured images and autonomously detect fire-related features such as fire lines, burnt regions, and flammable material.
2015-09-15
Technical Paper
2015-01-2475
Francesco Cappello, Roberto Sabatini, Subramanian Ramasamy
Abstract Accurate and robust tracking of objects is of growing interest amongst the computer vision scientific community. The ability of a multi-sensor system to detect and track objects, and accurately predict their future trajectory is critical in the context of mission- and safety-critical applications. Remotely Piloted Aircraft System (RPAS) are currently not equipped to routinely access all classes of airspace since certified Detect-and-Avoid (DAA) systems are yet to be developed. Such capabilities can be achieved by incorporating both cooperative and non-cooperative DAA functions, as well as providing enhanced communications, navigation and surveillance (CNS) services. DAA is highly dependent on the performance of CNS systems for Detection, Tacking and avoiding (DTA) tasks and maneuvers.
2015-09-15
Technical Paper
2015-01-2470
Subramanian Ramasamy, Roberto Sabatini, Alessandro Gardi
Abstract A unified approach to cooperative and non-cooperative Detect-and-Avoid (DAA) is a key enabler for Remotely Piloted Aircraft System (RPAS) to safely and routinely access all classes of airspace. In this paper state-of-the-art cooperative and non-cooperative DAA sensor/system technologies for manned aircraft and RPAS are reviewed and the associated multi-sensor data fusion techniques are discussed. A DAA system architecture is presented based on Boolean Decision Logics (BDL) for selecting non-cooperative and cooperative sensors/systems including both passive and active Forward Looking Sensors (FLS), Traffic Collision Avoidance System (TCAS) and Automatic Dependent Surveillance - Broadcast (ADS-B). After elaborating the DAA system processes, the key mathematical models associated with both non-cooperative and cooperative DAA functions are presented.
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