Browse Topic: Unmanned aerial vehicles
The development of a coupled computational structural dynamics (CSD) and electrodynamic suspension (EDS) system was critical in modeling and predicting the aeromechanics of MagLev Aero's (MLA) propulsion system, ensuring safe testing and proving viability of levitated rotors for vertical lift systems. This advancement validates the feasibility of this enabling technology in applications of uncrewed aerial systems (UAS) with high hover lift efficiencies. This paper explores the implementation of an electromagnetic motor hub on a large-root-cutout, slowed rotor system with a specific focus on the impacts on aeromechanics: loads, performance, vibrations, and aeroelastic stability. The performance benefits of a large-root-cutout system, with an external or internal rotor, are well known; however, the mechanisms to implement such a design have been impractical. The development of an EDS motor bearing enables previously unattainable configurations like large-root-cutout and tip-driven ducted
This study characterizes the dynamics of a novel lag-pitch-coupled underactuated rotor design that can be incorporated into rotary-wing unmanned aerial vehicles (UAVs) to provide pitch and roll control with effectiveness comparable to that of a conventional swashplate albeit with significantly lower mechanical complexity and weight. The concept integrates a single lag hinge tilted at a 45-degree angle located at the center of the rotor hub with independent flap hinges for each of the two blades. This idea relies on the ability to cyclically vary the angular velocity of the rotor in a 1/rev fashion via motor torque modulation, which induces a cyclic lag resulting in a cyclic pitch variation due to the tilted lag hinge (lag-pitch coupling) and causes the tip path plane (TPP) to tilt in a desired direction for pitch and roll control. To understand this concept, simulations using the Rotorcraft Comprehensive Analysis System (RCAS) were performed to capture the 1/rev response in lag, pitch
This paper discusses the development of a quantitatively-accurate non-linear hybrid flight dynamics model of a hover-capable Air-Launched Tailsitter Unmanned Aerial System (ALUAS) in order to 1) understand its dynamics during complicated maneuvers, and 2) provide a high-fidelity framework to develop novel control laws. Wind tunnel tests were conducted on a 1:1 scale model of the full aircraft to measure the airloads, which were used in the simulation as a lookup table. Flight tests of the ALUAS were performed in hover, transition, and cruise to collect a large amount of unique state measurements by providing large excitations to induce highly transient motion. The flight dynamics predictions using Rotorcraft Comprehensive Analysis System (RCAS) software were then compared with experimental flight test data. To correct any discrepancies in the RCAS physics-based predictions, a correction was learned from the experimental measurements, making use of the large amount of collected flight
To document noise characteristics and provide validation data for acoustic modeling of rotor systems appropriate for eVTOL/UAM aircraft, the authors performed an outdoor static test of a subscale 5-blade proprotor. The testing was carried out as part of a program to demonstrate feasibility and overall performance of a quiet proprotor system in support of the eVTOL industry. The authors designed a low-tip speed proprotor to approximate performance required by a 4-5 passenger UAM vehicle. A driving design feature was low-tip speed operation (Mtip ˜0.27) at system disk loadings of 7 to 8 psf (˜3.7 N/m2). The test article was designed as a ground adjustable pitch 5-blade proprotor, with aerodynamic and acoustic data collected in outdoor static hover testing. The test article diameter of 3 feet (0.91 m) represented a scale factor of approximately 30% to 40% compared to vehicles currently in operation or development. The aerodynamic performance in hover was consistent with other rotor
The Rotor Blown Wing (RBW) is a tailsitter Vertical Takeoff and Landing (VTOL) Unmanned Aerial System (UAS) configuration that leverages cutting-edge autonomous flight controls through Sikorsky's MATRIX™ technology to create a highly capable, efficient, and scalable technology platform. By combining the benefits of fixed- and rotary-wing aircraft, the RBW configuration eliminates the need for traditional UAS launch and recovery infrastructure. This paper describes the RBW-5 prototype, a 100-pound, dual 5-foot diameter proprotor demonstrator, and discusses the comprehensive evaluation of its design and operability through a combination of flight tests, wind tunnel experiments, and computational fluid dynamics (CFD) simulations. The results demonstrate the maturity of the UAS and highlights key accomplishments of the RBW-5 program, including successful autonomous takeoff and landing and transitions between hover and forward flight, the extraction of critical "blown-physics" underlying
With recent advancements in the field of Advanced Air Mobility (AAM), including Electric Vertical Takeoff and Landing (eVTOL), Remotely Piloted Aircraft Systems (RPAS), and Unmanned Aerial System (UAS), it is beneficial to understand the impact of complex flow features on operations in urban and shipboard environments. Testing methods for studying these impacts, including simulated environments such as wind-tunnel flows and engineered equivalence tests, will need to be adapted to prepare for when the vehicles of interest are too large for the available testing facilities, and to permit low-cost alternatives for industry and government. This work demonstrates a development process that can be used to ensure the complex-flow-environment phenomena can be studied. First, this work illustrates the development of downdraft and turbulence flow types in a wind tunnel setting, and assesses the response of an M600 RPAS to these flows. Then, the same parameters are compared for a Mission Task
A simulation framework is essential for the development of a hybrid-electric tilt-wing aircraft such as Dufour Aerospace's Aero2 drone. The tilt-wing design with its complex interaction effects between the propellers and the aerodynamic surfaces presents unique modeling challenges, especially during early stages of development when only limited data is available. Furthermore, a delicate balance between accuracy and performance must be found while keeping complexity low to allow for rapid development. This paper introduces a modular design approach for a simulation framework, details the aero-propulsive models and shows ways to validate them using flight data and a system identification approach. By implementing models that capture all relevant effects, the framework helps building a deeper understanding for the dynamics of individual systems, serves as a basis for the design of the flight controller and offers capabilities for pilot training and hardware testing.
Huma, a reconfigurable lift compounded single main rotor (SMR) helicopter, developed by the UMD Graduate Design Team, is capable of exceptional flight time, able to loiter 185-km away from its takeoff point for over 13 hours before needing to return.
Active vibration damping by rotor torque modulation has been demonstrated for vibratory modes in the rotor disk plane. In this study, we introduce a simple, first-principles model, which includes kinematic coupling between lag movement and blade pitch, in order to extend damping authority to strut vibratory modes normal to the rotor disk plane. Using a medium-sized (12kg) quadcopter drone model, we demonstrate the capability to excite strut vibrations normal to the rotor disk plane, indicating control authority for vibration damping. For this vehicle model, a steady state strut deflection of over 12% is obtained using a 15% voltage perturbation, with under 2% rotor speed change. Redesign of the vehicle to have lower and/or co-located lag and structural frequencies increases the control authority of rotor torque actuation with pitch-lag coupling.
This paper presents a distributed algorithm to track a desired target while fostering the emergence of a swarm formation and providing obstacle avoidance capability to deal with unknown scenarios. The proposed approach is based on the merge between a Flight Management System for global path planning and the definition of virtual forces through a custom Artificial Potential Field to prevent drones collisions between each other, with external objects and to provide cohesion of the swarm configuration. Each drone independently computes its global route and adjusts its path based on an optimal control action to minimize a potential energy function induced by its neighbors and obstacles. This approach results in a high cost-effective strategy to enhance UAVs autonomy level by managing a large group of drones, guaranteeing a low cost per unit thanks to the low computational effort and low-budget sensor suit while providing all the capabilities to accomplish the desired mission.
This paper explores the effect of addition of a horizontal tail on the longitudinal stability and performance of a Biplane Tailsitter Unmanned Aerial Vehicle (UAV). Biplane tailsitters a type of hybrid UAVs, often exhibits poor longitudinal stability during forward flight, necessitating continuous active control through application of differential motor thrust to maintain attitude. To address this challenge, this work proposes the integration of a horizontal tail on a quadrotor biplane tailsitter UAV, aiming to improve pitch stability and control authority during critical flight phases. Experimental flight data was utilized to determine the appropriate sizing of the elevator. A detailed flight dynamics model validated the effectiveness of the elevator control. The design was validated through outdoor flight testing, comparing the performance of tail-less and tail-attached configurations. The results demonstrate that the modified design results in a reduction control power requirement
Commercial viability for new unmanned aircraft in markets such as the European Union (EU) requires moving closer to population centers, flying Beyond Visual Line of Sight (BVLOS), and operating in busier airspaces – transitioning to medium-risk SORA SAIL III and SAIL IV operations. This requires a paradigm shift from primarily startup-style, minimalist system architecture modeling, documentation, and safety analyses–if any–towards the rigor expected in classical certification processes (e.g. ARP4754 and ARP4761). Model-based systems engineering (MBSE) and safety analysis (MBSA) methodologies have the potential to greatly aid in this transition: central models can more efficiently capture technical complexity, leverage component redundancy, and allow for easier sharing and re-use of system elements among specialized engineering tools. Larger all-encompassing MBSE/MBSA tools are expected to be particularly useful for their flexibility–providing for current and future needs, as more
Helicopters' Vertical Take-Off and Landing (VTOL) capabilities are essential for maritime operations, especially for small-deck naval vessels. Unmanned Aerial Vehicles (UAVs) offer a cheaper, expendable, and efficient alternative for certain tasks, such as reducing pilot risk and lowering fuel consumption. While the procedures to approach and land on (moving) ships are standardized and bound to established operational limits in the case of crewed helicopters, UAVs lack such guidelines. This study investigates optimal rotary-wing UAV approach trajectories to a moving ship, for varying wind conditions and relative initial positions, and for different objectives. The goal is to provide preliminary guidelines for maritime UAV recovery operations, and a preliminary estimation of performance-based operational limits. The optimal trajectories are obtained using a global path-performance optimization framework based on Optimal Control Theory. The trajectories are compared to each other and to
This paper presents a multi-aircraft Markov decision process congestion game to resolve multi-aircraft near midair collisions (NMACs) for small unmanned aerial vehicles (sUAVs). Two key features of this framework are: 1) it leverages the concept of strategic equilibria from game theory to define optimality in multi-aircraft near midair encounters and 2) it extends the existing NMAC metrics to stochastic formulations via the occupancy measure of a Markov decision process. This game-theoretic approach decomposes the classically centralized air traffic control objective to multiple objectives that correspond to each aircraft within the NMAC, and as result, provides an aircraft-centric notion of optimality and safety that is well-suited for distributed conflict resolutions in multi-aircraft NMACs. In addition to modeling multi-aircraft as a game, stochastic metrics that extend the deterministic notions of NMACs are explored. The safety and optimality of the Nash equilibrium multi-aircraft
This paper presents insights into a comparative approach to down-select on the most suitable pilot control schemes for eVTOL and powered-lift aircraft. The investigation examines three main areas: (1) experimental flight test performance, (2) flight control analysis, and (3) Human-Machine Interface (HMI) factors. Experiments were conducted to evaluate how various inceptor control schemes were perceived by people of various experience levels, ranging from manned aviation pilots with experience in flying F-16 jets, AH-64D helicopters and high-performance turboprop trainers, to unmanned aviation pilots of various backgrounds, such as with remote control (RC) rotorcraft and RC fixed-wing aircraft, and finally to participants with zero experience with either of these. In this experimental surveying study, all participants were briefed on a standardized mission profile and tasked to fly a VTOL drone and a computer based flight simulator using various flight control schemes. Videos were
Precision flight in windy conditions is a common challenge for multirotor UAS. It is especially challenging for in contact tasks that require high-precision positioning and good disturbance rejection capabilities. Such tasks include landing on high-voltage powerlines for in-contact inspections. This paper presents the implementation of small lateral thrusters to improve the lateral position hold ability of a large power line inspection UAS in windy conditions. Arranged in antagonistic pairs on each side, the lateral thrusters handle the high-frequency but smaller-amplitude wind turbulence components with a frequency split control. Using an identified model of the UAS flight dynamics alongside flight data in high-wind conditions, a control architecture with a frequency split in the lateral axis was optimized to increase the disturbance rejection. Experimental tests showed a 67% reduction in lateral position error with the proposed approach in high-wind conditions.
In this work, a vision-based solution is developed to address the challenge of landing on a ship deck with precision and accuracy. For an autonomous landing, it is important to have a fast and accurate pose estimation system along with a reliable control strategy. This research uses fractal ArUCo markers instead of multiple separate markers to allow smooth pose estimation at different heights. Pose estimates are further improved using an Extended Kalman Filter, and a tracking algorithm then uses these estimates to guide the landing. A four degree-of-freedom (roll, pitch, heave and sway) simulator platform was built and used to validate the algorithm. The accuracy of the vision system is compared against that of a motion capture system. Real-world experiments were performed on different quadrotors to demonstrate tracking and landing on the platform with sway, roll, and pitch motions. The results show that the system is efficient and reliable in achieving safe and successful landings
This study introduces a structured methodology for identifying Control-Equivalent Turbulence Input (CETI) models using rotorcraft flight dynamics simulations. A new Moving Spatial Turbulence Field (MSTF) model was developed to generate input datasets, enabling CETI model identification for four distinct aircraft configurations: a generic utility helicopter resembling the H-60, and three small-scale multi-rotor UAS types—a quadcopter, hexacopter, and octocopter. The CETI models were validated in hover using frequency-domain analysis, with flight-derived CETI models serving as the benchmark. To further assess model performance in forward flight, CETI models for the H-60 were identified at airspeeds ranging from 0 to 140 knots in 40- knot increments. Results indicated that the MSTF-based CETI models for the H-60 effectively captured key spectral features of the flight-test data, though some deviations were observed, potentially due to variability in atmospheric conditions. In contrast
Advanced Air Mobility (AAM) is an innovative concept that aims to revolutionize air transportation through electric and unmanned aircraft, enabling applications such as urban air taxis and medical transport. However, one of the key challenges to its widespread adoption is ensuring safety, particularly in collision avoidance. This study focuses on the development of a perception and guidance system for avoiding collisions with non-cooperative targets, which do not share their position or trajectory. To achieve this, a Frequency-Modulated Continuous Wave (FMCW) radar and an InfraRed(IR) camera are used. Compared to traditional pulsed or panel radars, FMCW radars offer higher resolution, better detection of small and slow-moving objects, and improved performance in cluttered environments. The IR camera enhances situational awareness by providing visual confirmation and additional tracking capability, making this sensor fusion approach particularly suitable for AAM applications. Our
Unmanned Aerial Systems (UAS) are essential in disaster relief. VTOL UAS can take off and land in confined areas without infrastructure, efficiently accessing disaster zones for life-saving missions. The AeroLay, designed for disaster relief, delivers up to 54 kg and can loiter for 17.2 hours to relay cell signals. It features quick battery swaps and an accessible fuel tank for rapid redeployment.
Applications of Unmanned Aerial Vehicles (UAVs) are on the rise. Particularly within the healthcare sector the potential is huge as its cited as the most accepted application. This paper introduces an agent-based simulation to evaluate the network performance of UAV-based logistics networks in healthcare. The simulation is applied to a hypothetical real-world network. During a simulated day, the UAV fleet performs 212 flights, including 97 delivery flights, amounting to 4264 minutes enroute and covering a distance of 5941 kilometers. The analysis reveals average non-idle and mission utilization of 66% and 33%, respectively. The study also calculates annual network costs of EUR 2.23Mn, with a majority of it being direct costs (54.5%). Further sensitivity analysis identifies the biggest influences of battery capacity, C-Rate, and operator-to-UAV ratio on network performance and costs, highlighting these factors as critical for future optimization. Additionally, the benefit of
A system identification study was conducted on a quadrotor unmanned aerial system (UAS) that was free-flying inside the test section of the Naval Surface Warfare Center Carderock Division's Subsonic Wind Tunnel. Motion capture cameras installed in the wind tunnel provided position feedback information to the aircraft in real time, enabling autonomous flights. Longitudinal, lateral, heave, and yaw axis frequency sweeps were conducted at airspeeds up to 20 knots, in 5 knot increments. The extracted flight dynamics model showed excellent agreement in both the time and frequency domains across all airspeeds. Variation in the aircraft's stability derivatives, power usage, and trim information with airspeed was determined. This paper documents the test procedures, challenges with flying aircraft inside the wind tunnel, the controller model, and the system identification results. This free-flight wind tunnel testing methodology has wide applicability to assist with UAS flight control
Multirotor electric Vertical Take-Off and Landing (eVTOL) vehicles and many small unmanned aircraft systems (sUAS) utilize distributed electric propulsion. One concept for reducing the noise of these vehicles involves synchronizing the phase relationships between multiple rotors on the aircraft to control the radiated noise in one or more directions. This paper describes the development of a practical electronic phase synchronization method that can be implemented on multirotor aircraft, experimentally evaluates its effectiveness in controlling the noise of a small hexacopter mounted in an anechoic chamber, and investigates how the configuration of the vehicle influences the ability to control noise. Harmonic noise reductions on the order of 10 dB are demonstrated over a 20◦ azimuthal arc, with limited increases in noise in other directions. Noise amplification by 6 dB is also demonstrated over the same region. Moreover, global noise reductions on the order of 6 dB across nearly all
This paper analyses the possibility of using photovoltaics as additional energy provider for small to medium-sized eVTOL UAVs. A simplified model for eVTOL UAVs, which covers all relevant areas of aircraft design, including aerodynamics, structural mechanics, propulsion and systems modelling, is presented. Sensitivity studies covering various design parameters, such as airfoil, wing geometry and propulsion system selection are performed to show their influence on the configurations' performance. The first result of this paper is, that a photovoltaic powered configuration can outperform a battery electric and it can be worth the effort to implement the solar cells. To achieve this, the aircraft needs to be as aerodynamic efficient as possible. Also higher efficiency solar cells increase the possible performance. Additionally there is a big influence of the time of year and the latitude onto the performance. Secondly a multi mission study is performed. This uses a more detailed model, as
Unmanned Aerial Vehicles (UAVs), particularly Vertical Take-Off and Landing (VTOL) aircraft such as quad-rotors and helicopters, have gained attention for diverse applications in military and civilian domains. However, to increase applications, reducing their power consumption and their restricted payload capacity. This paper describes a method to enhance the thrust capabilities of typical shrouded rotors through a novel rotor design. Beginning with an airfoil with a high lift-to-drag ratio. Blade element momentum theory (BEMT) is used to optimize the rotor's chord and twist distributions systematically along with precise induced velocity prediction in shrouded rotors. Furthermore, a validation process requires rotor manufacturing and experimentation. BEMT harmonizes momentum and blade element theories, offering a comprehensive framework for rotor behavior modeling, especially in hovering conditions. First, second, and third degrees functions are used to express both the chord and
Multirotor UAS spanning Groups 3 and 4 have received increased attention as candidates for tactical resupply missions due to their VTOL capability and payload capacity. The objective of this work is to better understand how the parameters of multicopter UAS flight dynamics models scale with size in support of expanding the Army's unmanned aerial reconnaissance capability. A family of coaxial multirotor UAS spanning Groups 2 and 3 have been flight tested to gather data for flight dynamics modeling and validation. These UAS consist of the TRV-80, TRV-150, and the subscale Eagle platform. A series of test points including static stability, trim shot, frequency sweeps, doublets, and maximum climb rate maneuvers were collected. Wind data was simultaneously collected using a 3-axis ultrasonic anemometer to characterize wind conditions and characteristics during testing. Flight data were collected in varying payload configurations ranging from 0-120 pounds and at flight conditions ranging
Winged Quadcopters are an increasingly popular UAS configuration due to their mechanical simplicity and high degree of aerodynamic efficiency, but this efficiency is highly sensitive to the chosen blade pitch and rotor orientation. In this study, a rotor-wing system representative of a winged quadcopter is simulated and a parametric sweep of blade pitch, rotor tilt, cruise speed, and weight is conducted. At the baseline 30 kts cruise speed and 3 lb vehicle weight, the optimal configuration (blade pitch: 10° – 20°, rotor tilt: 30° – 40°) is 4.4 times more efficient than the baseline Quadrotor Biplane Tailsitter (blade pitch: 0°, rotor tilt: 0°). Even if flight speed and weight is increased (up to 50 kts and 9 lb), combinations of blade pitch and rotor tilt can offer improved efficiency; and at the optimal condition, 12.5° blade pitch and 35° rotor tilt is 5.3 times more efficient than the baseline QBiT. The rotor-wing system is also simulated using CFD with the rotor at 58 different
This paper discusses the development of a fully-nonlinear flight dynamics model of a hover-capable Air-Launched Uncrewed Aerial System (ALUAS) in order to (1) understand the dynamics, controllability, and air loads of these type of aircraft while performing complicated maneuvers, (2) formulate design principles to feed back into the development of the realized physical aircraft, and (3) provide a high-fidelity dynamic framework to develop novel control laws. The flight dynamics model is developed using a software called Rotorcraft Comprehensive Analysis System (RCAS), where each component of the vehicle was modeled with varying fidelity. Wind tunnel tests were conducted on fullscale models to measure the forces and moments on the propeller, the isolated fuselage, and the full aircraft. Wind tunnel tests were also conducted to measure the forces and moments on the full aircraft for different wing folding angles. The thrust and torque of the propeller as well as the lift predictions for
Tailsitter configurations that operate in both fixed and rotary wing flight modes are typically capable of generating large control forces and moments, making them inherently capable of rapid transitions and aggressive maneuvers. However, harnessing these capabilities requires feedback control strategies that can effectively estimate the non-linear aerodynamics loads involved to successfully exploit them. This paper describes initial steps in combining an onboard flow sensing strategy with a data-driven approach to estimating inflight air loads. A neural network is trained to use measurements from a multi-hole probe to predict the output from a set of pressure sensors embedded in a wing section undergoing a series of pitch motions in a wind tunnel. We hypothesize that this limited context of emulating a sensor network represents a focused and compartmentalized approach to applying emerging data-driven techniques to challenging aeronautical problems. We compare estimation results from a
In the last decade, in order to respond to the emerging market of unmanned applications, Airbus Helicopters has developed a generic Flight Control System (FCS) for heavy unmanned helicopters. This paper describes the development of this system from the applicable high-level requirements to the design of the redundant fail safe-operative architecture and the flight modes. A focus is made on two specific flight sequences: Automatic Take-Off and Landing from ship deck which is one of the most complex maneuvers for a drone and 4D navigation (including relative to a target). The system has been brought to a maturity level with more than 100 flight hours in unmanned configuration and a level of Validation & Verification close to a certification. The portability of the developed solution on other helicopters to derive new Unmanned Aircraft Vehicle or Optionally Piloted Vehicle is also addressed thanks to commonalities with FCS that are already in use on the Airbus Helicopters fleet.
Launch, recovery, and deck handling operational performance on smaller ship platforms like Corvettes, Frigates and Destroyers are qualified as the most challenging tasks in the UAS ship-deployment of a VTOL Uncrewed Air System (UAS). One of the main hurdles is the random nature of seaway-created deck motions coupled with ship structure disturbed air wake patterns. The MoD has supported a range of work aimed at bringing Quiescent Period Prediction (QPP) technology to fruition. QPP firstly requires Wave Profiling RADAR to measure the sea wave system out to approximately 2km in the region around a vessel. Secondly these measurements are employed in a wave propagation model to predict the actual wave forces acting on a vessel. Using the wave predictions as inputs to a vessel model makes possible to predict the actual (deterministic as opposed to statistical) motions of a vessel. Wave systems naturally alternate groups of large waves with smaller waves, this property, combined with the
An unmanned aerial system automation qualities framework (previously known as the unmanned aerial system handling qualities framework) has been in development to determine a set of criteria and mission task elements for evaluating the airworthiness of unmanned aerial systems. The framework is being developed to apply across a range of unmanned aircraft from Group 1 to Group 4-5, via scalable predicted (quantitative) automation qualities metrics as well as scalable mission task elements. Prior work has developed scalable mission task elements and predictive attitude response criteria, scaled from MIL-DTL-32742 (which supersedes ADS-33E-PRF). This paper extends the UAS automation qualities framework to provide predictive (quantitative) criteria for velocity and position responses. The paper evaluates Froude scaled velocity disturbance rejection bandwidth and position disturbance rejection bandwidth requirements from MIL-DTL-32742 and describes and evaluates two new metrics, velocity
The Shake-The-Box technique was applied to experimentally quantify the time-resolved volumetric flow field around a free-flying quadcopter UAV with an overall span of about 0.5 m. State-of-the-art LED illumination and high-speed camera equipment was combined with modern Lagrangian tracer particle tracking and data assimilation techniques, facilitating a measurement volume larger than 1.5m3. The setup allowed for both hover and limited maneuvering of the quadcopter, while resolving even small details of the complex interactional aerodynamics. In hover out of ground effect, the four individual rotor wakes merged into a single jet within a few rotor radii below the rotor planes. Evaluating the mass and momentum fluxes over suitable control volumes yields accurate estimates for the quadcopter's total thrust, the asymmetric thrust distribution between front and back rotors, and the entrainment of external flow through turbulent mixing. Hover in ground effect decreases the power requirement
Manual analysis of the aerodynamic behavior of small unmanned aircraft is a lengthy and repetitive task. This paper shows the current state of an automated flight analysis tool that calculates the aerodynamic coefficients of small unmanned aerial vehicles. It covers the tool's workflow, shows the current quality of the data processing, and lessons learned. It compares the results of different aircraft types, including standard electric motor and glider aircraft, and shows specifically designed and tested flight patterns. The results of the tool are compared to manually computed data from the glider using a low-wind flight before sunrise. Finally, the impact of thermals on the measured data is presented. An outlook will show the remaining limitations and possible future additions to the tool.
This paper presents a path planning concept based on the Manned-Unmanned Teaming (MUM-T) between the helicopter and a drone. The drone flies ahead of the helicopter to detect possible unexpected obstacles in the mission area and sends the data to the helicopter. The path of the helicopter is automatically replanned to avoid the meteorological and physical obstacles detected by the drone. The path planning is based on the Rapidly-exploring Random Tree* (RRT*) and the Bidirectional Rapidly-exploring Random Tree (BiRRT) algorithms. The reference trajectory is planned by means of the RRT* algorithm and the replanning is performed with the BiRRT. The node connection is realized with the Dubins curves, that force the path to comply with the prescribed limitations on the helicopter's roll angle and flight path angle. The Savitzky-Golay filter is used to smooth the trajectory achieving curvature continuity. A closed-loop simulation model containing the dynamics of the pilot is used to evaluate
This paper explores the conceptual design and proof-of-concept demonstration of an unmanned rotary wing Unmanned Aerial Vehicle (UAV) for logistics at high altitude areas. An iterative design methodology is developed using sizing formulas to carry out trade-off study for conceptual design of an unmanned helicopter based on the specified mission requirements. The key mission scenario involves taking off with 25 kg payload at an altitude of 5500 meters above mean sea level (AMSL), climbing 500 m above ground level (AGL), cruising to the delivery target, dropping of the payload while hovering, returning, and descending 500 meters for final landing. Two distinct mission profiles are explored for design: one with a total hover endurance of 40 minutes and the other with complete mission comprising of takeoff, climb, cruise, descent and landing. The methodology employed evaluates key design factors, including component weight allocation using empirical approaches. Hover Out of Ground Effect
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