Flight Model Research Articles

Optimized levy flight model for heart disease prediction using CNN framework in big data application

Cardiac disease is one of the most complex diseases globally. It affects the lives of humans critically. It is essential for accurate and timely diagnosis to treat heart failure and prevent the disease. In most aspects, it was not so successful with the traditional method, which uses past medical history. Many existing models had several types of the loss function in traditional CNN can lead to misidentification of the model. To solve this problem, so many scholars have used the swarm intelligence algorithm, but most of these techniques are stuck in the local minima and suffer from premature convergence. In the proposed method, we build up the Levy Flight – Convolutional Neural Network (LV-CNN) depending on the diagnostic system using heart disease image data set for heart disease assessment. Initially, the input Big Data images are resized to reduce the computational complexity of the system. Then, those resized images are subject to the proposed LV-CNN model. Therefore, the LV approach is integrated with the Sunflower Optimization Algorithm (SFO) to reduce loss function occurring in the CNN architecture. Such a combination helps the SFO algorithm avoid trapping in local minima due to the random walk of the levy flight. The proposed algorithm will be simulated using the MATLAB tool and tested experimentally in terms of accuracy is 95.74%, specificity is 0.96%, the error rate is 0.35, and time consumption is 9.71 s. This comparative analysis revealed that the excellence of the proposed model.

Flight Performance and Dispersion Analysis for a Flexible Tactical Missile

To deliver heavier payloads to longer ranges as the main objective of tactical missiles, higher slenderness and thrust-to-weight ratios are sought. This leads to the emergence of aeroelasticity, which can impact the accuracy of guided missiles and the accuracy and dispersion of unguided ones. The present study aims at exploring the effect of aeroelasticity on flight, dispersion, and accuracy of a case study tactical missile with about a 16.5 slenderness ratio. A framework is developed involving a flexible missile trajectory via -degree-of-freedom flight modeling, vibration characteristics estimation via the Euler–Bernoulli (EB) beam theory, aerodynamic characteristics estimation, and Monte Carlo simulation. Experiments are conducted to validate the EB theory and the aerodynamic model. A parametric study of the impact of missile flexibility and the roll rate on aeroelastic performance is conducted. The results show that missile deflection depends on the first bending frequency, and the static stability margin differs from that of the rigid one. It is also confirmed that aeroelastic divergence is introduced through the boosting phase. As the roll rate is introduced, higher aerodynamic frequency (and hence higher aerodynamic loads) is attained. Increasing the elasticity slightly reduces the missile downrange and yields precision improvement. Overall, the dynamic stability of the flexible missile increases as compared to that of the rigid case.

Development and Calibration of a Three-Directional High-Energy Particle Detector for FY-3E Satellite

According to the characteristics of the LEO space particles radiation environment of China’s Fengyun No. 3 (FY-3) polar-orbiting meteorological satellites, in order to monitor the characteristics, and space–time distribution of charged particle radiation in the orbit space, it is proposed to install a three-directional high-energy particle detector (HEPD) in the three vertical orthogonal directions of FY-3E, so as to carry out the energy spectrum and flux observation of high-energy protons and electrons in the three directions of the satellite, namely, −X, +Y, and −Z. The on-orbit detection data acquired by these payloads can be used for space environment modeling and solar-terrestrial physics research, and provide data sources for operational space environment weather warning and forecasting. Through the ground accelerator calibration experiment and simulation analysis of the three-directional HEPDs developed in the flight model phase, the experimental results show that all the HEPDs’ measured values meet the requirements for technical indexes, such as the detection energy range (high-energy protons: 3–300 MeV; high-energy electrons: 0.15–5.7 MeV), energy span accuracy (<15%), flux accuracy (<15%), and sensitivity (<5% (ΔN/N)).

Flyrock in surface mining - Limitations of current predictive models and a better alterative through modelling the aerodynamics of flyrock trajectory

Historical approaches to the problem of flyrock based on correlation studies and regression analysis, including artificial neural networks and similar techniques, are inherently incapable of addressing two core issues - root causes of flyrock and projection velocity. A further shortcoming of correlation techniques is that they give no information on the influence of rock size and shape on the flight distance. The scaled depth of burial model for crater blasting in the collar zone and bench face does not specifically address the question of flyrock velocity. A third approach, based on flight trajectory calculations, often neglects the very significant effects of air resistance on the trajectory. Some trajectory models incorporate air resistance but use an implausible fragment velocity model that cannot propel sizeable rocks to distances much beyond 150 m. Nonetheless, trajectory calculation incorporating the effects of air drag affords the most promising approach to the prediction of flyrock range. A unique and insightful feature of the proposed realistic flight modelling is that it collapses all suspected causes of flyrock, many of which are not well understood, to just a single parameter - the launch velocity. This indicates that the root causes of flyrock lie in the mechanisms of momentum transfer to broken rock and suggests new avenues of study.

Life Cycle Assessment of the Cellulosic Jet Fuel Derived from Agriculture Residue

The purpose of this paper is to discover the impacts of contradictory factors in the application of agricultural residue with sustainable biofuel benefits. Based on the Life cycle assessment (LCA) approach, the quantitative LCA assessment model and approach have been established, coupling upstream cultivation and downstream jet biofuel product, which would benefit agriculture residue choice. The LCA model investigated the effects of interaction factors on energy consumption, including land release and agriculture residue use change. The computational framework of the LCA model is classified into three sub-models, including the cultivation and harvesting model, the refining process and distribution model, and the flight model. According to uncertainty analysis by the LCA model, the positive energy gains have been conducted at a wide range of hydrogen production and methanol production. The application model is represented by six types of typical aircraft widely used in China, including the LTO cycle module, actual cruising distance and maximum cruising distance module, actual payload, and maximum payload module. In the whole life cycle assessment, GHGs of agriculture residue is 17.9 gCO2e/MJ while petroleum-based jet fuel is 90.2 gCO2e/MJ. The order of GHGs in WTW (well to wheel) is agriculture residue < corn stover < beanstalk < wheat straw < rice straw. The land release conducted obviously to the total GHGs emission for rice straw, which indicated that land release should involve in the LCA.

Airflow characteristics of rotorcraft plant protection UAV operating in rice fields

Rotorcraft unmanned aerial vehicles (UAVs) cause movement of the rice crop which is an important indicator of the effectiveness of spray applications. A method of acquiring images of the effects of airflow on the spray target by video aerial photography and computer vision to process the images was examined to obtain the characteristic information in rice fields; the dimensions of the disturbed area of crop, the so-called “rice vortex”. Orthogonal experiments were designed to investigate the three factors of take-off mass, flying height and flight speed of the plant protection to assess the four indices of trailing distance, trailing stability, area and shape of the rice vortex. The results show that the influence of the three factors on the vortex trailing distance and its stability was in the order of flight speed, flight altitude and take-off mass. The effects on the vortex area and vortex shape were speed > mass > height. Analysis and discussion of the characteristics and morphological features of the airflow targets revealed that the greater the distance and longer the duration of the trailing vortex, the more easily the rice vortex was disturbed and dissipated, and the lower its stability. Changes in the shape of the rice vortex mainly occur in its length, and changes in width are smaller. The results provide a data collection method and basis for further development of flight parameter-airflow target-application effect models. The four parameters of the trailing distance, stability, vortex area, and vortex shape constitute technical parameters suitable for assessing the effects of rotorcraft plant protection UAVs operating in rice fields.

Bird-inspired robotics principles as a framework for developing smart aerospace materials

Birds are notable for their ability to seamlessly transition between different locomotory functions by dynamically leveraging their shape-shifting morphology. In contrast, the performance of aerial vehicles is constrained to a narrow flight envelope. To understand which functional morphological principles enable birds to successfully adapt to complex environments on the wing, engineers have started to develop biomimetic models of bird morphing flight, perching, aerial grasping and dynamic pursuit. These studies show how avian morphological capabilities are enabled by the biomaterial properties that make up their multifunctional biomechanical structures. The hierarchical structural design includes concepts like lightweight skeletons actuated by distributed muscles that shapeshift the body, informed by embedded sensing, combined with a soft streamlined external surface composed of thousands of overlapping feathers. In aerospace engineering, these functions are best replicated by smart materials, including composites, that incorporate sensing, actuation, communication, and computation. Here we provide a review of recently developed biohybrid, biomimetic, and bioinspired robot structural design principles. To inspire integrative smart material design, we first synthesize the new principles into an aerial robot concept to translate it into its aircraft equivalent. Promising aerospace applications include multifunctional morphing wing structures composed out of smart composites with embedded sensing, artificial muscles for robotic actuation, and fast actuating compliant structures with integrated sensors. The potential benefits of developing and mass-manufacturing these materials for future aerial robots and aircraft include improving flight performance, mission scope, and environmental resilience.

TA-LSTM: A Time and Attribute Aware LSTM for Deep Flight Track Clustering

The rapid development of civil aviation imposes an urgent need for efficient air traffic management. Flight track clustering is the premise and foundation of air traffic control. Flight track points compose time-series data with non-identical point- to-point intervals, and the effective latent representation of track data is key to the flight trajectory clustering. Long Short-Term Memory (LSTM) is an important and popular method to extract the features of trajectory time-series data. However, LSTM ignores the irregular time intervals between track points and fails to effectively distinguish the importance of different attributes at each track point during feature extraction. In addition, the existing methods based on LSTM either ignore the distinct impacts of different attributes at each track point or simply assume that the influences of the previous track points on the subsequent ones decrease with time. In this paper, we propose a flight trajectory feature extraction unit called TA-LSTM (Time and Attribute Aware Long Short- Term Memory) and a flight track clustering model based on TA- LSTM. The flight track clustering model consists of a feature extraction layer and a clustering layer. The feature extraction layer adopts TA-LSTM to obtain the latent representation of flight tracks, which adds a time control gate and an attribute control gate to the standard LSTM unit. The time control gate manipulates the action of each track point on subsequent points to obtain the characteristics of irregular time intervals. The attribute control gat enables LSTM to capture the impact of different attributes on the flight track features at various points. The clustering layer takes the latent representation of flight tracks as the input to obtain the clustering results. The clustering model updates the parameters of TA-LSTM and the cluster centers by minimizing the Kullback-Leibler (K-L) divergence. We conduct experiments using Automatic Dependent Surveillance-Broadcast track data provided by VariFlight. In comparison with popular and state-of-the-art methods, the proposed method obtains superior pe formance in three widely used evaluation metrics, i.e., Silhouette Coefficient, Calinski-Harabaz index and Davies-Bouldin index.

Creation of a Z 43 aeroplane model for a flight simulator

This paper describes the process of developing a Zlin Z 43 aircraft for a flight simulator. Work on an aircraft simulation consists of multiple parts. The development of the flight model is the first and core part of the simulation. Work on this part consisted of an analysis of the X-Plane blade element theory-based flight model, sourcing of the data this model requires, flight testing and further editing of the data to match the known performance of the Zlín Z43. The aircraft systems are another core part of the simulation. A Mix of the simulator's default, customised and fully custom systems are used. The theory and process of creating, animating, and texturing a 3D model are described, too. Visual quality can also be important, especially for its use in virtual reality. The last part is about the user interface, user experience and how the various use cases shape their design for an aircraft simulation.

On One Problem of Controlling an Airplane-type Unmanned Aerial Vehicle with Given Intermediate Values of Different Parts of Coordinates

The mathematical model of spatial flight of an unmanned airplane-type vehicle is considered. For a linearized mathematical model of an unmanned aerial vehicle the problem of synthesis of control laws with given initial, finite values of the phase vector and intermediate values of different parts of coordinates at different moments of time is solved. A necessary and sufficient condition for the existence of program control and the corresponding motion is formulated. The control functions and corresponding phase trajectories of motion are constructed. As an application of the proposed approach, explicit expressions of the program control function and program motion are constructed for specific numerical values.

МАТЕМАТИЧНА МОДЕЛЬ ПОЛЬОТУ СНАРЯДА ЯК МОДИФІКОВАНА МОДЕЛЬ МАТЕРІАЛЬНОЇ ТОЧКИ У ЯВНІЙ ФОРМІ

A promising direction for improving the accuracy and operational efficiency of firing artillery systems is the development of ballistic computers that implement procedures for determining settings using the solution of a system of differential equations (mathematical model) that describe the movement of a projectile in the air. The main problem in the development of mathematical models is the possibility of determining with a given accuracy the coefficients of aerodynamic forces (moments) that are in the right-hand sides of differential equations. An urgent issue in this direction is the study of the possibility of restoring the coefficients of aerodynamic forces (moments) by solving the inverse problem of external ballistics using mathematical models of projectile flight. The movement of projectiles is usually described using one of three mathematical models, which differ from each other in the main level of complexity and, accordingly, the level of adequacy to the real process of projectile movement in the air. Therefore, the complexity of recovery procedures is determined by the number of coefficients of aerodynamic forces (moments) and differential equations included in mathematical models. A modified model of a material point is presented as a mathematical model of projectile flight in which all aerodynamic forces are taken into account, the orientation of the projectile is characterized by taking into account the nutation angle, and the kinetic energy of the rotational movement is taken into account through the angular velocity of the projectile around its axis of symmetry. It is shown that the modified material point model is determined by adding an implicit ordinary differential equation - an equation that describes the nutational oscillations of the projectile, which depend on the acceleration of its flight. Procedures for converting the system of differential equations of the modified material point model to an explicit form are disclosed, which allows them to be solved on the basis of standard numerical methods.

Bench satellite development and testing

This paper discusses the development of a satellite-like system to bridge the gap between satellite development and satellite flight missions. The solution takes the form of a bench satellite, BenchSat, that can emulate satellite capabilities and interactions in a controlled environment on the ground. BenchSat utilises surrounding facilities, particularly an air bearing facility and an existing ground station, to produce a realistic test environment for satellite development. The air bearing facility entails a cart with pressurised gas which pushes the cart on a flat surface, creating a low-friction, space like environment. BenchSat comprises an electrical power subsystem, a radio communication subsystem, and an onboard computer subsystem. These systems are created to be a good representation of equivalent flight models and can serve as an initial step in the future development of each of these subsystems. A final experiment was conducted using an integrated BenchSat connected to an air bearing carrier cart. The ground station was used to give commands to the BenchSat to use its thrusters to translate and rotate the carrier cart. This creates a realistic interface to perform satellite rendezvous experiments. It is further extended to interface with a satellite simulator for Hardware-In-Loop testing and flight software development.

Experimental studies of linear quadratic regulator (LQR) cost matrices weighting to control an accurate take-off position of bicopter unmanned aerial vehicles (UAVs)

Controller design for airplane flight control is challenged to achieve an optimum result, particularly for safety purposes. The experiment evaluated the linear quadratic regulator (LQR) method to research the optimal gain of proportional-integral-derivative (PID) to hover accurately the bicopter model by minimizing error. The 3 degree of freedom (DOF) helicopter facility is a suitable bicopter experimental simulator to test its complex multiple input multiple output (MIMO) flight control model to respond to the challenge of multipurpose drone control strategies. The art of LQR setting is how to search for appropriate cost matrices scaling to optimize results. This study aims to accurately optimize take-off position control of the bicopter model by investigating LQR cost matrices variation in actual experiments. From the experimental results of weighted matrix variation on the bicopter simulator, the proposed LQR method has been successfully applied to achieve asymptotic stability of roll angle, although it yielded a significant overshoot. Moreover, the overshoot errors had good linearity to weighting variation. Despite that, the implementation of cost matrices is limited in the real bicopter experiment, and there are appropriate values for achieving an optimal accuracy. Moreover, the unstable step response of the controlled angle occurred because of excessive weighting.

A Method to Measure and Model Acoustic Emissions of Multicopters.

There is a growing interest for commercial applications of Unmanned Aerial Vehicles, but important foundations for an assessment, among others about noise, are missing. This contribution specifically focuses on a method to measure and model the sound radiation of multicopters. The emission prediction is hereby based on measurements using a multiple regression approach. An important finding is that the directivity pattern is widely independent of the rotational speed of the rotors and of the flight procedure. Consequently, the directivity pattern can be determined for a stationary hover flight, which considerably simplifies the measurement procedure. In addition to a rotational speed-dependent sound emission model for hover flight, a multicopter-specific correction term is required to account for forward flight. The validity of this approach is demonstrated based on the field measurements of three different multicopter models.

Formal Safety Envelopes for Provably Accurate State Classification by Data-Driven Flight Models

Aerospace systems are inherently stochastic and increasingly data-driven, thus hard to formally verify. Data-driven statistical models can be used to estimate the state and classify potentially anomalous conditions of aerospace systems from multiple heterogeneous sensors with high accuracy. In this paper, we consider the problem of precisely bounding the regions in the sensor input space of a stochastic system in which safe state classification can be formally proven. As an archetypal application, we consider a statistical model created to detect aerodynamic stall in a prototype wing retrofitted with piezoelectric sensors and used to generate data in a wind tunnel for different flight states. We formally define safety envelopes as regions parameterized by and , to respectively capture how model-predictable observed sensor values are, and given these values, how likely the model’s accurate state classification is. Safety envelopes are formalized in the Agda proof assistant, used to also generate formally verified runtime monitors for sensor data stream analyses in the Haskell programming language. We further propose a new metric for model classification quality, evaluate it on our wing prototype model, and compare it to the model restricted to two different fixed airspeeds, and enhanced to a continuous Gaussian process regression model. Safety envelopes are an important step in formally verifying precise probabilistic properties of data-driven models used in stochastic aerospace systems and could be used by advanced control algorithms to maintain these systems well within safe operation boundaries.

Manufacturing and testing of AMaSED-2: a no-insulation high-temperature superconducting demonstrator coil for the space spectrometer ARCOS

The Astroparticle Research Compact Orbital Spectrometer (ARCOS) magnet is a 12-coil toroidal magnet for a proposed next-generation magnetic spectrometer in space. AMaSED-2 is a small-scale non-flight demonstrator coil for the ARCOS magnet. AMaSED-2 consists of two individually built no-insulation high-temperature superconducting pancake coils with racetrack-like shapes. The two pancake coils are contained in a total of of wide SuperPower REBCO HTS tape. Copper bands functioning as current leads and layer jump surround the winding blocks. An aluminum structure mechanically supports the coil assemblies. AMaSED-2 was manufactured and tested at CERN. The coil was tested in cryogenic helium gas at various temperatures between and by measuring the center magnetic flux density while varying the operating current. We employ a model for no-insulation coils and identify for each temperature the center magnet constant and magnet charging time constant as system parameters. We also determine the radial resistance, peak magnet constant, magnet critical current, and maximum achieved magnetic flux densities. Central magnetic flux densities up to were measured, corresponding to a peak magnetic flux density on the coil of . The design and characterization of AMaSED-2 provides a basis for future magnet development of a flight model.

Flight Time Optimization and Modeling of a Hybrid Gasoline–Electric Multirotor Drone: An Experimental Study

Drones have evolved rapidly over the decades, but the limited flight time inhibits multirotor drones from performing long-duration tasks. Batteries that power drones are considered an inadequate power source due to their low energy density. As gasoline is an energy-dense source, combining an electric propulsion system with gasoline engines should be considered. This paper proposes a novel hybrid multirotor drone design using two gasoline engines to provide the majority of the lift force and four electric motors to stabilize the drone. These propulsion systems have been characterized and optimized to exploit their respective advantages, which reduce the total energy consumption rate and increase flight time. Simulation and experimental results show that the hybrid gas–electric multirotor drone can achieve more than three times the flight time of the fully electric drone.

Analysis of problems of small-angle approximation in mathematical models of projectile flight

The article deals with the topical issue of developing mathematical models of projectile flight, which accurately describe the projectile motion in the air. It is shown that the nature of the mathematical models presentation varies depending on the required reliability degree of the real physical projectile flight process representation by the mathematical model, the adequate consideration of certain forces (moments) acting on the projectile, as well as the level of information about the external flight conditions which include the parameters of the air in which the projectile moves.At the same time, the use of the shape coefficient - the agreement coefficient in the differential equation system leads to "rough" mathematical models, which does not allow to adequately describe the projectile flight trajectory and its individual elements. The solution to this problem is especially relevant during developing and implementing procedures, technical solutions in the interest of achieving the necessary level of interoperability with NATO forces, the gradual abandonment of the standard functions of air resistance, the transition to individual functions and mathematical models of projectile motion, which are currently accepted in the member states of the Alliance. The conducted analysis of modern mathematical models showed that their construction is based on an approximate approach, which was called the small-angle approximation, in which, for an axisymmetric rotating projectile, it is considered that the nutation angles are sufficiently small, the aerodynamic forces (moments) depend only on the speed of its flight and the nutation angle, and only the linear terms of their Taylor series expansion are used in the calculations. The nutation-precessional behavior of the projectile was considered and the nonlinear dependencies of the coefficients of the aerodynamic forces (moments) of the projectile on the angles of nutation were revealed.

System Modeling and Artificial Neural Network (ANN) Design for Lateral and Longitudinal of F-16

Today, the classical control methods are still widely used because of their excellent performance in a working environment with conditions of geo-graphical distance. They are suitable for functions of the system: more flexible operating system, easy to perform, less unwanted ricks occur, the efficiency of controlling a system better. Besides the traditional control methods, the author has applied more modern and smarter algorithms such as artificial intelligence to control a system on the ground or a system moving in the air. In this paper, artificial neural network (ANN) is applied for a flight model to demonstrate its effectiveness in all cases. ANN in this article to show off its amazing application for flying devices. This is a useful method because it is highly secure. Simulation is done by Matlab.

Calibration and Verification of Pointing and Tracking System for Optical Communication Terminal

This paper presents the experimental verification of the pointing and tracking system of the flight model of an optical communication terminal for small satellites. The terminal, called LaserCube, fits in two CubeSat units and is conceived to operate onboard spacecraft starting from the 6 U (CubeSat units) form factor. The terminal is provided with a dual stage pointing system, composed of a coarse pointing mechanism used to orient the optical head and a fast-steering mirror for the fine pointing of the received and transmitted lasers. The coarse pointing mechanism is based on the parallel platform configuration and alone can provide rms pointing accuracy when operating in conjunction with a beacon laser sent by a remote terminal and used for feedback. The control algorithm operates the two pointing stages synergically, targeting an overall pointing accuracy of rms while rejecting the disturbances coming from the satellite bus. The pointing system of the LaserCube flight model has been calibrated and experimentally verified in laboratory conditions that replicate real operational scenarios for what concerns the beacon signal attenuation and the disturbances generated by the host satellite. A dedicated setup was used to directly measure the pointing error and asses the system performance.