Precise Flight Research Articles

Wing-strain-based flight control of flapping-wing drones through reinforcement learning

Although drone technology has advanced rapidly, replicating the dynamic control and wind-sensing abilities of biological flight is still beyond reach. Biological studies reveal that insect wings are equipped with mechanoreceptors known as campaniform sensilla, which detect complex aerodynamic loads critical for flight agility. By leveraging robotic experiments designed to mimic these biological systems, we confirm that wing strain provides crucial information about the drone’s attitude angle, as well as the direction and velocity of the wind. We introduce a wing-strain-based flight controller that employs the aerodynamic forces exerted on a flapping drone’s wings to deduce vital flight data such as attitude and airflow without accelerometers and gyroscopic sensors. The present work spans five key experiments: initial validation of the wing strain sensor system for state information provision, control in a single degree of freedom movement environment with changing winds, control in a two degrees of freedom movement environment for gravitational attitude adjustment, a test for position control in windy conditions and a demonstration of precise flight path manipulation in a windless condition using only wing strain sensors. We have successfully demonstrated control of a flapping drone in various environments using only wing strain sensors, with the aid of a reinforcement-learning-driven flight controller. The demonstrated adaptability to environmental shifts will be beneficial across varied applications, from gust resistance to wind-assisted flight for autonomous flying robots.

Three-Dimensional Spatial Atmospheric Turbulence Generation Method for Aerial Refueling Flight Simulation

Traditional flight simulation models often operate on the premise of a steady atmosphere, overlooking the complexities of actual atmospheric dynamics and the flight safety risks posed by wind disturbances, such as turbulence. To Address this oversight, the present study introduces a method for generating three-dimensional atmospheric turbulence based on spatial correlation functions. This method, rigorously validated against correlation and spectral benchmarks, guarantees isotropic properties in the synthesized turbulence fields. Through interpolation techniques, the model integrates the spatial atmospheric turbulence into the flight simulation framework effectively. The paper highlights the application of this model by examining the impact of atmospheric turbulence on the precise flight dynamics of quadcopter UAVs during aerial refueling operations. The findings demonstrate the model’s pertinence not only to UAVs but also to the broader spectrum of aircraft and their operational procedures.

Learning Hybrid Policies for MPC with Application to Drone Flight in Unknown Dynamic Environments

In recent years, drones have found increased applications in a wide array of real-world tasks. Model predictive control (MPC) has emerged as a practical method for drone flight control, owing to its robustness against modeling errors/uncertainties and external disturbances. However, MPC’s sensitivity to manually tuned parameters can lead to rapid performance degradation when faced with unknown environmental dynamics. This paper addresses the challenge of controlling a drone as it traverses a swinging gate characterized by unknown dynamics. This paper introduces a parameterized MPC approach named hyMPC that leverages high-level decision variables to adapt to uncertain environmental conditions. To derive these decision variables, a novel policy search framework aimed at training a high-level Gaussian policy is presented. Subsequently, we harness the power of neural network policies, trained on data gathered through the repeated execution of the Gaussian policy, to provide real-time decision variables. The effectiveness of hyMPC is validated through numerical simulations, achieving a 100% success rate in 20 drone flight tests traversing a swinging gate, demonstrating its capability to achieve safe and precise flight with limited prior knowledge of environmental dynamics.

Identifying Implementation Strategies for Integrating Drones into STEM and Career Technology Education CTE Programs

As drone technology is rapidly becoming accessible to school children in terms of both low cost and ease-of-use, primary and secondary school teachers are beginning to consider where modern drones can play an important role in schooling. To date, there is little empirical education research printed in the education research literature guiding innovative curriculum developers in the incipient domain of drone education. As a result, teachers interested in including emerging technologies in their classrooms are often at a loss of where to begin. Through clinical interviews with schoolteachers in the United States, our study identified five readily accessible “departure points” to include drones in contemporary STEM and vocational technology (CTE) school classrooms that help teachers address common curricular goals. Taken together, these interviews reveal that teachers using drones follow one of several distinct pathways as a first step toward achieving a widespread goal of teaching students to use modern technologies to construct, pursue, and communicate findings of fruitful research inquiries—the prevalence of which is not reflected in a comprehensive review of the literature. The five dominant pathways for starting a successful drone education emerging from the interview data were as follows: timed racing trials; precision flight obstacle courses; computer coding; videography; and domain-specific knowledge of drone operation laws and ethics.

Matlab sımulatıon of quadcopter dynamıcs and PID attıtude controller

Due to the ever-growing popularity of quadcopters, they are used in various fields such as surveillance, military, surveillance and courier services and are of great importance. Ideal handling of quadcopters is essential for safe maneuvering and high precision flight performance. This research provides simulation of quadcopter control in MATLAB software, development and review of various control principles.
 Dynamic development in unmanned aerial vehicles (UAVs) has led to the rapid spread of quadcopters in many fields, from airspace control to courier services. This research study investigates the Proportional-Integral-Derivative (PID) attitude controller by simulating the quadcopter dynamic object in MATLAB software. The heart of this research is to create and develop a PID attitude controller, which is a critical component for accurate control of quadcopter.

Optimized fuel values for emission reduction

Aviation is an integral and vital part of modern society. The growth over the last decades has consequences for greenhouse gas emissions and reducing this through efficiency within the same framework is difficult. Precision flight planning is crucial for reliably and optimized real environment aircraft operation. The presented study gives an overview of the status of the legal requirements for flight planning under the current fuel requirements of the European Union Aviation Safety Agency (EASA) and the emerging opportunities for fuel savings. As part of the larger study, planned and actual fuel figures of an international cargo airline were statistically analyzed. The overall analysis showed that there was no significant deviation between planned and consumed fuel. Based on the results, an adjustment of the planned alternative fuel quantity can be considered within the framework of an individual fuel plan. The possible savings potential using the example of Destination Alternate Airport fuel is presented.

PWM Precision Flight Controller Cooling System for UAV in Pineapple Plantation

PWM selection is to provide the required operating signal for the flight controller. During the flight, drone technology advances, flight times and distances escalate. The flight controller will become more susceptible to damage, complicating the distance and tasks that the drone will perform—the likelihood of causing high maintenance costs. The appropriate PWM to maintain the cooling system, safeguard to extensive usage of operating signal might be useful to minimize mechanical damage and extend flight longevity. The aim is to develop a cooling system to subside thermal heat in order to raise a UAV's flight time. The study was carried out in a closed environment with room temperature at 32ºC. A flight controller prototype was designed and operated with PWM, and fan revolution speed with temperature was recorded every 15 seconds for 1 minute. The thermal heat reduces by 6ºC from the baseline (40ºC), the fan speed remains constant at 3000-3500 rpm at 45-60 secs during PWM 25%. Whereby, thermal heat reduces by 10ºC from the baseline, the fan speed remains 4000 -5000 rpm at 45-60 secs during PWM 75%,100%. The linearity between the duty cycle of PWM is 98% with fan speed. However, the appropriate duty cycle of PWM set at 50%; the temperature is considerably below 30ºC beginning at 45 secs shows positivity towards cooling systems. Thus, the operating signal is overused during PWM 75% and 100% for 15 secs. The basic concept behind this project is to turn on the DC motor fan when the temperature threshold value of 40ºC.

Minimum Energy Control of Quadrotor UAV: Synthesis and Performance Analysis of Control System with Neurobiologically Inspired Intelligent Controller (BELBIC)

There is a strong trend in the development of control systems for multi-rotor unmanned aerial vehicles (UAVs), where minimization of a control signal effort is conducted to extend the flight time. The aim of this article is to shed light on the problem of shaping control signals in terms of energy-optimal flights. The synthesis of a UAV autonomous control system with a brain emotional learning based intelligent controller (BELBIC) is presented. The BELBIC, based on information from the feedback loop of the reference signal tracking system, shows a high learning ability to develop an appropriate control action with low computational complexity. This extends the capabilities of commonly used fixed-value proportional–integral–derivative controllers in a simple but efficient manner. The problem of controller tuning is treated here as a problem of optimization of the cost function expressing control signal effort and maximum precision flight. The article introduces several techniques (bio-inspired metaheuristics) that allow for quick self-tuning of the controller parameters. The performance of the system is comprehensively analyzed based on results of the experiments conducted for the quadrotor model.

LANDSLIDE SURVEYS USING LOW-COST UAV AND FOSS PHOTOGRAMMETRIC WORKFLOW

Abstract. Unmanned Aerial Vehicle have found their usage in various academic and industry domains, mainly due to the versatility of options that one aircraft can offer from onboard sensors for data acquisition and positioning, through different weight and size categories allowing different applications, including landslide mapping and surveying. Survey-grade UAVs can provide very precise flight and data but usually are very costly, and their use can be further bounded by many regulations. In this work, we have adopted a low-cost consumer-grade UAV to do multitemporal monitoring of an active landslide (Ruinon) in Northern Italy to evaluate the applicability of such setup in the landslide hazard domain. Moreover, for flight planning, photogrammetric reconstruction, and comparative analyses we have adopted free and open-source software solutions. The resulted dense point clouds and orthophotos yielded very satisfactory results from accuracies of few meters and even sub-meter level when reconstructed with field-surveyed ground control points. As a result, from the two surveys comparisons, July and October 2021, several displaced boulders and debris were detected where no significant reactivations were detected from our surveys. Such low-cost setup can be used also from non-professionals and in citizen science campaigns which can significantly contribute to additional landslide mapping and analyses by providing valuable datasets.

Neural-Fly enables rapid learning for agile flight in strong winds.

Executing safe and precise flight maneuvers in dynamic high-speed winds is important for the ongoing commoditization of uninhabited aerial vehicles (UAVs). However, because the relationship between various wind conditions and its effect on aircraft maneuverability is not well understood, it is challenging to design effective robot controllers using traditional control design methods. We present Neural-Fly, a learning-based approach that allows rapid online adaptation by incorporating pretrained representations through deep learning. Neural-Fly builds on two key observations that aerodynamics in different wind conditions share a common representation and that the wind-specific part lies in a low-dimensional space. To that end, Neural-Fly uses a proposed learning algorithm, domain adversarially invariant meta-learning (DAIML), to learn the shared representation, only using 12 minutes of flight data. With the learned representation as a basis, Neural-Fly then uses a composite adaptation law to update a set of linear coefficients for mixing the basis elements. When evaluated under challenging wind conditions generated with the Caltech Real Weather Wind Tunnel, with wind speeds up to 43.6 kilometers/hour (12.1 meters/second), Neural-Fly achieves precise flight control with substantially smaller tracking error than stateof-the-art nonlinear and adaptive controllers. In addition to strong empirical performance, the exponential stability of Neural-Fly results in robustness guarantees. Last, our control design extrapolates to unseen wind conditions, is shown to be effective for outdoor flights with only onboard sensors, and can transfer across drones with minimal performance degradation.

An effort saving method to establish global aerodynamic model using CFD

Purpose The typical approach of modeling the aerodynamics of an aircraft is to develop a complete database through testing or computational fluid dynamics (CFD). The database will be huge if it has a reasonable resolution and requires an unacceptable CFD effort during the conceptional design. Therefore, this paper aims to reduce the computing effort required via establishing a general aerodynamic model that needs minor parameters. Design/methodology/approach The model structure was a preconfigured polynomial model, and the parameters were estimated with a recursive method to further reduce the calculation effort. To uniformly disperse the sample points through each step, a unique recursive sampling method based on a Voronoi diagram was presented. In addition, a multivariate orthogonal function approach was used. Findings A case study of a flying wing aircraft demonstrated that generating a model with acceptable precision (0.01 absolute error or 5% relative error) costs only 1/54 of the cost of creating a database. A series of six degrees of freedom flight simulations shows that the model’s prediction was accurate. Originality/value This method proposed a new way to simplify the model and recursive sampling. It is a low-cost way of obtaining high-fidelity models during primary design, allowing for more precise flight dynamics analysis.

An ultra-high-resolution autonomous uncrewed helicopter aeromagnetic survey in Izu-Oshima Island, Japan

We conducted a high-resolution aeromagnetic survey using an autonomously driven uncrewed helicopter that flew as low as several tens of meters above the ground along precise flight tracks with 1 m accuracy. The geomagnetic total intensity was measured by a total intensity magnetometer suspended beneath the helicopter at a ~ 50 m or less flight spacing over the entire caldera of Mt. Mihara, located on Izu-Oshima Island, Japan. From the observed geomagnetic data, we estimated high-resolution subsurface magnetization intensity. A high average magnetization intensity of 13.5 A/m was obtained for the entire caldera. The distribution of the magnetization intensity was not only consistent with the results of conventional airborne surveys, but it also had a high spatial resolution of less than 100 m. Highly magnetized areas were observed along the NW–SE lines that intersected the summit pit crater, Crater A, which is consistent with the principal stress direction of Izu-Oshima Island. These highly magnetized areas might be solidified magma that did not reach the surface during past eruptions. A large and deep-rooted weakly magnetized area was found just outside of the NE side of the central cone, which corresponds to the location of Fissure B, and the conduit must have been demagnetized at the previous event. Other weakly magnetized areas were also observed at the N, E, and SW sides around the pit crater. These regions correspond to the location of fumaroles in the crater. The high-resolution subsurface magnetization imaged by the autonomous uncrewed helicopter will be helpful for the mitigation of future eruption damage by enabling the assessment of potential fissure eruption areas.

Performance analysis and design of loitering munitions: A comprehensive technical survey of recent developments

Loitering munitions are increasingly used in armed conflicts. An extensive database of loitering munitions is developed based on information available in the public domain. This database includes dimensions, weights, and performance parameters such as flight endurance and communication range. Based upon this dataset, 6 categories of loitering munitions are identified and statistical trends in the form of equations are provided for each category. The statistical trends are supported by aircraft performance theory tailored to loitering munitions applications. Altogether, the combination of the database, statistical trends and aircraft performance theory can be used to analyse the flight performance and design considerations of new loitering munitions of which only limited non-technical information is available in the public domain such as pictures and news articles. Based on the statistical trends and aircraft performance theory it is concluded that for long range applications, the preferred design solution is the conventional configuration. The cruciform configuration is beneficial in case precision flight path control is of prime importance. The tandem wing configuration combines the benefits of a canister launch and relatively high aspect ratio wings suitable for long range flight. Finally, the delta wing design provides a large internal volume and a high terminal attack airspeed. Two example case studies are included to illustrate the flight performance capabilities of two types of loitering munitions used in the current conflict in Yemen (a long range conventional design and a delta wing configuration).

Integrating Unmanned Aircraft Systems into Alaskan Oil Spill Response–Applied Case Studies and Operational Protocols

ABSTRACT> (PS1-02) Unmanned Aircraft Systems (UAS) have a high potential value to support oil spill response activities due to their capabilities to provide real-time situational awareness. A variety of UAS are available to support response activities, and determining the precise aircraft, sensor payload and flight patterns will depend on the operational need for surveillance. In support of UAS integration into America's airspace, the FAA has defined general protocols for the commercial use of small UAS (less than 55 lbs. total take-off weight) in 14 CFR Part 107. However, these regulations do not address any other concerns associated with flight of these small aircraft, such as shared operational airspace within a temporary flight restriction area, or regulations for flight over animals that fall under state or federal management. To address this lack of policy, a UAS protocol for flights of small UAS during oil spill response activities was developed and integrated into a series of tabletop oil spill exercises conducted in Alaska during 2018. The UAS protocol was vetted with state and federal agencies responsible for wildlife management both on and offshore, was modified for execution in remote as well as urban locations, and has been integrated into Area Contingency Plans in Alaska. This presentation will highlight the operational components of the UAS operational protocol, as well as the challenges, both perceived and actual, to UAS integration into the incident management structure of an oil spill response.

Precision Flight Drones with RTK-GNSS

An RTK-GNSS was introduced to realize the precision flight of a drone system for transporting harvested loquats and spraying pesticides to suppress the rotting of fruits. Transportation and spraying experiments were conducted. Precision automatic navigation flights were realized in transportation experiments. In addition, precision landing was performed within approximately 10 cm of the target position. Sufficient spraying flights were performed during the spraying experiment.

The Methods of Helicopter Control in Non-standard Situations

The current system of controlling modern helicopter and supervising its flight is associated with monitoring the effective operation of its systems for control and system integration of specialized on-board systems and complex system of control, too. The control and management structure of helicopter on-board systems is a complex of logically arranged elements that perform alternative functions associated with the stabilization and controllability of the helicopter itself in all flight phases. The functional arrangement of the on-board systems of the next generation of conventional helicopters has a defined task of self-checking with the specified accuracy and with the precise flight task of guiding the helicopter into the area of successful control. In accordance with the principles and architectures used in these intelligent helicopter systems, it is possible to separate different purpose-built subsystems that accept the exact useful properties of a conventional helicopter with its parameters and regarding the overall economy of operation. The influence of the pilot skills and quality of piloting impact the control of the helicopter in non-standard situations, which is the moment, when is there a high probability of failure. The aim of the paper is to define the initial research methods for determining the quality of accurate control of a conventional helicopter which operation is affected by failures.

SECOND ORDER SLIDING MODE CONTROLLER DESIGN WITH OPTIMUM CHARACTERISTIC EQUATION FOR QUADROTORS

Nowadays, small structured micro unmanned aerial vehicles (UAV’s) with four-rotor appears in military and civilian applications. As the usage of these vehicles becomes widespread, the development of controller structures which allow the UAV’s to follow a specified trajectory precisely is a new area of interest for researchers. In this work, nonlinear mathematical model of a four-rotor UAV is obtained. In order to obtain the mathematical model of UAV Newton-Euler equations are used. In the trajectory tracking system of this vehicle, second order sliding mode controller (SOSMC) is designed. Inside of the controller, control process is divided into two subsystems in order to provide position and attitude control. SOSMC is applied to the fully actuated and under actuated subsystems individually. In the next step, coefficients of the SOSMC is determined with optimum characteristic equation. Based on the reference study, boundaries of the predefined characteristic equation is obtained. Later, appropriate values are observed. In final part, simulation results are obtained, and the results are compared with the reference study. As a result, Optimum Characteristic equation results proved its robustness according to the smaller steady state error and more precise flight performance in trajectory. In this study simulation results are obtained using Simulink/MATLAB environment.

Wind disturbance rejection for unmanned aerial vehicles using acceleration feedback enhanced $$H_\infty $$ method

One of the most critical issues for unmanned aerial vehicle (UAV) safety and precision flight is wind disturbance. To this end, this paper presents an acceleration feedback (AF) enhanced $$H_\infty $$ method for UAV flight control against wind disturbance and its application on a hex-rotor platform. The dynamics of the UAV system are decoupled into attitude control and position control loops. A hierarchical $$H_\infty $$ controller is then designed for the decoupled system. Finally, an AF-enhanced method is introduced into the decoupled system without altering the original control structure. The stability of the AF-enhanced $$H_\infty $$ method for the UAV system is analyzed and verified using the $$H_\infty $$ theory. Two types of wind disturbances—continuous and gusty winds—are considered and analyzed for guiding the AF-enhanced controller design. The results of an experimental comparison between the $$H_\infty $$ controller and the AF-enhanced $$H_\infty $$ controller against wind disturbances demonstrate the robustness and effectiveness of the proposed method for wind disturbance rejection.

Simulation of Unmanned Aircraft Vehicle Flight Precision

This paper deals with the Unmanned Aircraft Vehicle (UAV) flight phases dynamics simulation. It predicts the accuracy of the UAV flight using the output graphs. The monitoring of the main flight phases (take-off, en-route, landing) is carried out using instruments, UAV standard procedures and rules established by the applicable aviation standards for the method of Unmanned Aircraft Vehicle operation. The fundamental peculiarity of flight and technical analysis is based on a gradual qualitative change in the movement of a known flying vehicle, where its operating systems and its management and control rules are gradually changed and transformed in accordance with technical, operational and legislative conditions which means the transfer of flight and technical analysis from the area of mathematical-mechanical precise flight tracking and the sophistication of its operation in a mountainous environment.

The Positioning of the Aircraft Using GPS/GLONASS Data

Abstract The article presents the results of aircraft positioning using GPS/GLONASS data in air navigation. In the work, the flight trajectory of the Cessna 172 aircraft was determined on the basis of GPS, GLONASS and GPS/GLONASS data. The coordinates of the Cessna 172 were determined using the least squares method in a stochastic processing compliant with the ICAO recommendations. In the air test, the Cessna 172 made a test flight over EPDE military airfield in Dęblin. The GPS, GLONASS and GPS/GLONASS measurement data from the Topcon HiperPro on-board aircraft installed on the Cessna 172 aircraft were used in the research experiment. The coordinates of the Cessna 172 in the geocentric XYZ and ellipsoidal BLh were compared with the precise flight reference trajectory determined from the differential technique RTK-OTF.