Flight Algorithm Research Articles

An Improved Marriage in Honey Bees Optimization Algorithm for Single Objective Unconstrained Optimization

Marriage in honey bees optimization (MBO) is a metaheuristic optimization algorithm developed by inspiration of the mating and fertilization process of honey bees and is a kind of swarm intelligence optimizations. In this study we propose improved marriage in honey bees optimization (IMBO) by adding Levy flight algorithm for queen mating flight and neighboring for worker drone improving. The IMBO algorithm's performance and its success are tested on the well-known six unconstrained test functions and compared with other metaheuristic optimization algorithms.

Swarm Intelligence and Its Applications

Swarm Intelligence and Its Applications

Cluster Flight Algorithms for Disaggregated Satellites

In disaggregated satellites, the functional capabilities of a single monolithic satellite are distributed among multiple free-flying, wirelessly communicating modules. One of the main challenges associated with disaggregated satellites is cluster flight, i.e., keeping the modules within a bounded distance, typically less than 100 km, for the entire mission lifetime. This paper presents a methodological development of cluster flight algorithms for disaggregated satellite systems in low Earth orbits. To obtain distance-bounded relative motion a new constraint on the initial conditions of the modules is developed. A concomitant analytical bound on the relative distance between the modules is proven based on a design model assuming time invariance of the environmental perturbations. It is then shown that if the actual astrodynamical model includes other possible time-varying effects, mild drifts between the modules are obtained. Furthermore, this paper presents a detailed impulsive cluster establishment and cluster-keeping algorithm for tracking a given nominal orbit, whose characteristics satisfy the previously developed no-drift constraint. This algorithm provides fuel balancing among the maneuvering modules, as well as the minimization of the total fuel consumption, while guaranteeing a collision-free operation. Numerical simulations using representative astrodynamical models are used to validate the analysis.

Research on the Algorithm of Aviation Emergency Rescue under Major Disasters

The reason of inefficient of current aviation emergency rescue was analyzed in this paper, and the establishment of a three layers of emergency rescue system with the background of civil aviation management system was proposed, under which the aircraft allocation algorithm between rescue center and disaster was studied, and also the course design algorithm and aircraft flight algorithm. These algorithms can improve the efficiency and safety of aviation rescue greatly, which laid a significant basis for the establishment of the emergency rescue plans under major disasters.

TALARIS project update: Overview of flight testing and development of a prototype planetary surface exploration hopper

The TALARIS (Terrestrial Artificial Lunar And Reduced GravIty Simulator) project is intended to test GNC (Guidance, Navigation, and Control) algorithms on a prototype planetary surface exploration hopper in a dynamic environment with simulated reduced gravity. The vehicle is being developed by the Charles Stark Draper Laboratory and Massachusetts Institute of Technology in support of efforts in the Google Lunar X-Prize contest. This paper presents progress achieved since September 2010 in vehicle development and flight testing.Upgrades to the vehicle are described, including a redesign of the power train for the gravity-offset propulsion system and a redesign of key elements of the spacecraft emulator propulsion system. The integration of flight algorithms into modular flight software is also discussed.Results are reported for restricted degree of freedom (DOF) tests used to tune GNC algorithms on the path to a full 6-DOF hover-hop flight profile. These tests include 3-DOF tests on flat surfaces restricted to horizontal motion, and 2-DOF vertical tests restricted to vertical motion and 1-DOF attitude control. The results of tests leading up to full flight operations are described, as are lessons learned and future test plans.

자유비행 다중 충돌회피 효율성 측정 연구

본 논문에서는 자율형 운항 알고리즘을 활용하여 분리보증 해결과 충돌탐지거리와의 상관관계, 충돌회피 후 경로점 복귀와 시간제약 조건에 따른 항로 복귀, 3대 이상의 다중 충돌회피 상황의 분리보증 실험을 수행하여 운항환경에서 발생하는 실증적인 문제를 규명하였다. 실험결과 자유비행 충돌회피를 위하여 탐지거리 확대가 분리보증 해결과 운항 효율성 향상에 유리하며, 충돌회피 후 복귀기동 시 충돌예측상황에 따라 고정 경로점 복귀 또는 시간제약 조건을 적용한 항로 복귀기동을 선택할 수 있었다. 그리고 다중 충돌 상황에서 2도 이상의 선회각을 적용하면 분리보증 해결되었고, 최적의 선회각 선택 시에는 운항 효율성을 대폭 향상시킬 수 있었다. In this paper, study the substantial issues which occurs upon free flight environment by performing separation assurance under multiple conflict(over 3 Aircraft), recovery en route under the terms of time constrains and fixed way point after the conflict avoidance, correlations between conflict detection distance and separation assurance by utilizing Autonomous flight algorithm. Result of this experiment demonstrates that the extension of detection distance is advantageous to solution of separation assurance and enhancing of flight efficiency, choose to maneuver by applying time constrain terms and fixed way point according to the situation of conflict prediction in case of recovery maneuver after the conflict avoidance. And separation assurance can be solved by applying 2 degrees or more of bank angle. When choosing the optimal bank angle could be drastically improved flight efficiency.

자율형 운항 알고리즘 설계 연구

Airborne separation assurance is a key requirement for Free Flight. This paper is to propose autonomous flight algorithm, such as extended authority of delegation, efficiency of airspace issue to deal with the empirical solution for free flight, and to measure flight efficiency and conflict detection and resolution (CD&R) by utilizing flight performance data under the two circumstances of scenario with the modeling of proposed algorithm and potential field algorithm. The results show that the autonomous flight algorithm is superior to the potential field algorithm under the circumstances of free flight airspace in terms of algorithm performance, CD&R, and flight efficiency.

Evolution of the Space Shuttle Primary Avionics Software and Avionics for Shuttle Derived Launch Vehicles

As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA s Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a long pole in new development efforts. The and for the Space Shuttle was primarily developed in the 70 s and considered state of the art for that time. As one may argue that the existing and flight may be too outdated to the new SDLV effort, this is a fallacy if they can be evolved over time into a avionics platform. The technology may be outdated, but the concepts and flight algorithms are not. The reuse of existing and also allows for the reuse of development, verification, and operations facilities. The keyword is evolve in that these assets can the fast development of such a vehicle, but then be gradually evolved over time towards more modern platforms as budget and schedule permits. The gold of the flight is the control loop algorithms of the vehicle. This is the Guidance, Navigation, and Control (GNC) algorithms. This is typically the most expensive to develop, test, and verify. Thus, the approach is to preserve the flight software, while first evolving the supporting (such as Command and Data Handling, Caution and Warning, Telemetry, etc.). This can be accomplished by gradually removing the support software from the legacy flight leaving only the algorithms. The support software could be re-developed for modern platforms, while leaving the algorithms to execute on technology compatible with the legacy system. It is also possible to package the algorithms into an emulated version of the original computer (via Field Programmable Gate Arrays or FPGAs), thus becoming a GNC on a Chip solution where it could live forever to be embedded in modern platforms.

편대 유도 법칙 및 초소형 비행체의 자동 편대 비행 구현

본 논문에서는 초소형 비행체의 자동 편대 비행을 위한 유도 법칙과 비행 시험 결과를 기술하였다. 초소형 비행체는 탑재 중량과 비행시간 등의 제한으로 인해 짧은 시간 안에 복수의 비행체가 임무를 분담하거나 협력하여 동시에 수행하는 것이 효율적이며 편대 비행은 이러한 임무 하중을 효과적으로 감소시킬 수 있다. 제안된 편대 유도 법칙은 Leader-Follower 편대 비행의 기하학적 관계 기반으로 비선형 모델 역변환 기법을 이용하여 설계하였다. 편대 유도 법칙에 필요한 비행체의 상태 정보는 비행체 간 고속의 데이터 통신 시스템을 구성하고 지상국을 통해 송수신하도록 하였다. 본 연구에서 제안된 비행체간 통신 기반의 편대 유도 기법은 센서의 측정 잡음에 대한 강건한 성능을 확인하기 위해 실제 비행 데이터 기반 시뮬레이션을 수행하였고 다수의 초소형 비행체를 이용한 편대 비행 시험을 통해 유도 법칙의 타당성을 검증하고 확인하였다. This paper presents an autonomous formation flight algorithm for micro aerial vehicles (MAVs) and its flight test results. Since MAVs have severe limits on the payload and flight time, formation of MAVs can help alleviate the mission load of each MAV by sharing the tasks or coverage areas. The proposed formation guidance law is designed using nonlinear dynamic inversion method based on 'Leader-Follower' formation geometric relationship. The sensing of other vehicles in a formation is achieved by sharing the vehicles' states using a high-speed radio data link. the designed formation law was simulated with flight data of MAV to verify its robustness against sensor noises. A series of test flights were performed to validate the proposed formation guidance law. The test result shows that the proposed formation flight algorithm with inter-communication is feasible and yields satisfactory results.

Autonomous Formation Flight Test of Multi-Micro Aerial Vehicles

This paper presents an autonomous formation flight algorithm for micro aerial vehicles (MAVs) and its experiment results. We choose the leader---follower scheme for formation flight as it is more appropriate for tracking arbitrary maneuvering of the leader in a formation. The sensing of other vehicles in the formation is achieved by sharing the vehicles' states using a high-speed peer-to-peer radio data link. The designed guidance law is combined with a PD controller for tracking heading, velocity and altitude commands. A series of test flights were performed to validate the proposed formation guidance law. The test result confirms that the proposed formation flight algorithm is feasible to yield satisfactory results.

Viscoelastic and Anisotropic Mechanical Properties of in vivo Muscle Tissue Assessed by Supersonic Shear Imaging

The in vivo assessment of the biomechanical properties of the skeletal muscle is a complex issue because the muscle is an anisotropic, viscoelastic and dynamic medium. In this article, these mechanical properties are characterized for the brachialis muscle in vivo using a noninvasive ultrasound-based technique. This supersonic shear imaging technique combines an ultra-fast ultrasonic system and the remote generation of transient mechanical forces into tissue via the radiation force of focused ultrasonic beams. Such an ultrasonic radiation force is induced deep within the muscle by a conventional ultrasonic probe and the resulting shear waves are then imaged with the same probe (5 MHz) at an ultra-fast framerate (up to 5000 frames/s). Local tissue velocity maps are obtained with a conventional speckle tracking technique and provide a full movie of the shear wave propagation through the entire muscle. Shear wave group velocities are then estimated using a time of flight algorithm. This approach provides a complete set of quantitative and in vivo parameters describing the muscle’s mechanical properties as a function of active voluntary contraction as well as passive extension of healthy volunteers. Anisotropic properties are also estimated by tilting the probe head with respects to the main muscular fibers direction. Finally, the dispersion of the shear waves is studied for these different configurations and shear modulus and shear viscosity are quantitatively assessed assuming the viscoelastic Voigt’s model. (E-mail: jl.gennisson@espci.fr)

Relative Angles-Only Navigation and Pose Estimation For Autonomous Orbital Rendezvous

This paper explores the potential of using angles-only navigation to perform various autonomous orbital rendezvous and close proximity operations. A 32-state extended Kalman filter is developed that processes angular measurements from an optical navigation camera along with gyro and star tracker data to estimate the inertial position, velocity, attitude, and angular rates of both a target and chaser vehicle. The target satellite is assumed to be passive while the chaser may perform a variety of autonomous rendezvous and close proximity maneuvers. The navigation filter’s performance is evaluated and tested by running a coded prototype in a closed loop 6 degree-of-freedom simulation tool containing the various sensors, actuators, GN&C flight algorithms, and dynamics associated with a simple rendezvous scenario. The analysis performed for this study uses standard Monte-Carlo techniques. These results not only include the navigation errors associated with implementing an angles-only navigation scheme, but they also reveal the dispersions from the nominal trajectory associated with this particular technique in a closed-loop GN&C setting. The rendezvous scenario duplicates a similar close proximity scenario analyzed using linear covariance analysis. Both methods are compared to add validity to the results and highlight the advantages and potential of each approach for autonomous orbital rendezvous and close proximity operation analysis.

Brownian Dynamics Simulation of the Capture of Primary Radicals in Dispersions of Colloidal Polymer Particles

The kinetics of collision between primary persulfate radicals and colloidal polymer particles, a key issue in emulsion polymerization modeling, is determined by the simulation of Brownian dynamics using a Monte Carlo random flight algorithm. The results obtained confirm the ideal behavior predicted by Smoluchowski's kinetic equation only in colloidal dispersions of very low polymer volume fractions (<0.1%), while at higher values, significant deviations from ideality are observed. This deviation from ideality, designated as the Smoluchowski number (Sm), is found to increase almost linearly with the volume fraction of the dispersion. The kinetic model considering the effect of volume fraction is compared with previous experimental data. A satisfactory explanation for the different functional dependences of the radical entry rate on particle diameter is obtained. It is concluded that the polymer volume fraction in the dispersion plays a major role in the mechanism of radical capture by polymer particles.

틸트로터 항공기의 경로점 추종 비행유도제어 알고리즘 설계 : 헬리콥터 비행모드

This paper deals with an autonomous flight guidance and control algorithm design for TR301 tilt-rotor airplane under development by Korea Aerospace Research Institute for simulation purpose. The objective of this study is to design autonomous flight algorithm in which the tilt-rotor airplane should follow the given waypoints precisely. The approach to this objective in this study is that, first of all, model-based inversion is applied to the highly nonlinear tilt-rotor dynamics, where the tilt-rotor airplane is assumed to fly at helicopter flight mode(nacelle angle

Computer-Aided Flight Simulators: A Design Concept

This paper is concerned with the concept and principles of designing computer-aided flight simulators, algorithms and programs for modeling aircraft dynamics and kinematics based on unit vectors and integration of the state matrix in an orthonormal connected coordinate system and airplane coordinates in a normal coordinate system. Singular points are easily determined. A method is designed for forming learning information on control actions by an electronic instructor as graphs, voiced messages, and sound effects. Algorithms for designing control circuits and generating flight instruction texts, dubbing them, and help are elaborated. Principles of information exchange a local area network of the simulator through a logical ring are formulated. The simulator can be adapted to any aircraft modification.

Neural-fuzzy scheduling of H robust controllers for a high performance fighter aircraft under a Herbst-like manoeuvre

This paper presents a flight control system design method witha neural-fuzzy gain-scheduling algorithm with learning capability for a high performance fighter aircraft undergoing a high angle of attack velocity vector roll manoeuvre. This manoeuvre is similar to the Herbst manoeuvre, hence also called a Herbst-like manoeuvre. Two linear H robust controllers are designed by using the mu -synthesis method at two trim conditions that cover the whole dynamic range of this manoeuvre. Then a scheduling technique is proposed, using the neural-fuzzy concept, together witha dynamic back propagation algorithm for its training. Simulation results, using a recently developed non-linear six-degree-of-freedom aircraft simulation package, demonstrate that the neural-fuzzy scheduler can be trained by using the dynamic back propagation algorithm to achieve better closed-loop tracking performance, and the proposed neural-fuzzy scheduled flight control system gives satisfactory performance inexecuting this Herbst-like manoeuvre.

Method for Designing Airport Terminal Concepts

Much design effort in airport planning is expended on terminal concept development. Such a method has been developed and is introduced. It considers the terminal as a system of basic facilities that house the activities and links that represent the passenger traffic flow lines. The method uses heuristic programming to achieve an optimum design. The method is composed of three interacting algorithms: (1) the facility sizing algorithm; (2) the flight assignment algorithm; and (3) the facility layout algorithm. The output consists of a strategy for flight assignment, a layout showing the configuration of gate positions at the apron level, and a plan of terminal elements at three different building levels. The output is preliminary and should be taken as a benchmark for further concept development and design. Several hypothetical design problems were tested successfully. /ASCE/