55,522 research outputs found

    Biologically Inspired Feedback Design for Drosophila Flight

    Get PDF
    We use a biologically motivated model of the Drosophila's flight mechanics and sensor processing to design a feedback control scheme to regulate forward flight. The model used for insect flight is the grand unified fly (GUF) [3] simulation consisting of rigid body kinematics, aerodynamic forces and moments, sensory systems, and a 3D environment model. We seek to design a control algorithm that will convert the sensory signals into proper wing beat commands to regulate forward flight. Modulating the wing beat frequency and mean stroke angle produces changes in the flight envelope. The sensory signals consist of estimates of rotational velocity from the haltere organs and translational velocity estimates from visual elementary motion detectors (EMD's) and matched retinal velocity filters. The controller is designed based on a longitudinal model of the flight dynamics. Feedforward commands are generated based on a desired forward velocity. The dynamics are linearized around this operating point and a feedback controller designed to correct deviations from the operating point. The control algorithm is implemented in the GUF simulator and achieves the desired tracking of the forward reference velocities and exhibits biologically realistic responses

    Advanced flight deck/crew station simulator functional requirements

    Get PDF
    This report documents a study of flight deck/crew system research facility requirements for investigating issues involved with developing systems, and procedures for interfacing transport aircraft with air traffic control systems planned for 1985 to 2000. Crew system needs of NASA, the U.S. Air Force, and industry were investigated and reported. A matrix of these is included, as are recommended functional requirements and design criteria for simulation facilities in which to conduct this research. Methods of exploiting the commonality and similarity in facilities are identified, and plans for exploiting this in order to reduce implementation costs and allow efficient transfer of experiments from one facility to another are presented

    4D Continuous Descent Operations Supported by an Electronic Flight Bag

    Get PDF
    This paper describes a set of flight simulation experiments carried out with the DLR’s Generic Cockpit Simulator (GECO). A new concept named time and energy managed operations (TEMO), which aims to enable advanced four dimensional (4D) continuous descent operations (CDO), was evaluated after three full days of experiments with qualified pilots. The experiment focused to investigate the possibility of using a 4D-controller on a modern aircraft with unmodified or only slightly modified avionic systems. This was achieved by executing the controller in an Electronic Flight Bag (EFB) and using the pilot to “close the loop” by entering speed and other advisories into the autopilot Flight Control Unit (FCU). The outcome of the experiments include subjective (questionnaires answered by pilots) and objective (trajectory logs) data. Data analysis showed a very good acceptance (both in terms of safety and operability of the procedure) from the participating crews, only with minor suggestions to be improved in future versions of the controller and the speed advisories update rates. Good time accuracy all along the descent trajectory was also observed.Peer ReviewedPostprint (published version

    Design and evaluation of a LQR controller for the Bluebird Unmanned Air Vehicle

    Get PDF
    The modern aerospace controls engineer is provided with a variety of powerful tools to aid in the design and testing of digital flight control systems. The current fiscal environment requires extensive validation of all aerospace based systems through simulation and hardware-in-the-loop testing prior to implementation. This work explores the design and evaluation of an Automatic Flight Control System (AFCS) for the Bluebird Unmanned Aerial Vehicle (UAV). Software tools such as MATLAB and MATRIXx are used to evaluate the dynamic stability of the aircraft model and Linear Quadratic Gaussian algorithms are used to obtain the appropriate controller. Graphical design applications such as SIMULINK and SystemBuild are then used to build a visual block diagram model of the aircraft dynamics and link it with the designed controller. Using this model, the control system response to commanded inputs and external disturbances was evaluated.http://archive.org/details/designndevaluati1094530934NANAU.S. Navy (U.S.N.) author

    A modular software architecture for UAVs

    Get PDF
    There have been several attempts to create scalable and hardware independent software architectures for Unmanned Aerial Vehicles (UAV). In this work, we propose an onboard architecture for UAVs where hardware abstraction, data storage and communication between modules are efficiently maintained. All processing and software development is done on the UAV while state and mission status of the UAV is monitored from a ground station. The architecture also allows rapid development of mission-specific third party applications on the vehicle with the help of the core module

    Rotorcraft handling-qualities design criteria development

    Get PDF
    Joint NASA/Army efforts at the Ames Research Center to develop rotorcraft handling-qualities design criteria began in earnest in 1975. Notable results were the UH-1H VSTOLAND variable stability helicopter, the VFA-2 camera-and-terrain-board simulator visual system, and the generic helicopter real-time mathematical model, ARMCOP. An initial series of handling-qualities studies was conducted to assess the effects of rotor design parameters, interaxis coupling, and various levels of stability and control augmentation. The ability to conduct in-flight handling-qualities research was enhanced by the development of the NASA/Army CH-47 variable-stability helicopter. Research programs conducted using this vehicle include vertical-response investigations, hover augmentation systems, and the effects of control-force characteristics. The handling-qualities data base was judged to be sufficient to allow an update of the military helicopter handling-qualities specification, MIL-H-8501. These efforts, including not only the in-house experimental work but also contracted research and collaborative programs performed under the auspices of various international agreements. The report concludes by reviewing the topics that are currently most in need of work, and the plans for addressing these topics

    STOL Simulation Requirements for Development of Integrated Flight/propulsion Control Systems

    Get PDF
    The role and use of simulation as a design tool in developing integrated systems where design criteria is largely unavailable is well known. This paper addresses additional simulation needs for the development of Integrated Flight/Propulsion Control Systems (IFPCS) which will improve the probability of properly interpreting simulation results. These needs are based on recent experience with power approach flying qualities evaluations of an advanced fighter configuration which incorporated Short Takeoff and Landing (STOL) technologies and earlier experiences with power approach flying qualities evaluations on the AFTI/F-16 program. The use of motion base platforms with axial and normal degrees of freedom will help in evaluating pilot coupling and workload in the presence of high frequency low amplitude axial accelerations produced by high bandwidth airspeed controllers in a gusty environment

    AirSim: High-Fidelity Visual and Physical Simulation for Autonomous Vehicles

    Full text link
    Developing and testing algorithms for autonomous vehicles in real world is an expensive and time consuming process. Also, in order to utilize recent advances in machine intelligence and deep learning we need to collect a large amount of annotated training data in a variety of conditions and environments. We present a new simulator built on Unreal Engine that offers physically and visually realistic simulations for both of these goals. Our simulator includes a physics engine that can operate at a high frequency for real-time hardware-in-the-loop (HITL) simulations with support for popular protocols (e.g. MavLink). The simulator is designed from the ground up to be extensible to accommodate new types of vehicles, hardware platforms and software protocols. In addition, the modular design enables various components to be easily usable independently in other projects. We demonstrate the simulator by first implementing a quadrotor as an autonomous vehicle and then experimentally comparing the software components with real-world flights.Comment: Accepted for Field and Service Robotics conference 2017 (FSR 2017

    Simulator verification techniques study. Integrated simulator self test system concepts

    Get PDF
    Software and hardware requirements for implementing hardware self tests are presented in support of the development of training and procedures development simulators for the space shuttle program. Self test techniques for simulation hardware and the validation of simulation performance are stipulated. The requirements of an integrated simulator self system are analyzed. Readiness tests, fault isolation tests, and incipient fault detection tests are covered
    corecore