scholarly journals Parachute-Payload System Flight Dynamics and Trajectory Simulation

2012 ◽  
Vol 2012 ◽  
pp. 1-17 ◽  
Author(s):  
Giorgio Guglieri
Keyword(s):  
General Procedure ◽  
Simulation Models ◽  
Flight Simulation ◽  
Mission Design ◽  
Coupling Mechanism ◽  
Simulation Tool ◽  
Multibody Model ◽  
Deceleration Phase ◽  
Area Of Interest ◽  
Implementation Guidelines

The work traces a general procedure for the design of a flight simulation tool still representative of the major flight physics of a parachute-payload system along decelerated trajectories. An example of limited complexity simulation models for a payload decelerated by one or more parachutes is given, including details and implementation features usually omitted as the focus of the research in this field is typically on the investigation of mission design issues, rather than addressing general implementation guidelines for the development of a reconfigurable simulation tool. The dynamics of the system are modeled through a simple multibody model that represents the expected behavior of an entry vehicle during the terminal deceleration phase. The simulators are designed according to a comprehensive vision that enforces the simplification of the coupling mechanism between the payload and the parachute, with an adequate level of physical insight still available. The results presented for a realistic case study define the sensitivity of the simulation outputs to the functional complexity of the mathematical model. Far from being an absolute address for the software designer, this paper tries to contribute to the area of interest with some technical considerations and clarifications.

Rotorcraft Lateral-Directional Oscillations: The Anatomy of a Nuisance Mode

2021 ◽  
Author(s):  
Dheeraj Agarwal ◽  
Linghai Lu ◽  
Gareth D. Padfield ◽  
Mark D. White ◽  
Neil Cameron
Keyword(s):  
Simulation Model ◽  
Simulation Models ◽  
Flight Test ◽  
Flight Simulation ◽  
Stability And Control ◽  
Systems Research ◽  
Control Derivatives ◽  
Research Aircraft ◽  
Level Of Understanding ◽  
And Control

High-fidelity rotorcraft flight simulation relies on the availability of a quality flight model that further demands a good level of understanding of the complexities arising from aerodynamic couplings and interference effects. One such example is the difficulty in the prediction of the characteristics of the rotorcraft lateral-directional oscillation (LDO) mode in simulation. Achieving an acceptable level of the damping of this mode is a design challenge requiring simulation models with sufficient fidelity that reveal sources of destabilizing effects. This paper is focused on using System Identification to highlight such fidelity issues using Liverpool's FLIGHTLAB Bell 412 simulation model and in-flight LDO measurements from the bare airframe National Research Council's (Canada) Advanced Systems Research Aircraft. The simulation model was renovated to improve the fidelity of the model. The results show a close match between the identified models and flight test for the LDO mode frequency and damping. Comparison of identified stability and control derivatives with those predicted by the simulation model highlight areas of good and poor fidelity.

scholarly journals Simulation Modeling of the Sustainable Supply Chain

2020 ◽  
Vol 12 (15) ◽  
pp. 6007 ◽  
Author(s):  
Patrycja Hoffa-Dabrowska ◽  
Katarzyna Grzybowska
Keyword(s):  
Sustainable Development ◽  
Supply Chain ◽  
Global Economy ◽  
Simulation Models ◽  
Exhaust Emissions ◽  
Simulation Tool ◽  
Sustainable Supply Chain ◽  
Use Of Resources ◽  
Negative Impacts ◽  
The Impact

The development of the global economy affects the environment in which we are living, often in negative ways, including pollutions, exhaust emissions, depletion of natural resources, and other concerns. Therefore, it is so important to use resources in a reasonable, sustainable manner and to be aware of the impact of our activities on the environment, which in the next stage translates into trying to limit negative impacts to the environment. Aspects of sustainable supply chain (SSC) have become more and more popular in the last years. Entrepreneurs pay more attention to the aspect of sustainable development in their activities, especially to exhaust emissions. The rational use of resources is also a very important topic. Not only economic aspects but also environmental and social topics are taken into account in company politics, which is characteristic of sustainable development. The main purpose of this article is to show the benefits of SSC. For this purpose, the simulation models showing the supply chain and the sustainable supply chain will be built. The benefits of SSC in economic and environmental aspects will be presented using a computer simulation tool. Using a simulation tool fits in with sustainability; thanks to modeling supply chains in their virtuality and analysis, many resources can be saved in reality (for example, thanks to the consolidation of freight).

scholarly journals The COVID-19 pandemic preparedness simulation tool: CovidSIM

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Kristan A. Schneider ◽  
Gideon A. Ngwa ◽  
Markus Schwehm ◽  
Linda Eichner ◽  
Martin Eichner
Keyword(s):  
Decision Support ◽  
Simulation Models ◽  
Simulation Tool ◽  
Web Interface ◽  
Pandemic Preparedness ◽  
Seasonal Fluctuations ◽  
Seir Model ◽  
Peak Number ◽  
Efficient Control ◽  
Control And Management

Abstract Background Efficient control and management in the ongoing COVID-19 pandemic needs to carefully balance economical and realizable interventions. Simulation models can play a cardinal role in forecasting possible scenarios to sustain decision support. Methods We present a sophisticated extension of a classical SEIR model. The simulation tool CovidSIM Version 1.0 is an openly accessible web interface to interactively conduct simulations of this model. The simulation tool is used to assess the effects of various interventions, assuming parameters that reflect the situation in Austria as an example. Results Strict contact reduction including isolation of infected persons in quarantine wards and at home can substantially delay the peak of the epidemic. Home isolation of infected individuals effectively reduces the height of the peak. Contact reduction by social distancing, e.g., by curfews, sanitary behavior, etc. are also effective in delaying the epidemic peak. Conclusions Contact-reducing mechanisms are efficient to delay the peak of the epidemic. They might also be effective in decreasing the peak number of infections depending on seasonal fluctuations in the transmissibility of the disease.

Multibody Modeling and Simulation of Monocopter Micro Air Vehicle

2015 ◽  
Vol 772 ◽  
pp. 401-409
Author(s):  
Mehrdad Ebrahimi Dormiyani ◽  
Afshin Banazadeh ◽  
Fariborz Saghafi
Keyword(s):  
Degrees Of Freedom ◽  
Initial Conditions ◽  
Model Simulation ◽  
Static Stability ◽  
Flight Simulation ◽  
Control Surface ◽  
Free Flight ◽  
Nonlinear Simulation ◽  
Multibody Model ◽  
Air Vehicle

In the current paper, seven degrees of freedom multibody model of a monocopter air vehicle is developed based on the Newton-Euler approach along with nonlinear simulation in different flight phases. Aerodynamic forces and moments are modeled using blade element momentum theory. The sole control surface is modeled like a conventional flap on a wing. Free flight simulation is performed in MATLAB Simulink environment to evaluate the behavior of the system and to demonstrate the effectiveness and applicability of the proposed model. Simulation results show harmonic oscillations in Euler angles, linear and angular velocities that are consistent with the physics and mathematical foundations. Static stability of the vehicle is evident in free flight by careful choice of initial conditions. The presented multibody model is useful for comparative study and design purposes.

Simulation of Cloud Platform Supporting Wireless Sensor Network

2020 ◽  
Vol 17 (6) ◽  
pp. 2613-2620
Author(s):  
Shweta Sharma ◽  
Amandeep Kaur
Keyword(s):  
Neural Network ◽  
Cloud Computing ◽  
Power Management ◽  
Wireless Sensor ◽  
Simulation Tool ◽  
Management Issue ◽  
Cloud Platform ◽  
Area Of Interest ◽  
Military Applications ◽  
Artificial Neural Network Ann

WSN has been an area of interest for a lot of researchers as well as the industry specialist due to its high usage in healthcare, military applications and in robotics. The focus area of WSN has been energy consumption. Integration of Cloud Computing in WSN has been observed by couple of research scholars as Cloud has been observed to be struggling against the power management issue. This paper presents a novel solution of power management in Cloud computing which uses the concept of clustering borrowed from WSN. The jobs are grouped or Clustered as per the algorithmic architecture of WSN and the minimization of migration is attempted using Genetic Algorithm (GA). Artificial Neural Network (ANN) is used as a conjunction to GA for energy efficiency. MATLAB is used as a simulation tool and consumed energy has been evaluated as the major evaluation parameter.

scholarly journals Modelling of Classical and Rotary Inverted Pendulum Systems – A Generalized Approach

2013 ◽  
Vol 64 (1) ◽  
pp. 12-19 ◽  
Author(s):  
Slávka Jadlovský ◽  
Ján Sarnovský
Keyword(s):  
Program Implementation ◽  
Inverted Pendulum ◽  
General Procedure ◽  
Simulation Models ◽  
Open Loop ◽  
Dissipation Function ◽  
Lagrange Equations ◽  
Pendulum System ◽  
Inverted Pendulum System ◽  
Rotary Inverted Pendulum

The purpose of this paper is to present the design and program implementation of a general procedure which yields the mathematical model for a classical or rotary inverted pendulum system with an arbitrary number of pendulum links. Lagrange equations of the second kind with an integrated Rayleigh dissipation function are employed in model design, and the energetic balance relations, derived for the base and all pendulum links in a generalized (n-link) classical and rotary inverted pendulum system, are implemented in form of symbolic MATLAB functions and a MATLAB GUI application. The validity and accuracy of motion equations generated by the application are demonstrated by evaluating the open-loop responses of simulation models of classical double and rotary single inverted pendulum.

Study on flight safety manipulation space under complex conditions

2018 ◽  
Vol 233 (2) ◽  
pp. 725-735 ◽  
Author(s):  
Zhe Li ◽  
Haojun Xu ◽  
Yuan Xue ◽  
Binbin Pei
Keyword(s):  
Situational Awareness ◽  
Complex Dynamics ◽  
Three Dimensional ◽  
Simulation Models ◽  
Flight Simulation ◽  
Flight Safety ◽  
Flight Data ◽  
Dimensional Distribution ◽  
Aircraft Performance ◽  
Engine Failure

This study considers the situational awareness under complex conditions like aircraft failures or adverse environments. To enhance pilot’s situational awareness, flight safety manipulation space is proposed based on risk prediction. Current methods normally predict the occurrence of accidents by estimating whether the safety-related parameters exceed their limitations. The complex dynamics of pilot–vehicle–environment simulation models are built and the safety-related flight data are represented by risk colors according to their limits. The safety spectrum is then obtained by the integration of the flight data under a certain manipulation action, and the colored risk value for the single flight condition is further acquired. The colored two-dimensional and three-dimensional distribution topology maps can be calculated by a parallel flight simulation platform. The flight safety manipulation space for one-side engine failure and main surface jams are researched and the disaster-causing mechanism is analyzed. Simulation results show that the outbreak failure may lead to the shrink and even distortion of the safety manipulation space. The proposed method could provide a theoretical support for pilots to enhance situational awareness under complex adverse conditions, an engineering tool for aircraft designers to optimize the aircraft performance, and a visualization analysis method to reveal the accident evolution.

scholarly journals A general on-the-fly algorithm for modifying the kinematic tree hierarchy

2012 ◽  
Vol 22 (2) ◽  
pp. 423-435
Author(s):  
Jakub Stępień ◽  
Andrzej Polański ◽  
Konrad Wojciechowski
Keyword(s):  
Mechanical System ◽  
Dynamic Simulation ◽  
General Procedure ◽  
Simulation Models ◽  
Time Varying ◽  
Simulation Procedure ◽  
Articulated Figures ◽  
Current State ◽  
External Objects ◽  
The Way

A general on-the-fly algorithm for modifying the kinematic tree hierarchyWhen conducting a dynamic simulation of a multibody mechanical system, the model definition may need to be altered during the simulation course due to, e.g., changes in the way the system interacts with external objects. In this paper, we propose a general procedure for modifying simulation models of articulated figures, particularly useful when dealing with systems in time-varying contact with the environment. The proposed algorithm adjusts model connectivity, geometry and current state, producing its equivalent ready to be used by the simulation procedure. Furthermore, we also provide a simple usage scenario—a passive planar biped walker.

scholarly journals The impact of radio-tags on Ruby-throated Hummingbirds (Archilochus colubris)

2014 ◽  
Author(s):  
Theodore J Zenzal ◽  
Robert H Diehl ◽  
Frank R Moore
Keyword(s):  
Radio Telemetry ◽  
Bird Species ◽  
Simulation Models ◽  
Flight Time ◽  
Flight Simulation ◽  
Additional Information ◽  
Flight Range ◽  
Significant Difference ◽  
Radio Tagging ◽  
The Impact

Radio telemetry has advanced the field of wildlife biology, especially with the miniaturization of radio-tags. However, the major limitation faced with radio-tagging birds is the size of the animal to which a radio-tag can be attached. We tested how miniature radio-tags affected flight performance and behavior of Ruby-throated Hummingbirds (Archilochus colubris), possibly the smallest bird species to be fitted with radio-tags. Using eyelash adhesive, we fitted hatch year individuals (n=20 males and 15 females) with faux radio-tags of three sizes varying in mass and antenna length (220mg-12.7cm, 240mg-12.7cm, and 220mg-6.35cm), then filmed the birds in a field aviary to quantify activity budgets. We also estimated flight range using flight simulation models. When the three radio-tag packages were pooled for analysis, the presence of a radio-tag significantly decreased both flight time (-8%) and modeled flight range (-23%) when compared to control birds. However, a multiple comparison analysis between the different packages revealed that there was a significant difference in flight time when the larger radio-tag package (240mg) was attached and no significant difference in flight time when the lighter radio-tag packages (220mg) were attached. Our results are similar to other studies which analyzed the flight time or flight range of birds wearing radio-tags. Therefore, currently available light weight radio-tags (≤220mg) may be a new option to aid in the study of hummingbird biology. Future study should focus upon the additional drag created by the radio-tag and the effects of the lightest radio-tag packages on free ranging birds. These studies would provide additional information to determine the feasibility on the use of radio-tags to study hummingbird biology. Keywords: radio transmitters, radio telemetry, Ruby-throated Hummingbirds, Archilochus colubris, radio-tagging, behavior, flight simulations, migration

Development of a Simulation Tool for Gas Co-Generation Systems

1999 ◽  
Author(s):  
Yukimaro Murata ◽  
Tomohiko Horizoe ◽  
Masahiro Oka
Keyword(s):  
Energy Consumption ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Simulation Models ◽  
Gas Absorption ◽  
Simulation Tool ◽  
Simulation Tools ◽  
Absorption Chillers ◽  
Running Cost

Abstract Tokyo Gas developed a new simulation tool for gas co-generation systems. We expect that this tool will help us in both developing co-generation components such as absorption chillers to utilize the waste heat of co-generation and making suggestion for optimum co-generation engineering. This simulation tool is superior to other simulation tools in simulation result accuracy and availability to complicated co-generation systems. It was achieved by new calculation logic and detailed description of features of co-generation components. This simulation tool can evaluate energy consumption and running cost of simulation models for buildings with co-generation systems. Tokyo Gas has used this simulation tool in development of three new gas absorption chiller heaters with auxiliary waste heat recovery and for energy consumption evaluation of many buildings with co-generation systems, which are so complicated that other simulation tools are not available.

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