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Eaton, NY, United States

Dunaevsky V.,Advanced Engineering
American Society of Mechanical Engineers, Tribology Division, TRIB | Year: 2011

A method of a microscopic wear estimation which does not require measurement of the original surface texture and that was developed by the author for Gaussian surfaces is extended here to the non-Gaussian two-process surfaces. © 2011 by ASME. Source

Fraire U.,Jacobs Engineering | Anderson K.,Advanced Engineering | Varela J.G.,GeoControl Systems Inc. | Bernatovich M.A.,NASA
Aerodynamic Decelerator Systems Technology Conferences | Year: 2015

NASA’s Orion Capsule Parachute Assembly System (CPAS) project has advanced into the third generation of its parachute test campaign and requires technically comprehensive modeling capabilities to simulate multi-body dynamics (MBD) of test articles released from a C-17. Safely extracting a 30,000 lbm mated test article from a C-17 and performing stable mid-air separation maneuvers requires an understanding of the interaction between elements in the test configuration and how they are influenced by extraction parachute performance, aircraft dynamics, aerodynamics, separation dynamics, and kinetic energy experienced by the system. During the real-time extraction and deployment sequences, these influences can be highly unsteady and difficult to bound. An avionics logic window based on time, pitch, and pitch rate is used to account for these effects and target a favorable separation state in real time. The Automatic Dynamic Analysis of Mechanical Systems (ADAMS) simulation has been employed to fine-tune this window, as well as predict and reconstruct the coupled dynamics of the Parachute Test Vehicle (PTV) and Cradle Platform Separation System (CPSS) from aircraft extraction through the mid-air separation event. The test-technique for the extraction of CPAS test articles has evolved with increased complexity and requires new modeling concepts to ensure the test article is delivered to a stable test condition for the programmer phase. Prompted by unexpected dynamics and hardware malfunctions in drop tests, these modeling improvements provide a more accurate loads prediction by incorporating a spring-damper line-model derived from the material properties. The qualification phase of CPAS testing is on the horizon and modeling increasingly complex test-techniques with ADAMS is vital to successfully qualify the Orion parachute system for human spaceflight. © 2015, AIAA American Institute of Aeronautics and Astronautics. All rights reserved. Source

Kamalakannan K.,Hindustan University | ElayaPerumal A.,Anna University | Mangalaramanan S.,Advanced Engineering | Arunachalam K.,Anna University
Jordan Journal of Mechanical and Industrial Engineering | Year: 2011

Semi-active suspension uses a special adaptive damper whose damping properties vary with road conditions under the influence of an electromagnet. The adaptive damper is used along with a sophisticated electronic circuit which constantly monitors the changing road conditions and adapts accordingly. The aim of this paper is to simulate and analyze a simple and low-cost semi active suspension system using 'MATLAB and SIMULINK' platform and establish its superiority, and also involves the development and simulation of a virtual quarter car model. Thereafter the graphical results obtained are analyzed. The model is developed using equations of motion involving stiffness, damping ratio and displacement. These equations are translated into a simple data flow circuit in the simulation software to obtain definite results in the form of graphical output. This paper aims at the development of a simpler and cheaper semi active suspension system which will allow its fitment in comparatively affordable cars. © 2011 Jordan Journal of Mechanical and Industrial Engineering. Source

Mariappan V.,Indian Institute of Technology Madras | Srinivas S.,Indian Institute of Technology Madras | Narayanan V.,Advanced Engineering
2014 International Conference on Optimization of Electrical and Electronic Equipment, OPTIM 2014 | Year: 2014

Two new brake energy recovery schemes employing ultracapacitor (UCAP) and a unidirectional power converter are proposed in this paper for recovery of brake energy in the conventional gasoline vehicle. Control algorithms are proposed for the same to direct brake energy (during braking operation) in to UCAP and subsequently from the UCAP to the vehicle loads and battery. The use of stored energy in UCAP relives the alternator torque on the engine, resulting in reduced fuel consumption thereby facilitates improvement in the fuel economy in the vehicle. Both the proposed schemes can be retrofitted as simple add-ons to the existing conventional vehicle thus obviating the need of any modifications to it. The proposed schemes are simulated first using MATLAB and experimentally verified. New European drive cycle (NEDC) is used in this work in order to understand the fuel economy benefits. It is found that the rear axle alternator mounted scheme yields almost thrice times fuel economy benefits compared to the engine mounted alternator scheme. © 2014 IEEE. Source

Mair A.,Advanced Engineering | Thurner T.,University of Graz
CIMSA 2010 - IEEE International Conference on Computational Intelligence for Measurement Systems and Applications, Proceedings | Year: 2010

This paper describes a method for monitoring the condition of reciprocating aircraft engines. In contrast to existing solutions our method is based on information from a single acceleration sensor attached onto the motor block. Model based signal processing using modal analysis and fuzzy logic in a hierarchical estimation scheme enables the possibility to observe engine health level. For each cylinder of the reciprocating system misfire detection and the identification of combustion failures on a per cylinder basis is possible. © 2010 IEEE. Source

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