A Survey of Rail Vehicle Testing for Validation of Theoretical Dynamic Analyses

1978 ◽  
Vol 100 (4) ◽  
pp. 238-251 ◽  
Author(s):  
N. K. Cooperrider ◽  
E. H. Law
Keyword(s):  
Field Testing ◽  
Forced Response ◽  
Rock And Roll ◽  
Rail Vehicle ◽  
Dynamic Analyses ◽  
Freight Car ◽  
Roller Rig ◽  
Validation Tests ◽  
Vehicle Testing ◽  
Validation Testing

This paper discusses experience in rail vehicle testing for validation of theoretical rail vehicle dynamic analyses. Laboratory and field testing are covered including shaker, roller rig, freight car rock and roll, vehicle stability, vehicle forced response, and rail vehicle curving tests. The specific vehicle and roadbed characterization requirements for validation tests are described. Some of the shortcomings of previous testing efforts are outlined and recommendations for future validation testing made.

Development of a Driving Simulator for Virtual Evaluation of Vehicle Dynamics

2010 ◽  
Author(s):  
A. M. Sharaf
Keyword(s):  
Performance Evaluation ◽  
Vehicle Dynamics ◽  
Driving Simulator ◽  
Field Testing ◽  
Vehicle Performance ◽  
Vehicle Simulation ◽  
Virtual Platform ◽  
The Cost ◽  
Vehicle Testing ◽  
Simulation Package

This paper delineates the conceptual algorithms of a driving simulator which is intended for vehicle performance evaluation and to act as a virtual platform for research studies and therefore eliminates the cost and dangerous of field testing. A virtual proving ground for vehicle testing has been devised through which virtual handling, traction and ride tests can be performed. A fully instrumented simulator cabin combining the driver and the vehicle simulation package is developed. Different vehicle configurations are simulated during typical sever manoeuvres which reflects the robustness and fidelity of the devised simulator.

scholarly journals Assessment of a rail vehicle running with the damaged wheel on a ride comfort for passengers

2018 ◽  
Vol 157 ◽  
pp. 03004 ◽  
Author(s):  
Ján Dižo ◽  
Miroslav Blatnický ◽  
Stasys Steišūnas ◽  
Blanka Skočilasová
Keyword(s):  
Ride Comfort ◽  
Railway Wheel ◽  
Rail Vehicle ◽  
Rail Vehicles ◽  
Dynamic Analyses ◽  
Wheel Flat

In certain conditions rail vehicles wheels can be during operation damaged. Then, the profile of wheels is no longer circular, but it is changed depending on the type and severity of defects. When such rail vehicle with the damaged wheel operates, the quality of a ride comfort for passenger is degraded. This article is focused on the assessment of ride comfort for passenger based on results obtained from dynamic analyses. Simulations and calculations were carried out in commercial multibody software. In our research we considered one type of the railway wheel untrueness – wheel-flat. This type of wheel damaging is relatively common and has such influence on the ride comfort for passenger worsening, which needs to be detected and investigated.

scholarly journals PENGENALAN BAHASA TULIS BERBASIS PEMEROLEHAN UNTUK ANAK KB DAN TK

Diksi ◽  
2015 ◽  
Vol 15 (1) ◽  
Author(s):  
Tadkiroatun Musfiroh
Keyword(s):  
Field Testing ◽  
Receptive Language ◽  
Written Language ◽  
Research Subjects ◽  
Reading And Writing ◽  
Learning Conditions ◽  
The Media ◽  
Extended Field ◽  
Written Language Acquisition ◽  
Validation Testing

There are three main aspects of problems concerning the introduction ofthe written language (the language used in reading and writing activities) in playgroups and kindergartens: the method, the learning approach, and the media andsources used for the activities related to it. Inappropriateness in choosing the threeaspects will result in undesired development of the children on the whole,including their interest in reading and writing activities. Therefore, there needs tobe developed a model for introducing written language for children whichaccommodates the three aspects. A research study has been conducted with theobjective of developing and finalizing such a model and guidelines for itsapplication by means of (1) validation testing by experts and users, (2) limited fieldtesting, and (3) extended field testing.The research subjects were 107 teachers and 178 chidren in play groupsand kindergartens in the Yogyakarta Province. The data were obtained by means ofvarious methods: observation, questionnaire, interview, and documentation. Theinterview data were orthographically transcribed and then combined with fieldnotedata and data of the children's written expressions were documented by usinga scanner. The analysis was both qualitatively and quantitatively descriptive.Validity was confirmed by means of intra-rater and inter-rater techniques.The research results indicate that, after validation testing by experts andusers as well as limited and extended field testing, the model has shown an abilityto improve learning conditions, increase children's acquisition of the writtenlanguage for the related productive and receptive language activities, improvetheir symbol sensitivity, and strengthen the foundations of their reading andwriting activities. The application of the model has also improved the teachers'competence.Keywords: introducing written language, acquisition-based written language,children in play groups and kindergartens

Steady State Techniques in Creep Force Estimation: Results From Full Scale Tests of the SOAC Vehicle on a Roller Rig

1989 ◽  
Vol 111 (1) ◽  
pp. 61-68
Author(s):  
Imtiaz-ul-Haque ◽  
E. Harry Law
Keyword(s):  
Steady State ◽  
Forced Response ◽  
Full Scale ◽  
Force Estimation ◽  
Test Procedures ◽  
Creep Force ◽  
Roller Rig ◽  
Full Scale Tests ◽  
The U.S

Steady state forced response tests of the SOAC vehicle were conducted on the roller rig (Roll Dynamics Unit) at the U.S. DOT/Transportation Test Center. This paper presents the test procedures, the results of the tests, and the analysis procedures developed for the estimation of the creep coefficients. Results of the estimates are compared with theory and possible reasons for discrepancies are discussed.

Wheel-Rail Contact Characteristics on a Tangent Track Vs a Roller Rig

2012 ◽  
Author(s):  
Alexander Keylin ◽  
Mehdi Ahmadian ◽  
Mehdi Taheri ◽  
Ali Tajaddini
Keyword(s):  
Contact Mechanics ◽  
Surface Condition ◽  
Field Testing ◽  
Test Results ◽  
Full Size ◽  
Test Conditions ◽  
Roller Rig ◽  
Analytical Expressions ◽  
Roller Radius ◽  
Track Irregularities

This study derives explicit analytical expressions for comparing contact patch dimensions and Kalker’s coefficients for a wheel moving on a roller and compares the results with a tangent track arrangement. The expressions suggest that full size roller rig will underpredict Kalker’s traction coefficients (creepage forces per unit creepage) by a factor that depends on the roller radius. Studying rail-wheel contact mechanics and dynamics in the field conditions can prove to be challenging due to the difficulties in adequately controlling the test conditions that can significantly affect the results, such as track irregularities, rail surface condition, etc. Roller rigs can prove to be a useful tool for such studies. One, however, must be careful when interpreting roller rig test results because of the differences in wheel-rail contact mechanics and dynamics between the track and the roller. The findings of this study, which are consistent with other studies’ conclusions, will allow researchers to relate results with field testing.

LATERAL STABILITY ANALYSIS OF A RAILWAY TRUCK ON ROLLER RIG

1997 ◽  
Vol 21 (3) ◽  
pp. 317-326 ◽  
Author(s):  
W.H. ElMaraghy ◽  
R.V. Dukkipati
Keyword(s):  
Field Test ◽  
Test Data ◽  
Linear Models ◽  
Analytical Models ◽  
Lateral Stability ◽  
Body Dynamics ◽  
Ride Control ◽  
Freight Car ◽  
Roller Rig ◽  
Multi Body

Generic linear models were developed of a freight car (with a characteristic North American three-piece truck) on tangent track. The models were developed using the generalized multi-body dynamics software MEDYNA. Predictions were made of the theoretical linear model hunting (lateral stability) characteristics of the freight car, i.e., the critical speeds and frequencies, for five different configurations: (a) freight car on track, (b) the freight car’s front truck on the roller stand and its rear truck on track, (c) freight car on the roller rig, (d) a single truck on track and (e) single truck on the roller stand. These were compared with the Association of American Railroads’ field test data for an 80-ton hopper car equipped with A-3 ride control trucks. Agreement was reached among all the analytical models, with all models indicating a range of hunting speeds of 2% from the highest to lowest. The largest discrepancy, approximately 8%, was indicated between the models and the field test data.

Freight Car Electrically Driven Set and Release Hand Brake (EDHB)

2011 ◽  
Author(s):  
David C. Brabb ◽  
Kenneth L. Martin ◽  
Anand R. Vithani ◽  
Monique F. Stewart ◽  
S. K. Punwani
Keyword(s):  
Field Testing ◽  
Inherent Safety ◽  
Freight Train ◽  
Safety Issues ◽  
Freight Car ◽  
Future Plans

For years, American freight railroads have attempted to eliminate freight train crew injuries when applying and releasing freight car hand brakes. Currently, a person has to crank a handle or turn a wheel while in ergonomically awkward positions to apply a hand brake. If the operator slips or the brake’s mechanisms slip, injuries occur. Also, there are inherent safety issues with the climbing of ladders or steps to operate the brake and the need for going in-between cars to access the brakes. Additionally, today’s hand brakes are applied manually to varying degrees because there is no indicator to tell the crew that the hand brake is fully applied. Many times the hand brake is over applied and becomes damaged. Moreover, a hand brake that is not released upon train movement leads to wheel flats that damage the car, lading, and the track. Wheel set replacement is one of the most costly remediation activities on the railroad and damaged track adversely affects equipment and operations. With the objective of reducing or completely eliminating the issues mentioned above, the Federal Railroad Administration (FRA) has sponsored the development of an ‘Electrically Driven Set & Release Hand Brake’ (EDHB). Under this effort, Sharma & Associates, Inc. (SA) has conducted research into related concepts/products conceptualized and evaluated different arrangements selected a promising concept and developed a prototype. Functional laboratory demonstration tests have been conducted on the prototype. Future plans include working with the industry in developing and implementing performance and testing specifications for the EDHB, and validating the design through lab and field-testing.

Lateral Stability Behavior of Railway Freight Car System With Elasto-Damper Coupled Wheelset: Part 1—Wheelset Model

1987 ◽  
Vol 109 (4) ◽  
pp. 493-499 ◽  
Author(s):  
A. K. W. Ahmed ◽  
S. Sankar
Keyword(s):  
Lateral Stability ◽  
Conventional System ◽  
Stability Behavior ◽  
Rail Vehicle ◽  
Railway Freight ◽  
Linearized Stability ◽  
Freight Car ◽  
The Stability ◽  
The Mathematical Model ◽  
Railway Freight Car

A general model of single rail vehicle wheelset with elasto-damper coupling between the wheels, has been developed as a first step in developing a railway freight truck model with elasto-damper coupled wheelset (EDCW). By choosing different coupler parameters, various stiffness-damper combinations, as well as rigid axle (conventional wheelset) could be simulated. The mathematical model of EDCW has been validated by comparing the model under limiting cases with those of published results for conventional system. In this paper, the results of linearized stability analysis of EDCW model on tangent track are presented and discussed. The investigation showed that wheelset coupler parameters have significant influence on the stability behavior of the wheelset, and there is an optimal coupler parameter which can improve the wheelset critical speed over the conventional system.

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