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Development of Comfort Evaluation Tool for Analysis of Bus Structures

Bitzekis, Christofer and Swanholm, Viktor (2013) In Diploma work FME820 20131
Mechanics
Abstract (Swedish)
The automotive industry is continuously striving for reduced development cost, time to market and high quality on their products to remain market leader. This is achieved by constantly developing their simulation methods in order to attain more accurate simulation results and include more aspects of the complexity when developing a vehicle such as durability, vehicle dynamics and comfort.

This thesis was conducted at Scanias calculation department for buses with the aim of developing a method for comfort evaluation in the bus structure. There is an ambition to be able to predict the comfort of the structure with high accuracy at an early stage of the development process. This would make it possible to shorten the development time and... (More)
The automotive industry is continuously striving for reduced development cost, time to market and high quality on their products to remain market leader. This is achieved by constantly developing their simulation methods in order to attain more accurate simulation results and include more aspects of the complexity when developing a vehicle such as durability, vehicle dynamics and comfort.

This thesis was conducted at Scanias calculation department for buses with the aim of developing a method for comfort evaluation in the bus structure. There is an ambition to be able to predict the comfort of the structure with high accuracy at an early stage of the development process. This would make it possible to shorten the development time and cost by reducing the number of physical prototypes needed to verify the comfort in the final vehicle.

A literature study was initially carried out and previous knowledge at Scania regarding comfort was taken into consideration. Vehicle comfort is a complex phenomenon and thus the aim and delimitations were set to limit the complexity of the simulation model. To further delimit the study only road and powertrain induced vibrations were taken into consideration. Relevant load cases and simulation methods in both the finite element study and the multi-body simulation part was discussed and specified.

Data from previous tests conducted on a coach with weakening and stiffening modifications on its load carrying structure is analyzed to choose what frames that should be further investigated. Three different frames are chosen: stiff, weak and reference. This is to limit the processed data and to determine if the overall trends can be seen in the calculations and simulations.

The calculations performed on the finite element model, such as dynamic stiffness and transfer functions, show good correlation and tendencies when comparing to the behaviour of the vehicle in the tests.

Multi-body simulations show a more complex relationship to the measurements but some tendencies seen in the tests could also be seen in road simulator and virtual proving ground simulations. The simulation procedures for the road simulator, virtual proving ground and idle are needed to be further investigated to understand how the assumptions affects the simulation results. This is discussed and presented as future work together with limitations and possible sources of error. (Less)
Please use this url to cite or link to this publication:
author
Bitzekis, Christofer and Swanholm, Viktor
supervisor
organization
alternative title
Lastfall för Komfortutvärdering av Busstrukturer
course
FME820 20131
year
type
H2 - Master's Degree (Two Years)
subject
publication/series
Diploma work
report number
ISRN LUTFD2/TFME – 13/5025 – SE(1-57)
ISSN
ISRN
language
English
id
3910600
date added to LUP
2013-08-19 16:34:50
date last changed
2013-08-19 16:34:50
@misc{3910600,
  abstract     = {The automotive industry is continuously striving for reduced development cost, time to market and high quality on their products to remain market leader. This is achieved by constantly developing their simulation methods in order to attain more accurate simulation results and include more aspects of the complexity when developing a vehicle such as durability, vehicle dynamics and comfort.

This thesis was conducted at Scanias calculation department for buses with the aim of developing a method for comfort evaluation in the bus structure. There is an ambition to be able to predict the comfort of the structure with high accuracy at an early stage of the development process. This would make it possible to shorten the development time and cost by reducing the number of physical prototypes needed to verify the comfort in the final vehicle.

A literature study was initially carried out and previous knowledge at Scania regarding comfort was taken into consideration. Vehicle comfort is a complex phenomenon and thus the aim and delimitations were set to limit the complexity of the simulation model. To further delimit the study only road and powertrain induced vibrations were taken into consideration. Relevant load cases and simulation methods in both the finite element study and the multi-body simulation part was discussed and specified.

Data from previous tests conducted on a coach with weakening and stiffening modifications on its load carrying structure is analyzed to choose what frames that should be further investigated. Three different frames are chosen: stiff, weak and reference. This is to limit the processed data and to determine if the overall trends can be seen in the calculations and simulations.

The calculations performed on the finite element model, such as dynamic stiffness and transfer functions, show good correlation and tendencies when comparing to the behaviour of the vehicle in the tests.

Multi-body simulations show a more complex relationship to the measurements but some tendencies seen in the tests could also be seen in road simulator and virtual proving ground simulations. The simulation procedures for the road simulator, virtual proving ground and idle are needed to be further investigated to understand how the assumptions affects the simulation results. This is discussed and presented as future work together with limitations and possible sources of error.},
  author       = {Bitzekis, Christofer and Swanholm, Viktor},
  issn         = {ISRN},
  language     = {eng},
  note         = {Student Paper},
  series       = {Diploma work},
  title        = {Development of Comfort Evaluation Tool for Analysis of Bus Structures},
  year         = {2013},
}