liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Road Slope Estimation
Linköping University, Department of Electrical Engineering, Automatic Control.
2010 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

Knowledge about the current road slope can improve several applications in a heavy-duty vehicle such as predictive cruise control and automated gearbox control. In this thesis the possibility of estimating the road slope based on signals from a vehicles air suspension system has been studied. More specifically, the measurement consists of a pressure signal measuring the axle load, and a vertical distance sensor.

A variety of suspension systems can be mounted on a Scania truck. During this thesis, two discrete-time models based on two different rear axle air suspension systems have been proposed. The models use the effect of alternating axle load during a change in the road slope and the estimates are computed using an extended Kalman filter.

The first model is based on a rear axle suspension known as the 2-bellow system. This type of suspension is strongly affected by the driveshaft torque, which results in a behaviour where the rear end is pushed upwards and thus decreasing the rear axle load during uphill driving. A model was developed in order to compensate for this behaviour. Unfortunately, the estimates showed less promising results and all attempts to determine the error was unsuccessful.

The latter model is based on the 4-bellow system. This suspension system is not affected by the driveshaft torque and a less complex model could be derived. The experimental results indicated that road slope estimation was possible and with a fairly accurate result. However, more work is needed since the estimate is affected by road surface irregularities and since the algorithm requires knowledge about the vehicles mass and the location of the centre of gravity.

All the presented results have been estimated based on real data from a test track at Scania Technical Centre in Södertälje.

Place, publisher, year, edition, pages
2010. , 41 p.
Keyword [en]
Road Slope Estimation, Air Suspension, Heavy-duty Vehicle, Signal Processing, Modelling, Extended Kalman Filter
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:liu:diva-53884ISRN: LiTH-ISY-EX--10/4307--SEOAI: oai:DiVA.org:liu-53884DiVA: diva2:293213
Presentation
(English)
Uppsok
Technology
Supervisors
Examiners
Available from: 2010-02-11 Created: 2010-02-09 Last updated: 2010-03-30Bibliographically approved

Open Access in DiVA

fulltext(4519 kB)1719 downloads
File information
File name FULLTEXT02.pdfFile size 4519 kBChecksum SHA-512
7649f310872594a42769703b3dfe65e931ec631c84557bcafd0d1be3a12bb7770bee4be8418aa4ecb6ee4e45b532255a0a55b26b80c4d5e196dc59f62c385214
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Larsson, Martin
By organisation
Automatic Control
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 1724 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 911 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf