Analys av fordonsbeteende för att hitta kriterier för styrrobot-tester
Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
To test and to verify the properties of a new product, such as the concept of a new car or a tire model, is an important part in modern automotive technology and industry. Today the testing of winter tires is almost entirely done by human drivers. By adopting the use of a steering robot in tire tests several advantages can be achieved such as repeatability and time saving in the way that it is not necessary to mark out the test track with cones. But is it possible to use a steering robot in tire tests during winter, and how to evaluate the tests? Which parameters regarding vehicle dynamics can be useful for the evaluation of a steering robot? To answer these questions different tests was performed with a car and at the same time data was logged from the vehicles CAN-bus. In a simulation program for cars the same type of tests was executed to get data that could be compared to the real life tests. These data was then analyzed and evaluated to find suitable criteria that could be useful in the evaluation of a steering robot and tire tests. Parameters such as cornering stiffness, slip angles and lateral forces can be analyzed for tire tests because of the influence they have on the dynamics of the vehicle. The slip curve for the tire can show the correlation between these such as which lateral force gives a certain amount of tire slip and the rate of change for tire slip relative to change in lateral force. These criteria can indicate variances when comparing different tires. For analysis of the criteria’s such as yaw rate response, Matlab tools were developed to make it fast and easy to analyze and visualize the raw test data. With a human driver it is more difficult to maintain consistency than with the use of a steering robot, i.e. if the driver is supposed to give a 90 degree input to the steering wheel there will often be a tolerance of several degrees. In this case a steering robot would give a much more consistent input, but on the other hand it could be desirable to get the steering robot to act more human under certain circumstances.
Place, publisher, year, edition, pages
2011. , 77 p.
IdentifiersURN: urn:nbn:se:ltu:diva-47208Local ID: 4c6f0c83-be49-461f-ab41-452beb37ab6bOAI: oai:DiVA.org:ltu-47208DiVA: diva2:1020528
Subject / course
Student thesis, at least 15 credits
Automotive Engineering, bachelor's level
Validerat; 20110205 (anonymous)2016-10-042016-10-04Bibliographically approved