This Is AuburnElectronic Theses and Dissertations

Development of a Custom Data Acquisition System for the Study of Vehicle Dynamics in Longer Combination Vehicles


This thesis details the development, deployment, and verification of a custom data acquisition system for the purpose of studying vehicle dynamics in a triple trailer Longer Combination Vehicle (LCV). In addition to the data acquisition the thesis details the simulation efforts that were undertaken to both verify the experimental data as well as assess the stability of the vehicle itself. The research was part of an effort to assess the viability of widening the available roadways that are currently accessible to LCV trailers. This project undertook the task of fully instrumenting a triple trailer LCV with a package of more than 35 sensors and implementation of a custom Data Acquisition System (DAQ) to log over 200 channels coming from the aforementioned sensors. Once outfitted with the sensor package, the LCV was put through a variety of dynamic tests including lane changes and constant radius turns in an attempt to capture various dynamic characteristics of the vehicle. A series of simulations were run to match the maneuvers undertaken during the experimental phase. That data was then compared to ensure that the simulation did indeed agree with the experimental data. Once in agreement the simulations were expanded to speeds that were not able to be achieved experimentally due to safety concerns. The last element of the simulation was a comparison between the LCV triple and a standard double trailer heavy truck as seen on the highways today. The LCV under test behaved as expected given the prior research into LCV dynamics. Additionally the simulation and the experimental data were shown to agree. The simulation exposed the instability of the vehicle at speeds easily expected on the highways. When comparing the triple LCV to the double it was shown that at lower speeds the first four units behaved similarly, but as the speeds increased the effects of the third trailer were shown in the responses of the second. Finally this thesis shows that there is a need for heavy precautions before allowing triple LCV to traverse the highway roads. At lower speeds the vehicle is safe but increasing that speed to that of the standard highway speed shows that the vehicle will respond with undesirable outputs.