Date of Award
Doctor of Philosophy
Engineering Science and Mechanics
The primary objective of this research was to theoretically investigate what effects the spring-damper suspensions have on pitch, vertical and roll motions of three-wheeled all-terrain vehicles. Model A, which is a six degrees-of-freedom mathematical model representing the vehicle/rider system with no suspensions, and Model B, which is a thirteen degrees-of-freedom mathematical model representing the vehicle/rider system with front and rear independent suspensions, were formulated for this study. Data measured from two commercially available three-wheeled ATVs, a 1980 Honda ATC 110D and a 1980 Kawasaki KLT 200, were used as input parameter values for Model A. Since there were no commercially available three-wheeled ATVs with front and rear independent suspensions, input parameter values for Model B were estimated based on parameter values of the two three-wheeled ATVs measured for Model A. The vehicle/rider systems were mounted with two different sets of tires, a set of three 22 x 11-8 Ohtsu tires and a set of three 22 x 11-8 Goodyear tires. Three different bump profiles of rectangular, parabolic and sinusoidal shapes were used as disturbances for the vehicle/rider systems. All three bump profiles have the same maximum amplitudes, but the base lengths of the rectangular and parabolic bump profiles are shorter than the sinusoidal bump profile. From the results of the computer simulations, plots of pitch, vertical and roll displacements versus time were generated. A plot of vertical tire forces versus time was also produced. The analyses of the plotted results have led to the major conclusion of this study that ride and handling characteristics of a three-wheeled ATV can be improved significantly if front and rear independent suspensions are present.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Teong Eng Tan
Tan, Teong Eng, "Analysis of three-wheeled all-terrain vehicle/rider system dynamics " (1984). Retrospective Theses and Dissertations. 7800.