Master of Science in Engineering, Youngstown State University, 2025, Department of Mechanical, Industrial and Manufacturing Engineering

A continuously variable transmission (CVT) is a type of transmission used commonly in small engine racing such as snowmobiling, go-karting, or in Society of Automotive Engineers (SAE) Baja racing. These transmissions allow for a constantly varying gear ratio while driving, without requiring the driver to shift gears manually. The continually changing ratio adapts well to varying course conditions such as frequent stops and starts, turns, and jumps. CVTs must be properly installed and tuned to reach their highest level of performance, which is a common difficulty for these complex systems. A MATLAB code has been developed that characterizes the torque, horsepower, and shift profile of a Gaged GX9 CVT. This predictive model may be used to select a tune for a vehicle and evaluate its performance without requiring extensive test time on a track. Multiple setups of the primary and secondary were analyzed, including different primary and secondary springs, flyweights, and ramps. The numerical characterization of torque, horsepower, shift curve, and acceleration has been validated experimentally, through the use of an inertia dynamometer, Kohler CH440Pro 14HP engine, and DynoMiteTM analysis software. Theoretical comparison was completed using free body and kinetic diagrams of the forces acting in the system, which were entered into a MATLAB code.   A new inertia dynamometer system has been installed within Youngstown State University's (YSU) engine laboratory, providing a hands-on application of methods learned in the classroom for students. The new installation has been used by several student groups to date. An operator's manual for the system focusing on safety and proper machine operation has been developed to aid in correct usage of the dynamometer. The new installation and numerical modeling completed has also been used to develop a laboratory for mechanical engineering students in the Dynamic Systems Modeling (DSM) class. Within the lab students will learn t (open full item for complete abstract)

Committee: C. Virgil Solomon PhD (Advisor); Hazel Marie PhD (Committee Member); Fred Persi PhD (Committee Member) Subjects: Applied Mathematics; Automotive Engineering; Mechanical Engineering

MS, University of Cincinnati, 2006, Engineering : Mechanical Engineering

The task of tuning an engine from scratch can be very time consuming and difficult if the right equipment is not utilized. Several different types of dynamometers with feedback control systems exist that enable a tuner to simplify the process. However, most of these systems are designed for specific applications and engines. Typically, the proper equipment is determined based on the budget and requirements of the tuner. The most common engines for Formula SAE (FSAE) cars are usually motorcycle engines or something similar. Unlike the usual car engines, which have separate transmissions, these engines and transmissions are built together. A complete custom engine dynamometer stand and corresponding connection between the transmission output shaft and the dynamometer is necessary.

Committee: Dr. Randall Allemang (Advisor) Subjects: Engineering, Automotive