Reconstruction of an Actual Vehicle Rollover as a Special Project in an Undergraduate Dynamics Course

Abstract

The reconstruction of a vehicle rollover was assigned as a special group project in an undergraduate course in dynamics at Grand Valley State University. The students were provided with a diagram documenting the path of an actual vehicle rollover. Using the principles learned in the dynamics course, the students were tasked with determining the translational velocity of the vehicle throughout the event, including the pre-trip, trip, and tumbling phases. The project also required the students to calculate the yaw rate prior to trip and the roll rate during the tumbling phase of the event. With the translational and rotational velocities along with the relevant geometry of the vehicle, the students were able to determine the trajectories of a hypothetical occupant ejected from the vehicle at different points in time throughout the rollover and estimate the locations where the occupants would come to rest. The data for this rollover came from a test conducted on a rural highway by Woolley Engineering Research Corporation. A 1994 Nissan Pathfinder was towed to highway speed before being released, at which point an automated steering controller steered the vehicle through a series of maneuvers that resulted in rollover. The test was documented with on-board high-speed instrumentation and two off-board high-speed video cameras. This instrumented test allowed for the direct comparison of the students' reconstructions of the rollover event with what actually occurred. This course project gave the students the opportunity to demonstrate that the principles taught in their undergraduate dynamics course can be used to effectively and accurately analyze a real-world event. In a student survey conducted at the end of the course, 95% of the students reported that they felt that completing this project enhanced their understanding of the principles of kinematics and dynamics that were taught in the class. OverviewOne of the key challenges in undergraduate engineering education is helping students understand how the theoretical principles they learn in their coursework can be applied to solving real-world engineering problems. This can be especially challenging in a core mechanical engineering course like dynamics. As the students work through problem set after problem set, they can find it difficult to see how solving the contrived, simplified problems from the book actually relates to analyzing dynamics in the "real world." To help the students begin to see how dynamics is applied by practicing engineers, a special group project was assigned to two sections of an undergraduate dynamics course taught at Grand Valley State University. In groups of two or three, the students were given the opportunity to demonstrate that the principles taught in this dynamics course can be used to effectively and accurately analyze a real-world event such as an actual on-road vehicle rollover.