Center of Gravity Height Analysis

 

In this Kineticorp research video, Neal Carter, Martin Randolph and Nathan Rose calculate the Center of Gravity Height Analysis of a large SUV. This analysis will aid in the reconstruction of roll over cases and other applicable instances.

“When we are analyzing a roll over case, for instance, that is the type of crash where we would use the center of gravity height analysis.” – Nathan Rose

Video Transcription

Often times, when we need to know the center of gravity for a vehicle, it’s sufficient for us just to estimate that with equations or data from the literature. But, sometimes we get cases where we need to know it more precisely and in those cases we can do an experiment like this. So, today we have an exemplar vehicle and we are going to go through a procedure to determine where the center of gravity for this particular vehicle is. With this process we’re looking at how changing the angular orientation of the vehicle shifts weight. We are going to elevate the front end of the vehicle. When we do that, weight of the vehicle will shift to the back axle and from that weight shift we can calculate the center of gravity height. In this procedure, we’re using our 3D laser scanners to document the motion of the vehicle body in relationship to the vehicle suspension. As we elevate the front end of the vehicle, not only does weight shift, but the body also moves relative to the suspension and we need to quantify that in our procedure. We often need to know where the center of gravity of the vehicle is so that would be the center of gravity, where it is between the wheels, front to back and then also, the height of the center of gravity. And often times that’ll play into our analysis, if we’re doing a simulation especially, in terms of how the vehicle moves in response to driver steering inputs; where the center of gravity could play a role in that. When we are analyzing a rollover crash, for instance, that is the type of crash where we would use the center of gravity height in our analysis.