1. Car Rollover Test Name: Antonio Sevilla Course: ME 272 FEA Prof. Jose Granda Date: 12-20-06

2. Problem Statement To determine the velocity at which a vehicle must be traveling to completely rollover after hitting a curve sideways. To determine the velocity at which a vehicle must be traveling to completely rollover after hitting a curve sideways.

3. Parameters Test vehicle was constructed in Solidworks and then the model was transferred to Visual Nastran 4D for analysis. Test vehicle was constructed in Solidworks and then the model was transferred to Visual Nastran 4D for analysis. A curb was placed in front of vehicle to get the vehicle to rollover. A curb was placed in front of vehicle to get the vehicle to rollover. Curb dimensions are 6” X 10” X 190” (H x W x L). Curb dimensions are 6” X 10” X 190” (H x W x L). A velocity was applied to the center of mass of the vehicle. A velocity was applied to the center of mass of the vehicle. Vehicle mass: 2000 lbm Vehicle mass: 2000 lbm Coefficient of friction:.5 Coefficient of friction:.5

4. Simulation at V=15 mph Click on the picture (If video doesn’t play you can find the simulations in the video folder.)

5. Simulation at V=20 mph (If video doesn’t play you can find the simulations in the video folder.)

6. Simulation at V=25 mph (If video doesn’t play you can find the simulations in the video folder.)

7. Results From the simulations we can see that at V= 15 mph, the car only tilts a little but it does not flip. From the simulations we can see that at V= 15 mph, the car only tilts a little but it does not flip. At V=20 mph, the car flips on its side and then lands back on its wheels. Therefore, full rollover is not accomplished. At V=20 mph, the car flips on its side and then lands back on its wheels. Therefore, full rollover is not accomplished. At V=25 mph, the car flips completely and lands on its roof. Complete rollover is accomplished. At V=25 mph, the car flips completely and lands on its roof. Complete rollover is accomplished.

8. Results: Graphs The following graphs show the velocity (top) and acceleration (bottom) of the vehicle vs time. The following graphs show the velocity (top) and acceleration (bottom) of the vehicle vs time. The results show how the Vx, Vy and Vz components of velocity and accel. change for a car traveling at 25 mph. The results show how the Vx, Vy and Vz components of velocity and accel. change for a car traveling at 25 mph.

9. Results: Von Mises Stress The max. Von Mises stress on the front right suspension on the vehicle at 25 mph was 8.60X10 5 psi. The max. Von Mises stress on the front right suspension on the vehicle at 25 mph was 8.60X10 5 psi. The picture to the right shows the suspension after the collision. The picture to the right shows the suspension after the collision.

10. Results: Von Mises Stress at 25 mph (left), 15 mph (top) and 20 mph (bottom)

11. Conclusion Given a vehicle with a mass of 2000 lbm, a coefficient of friction of.5 and a standard 6 inch curb, we find that it requires a velocity of 25 mph to cause the vehicle to completely rollover and land on its roof. Given a vehicle with a mass of 2000 lbm, a coefficient of friction of.5 and a standard 6 inch curb, we find that it requires a velocity of 25 mph to cause the vehicle to completely rollover and land on its roof.