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ME270 Prof. Granda. Vehicle Crash Test Lab Justin Otero Fall 2007. First thing done was to create a bond graph then enter into CAMP-G software. I | SF—1—-0—-1—-0—-1—-I | | R—1--C R--1--C.
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ME270Prof. Granda Vehicle Crash Test Lab Justin Otero Fall 2007
First thing done was to create a bond graph then enter into CAMP-G software I | SF—1—-0—-1—-0—-1—-I | | R—1--C R--1--C
Causality and Equations were then derived from the bond graph and verified in CAMP-G SF1=f1 f2=f1 e5=Q5/C5 f7=P7/I7 f8=f7 e11=Q11/C11 f13=P13/I13 f6=f7 f12=f13 f3=f2-f6 f4=f3 f5=f3 f9=f8-f12 f10=f9 f11=f9 dQ5=f5 dQ11=f11 e4=f4*R4 e10=f10*R10 e3=e4+e5 e6=e3 e9=e10+e11 e12=e9 e13=e12 dP13=e13 e2=e3 e8=e9 e1=e2 e7=e6-e8 dP7=e7
Using MATLAB the variables were designated as; • e=force • f=velocity • Q=displacement • P=momentum • R=damper value • C=spring constant • I=mass
Using MATLAB a simulation was run and two graphs were plotted using the given variables.
The values were modified to run a simulation of a vehicle crashing at 25mph and 55mph. • Graphs were plotted to get the displacement and forces being exerted on the dummy.
A Simulink diagram was created in MATLAB to verify the System State space equations.
Here is the comparison of the MATLAB campgnum.m to the simulink scopes.
The best design for a bumper and seat belt combination to survive a crash at 55mph. Bumper: Seat Belts: Spring Constant = 500K Spring Constant = 150K Damper Value = 50K Damper Value = 25K These Values produce results no greater than 2743 lbs of force per seatbelt and 81 cm of displacement for the dummy.