Example: Pole Impact inputs


The following example includes the cards required to simulate a 10 inch radius pole located at space-fixed location X = -13.5 feet and Y = -51.0 feet.

In this instance, the vehicles are not in proximity to the pole until 5.2 seconds, so to conserve computer resources, the Pole option is not activated until simulated time = 5.20 seconds.  Users are cautioned against setting an inappropriate start time for the pole option. The pole option start time option was created to conserve computer resources. At the time the pole option is activated, the program changes the integration time increment to the DTCOLL time increment (recommended as 0.001 sec. or less for pole impacts).  If you are simulating a vehicle to vehicle impact or a pre-impact spinout which is followed by a pole impact, you can delay the beginning of the Pole impact option scan (and use of the small integration time increments) until the vehicle is in proximity to the pole. (Note that the collision scan logic is unaffected by the use of the Pole impact option so the program may change to and from the DTCOLL time increment during the run based on the collision scan logic.)  Users are cautioned that the vehicle should not be in contact or interfering with the pole at the initial start time of the pole option.

The following are the inputs cards for the pole impact:

5.20    10.0    5.0     -162.   -612.   1.      1.                            16

2000.   250.    -0.000862.017   0.0     100.    -1.0    10.     10.           19


An echo of the inputs for the pole impact is as follows:


                SMAC POLE OPTION INPUTS:                                   

                  POLE MONITOR START TIME =   5.200 SEC.                          

                  END TIME FOR POLE SCAN  =  10.000 SEC.                          

                  POLE OPTION FLAG        =    5.(=0 NONE,=5 POLE FIXED IN SPACE)

                  POLE X LOCATION IN SPACE=-162.000 INCHES                                     

                  POLE Y LOCATION IN SPACE=-612.000 INCHES                                    

                  ISIDE (1=RSIDE,-1=LSIDE)=    -1

                  RPOLE,       POLE RADIUS=   10.00 INCHES

                  SDEF,SATURATION DEFLECTN=   10.00 INCHES

                  K1,    LOADING STIFFNESS= 2000.00 LB/IN

                  K2,  INLOADING STIFFNESS=  250.00 LB/IN

                  RHO,    RESTITUTION TERM=-.000860

                  GAMMA,  RESTITUTION TERM=   2.017

                  PMU,   POLE/VEH FRICTION=    .000

                  OMEGT,FRICTION NULL BAND= 100.000 IN/SEC

The inputs for the pole impact crush loading and unloading stiffness (2000 lb/in and 250 lb/in), restitution terms, and saturation deflection (10 inches) are based on a generalized  review of full-scale frontal pole impact tests. If you have available to you pole impact tests which include a specific vehicle being simulated, it is recommended that you set up and simulate the full scale pole impact test to refine the inputs for your particular vehicle. In general, the inputs should not vary greatly from these generalized inputs except in the loading and unloading crush stiffness (which determines the rate of loading and unloading during the pole impact) and the saturation deflection (which limits the peak g's during the pole impact).