Acceleration/velocity display vectors in msmac Animation program

         

Before we can run SMACTHP to determine the acceleration and velocity of various locations on the vehicle, we must first run msmac. To run msmac,

•    click on the  button or choose Menu ->Run->msmac

•    After msmac runs the static graphics program runs and displays a summary of the results.

•    Press ESC to close the static graphics display.

 

Now lets run the smac animation.

•    Menu->Run->msmac Animation

•    Click OK on the Run dialog and then once the smac animation window opens, press the space bar to run the animation.

The animation will run quickly to near the point of impact and then slow and display every 0.001 seconds during the collision and then speed up again after the impact.

You will also notice velocity and acceleration vectors like that depicted below:

Figure 73 SMAC Animation display with acceleration and velocity vectors

 

 

 

The animation displays like this because of the following inputs in the smac animation input (SA5) file:

Display time increment is 0.0

So each time increment is displayed from the smac run. If you change the display to 0.01 in the SA5 file it will display only every 0.01 seconds so you will not get the slower display during the collision.

The acceleration and velocity vectors are displayed

The is due to the inputs in the SA5 file as follows:

 

Option=vehob

# Acceleration vector display

# For vehicle 1: Accelerations > 1, a vector 0.2*ACC long will be displayed

# For vehicle 2: Accelerations > 1, a vector 0.2*ACC long will be displayed

# 1st set color to yellow for vehicle 1 display

4.0     14.

# Now set option to draw in vehicle 1

1.    0.   0.    21.  .3

1.    30.  20.   21.  .3

1.    -30. -20.  21.  .3

# now set color to white for vehicle 2 display

4.0     10.

# Now set option to draw in vehicle 2

2.    0.   0.    21.  .3

2.    30.  20.   21.  .3

2.    -30. -20.  21.  .3

9999.

Further discussion of the vehob displays are discussed in the graphics and animation manaual and also in Example OCC1

 

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Running SMACTHP