STISIM Drive (SDL) - RT - Reaction Time
This is a very specialized
event for measuring a driver's reaction time. The RT event simply displays a
large image of a stop sign (or other image if you prefer) in the center of the screen.
The driver is then supposed to press the brake pedal as fast and as hard as
possible. You can then setup the scenario to collect data and get the driver's
reaction time and stopping distance. STISIM Drive comes with a PDE file named ReactionTime.PDE that does this for
you and is explained in the example below. If you use the ReactionTime.PDE
file, the average reaction time and stopping distance (in case you do it
multiple times in a single run) will be displayed as part of the run summary. It should be noted that while the
reaction time image is being displayed, the hood and rear view mirrors will be
turned off. After the image has been displayed for the specified duration, the
hood and mirror will be restored.
EVENT PARAMETERS:
|
PARAMETER 1: |
Flag specifying what measure will be used to turn the image off: 0 - Time
(seconds) |
|
PARAMETER 2: |
Duration of the image in either seconds or feet based on parameter 2 above. |
|
PARAMETER 3: |
Name of the image file that will be used. This must be located within the STISIM Drive root directory. In the ReactionTime.PDE file the file that is used is Data\Miscellaneous\RTStop.3ds, however you can use any image you desire. |
EXAMPLES:
Scenario:
1000,PDE,C:\STISIM\Projects\ReactionTime.PDE,1
PDE:
0,BSAV,1,.04,Brake reaction
data #@1: (Time u x ax),1,4,6,13
0,RT,0,10,Data\Miscellaneous\RTStop.3ds
500,ESAV
The first line under the
heading Scenario is used to call the ReactionTime.PDE event, while the 3 lines
under PDE heading are directly from the ReactionTime.PDE file that is included
with STISIM Drive and can be found in the Projects directory. By including the
call to the ReactionTime.PDE file, you can have STISIM Drive provide an average
reaction time and stopping distance. The PDE call is straight forward, at 1000
feet the program calls the PDE file named ReactionTime.PDE and passes it
a parameter of 1 to the PDE. Within the PDE file the first line tells the
program to begin saving data as soon as the PDE file is called (0,BSAV). The
data will be saved as a function of time and will be saved at .04 second (or as
close as possible to that) intervals (1,.04). The next BSAV parameter is very
important because it labels the block of data that will be collected. In this
case the label will be "Brake reaction data #1: (Time u x ax)". In
this case the @1 that appears in the PDE file will be replaced by the 1 that
was passed to the PDE routine. In order for STISIM Drive to compute the
reaction time and stopping distance it searches the final STISIM Drive data
file looking for blocks of data labeled "Brake reaction data",
therefore you should not change the label and if you want to use the RT event
in other ways and want the program to compute the reaction time for you, you
will need to save the data in a block with a label that begins "Brake
reaction data". The data that will be saved in this block are specified
with the final 4 variables (1,4,6,13). In this case the data includes time,
vehicle speed, distance, and longitudinal acceleration.
That covers the BSAV event.
The next line specifies the reaction time event. The start of the reaction time
event should be the same as the BSAV event. This way you can accurately measure
what the reaction time was because it starts at the same time the data save
begins. In this case the symbol will be displayed for 10 seconds (0,10) and
then will disappear. The image that will be displayed is contained in the
RTStop.3ds file.
Finally, the last line simply tells the program to stop taking data after the vehicle has traveled 500 feet.