TractorTrailer Veh Impact New
This demo, which is an update of the previous demo TractorTrailer Veh Impact. Includes some additional options.
This demo demonstrates a slow moving farm tractor which slows to a stop while an automobile and a tractor-trailer pass. On return to the travel lane the automobile slows and makes a abrupt left hand turn into the path of the tractor-trailer.
This demo demonstrates:
• Create a 3 vehicle simulation and then 3 vehicle animation,
o In the previous example, we combined the outputs of two separate smac input files to create a 3 vehicle display. In this example, we use the trailer option AND the 3rd vehicle option to create a 4 vehicle animation.
§ Note: a tractor trailer is considered 2 vehicles! Tractor & trailer, and then we also have a vehicle and a farm tractor.
o To permit the simultaneous simulation of a tractor trailer and two vehicles, we set up smac with the tractor trailer as vehicle 2, and then the farm tractor is vehicle 3, and the car is veh 1.
§ Please note: current limitation of msmac are that vehicle 1 and vehicle 2 can interact,. And vehicle 2 and vehicle 3 can interact, however vehicle 1 and vehicle 3 can not interact.
• Simulate a tractor-trailer in a passing maneuver and
• Simulate a collision between an automobile and a tractor trailer.
This advanced sample uses many options:
• The Tractor Trailer Option for m-smac for vehicle 2 only!
o In earlier versions of msmac, a tractor trailer could only be used for vehicle 2 if vehicle 1 also had a tractor trailer. We have now added the ability to simulation a tractor trailer with vehicle 2 alone.
• The 3 vehicle simulation option of msmac
• Msmac now allows you to simulate 3 vehicles
• The Include Option to include external files in the smac Animation (mGraphics) and smac Graphics (msmacgr) input files.
o These are covered in the TractorTrailer Impact project.
Detailed instructions:
• Open Project TractorTrailer Veh Impact New
• Select Project menu -> Open (from Demos folder) ->Tractor Trailer-Vehicle Impact-> TractorTrailer Veh Impact New
• The Project file is opened and file TractorTrailer Veh Impact new.si5 is opened.
The following files are contained in sample project: TractorTrailer Veh Impact New and are to be used as a part of this sample demonstration::
TractorTrailer Veh Impact New .si5 m-smac input dataset for tractor-trailer/vehicle impact
TractorTrailer Veh Impact New.sg5 smac Graphics (msmacgr) input dataset for project
TractorTrailer Veh Impact New.sa5 m-smac Animation input dataset for 3 vehicle view
TractorTrailer Veh Impact New.sce - Scene Include file for smac Animation (mGraphics) which includes scene graphics objects
Step 1 : In this example, we setup the following vehicles:
Veh1 – this is a simulation of a vehicle performing a passing maneuver around a slower moving farm tractor, and then it slows and turns into a parking lot to the left.
o The input cards required for vehicle 1 are
o msmac input cards 2,4,6,8,10
Veh2 – Vehicle 2 is a tractor trailer which is following vehicle 1
o note that in the previous input files, the vehicle identifications were reversed
o msmac input cards required for the tractor trailer as vehicle 2 are
o msmac input cards 3,5,7,9,11,21,23
o on card 3, the card containing the positions and velocities of vehicle 2, a flag is set in field 7.
o Cards 21 and 23 are used to define the properties of the trailer attached to vehicle 2
Veh3 – Vehicle 3 is the slow moving farm tractor.
o The definition of vehicle 3 is on msmac input cards 52,54,56,58,60
o Card 98 is used to permit the interaction of vehicle 3 and vehicle 2, and we have included this input card. However it is not being used.
Step 2: run m-smac for the four vehicle run:
o Open the Project Menu, Select the file: TractorTrailer Veh Impact New .Si5
o Note the following changes to the inputs for tractor-trailer option:
o Run m-smac
o After completion of the m-smac simulation, you will note that the smac Graphics (msmacgr) output displays is very small.
§ Recall that you can use your Page Up key to interactively increase (zoom) the scene.
§ Try pressing the key several times.
§ To increase the amount of zoom, also try hold down the Ctrl key while pressing the Page Up key. The effects of a single key press are increased. If you hold down the Alt key while pressing a key, the effects of the key action are diminished. This effect occurs with both the smac Animation (mGraphics) and smac Graphics (msmacgr) programs.
§ Upon completion Press the <esc> or <1> key to return to Medit
Step 3: Run the m-smac Animation
§ Open the Project Menu, Select from the files list the file: TractorTrailer Veh Impact New.SA5
§ Once the file is opened, to run you can
o Click on the Run Button or
§ Or to run the animation without opening the file,
o Select Menu Run, Item m-smac Animation
§ Once the graphics screen is displayed, Press space bar to view in continuous animated form.
o You will note that the graphics automatically pans and zooms with the action.
o This is an example of the IORIGINMOV=6 option. Interactively you can change to this option by pressing the F12 key. While viewing the animation also try pressing the F9 key and view the effects, Then also try the F10, F11 and F12 keys.
o Press the PageUp & PageDown keys to enlarge/reduce the vehicle sizes on the screen, use the arrow keys to move the origin to left/right up/down. You will note that with the F12 key (IORIGINMOV=6) option that the zoom and pan keys do not change the view.
o Also right click the mouse to bring up the pop-up dialog. You will find these and many other commands available on the pop-up dialog.
o Return to medit
Some additional Notes
o There are two different ways to display the truck tires, duals and tandem axles.
o In the msmac input file and in the graphics file
o Defining dual and/or tandem inputs in the msmac input file
o A new option added to msmac is to allow the display of tandem, duals and alternative tire display with msmac input card 24
o Open TractorTrailer Veh Impact New.Si5 (see Figure 77 below)
o This card defines the dual and tandem inputs.
o For vehicles with duals and/or tandems, the options wheel radius defined in field 9 is used.
Figure 76 input card 24, duals & tandem axle inputs
o Defining duals and/or tandems in the graphics file
o The TractorTrailer Veh Impact file used the graphics options to display the tandem and duals.
o Note: If you use input card 24, these options are not required! However you may use them for additional flexibility in the display
o If you open and of the Sa5 or SG5 files in the TractorTrailer Veh Input projects, you will notice the following inputs:
OPTION=TRACKDUALS1=1.2
OPTION=TRACKTANDEM1=4.
OPTION=TRACKDUALS3=1.2
OPTION=TRACKTANDEM3=4.
OPTION=TIRERADIUS1=1.5
OPTION=TIRERADIUS2=1.0
OPTION=TIRERADIUS3=1.5
OPTION=TIREWIDTH1=0.6
OPTION=TIREWIDTH2=0.4
OPTION=TIREWIDTH3=0.6
o These graphics options are used to set the tire duals, tandem and radius display.
o The vehicle number is indicated just before the = sign, and the value for each variable is displayed in feet.
o These are commented out in the TractorTrailer Veh Input New project by placing a # in the 1st column since they are specified in the msmac input file, input card 24 and therefore redundant.
3 Vehicle Simulation