In this tutorial task, you'll learn how to use A* navigation to prevent the patients and staff
members from walking through objects and the floor plan walls. With A* navigation, you can
designate where the patients and staff members can walk and where they cannot.
When you're finished, your simulation model should look similar to the following image:
Step 1 Add A* Dividers
In this step, you'll add some A* dividers to the model. A* navigation is a tool that
calculates the shortest path a person can use when walking from one object to
another. You can place dividers to prevent a person from walking through an area that they
shouldn't walk through (such as walking through an object or the wall of a room). The A*
Navigator will take these dividers into account when calculating the best path for a person
to travel. See
Working
With A* Navigation for more information.
When you're finished adding the dividers, the model will look similar to the following
image:
To add A* dividers:
Make sure the 3D model is open and active. In the Library under the
A* Navigation group, drag a
Grid object into the model.
Click the A* Grid (the large blue bar that surrounds
the A* dividers) to select it.
In Quick Properties in the Node Spacing box, delete the
current number and type 0.50 instead. Notice that the dividers and grid
lines will become smaller.
Use the red sizer arrows to resize the grid around the floorplan.
Make sure the 3D model is open and active. In the Library under the
A* Navigation group, click a
Divider object to enter Create Dividers mode. Your mouse
pointer will change to the Dividers icon
to show that you are in Create Dividers
mode.
Find the position in your simulation model where you want to place the beginning
corner of a divider. When you click that position in the model and start moving the
mouse pointer in a different direction, you'll notice that it begins creating a divider.
Reposition the mouse pointer until the divider's end is at the approximate length,
angle, and radius you want it to be relative to the start. Click the mouse again to
finish creating the divider. Press Esc to exit Create Divider mode.
These dividers will act as walls in the simulation model. Start by creating the
outer walls on the floor plan (the ones surrounding the whole building). If you need to
move or resize a divider, click the end points and drag them to a different
position.
Notice that when you added the dividers, an A*
Navigator was automatically added in the center of your simulation model. (It
looks like a blue A with a golden star next to it.) Drag the A*
Navigator to a different area, placing it somewhere outside the floor
plan.
Before adding dividers to the interior walls of the floor plan, double-click the
A* Navigator to open its properties window. On the
Visual tab, check the Show Grid
Nodes checkbox. Click
the OK button to save changes and close the window.
Add more dividers for the interior walls of the building. Don't worry about putting
the dividers exactly over the floor plan's walls. It's more important to try to put
dividers in between the yellow A* grid lines if possible. These dividers will prevent
movement from one point on the grid to another so it will work better if placed in
between the grid rather than over it.
Now that you've added dividers, you don't need the yellow gridlines any more.
Double-click the A* Navigator to open its properties
window. On the Visual tab, uncheck the
Show Grid Nodes checkbox. Click the
OK button to save changes and close the window.
Now that you've added A* dividers, it's time to add the 3D objects in the model to the A*
navigation system. You'll add the objects in the next step.
Step 2 Connect 3D Objects to the A* Navigator
In this step, you'll connect most of the model's objects to the A* Navigator. By
connecting location and prop objects to the A* system, it creates a small area of space around the
objects that staff and patients will not be able to walk through. Connecting staff members to the A*
system tells them to use A* for navigating around the model. You'll also learn how to
check 3D object's travel thresholds in order to prevent any strange behavior when the 3D
objects are using the A* navigation system.
To connect the 3D objects to the A* Navigator:
Press and hold the A key to enter connection mode. When you are in connection mode,
your mouse pointer will change to a plus sign with a chain link symbol next to it:
Once you are in connection mode, click the A* Navigator.
Click Nurse Station B1 to create a connection between the two
objects.
These next steps will demonstrate another method for adding members to the A*
navigation system. Double-click the A* Navigator to open
its properties window.
On the Setup tab in the
Members group, make sure that All
Members is selected as the current member view.
Click the Add button
to open a menu of all the objects in the
model organized by their type.
Click the Locations, Multilocations,
and Staff categories. Then click the Select
button. Notice that all the objects of those types now appear in the members list.
Step 3 Adjust for Travel Threshold
In this step, you'll display the travel threshold for several object in the model and adjust their
position accordingly. The Show Travel Threshold checkbox that we use
in this step is a visual display of the logic that A* uses under the hood.
To show object travel thresholds and adjust for them:
Double-click the A* Navigator to open its properties window.
On the Visual tab, check the
Show Travel Threshold checkbox. Click the
OK button to save changes and close the window.
Click the ExamTable1 object to select it. Notice that you
can now see the object's travel threshold, represented by several red and blue dots
surrounding the object.
Check to ensure that the none of the red travel threshold dots go beyond the
dividers. (It is fine if the blue dots extend beyond the dividers.) For example, the
following image shows a chair's red travel threshold that extends past a divider:
Drag the ExamTable so that it is a little further
away from the divider and none of the red travel thresholds extend beyond the divider.
Be aware that there will also not be any problems if the red travel thresholds are
exactly inside a divider.
Repeat the previous steps with all of the Exam Tables
to ensure their red travel threshold dots do not extend beyond each room's walls.
If you would like to turn off the visual guides for the A* Navigation system,
double-click the A* Navigator to open its properties
window. On the Visual tab, clear all the checkboxes.
Save, then reset and run the simulation model:
Now when you run the model, the patients and the RNs no longer walk through objects or
walls. Notice that the RN walks around the desks and the walls in the floor plan while
traveling to the patient vitals area with the patient.
Conclusion
Up to this point, you've created a simulation model of a health care clinic in which a
patient completes all the steps in their flow. In the next tutorial task, we'll look at how
to give staff tasks independent of a patient's flow. Continue on to
Tutorial Task 1.5 - Create
Independent Tasks.