The Dynamic World of Action Triggers

Arguably one of the most famous lines uttered by a movie character came to us through Clint Eastwood back in the early 70s.

In that famous scene, Dirty Harry (or police inspector Harry Callahan) has a suspect on the ground and is pointing a powerful 44 Magnum handgun at him. As the suspect lies there, you can see him contemplate reaching for his gun, prompting Inspector Callahan to ask, “Do you feel lucky, punk? Well, do ya?”

What does all this have to do with a driving simulator website, you might be asking. STISIM Drive has one little thing in common with Dirty Harry: a love of pulling triggers.

You won’t need to have a robbery suspect cornered to pull a trigger in STISIM Drive. In fact, we want you using our action triggers as much as possible! That’s how you can control the many dynamic events that our simulator provides. Vehicles, pedestrians, signal lights, animated objects, you name it, they all come to life when you set them up with a trigger that launches a new action.

Action triggers are easily the most powerful process that STISIM Drive provides. This is because they allow you to fine tune how the simulator and roadway objects will react to the driver.

A simple way to illustrate this is with a green light turning to yellow. Let’s say you want to trigger the light change so that the driver must decide whether to stop or try and make it through the intersection before the light changes. Because you can’t control the driver’s behavior, you need to set an action trigger that will change the signal light from green to yellow. Generally this is done with a headway time trigger, which says that when the driver is within a few seconds of the intersection, the lights will change. There are other ways to trigger the lights: distance, lateral position, speed, time, and more! You can also create complex action triggers that have multiple components, like position and time.

Mastering action triggers in STISIM Drive is pretty easy, too, because triggers only have a single parameter: the threshold that must be met for the trigger to fire.

In our signal light example, the trigger was headway time. The threshold was met when the driver got within a set number of seconds of the intersection. The art of using triggers is deciding which trigger will best meet your needs.

And once you’ve mastered action triggers, you control the roadway. STISIM Drive provides more than 30 different action triggers that allow you to control objects in the roadway environment. You can find a complete list of triggers and examples of how to use them in the SDL Basic Concepts Manual.

So now you have to ask yourself one little question: Do you feel lucky? Whether or not you feel lucky, feel free to pull all the triggers in STISIM Drive. You’ll be amazed at how those triggers will make things come to life!