Trying to add steering behavior to avoid collision

Development Programming & Scripting AI
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Hi everybody,
I’m trying to add a repulsive force to avoid collision between my AI agents. I have a static mesh in front of my AI character that computes the overlap with another character. If there is overlap, I change a variable in the controller to let it know about the overlaping, to make the calculations. Inside of a function in the controller, I’m making a test calculation to see if something happens, but I can’t change the velocity of the characater to apply this force.
I was searching how to change the velocity of the character using the computed force, but I didn’t find how to modify the velocity of the character.
Inside of CharacterMovementComponent I found that you can apply a force or an impulse, but as I’m trying to do it in the controller, when I get The Pawn I can’t not apply this force or impulse. I made a Cast of the pawn movement component to a character movement component and then I can access to the functions, but anything happens…

Actually I don’t know if I’m focusing the solution in the wright direction… Is the first time I work with Unreal Engine and I’m a little bit lost about how to work with it.

Thank you very much!

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Hi dzeligman,

I know that Unreal has its own avoidance system, but I’m making a project in university where I have to achieve collision avoidance with Unreal 4… This is why I’m trying to do the steering behavior… I have done one very rough hardcoding the values, but now I have to program another a little bit more complex…

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I’d recommend using the built in solutions instead of rolling your own. Unreal has two built in solutions for avoidance. The first uses the AvoidanceManager and is a simple RVO avoidance based algorithm. The second is a partial port of Detour crowd. More info available here

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Just to let someone know if is searching something related with my doubt.
I used the function MovementComponent::MoveUpdatedComponent(FVector Delta, FRotator NewRotation, bool Sweep) inside the Controller of the AI character to give it a delta velocity that I calculate in order to avoid the agents I detect it has in front.

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Archive of detour tutorial.