How can we create a explosion force?

with ForceMode.impulse or
rigidbody.AddExplosionForce?
It should push objects away just for a moment just like normal explosions, not a constant force "shield"

 

You might be calling your addexplosionforce every frame. Try only calling it once, such as when an event happens.

For example, only call it when you click your mouse.

 

thank you, i'll try

 

here is a video unity made just for explosions https://unity3d.com/learn/tutorials/modules/beginner/live-training-archive/fun-with-explosions
I believe they only apply the force OnMouseDown