Hi,

I am doing a project in school where particles will be moving like ants on the ground.

Here's one of my references: http://www.youtube.com/watch?v=lT2baaM4Tiw [youtube.com]

Here are my requirements:

1. make particles travel in a line with noise and ray it to the ground.
2. have some of the particles start and stop midway and after a certain time have them move forward again.
3. when particles collide, they would stop momentarily and then start walking again.


So far, I've managed to have the particles travel in a line with noise applied. I am now on the part where some particles, while in motion would stop (not at the same time ) and after a short pause would start walking again.

I've been trying for several days now experimenting with basic Source, Force, Collision, and Attractor nodes. 

So far the most success I had was setting the “scale” value of the force node to 0 based on time but it stops all existing moving particles. I only want some of the moving particles to stop. And the way it stops should not be a gradual stop as if the particles are on ice or water (Ants start and stop quickly).

The next was using a voppop, I had a simple multiplier with a constant (this will act like my switch for testing purposes). I can get the quickstop that I wanted but particles stop and never start again. I just want maybe 2 to 3 moving particles to stop and then after maybe 1 or 2 seconds to start again.

Any suggestions will be greatly appreciated. I've attached a simple dev test and my actual project.

Cheers,
Rod