question

Hey @Farah_najihah A, I'm not sure what you're asking with your first question about items clashing; do you just want space between the flowitems as they travel?

As for your second question, if you want to maintain a round robin operation for type 2 flowitems, you can assign a label (in my example I used "Lane" as my label) that will "Round Robin") the flowitems instead of using the "Send Item" event. This previous post inspired this solution for labeling. Essentially, you have the DP keep track of the "type2Count" and increment it each time you assign a Lane. You need to assign a different value for type 1 flowitems so when they pass over the DPs they don't throw exceptions.

if (item.Type == 2) {
int numOutput = current.outObjects.length;
current.labels.assert("type2Count", 0).value++;
item.Lane = ((current.type2Count-1)%numOutput)+1;
}
else {
item.Lane = 0;
}

For the DPs accepting the flowitems into different lanes, I used this conditional statement:

item.Lane == 1 && current.centerObjects[1].stats.state().value != 4

The first part is checking the Lane label on the flowitem. If it's is 1, send it down this lane (2 for the next lane, and so on).

The second part checks the state of the photo eye (PE) in the lane. If the PE is in the blocked state (4), then we don't want to send a flowitem down this lane. When a queue starts stacking up, it will eventually block this PE and not allow any boxes to go down that lane, thus not blocking the conveyor belt flow like before.

conveyor flow.fsm

Also, here's a smaller model to help see how it works: testing-code.fsm