03-31-2018, 11:54 AM
(03-31-2018, 10:04 AM)Canard Wrote: So, it’s triggered by anything moving toward it - even a pedestrian. I think the white square is a radar sensor, that detects motion toward (not away) from it. It only activated if you move toward it.
My guess? Since this is right at the end of the Willis Way platform, it’s a quick and easy way to get the NO TURN/TRAIN sign to come on when the train is actually moving toward it... not just when it’s sitting there, since it might be stationary, loading.
Seems weird in an era of positive train control to be relying on such an unintegrated method of triggering the light. Shouldn’t the computer simply turn it on when the LRV is approaching the intersection? I’m assuming the computer knows exactly where each LRV is and what it is doing. Or maybe use a track circuit, combined with knowledge of what the LRV is doing (direction of movement, or stopped). This would also mean that vehicles on the tracks would not trigger the turn signs.