I have a hidden staging yard with three routes. Each is divided in the middle, consisting of two storage blocks each. All trains enter from the right and exit from the left end. I want to automate trains running into storage, with the first train stopping at the end of the left block, and if the left block is occupied, the second train stopping at the end of the right block until the left block is cleared.
I have block occupancy set up on BDL168s and all works well with trains displayed on JMRI. This requires visual observation to control where trains stop.
I'm thinking of using IR detectors across the departure end of each staging block, and somehow feeding the signal to JMRI via the inputs of a DS64 which are not involved in the turnout functions of the DS64.
Does anyone have access to a circuit to make this connection? Advice on what brand/model of IR detector to use? Caveats on why this isn't a good way to stop the trains in the right place?