Hot answers tagged automation
To get the actual time of day, you can use the mindsensors.com Realtime Clock Sensor.
I think I'd use the ultrasound sensor instead of the touch sensor (or the brightness sensor with the light turned on in a dark tunnel). I haven't tried this but I'd worry about the touch sensor derailing or scratching the train. Otherwse, your system sounds pretty doable. The collision risk could be addressed by setting up the sensor a little further before ...
Time is thought of as a sensor value, measured in seconds. The Timer sensor can be used directly, as part of a Wait For block, as part of a Loop block.
Lego NXT vacuum cleaner project included charging station http://www.plastibots.com/index.php/2010/11/13/pulito-featuring-dflex/
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