Can I walk past a motion sensitive light on Shabbat?
In order to respond this simple question we must first clarify a few Halakhic principles.
When one performs a permitted action and inevitably a forbidden action or melakha will result from it (this category is called pesik resheh) he is forbidden to proceed with the permitted action, even when he had not intent.
For example: dragging of a heavy chair over soft earth on Shabbat, will inevitably result in the production of furrows which constitute a melakha (activity forbidden on Shabbat, which in this case is Deoraita!).
When as a result of a permitted action ('walking') a forbidden melakha ('turning on the light') will be unintentionally and automatically generated, if I don't care or need the product that results from it, and it is not Deoraita, I'm allowed to perform the permitted action.
When I'm walking in the street, I don't need those lights (lo nicha leh), since the lights are shut off by themselves (not permanent, not Deoraita) so, I'm allowed to walk past that street even if the lights will be automatically activated.
Similarly, I'm allowed to walk by a surveillance system, even though little lights are turn on and off, or by a video cameras, as long as I don't do this intentionally or for my beenfit.
Passing by an optical eye which opens automatically a door I have to pass, iwould be forbidden because I care for that door to open, I need the door open.
NOTE: For those who want to understand better this Halakha I wrote a short explanation in the link below.
Candle lighting in NYC: 4:00 PM
Shabbat ends: 5:18 PM