PIR False triggering

[John Wohlers]

I have two of the PIR sensors and have mounted them inside PVC.  Indoors, when testing them they worked flawlessly.  Once I took them outside to test them, even with 40 seconds of warm up time, they constantly trip until after the sun passed below the line of houses across from my house.   Are the parallax sensors incapable of being used during daylight hours when outdoors?

[JonnyMac]

I don't think you'll find any PIR that will work in sunlight -- there is just too much IR in its spectrum.  Perhaps the field-of-view of your PIR contained a reflective element that bounced a lot of IR into the sensor.  PIRs are not my favorite, and I would only ever use them in highly protected areas.

[John Wohlers]

I don't think you'll find any PIR that will work in sunlight -- there is just too much IR in its spectrum.  Perhaps the field-of-view of your PIR contained a reflective element that bounced a lot of IR into the sensor.  PIRs are not my favorite, and I would only ever use them in highly protected areas.

That was pretty much what I figured was going on. 
I built all of my props with the ability to easily swap out the PIR's for floor mat switches.  I have been making mine from hacked Dance Dance Revolution Mats.  The floor mats work perfectly all day and night.  I just lay them on the sidewalk, cover them with tar paper and duct tape that to the sidewalk, it works well, is durable, and still provides great traction.  For added camo we tend to cover them in leaves.  The Prop-1 reads the modified DDR mat just fine and I have yet to have any false triggers.  Next year I think I will have to add a few more mats though as to make sure things are triggered when people approach from either direction. 

What other outdoor friendly sensor types do you suggest?

[JonnyMac]

You might check an industrial alarm catalog.  Those companies tend to make sensors that can stand up the rough environments -- but cost might be tricky.  Sounds like your home-brew mat switch is a good solution.