Hey all, wanted to start a thread here to capture discussion surrounding updating our two spaces to allow for key-less entry. We’ll be building on the Authbox work that was done last year to authorize power to the laser cutter. That project has proven to be very stable and should be relatively easy to extend as the basis for an RFID based key-less entry system. I’ve already verified that the RFID reader we used in Authbox will work through the glass everywhere it needs to.
People who have been actively involved in discussions around this topic so far have been myself, Jenn Rand, @Elliot_Wells, and @Mark_Rosen. There are ostensibly four entrances that need to be worked out; two in Press Bay Alley and two in Press Bay Court. The problem boils down to designing or procuring actuation subsystems to unlock the respective doors, and then integrating them with a 5V control system (i.e. an light flavor of Authbox plus a 12 or 24 Volt relay).
We have a general constraint that the entrances should not alter (or at least continue to use) the Sargent lock mechanisms so that the buildings can still be consistently keyed by the landlord (@Elliot_Wells can correct me if I’ve mis-stated anything there).
Alley Exterior Door
Of all the entrances involved, we have the least liberty to alter this entrance since it is a shared entrance for the all occupants of the building. From the inside, there’s a crash bar. What we’re envisioning for the actuation here is something that, when 12V or 24VDC is applied will engage the push bar from the inside, and will naturally otherwise disengage (and not obstruct normal manual functioning of the entrance). One idea I’ve heard is some kind of strap harness that can be “pulled tight” by, e.g. a servo to depress the crash bar. I reckon something like this would do the trick in conjunction with one of these.
The other doors
We think these two might be able to be addressed in a similar manner to one another. Essentially we’d replace anything that looks like a rotary deadbolt mechanism with a self-locking mechanism that automatically locks whenever the door closes. Then we’d integrate electronics into the door frames with some kind of solenoid actuation mechanism that would perform a short-term ‘release’ sequence to briefly unlock the door. I’m fuzzy on the details of these ones, but I think @Mark_Rosen is investigating options here.
At the next Tuesday night meetup I expect to have one of those servo motors and one of those 12V relays to try out with the bench power supply and an Arduino.