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Products => Computers => Topic started by: karamba on May 12, 2020, 02:37:27 am

Title: Best single board for a lock.
Post by: karamba on May 12, 2020, 02:37:27 am
We have been using a FOB lock in a commercial setting, about 100 daily visitors, each has his own FOB key. In the same box with the lock controller is our own mini computer that runs windows and acts as an intelligent bridge between the controller and the main server that is located offsite. Now obviously this is too complex and expensive. We could retire the door controller and drive the locks directly from a single board computer that also would connect to he main server through https. The question is what board to use.  It is not a medical or airplane device but still needs to be reasonably reliable. More than one failure a year unacceptable. Would a compute module raspberry pi do ? If not what would ? Currently the bridge is a dotnet core application, so the board has to support linux.
Title: Re: Best single board for a lock.
Post by: fordem on August 05, 2020, 04:02:39 pm
From a reliability stand point, I don't see an issue with the Raspberry Pi - I ran a Raspberry Pi (3b) based ADS-B receiver for a number of years with the Pi mounted in a sealed enclosure and the only problem I experienced was a damaged PoE splitter caused by water leaking into the ethernet cable.  The splitter was not a part of the Pi and the Pi itself sustained no damage, I just lost the ability to communicate with it.

The Pi runs a debian linux based OS, so that aspect of the requirement is met, although I suspect you might need to recompile the app for it to run on an arb arm based processor.

You say you want to retire the lock controller and drive the locks directly from the SBC - I have the following questions ...

1 - how do you plan to drive the actual lock mechanism from the SBC?  Most SBCs have limited current sink/source capabilities and will need some sort of an interface card.
2 - how do you plan on interfacing the FOB to the SBC?  There are different types of FOBs and a reader of some sort is going to be required, which will also need to interface with the SBC.

I can see you replacing the mini computer you're using as a bridge now with an SBC but replacing the lock controller itself will present a few more challenges.
Title: Re: Best single board for a lock.
Post by: imk on August 17, 2021, 03:41:21 pm
What about an intel nuc i3 can run windows, so maybe run you old app.
I have couple running astronomy stuff/apps and seem pretty sturdy