Glen Akins Sure Knows How to Use His Head When It Comes to Access Control Projects

Glen Akins loves two things: biking, and hacking. So it's of little surprise to see him fusing the two together here in his latest hack, which looks set to make his life much, much easier!

If, like Akins, you have spent all day pounding the trails, throwing yourself and your trail bike down track after track, the last thing you want to do when you drag your bruised (and possibly broken) bones home, is to fumble around with a keypad, or worse yet, your keys, when you get home, ready to collapse.

I say worse yet in regard to keys, because one of the last things you want in your pockets when doing some serious off-road trail riding is a bunch of sharp, pointy bits of metal...

Akins thought that there must be an easier way to gain access to his garage after a long day, and set out to engineer a solution — using his head in a couple of ways!

Keep it under your lid...

If there's one thing you don't leave home without when going out on a bike ride, it's a helmet. Granted, keys, indeed, even a wallet might seem superfluous on a frantic downhill frenzy, but a helmet? Hell yes to that. We're hackers, not Jackass candidates!

If you want to keep the strength and impact rating of your helmet intact, you will be wise to not do a thing to alter it's physical design or structure.

But stickers? Hell yeah, Stickers are cool.

You know what's even cooler? RFIDstickers.

What's the RFI-Deal?

Having seen competitive bike racers timed using some pretty high-end RFID sticker tags, Akins concluded he could use a similar system to quickly and easily authenticate himself when he, in turn, granting access to his garage.

If you're not up to date on you reading about RFID, or if MIFARE looks like a mishmash of letters, you'd do well to read on through to Akins' blog — where he takes from zero to hero on all things related to common RFID access control systems.

Not only does he delve into the various types of cards and protocols available, but additionally, the security offered by each flavor of RFID, and further more, takes a good long look at the various types of RFID card and tag reader available.

Some of you may wonder why bother taking such a detailed look at the reader itself? Well, consider that in a well-designed access control system, the reader is going to be to sole point of attack for any skilled, nefarious actor.

You might want something more than an bare RFIDtransceiver IC on a breakout board guarding the gates to your kingdom...

Getting wise about the Wiegand Protocol

With a suitable radio technology chosen — a card in mind, and a reader selected, Akins takes a look at what's on the wires of these wireless card readers — and dives into the commonly found Wiegand protocol that a great many of them speak.

With an understanding of how the protocol works, both electrically and from an encoding standard, Akins is able to take this knowledge and pack it into a PIC18F45K50.

Below, we see this PIC proudly placed on a custom PCB, complete with all the peripheral parts to allow him to interact with the card reader.

We also see the required components needed to interface to the existing garage door opener.

It's simple, but effective!

In addition to the PIC, we can see two relay contact outputs.

Relay contacts are pretty handy when working with stuff like industrial automation controls — most of these are expecting a physically actuated set of contacts when it comes to inputs — which is exactly what a relay offers.

They are also great for simulating button presses on other systems, offering isolation from the other circuit if needed!

Two, illuminated push-button switches allow for some local user input, and with little other than the DC/DC regulator to provide the PIC with some power, all that is left to note are the Phoenix Contact compatible, heavy duty plug terminal sockets.

Extruded enclosures make things easier!

If you are looking to package up your project, and provide a bit of a more professional approach to your enclosure game, you should check out the many types of extruded aluminium enclosure that are commonly available.

With these enclosures being produced in large volumes, they offer a cheap, but sturdy way to box up our boards. However, I've seen many people favour plastic boxes, as they prefer the ease of machining that material when it comes to mounting buttons, etc.

Well, with the right approach, that doesn't have to be an issue!

These enclosures all offer standard endplates, with many a manufacturer listing the dimensioned drawing in a data sheet for that model, or even better, some now supply STEP files, good to go straight into your CAD program for editing.

With this data, you are free to model some replacements — I've used this before with 3D printing, and it looks very slick.

However, if you aren't able to get quick access to a 3D printer, or in the case where you want something a bit more robust — again, metal might be the way to go. So, with that need in mind, Akins turned to an online service — targeted at supplying exactly what is needed: Custom designed front panel pieces, in a range of styles to match your project.

With the service able to offer up so many options, Akins was easily able to spin up these two designs, with a perfect match to his existing enclosure.

Bringing it all together!

With a COTS enclosure, an appropriately sized and laid out board, and a little bit of farmed out front panel work, it's not long before this collection of parts transforms itself into a professionally finished project.

When you compare the final product, pictured below, to the 3D CAD renders previewed previously, there is more than a striking resemblance between the two.

We usually only see this level of render matching reality when we look at the designs that @PCBArts or @ketszim are turning out...

If it works, it works.

There's a slightly less polished looking dongle, dangling from the top of the photo below. All we can suggest is that given how slick the rest of the project looks — we'll let the taped up door transmitter pass.

If you are looking to implement any sort of RFID access control, we've got to recommend that you go and get a look at the write-up over on Akins' personal site — there's a lot more detail that we don't have anywhere near enough the time to cover here!

And, as always, here's a GitHub link for the intrepid to get going with!

Follow @bikerglen on Twitter for a good mixture of retro hardware hacking, and some crazy mountain bike trails!