Arduino Entry system using 12VAC doorbell trafo

[luria]

Hi! Enticed by an interst for home automation and electronics (of which I have limited experience) I recently started a small project. I own a house and rent out the second floor. The tenants and my family share a common entrance door, requiring a lot of keys. Reading about the arduino I started to think about a keyless entrysystem and the possibility of providing a upgraded doorbell and VFD status display at the front door. I also want to incorporate magnetic switches to monitor door status for all three doors (basement, our entrance door and the front door shared with the tenants).

Luckily my house is equipped with an ancient doorbell transformator, deliviering approximately 12 volt ac through surface mounted wiring to two old doorbells. Powering the arduino with this powersource should make for a clean setup without wallwarts, and also be able to provide power for a magnetic doorlock. The rough sketch of what I want to accomplish is as follows: A nice, clean aluminium plaque at the front door, providing bell buttons for my family, a separate button for my kids and one for the tenants. I chopped a old htpc case (Antec Mozart) for a nice 16x2 VFD display and the aluminium plaque with a display window. VFD is a necessity here, outdoor temperatures commonly drop to -25 degrees C (or colder), so no LCD would reliably work here. The VFD also has bright blue characters, perfect for those dark, gloomy winter nights.

I have purchased a few magnetic door contacts (http://www.clasohlson.no/Product/Produc ... d=55369098). A little experimenting with kaku magnetic door sensors left me disappointed. I do not want to surface mount ugly, expensive sensors and accept the lessened reliability of radio communication and battery changes, so i drilled a couple of holes in the doorframes in order to install these switches. They are practically invisible and work 100 % reliably. These will be wired to the arduino using a resistor ladder, thereby only requiring 1 pin and also giving me the possibility of monitoring a broken or cut wire.

In addition i have bought a pressure sensitive mat (http://www.clasohlson.no/Product/Produc ... =152538724), this will for now reside under the doormat at my familys entrance door, but later i will put it under my new wooden floor when i redo the hallway. This should provide the arduino with enough information to reliably estimate if someone is leaving or coming (door opens/pressure detected vs pressure detected/door opens), and display appropriate information on the VFD (house armed/disarmed, doors/widows open, turn on lights etc).

Today i ordered a simple RFID reader (TTL) and an antennae that should fit behind the plaque perfectly. Still on the buying list is a magnetic door lock for the front door.

My plan is to pull wiring from the front door and the sensors to a indoor arduino with a LCD display. i will run 12v to the front door and to the arduino situated next to our entrancedoor, and a network cable containing leads for the VFD, doorbells and sensors beetween the two doors. I should be able to see status of all doors, keep a small log of doorbell and door activity, and open the door with a switch. I have purchased a arduino network shield in order to forward all this information to my domotiga server (and possibly be able to open front door with sms or a web interface for kids, carpenters and my wife who forgets easily but is not easily forgotten)

Being a big project for me, I have started out with a simple doorbell. My arduino is now powered through the 12v ac using a home made circuit with a diode bridge, a couple of capacitators and a 5v voltage regulating IC. The exisiting doorbell wiring is hooked up to a optocoupler trough a diode bridge, capacitors and a resistor. When my doorbell is pushed, my arduino plays the Mario theme to the amusement of my kids (always entertain the masses if u need massive support). A SAE 800 tone generator was tried, but it's reassuring "ding-dang-dong" did not receive support, so we're sticking with mario.

Currently im hacking away in order to get the aluminium panel ready and all buttons installed. Using a small motion detector (https://www.elfa.se/elfa3~eu_en/elfa/init.do?toc=20135) to turn on/off the outdoor vfd (and log more data) is an option, but that will be put on hold for now. Hopefully I'll locate my camera one of these days and take some pictures and eventually provide you with schematics and code.

[Mdamen]

Interesting reading material!
Nice to see what people do with Arduino's. And the amount of customization you've put into this project already.
Looking forward to see the pictures. Did you consider using simple reed switches instead of those KAKU magnetic door contacts? (Those are horrible indeed) or did you just "abuse" the existing KAKU switches for that?

I will put this project on the projects list, good luck with the further progression of the project and please keep us informed!

[luria]

I bought simple reed switches intended for wired alarmsystems (see link in post). These are installed by drilling a 9.5 mm hole in the doorframe (switch) and door (magnet). Very clean and nice indeed. i'm doing a renovation of the house, so access and hiding wiring was easy. The kaku switches are on display in the fast growing basemenet home automation museum.

[steffex]

Just a little reminder, because I can't determine how you want to log:

Keep in mind that logging on the Arduino itself is no problem when you use the internal memory of the arduino (using: http://arduino.cc/en/Reference/EEPROM). Don't save the settings in a variable inside the arduino sketch, because when the arduino loses power and therefore resets, you lose your logging.

But I like your project, I'm also looking into this type of sensors to detect if I have windows open or not.

[luria]

I got a ethernet shield, logs will therefore be sent to the domotiga server.

Adding pics of the resistor ladder (there will be two) using 80k, 40k 20k and 10k resistors and a 100k voltage divider

Resistor ladder

res_ladder.jpg (71.44 KiB) Viewed 18562 times

This gives me different readings on the 0 analog pin according to different key combinations.

Here is pics of the reed switch installed (painting not yet finished, some glue residue around switch)

reed_sw.jpg (55 KiB) Viewed 18562 times

... and of the magnet installed in another doorblade (the old kaku 606 visible behind)

reed_magnet.jpg (58.78 KiB) Viewed 18562 times

Finally the old doorbells

door_bells.jpg (57.32 KiB) Viewed 18562 times

Thats it for now. RFID antennae arrived, still waiting for other parts

[luria]

RFID Module, powersupply and antennae has arrived. I bought a Leser 1 plus from Codatex, plus power supply and a large antennae. Hooking everything up and running a small test outputs the transponder ID to VFD. As you can see, i 'm using the LCD3wire library and a 4094 set shifter IC in order to save pins. In addition, i found the newsoftserial library, which is using interrupts in order to read the TTL input - e.g. program won't stall waiting for input.

rfid_added.jpg (188.76 KiB) Viewed 18541 times

[luria]

Finally done with the "mechanics". The aluminium sign has been sanded, sanded, sanded and sanded. It took ages to get rid of the black oxidation, company label and get a nice surface, hence no updates in a while. Drilled holes for and mounted the three buttons and prepped and mounted the 2.54mm experiment board on the backside. Next up is the electronics and display. Wife factor is reportedly adequate.

new_bells_to_the_wall.jpg (189.67 KiB) Viewed 18510 times

Fitting the electronics will be a challenge, but the elevated mount means that I can use a "sandwich" construction if I run out of space.

Beyond_the_bells.jpg (151.15 KiB) Viewed 18510 times

Another shot of the front:

bells_in_your_face.jpg (125.75 KiB) Viewed 18510 times

Thats it for now. New pics when I have made some progress.

[Edwin2008]

looking pretty good.
In my old house i used the same magnetic stuff but a collegue attended me on the fact that it is possible to detect the magnet from outside and than use a strong magnet to disable the switch while forcing an entry. He solved is by mounting microswitche in the door post (hing side) in the hole where the pins comes that prevent lifting the door ("dievenklauw").

[Digit]

Looking good! Always nice to see projects grow from breadboard to the real thing!

[luria]

The magnet switches is mostly just to detect open doors and prescence, I'm not planning on using this as an alarm. However, the microswitch is a good idea. I have one laying around, gonna figure out how I can enhance security a bit later.

[Edwin2008]

The best time to do this kind of work is when your building the house, i'm afraid i'm past that point so i have to rely on magnetic together with infrared

[luria]

Moving forward. I got a few hours male-time tonight, most of the breadboardstuff is transfered to the experimentboard. Getting late, making the final connections tomorrow.

electro_cute.jpg (182.69 KiB) Viewed 18490 times

Some may notice the green connectors- Yes, I ordered the wrong ones. However, they are perfectly useable. This has ended up as several layers, since i want to be able to quickly pull it apart and/or modify it. It could have been done quite nicely if I was willing to solder everyting in place.

electro_cuter.jpg (149.31 KiB) Viewed 18490 times

On a small sidenote, the build quality and attention to detail on the codatex rfid + powersupply is very good.

[luria]

weekend update!
As you remember, I was able to finish off the doorbell and most of it's connections last weekend. This weekend I was able test the doorbell assembly and do some modifiactions to the software.
The RFID reader, doorbell and reed switch readings and the VFD is working. The doorbell assembly will be mopunted by the outer door and connected to the arduino with UTP network cable. The RFID unit has a powersupply which can transfom the 12/8 VAC fro, the doorbell trafo to a regulated 5VDC, thereby powering the arduino via the utp-cable. The arduino will be placed in the basement, and i plan to use another utp cable from the basement to the inner door and display some info on a LCD, (and also read the status of the reed switches at the inner door and basement door). I might use three buttons next to the inner door LCD in order to make a small menu system, enabling some local WAF friendly control.

I have already got the second 4 line LCD display going. Some modifications to the original LCD3wire lbrary was necessary. Now I can display different messages at the front door and at the inner door.

Todo list:
1) Get an electric door strike for the front door. Offers welcome.

2) Make a hole by the front door and mnount the doorbell assembly.

2) Make a housing for the inner door LCD and possibly some buttons.

3) Connecting the arduino to my Domotiga server via the ethernet shield.

dual_lcd.jpg (180.26 KiB) Viewed 18464 times

door_dual_lcd.jpg (200.06 KiB) Viewed 18464 times

door_dual_lcd_closeup.jpg (162.83 KiB) Viewed 18464 times

[luria]

Finshed the electronics on the breadboard. I now have all components working. In addition to the LCD wiring, you also see the SAE800 IC hooked up - this makes the "ding, dang, dong" noise and will be the adult bell -The arduino will play the Supermario theme song for the kids.

all_hooked_up.jpg (229.74 KiB) Viewed 18439 times

The amount of wiring is staggering. I'm running 8 connections to the front door and 8 connections to the inner door. Trying to hook all this up to the arduino made me build a homemade prototype shield. In addition to all the connections, it also houses the SAE 800 IC, thereby saving a wire to the inner door. Mario theme song and two doorbell sounds require three pins - two to the SAE chip and one for the theme song. Doing it this way I only need two wires for the inner door speaker.

The connectorshield goes on top of the ethernet shield, which in turn is soldered to an arduino pro board in the bottom.

layered_cake_of_incompetence.jpg (191.71 KiB) Viewed 18439 times

incompetent_layer.jpg (144.11 KiB) Viewed 18439 times

Next is soldering up the lcd and the resistor ladder for buttons, security mat and door sensors at the basement and inner door. A small aluminium housing for this is on order and will arrive shortly.

[Edwin2008]

looking good!