Note: All picture
labels are located at the bottom of the picture or diagram
to which they refer.
Our project will consist
of an RFID reader which will read in numbers from cards
similiar to those used by students and staff to enter
the Seaman Center. The RFID reader will send the card
number scanned to a server via USB port. The server will
search a database to see if that card is authorized to
open the door, and if it finds that the user is authorized,
it will send a signal to the lock to open it.
We also plan to include
an online website on the server that will allow the customer
to open the door remotely. The applications for this include
the ability for a customer to open their front door while
at work so a repair man could enter, allowing a child
into the house after school, and so on and so forth.
Schematic 1 shows a basic
outline of the system we plan to build.
-RFID Card Reader Serial
-Boarduino (all parts listed): $25.00
-Fail Safe Electric Door Strike: $38.96
The RFID reader
we will be using is produced by Parallax Inc. Click HERE
for the reader's data sheet. The Parallax RFID reader
is low cost capable of reading passive RFID trasponder
tags from up to 1&3/4 to 3 inches away. The RFID reader
requires 5V of DC supply, has a bi-color LED to identify
activity taking place. The RFID reader includes four pins
to connect to power, ground, and the access control microprocessor,
which are labeled in the legend below.
Parallax RFID Reader
Parallax RFID Reader
The final architecture
of our lock-access control microprocessor-RFID is still
undecided, but we have gotten the Parallax RFID reader
working with a Boarduino USB solderless breadboard. The
Boarduino is a copy of an Arduino Board--it comes with
a chip pre-programmed with the Arduino bootloaderwith--a
few noteable differences are:
* Shields cannot be used
as the form factor is so different
* There are two versions, a DC version and a USB version
* For the DC version there isn't an on-board USB chip.
This means you need to use a USB-TTL cable or a MiniUSB
(or any other FTDI breakout board) which is not included.
There are also no rx/tx LEDs and no rx/tx 1K series resistors.
* For the USB version, there is an on-board USB chip but
there isn't a DC jack or 5V regulator, you can power it
through the USB jack. There is a rx 1K resistor so you
can use this to talk to serial accessories.
* 16.00 MHz ceramic resonator is used instead of crystal,
so cycle speed may be off by +- 0.3nS (0.5%). This isn't
relevant for UART timing, servo drivers, PWM, etc. but
could be an issue if you need nanosecond-precision timing.
Note that the Arduino software only provides millisecond-precision
timing for general sketches (1 second = 1000ms. 1ms =
The Boarduino we've selected
to use is powered and sends data to a PC via a USB cord.
The USB Boarduino has the following specifications:
The specifics for the
USB boarduino include:
* Designed to plug into a breadboard for easy prototyping
* Petite size, only 2.75 " x 0.8" (75mm x 20mm)
* All 'standard' pins are brought out - Digital 0 thru
13, Analog 0 thru 5, ARef, 5V, Ground, 3.3V and Reset
* 2 LEDs, green power and red "pin 13" LED just
like the Arduino Diecimila
* Standard Reset button
* ATmega168, running at 16.00 MHz, just like the NG and
* 6-pin standard ICSP header
* Standard USB jack
* USB or external power, selectable with a jumper
* 500mA fuse protects your computer from current overdraw
* Auto-reset capability
* Available as a low cost kit with standard parts, so
its never out of stock
* All through-hole parts are easy to solder - SMT chip
is presoldered & tested when purchased as a kit
Here is a picture of
the USB Boarduino, fully assembled.
official Arduino board
website is located at www.arduino.cc/.
The parts sheet for the
USB Boarduino is located at www.ladyada.net/make/boarduino/usb-parts.html.
Electric Door Strike
emains locked during
-2,500 lb Forcing Strength
-Driven by 12V relay
The door will remain
locked during power outages, preventing a security breech
should the power shut off.
for the door strike is located at www.asihome.com
-Relay driven by ATMega168
pin (~25 mA)
-500Ω Coil Resistance
-5V/500Ω = 10 mA < 25 mA
The website will
allow remote users to log in online and remotely unlock
the door. The website will include the following parameters.
Windows Server 2003
-MSSQL Server Database Backend
-Connected to Access Controller via RS-232
-Dynamic DNS Client
-Located in close physical proximity to door being controlled
This part of the
project has a great deal of expansion potential. A camera
could be added to provide a video feed or snap pictures
every few seconds and provide identification of the person
being allowed through the door being opened remotely.
Opening the door via iPhone or BlackBerry is also an area
into which future research could be done. There is also
potential to make money off monthly subscriptions for
the use of this service for homeowners, or to make money
in the set-up and up-keep of such systems for corporate