Answers to Questions about the Bluetooth Passive Keyless Entry

Thanks for the constructive comments and questions. With this post I will try to address a couple of them.


The Android App:
The Android App is actually an android service running in the background that gets started at boot. THERE IS NO INTERACTION REQUIRED! The APP you see is simply to be able to exit the service and send some simple serial commands for auxiliary functions but you do not need to touch the phone ever to lock/unlock your car. THATS THE WHOLE POINT.

Security:
The car does NOT simply unlock when it is in bluetooth range. It establishes a secure connection to a phone that was previously paired with  a pin code. Additionally the bluetooth modem is only looking for MY particular MAC upon which it request a passkey. I would argue that 99.9% of the street criminals are not familiar with man in the middle attacks and do not carry around the equipment to pull this off. In fact most people who would be able to do this probably have a very well paid job.
Regardless I do see the concerns.

Battery Issues:
Since the Bluesmirf modem, which is powered by the vehicle, does look for my phone my phone will not use any more battery than usual when away from the car. Once you get close and the devices are connected the battery will drain but only until I Start my vehicle. When I start the vehicle the arduino will send the command to disconnect and actually turn of the Bluetooth modem. Once the ignition is off the BT modem is turned back on.
Q: "What Happens When you Phone dies?" - You should call a friend to bring your spare keys. Ohh wait...Kidding aside, this is a very good question and my thoughts are the following. Have an RFID tag on the back of your phone that is read through the windshield. Perhaps have a secret micro usb charging outlet somewhere on the car , but I feel this not very practical.
My solution was simpler: I have Tasker, which is a macro/automation program for android, simply shut down my phone when the batter level is at 4%. I would only restart my phone when I am back at the car or if I need to dial 911.

CatiaCarpentry and Criminals

After an unfortunate break in the Miami Metro Aera, I was looking for ways to make stealing things out of a locked vehicle a little harder. A quick Catia Sketch and couple of 3/4inch MDF boards later, I am happy with the result. While Ethan Hunt would probably be able to get in, it does keep my belongings out of sight for the ordinary street thug. While MDF is not the hardest wood, the box does have some metal bracing and is put together, perhaps making it not worth the effort for most criminals.

The Break In:

The Truck "Vault"

Catia Model and Final Install

An advanced "Arnold" Security system was proposed but could not be realized due to budget restrictions.

Refining the Keyless Entry Code

So as it turns out there is actually a way to properly read the RSSI (signal strenght) from the BT board. This is good news, since I now can actually use a proper signal strength indication to control the keyless entry system, rather than the pseudo-signal-strenght-package-loss-code that I had developed earlier. First tests showed the system works well but needs a little filtering and experimenting to find the right threshold value. Video of the results will be posted soon. 

Passive Keyless Entry System

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Analog Inputs and Debouncing

Whats all This about?

Time to apply that engineering school know-how to something useful. After a quick search through my junk pile and an online shopping spree it was decided relatively quickly that my truck is in desperate need of improvements.

After I got a little carried away using Adobe Premiere Pro this trailer was the result.

Sneak Peak: First attempts to communicate with my loyal companion:

The truck has enough electronics of all sorts to be experimented with and a after a brief moment of hesitation I quickly decided that my vehicle is in dire need of new features. Given that I knew my way around basic 12V car systems from several DIY repairs and Sound system installs I was eager to see what can be done with this unusual hybrid of expensive, thoroughly tested car electronics and an off the shelf $49.99, put together in the garage, arduino.

The Ideas of features that I want to implement are as follows in perceived levels of hardness (going from easy to WTF_BBQ...)

• Daytime Running Lights - run some leds only when the mainbeams are off
• HID protection - Protect my xenon lights from being turned/off to quickly
• Strobe Mode - Blinky Blinks... Make the car flash all sorts of colors and patters. Basically the Pin13 flasher program on steroids.
• Brake Light Suppression - Not Brake lights (this is for testing purposes only, don't try at home bla bla bla)
• Stealth Mode - Suppress ALL Exterior lighting with the push of a button. Perhaps turn on some IR leds and an NVcamera to still see where you are going.
• Pushbutton Start/Ignition System (perhaps even remotely!)- Make the arduino start and stop the engine. While this might seem simple this is safety critical so it gets bumped up some levels.
• Remote Control - control all the functions remotely with my Android phone
• Bluetooth - via a serial module
• SMS
• RFID/BT Anthitheft and Keyless Entry - If and Only If my phone is is within RFID range of the car unlock the doors and enable the starter. If phone gets out of range lock the doors.
• Communicate with the CAN BUS of the vehicle, Duplicate and HiJack onboard signals.