Cryptic car stereo

Community Projects
1

Hi all!

This is my first post. Before I begin, here are two important things: 1) I’m an electrical engineer and currently employed as an embedded software engineer for a really cool SDR company in Boulder, CO; 2) I’m not an audiophile and the audio quality in my vehicle really isn’t important to me and only recently hit my radar for specific reasons.

So, I have a 2007 Wrangler X (base model–no frills, crappiest radio and speakers imaginable… I mean, it’s got a hands-free phone button that actually does nothing). Since I have an after-market soft top and often drive with it off or the windows down, the audio just doesn’t cut it and I can’t stand it anymore. I mean, it’s offensively bad. :drool:

So, after looking around, I think I want to tackle building my own stereo from scratch. Here are my ideas so far:

  1. I’m pretty much settled on a PI since I do need audio processing (and possible a lot more processing…)

  2. I don’t want a CD player; all I want is Bluetooth streaming (hands-free calling would be nice, but not required), a USB port for thumb drives containing audio (or crypto stuff) and an FM receiver (while not a your stereotypical listener, I can’t live without live-broadcast public radio)

  3. Since I’ve settled on a real computer with a good bit of processing power and also drive the most theft-prone car ever made, I’d like to build in some security measures. I’m thinking perhaps some mix of RFID, bluetooth (???), ISM, biometrics… who knows. Sparkfun has lots of cool stuff I could stick up in there.

  4. GPS/IMU/location services

  5. With regard to 3, sensors on anything I care about (doors, glove boxes, anything I might want to tag)

  6. Comms! Obviously GSM comes to mind first, but I’m getting ready to become a licensed Ham (though I don’t know what options I’d have there), the ISM SDRs my company builds, ZigBee (XBee? I’m not up on that stuff), again… who knows

  7. ODBII access

  8. Silent alarms: with regard to 3, 4, 5, 6 and 7. I can set up rules to send encrypted telemetry to one or more servers I have as well as text messages to cell phone(s) if the computer decides something bad has happened; or I can turn on automatic telemetry! It might be cool.

Back to the car stereo stuff… I obviously know I’d need an external amplifier and have no experience with audio handling or bluetooth for that matter. For an HMI, the less user friendly and cryptic, the better. I’m fine with a couple LCD panels and a few buttons. Hell, hex entry would be fine; or context-sensitive blank buttons that light up when pressed. The less attractive to thieves, the better. And of course, I’d have it start screaming telemetry if it detects it’s being tampered with.

So, has anybody tried anything like this? I figure if I grab a PI, a BT adapter (if it’s not built in) and an LCD or two, I could get going prototyping.

Peace out and don’t fear the reaper!

Tom

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Two things:

  1. If you want to build this for fun, go for it and have a blast.

  2. Thieves will steal anything they think they can sell. I’ve had my car broken into to for a stereo that looked like crap and cost less than $20. If someone is stealing your car/stereo/belongings, by the time you get an SMS or whatever telemetry, it will be long gone. Better off seeing if your insurance company will give you a discount for one of the Lo-Jack clones (no, they won’t discount for a DIY clone).

tl;dr: do it for fun, don’t expect any theft-decreasing benefit from it.