DIY vehicle tracking/logging, theft detection, and vehicle health reports

pidzero

Greetings forum,

I have a (probably not unusual) idea for a discrete "car-puter"; that is, a headless (read as "unobvious, hidden") microcontroller/microcomputer, enabled with GPS, CDMA, and Bluetooth. The CDMA radio would "phone-home" (TCP, that is) with GPS information, and On-Board Diagnostics (retrieved via Bluetooth OBD dongle). Some other features would be:

* Continuous power. While vehicle is ON, it's running in "full-power mode" and charging backup batteries. While vehicle is OFF, it is running in a "low-power mode," and using the backup battery power... Therefore as to not drain the car's 12V starting battery.

* Safe operation in high cabin temperatures (no backup battery explosion due to HOT vehicle parked in the summer sun). (Fire-proof enclosure, capable of containing a fire or explosion?)

* Accelerometer and/or other such sensor for notification/alert of unexpected movement, or glass-breaking (a collision into my parked vehicle, or theft of vehicle or its contents)

* future additions (unobvious button and LED status light in front of cabin, perhaps)

* keychain fob remote? existing vehicle key fob lock/unlock detection to arm/disarm?

Does this idea tickle anyone else's fancy? Do you have ideas?

pidzero

msrobots

Lets start with power. The propeller can get to very low power consumption when running in RCslow with one COG active. So my guess is that a propeller will not drain a car battery even if running for weeks. But the electrical system of a car is quite noisy, not easy to get smooth 6 volts out of it to power a (switching?) regulator. As long as the car is not running everything is easy, but when running you have a lot of spikes and noise on the power lines.

Sadly in RCslow or RCfast serial communication does not work without tweaking of the software for each Propeller chip and 'normal' temperature.

But you still can test for glass breaking and door opening while in low power mode. Once in a while you might switch to operating (crystal) frequency and power up your GPS to get a current location. But be aware that GPS values are constantly wandering around even if stationary. So you will need a quite big 'dead band' to avoid unneeded alarms.

By power up I mean that the running Propeller needs to switch power on and off for some devices like GPS.

I would not just use accelerometer but one of them units used on the quad-copters. They combine accelerometer, compass and other sensors to calculate the position of the quad-copter. First you have more information at hand, like angles of the car changing (as in getting towed on a tow truck) and second there is code there in the OBEX to use them. There are different sensors in use but mostly SPI and I2C, so they would possible work with RCslow/RCfast.

The copter try to get a new reading at 50 or more times per second, but for your car every minute would work. So no need for speed.

I guess the compass function will not really work inside a car, to much metal and wires around.

I do not know much about Bluetooth but I think it might not be easy to read a OBD dongle from the propeller via Bluetooth on the propeller. But there is hope in the OBEX again. Somebody wrote some objects to use 2 chips and hardwire OBD port to them and the propeller.

My cars predate OBD so I never build or tested it, but it is there.

If your car is newer you might have some build in screen already for navigation/entertainment system. These usually have unused inputs usable from a propeller for video output (TV/composite/VGA, either or).

If your CDMA module can receive messages, you could switch off the ignition via TCP/IP. I personally would not automate this, should be on until I press the button. Can hit yourself hard if not working correctly.

when the car is running, the Propeller can run full speed no need to save power, so maybe logging of GPS data to SD card?

Enjoy!

Mike

homosapien

I was going down this same route about a year ago, when I realized that a cheap Android phone with my custom app fit the bill better than any uP with peripherals ever would - I bought a bunch of ZTE Zingers for $9 each when Bust Buy was dumping them. I wish I had bought 100 rather than just 5.

The real issue is getting connected without spending a lot of $. Some of my devices are very low usage, so I can do a plan that costs $3 month. If you need accurate GPS, you need data, and the best I have found for that is $30 month.

Nate

Chris Savage

I have a current GSM-based vehicle tracker that I built around a BS2p24 years ago. It has a Sprint SIM with unlimited TXT messages for $10/month. I was going to revise it, however my app makes use of the Google Earth API which is now being deprecated.

Thinking about just re-writing the app (VB.NET) to use a browser window and pass the coordinates via the URL (Google Maps).

kwinn

homosapien wrote: »

I was going down this same route about a year ago, when I realized that a cheap Android phone with my custom app fit the bill better than any uP with peripherals ever would - I bought a bunch of ZTE Zingers for $9 each when Bust Buy was dumping them. I wish I had bought 100 rather than just 5.

The real issue is getting connected without spending a lot of $. Some of my devices are very low usage, so I can do a plan that costs $3 month. If you need accurate GPS, you need data, and the best I have found for that is $30 month.

Nate

That's a good approach if you can get phones at that price. Might even be worth adding a 300 - 1200 baud modem to avoid having to get a data plan. Of course a propeller can be used as the modem as long as it could be interfaced to the phone to dial and send the tones. Bluetooth perhaps?

RS_Jim

kwinn wrote: »

homosapien wrote: »

The real issue is getting connected without spending a lot of $. Some of my devices are very low usage, so I can do a plan that costs $3 month. If you need accurate GPS, you need data, and the best I have found for that is $30 month.

Nate

That's a good approach if you can get phones at that price. Might even be worth adding a 300 - 1200 baud modem to avoid having to get a data plan. Of course a propeller can be used as the modem as long as it could be interfaced to the phone to dial and send the tones. Bluetooth perhaps?

Won't the phones connect via wi-fi even they don't have a plan. I have 2 old android devices that I can still run data apps on with wi-Fi. I will check them out for gps when I get a chance.
Jim

kwinn

RS_Jim wrote: »

kwinn wrote: »

homosapien wrote: »

The real issue is getting connected without spending a lot of $. Some of my devices are very low usage, so I can do a plan that costs $3 month. If you need accurate GPS, you need data, and the best I have found for that is $30 month.

Nate

That's a good approach if you can get phones at that price. Might even be worth adding a 300 - 1200 baud modem to avoid having to get a data plan. Of course a propeller can be used as the modem as long as it could be interfaced to the phone to dial and send the tones. Bluetooth perhaps?

Won't the phones connect via wi-fi even they don't have a plan. I have 2 old android devices that I can still run data apps on with wi-Fi. I will check them out for gps when I get a chance.
Jim

Sure, they can connect to Wi-Fi, but you have to have a plan for that or a hot spot you can connect to. AFAIK there is no Wi-Fi equivalent to purchasing a number of minutes of talk time, which is the lowest cost plan I am aware of.