Car DVR replacement and related shenanigans - part 2

Moving along with more details, like I mentioned in the previous post, the rear camera was reused from the previous installation. This CCD based camera happens to be superior to the basic CMOS camera bundled with the kit. Both in terms of the quality of the sensor itself and its low light sensitivity, but also regarding the lens, featuring a wider viewing angle (important given its role as a backup camera).

The only change however was a substantial improvement in the mounting design, by having added an U-shaped plate in the rear of the camera, with a 4-screw mount instead of the original 2 screws attached to the sides of the camera. This provides a more solid attachment to the L-shaped aluminium parts that in turn stick to the door through an adhesive:

Car DVR replacement and related shenanigans

Introduction

With the vulgarisation of miniature cameras and computing devices of all sorts, technologies that fundamentally serve the mobile industry become cheap enough and available to the point of being useful for other purposes. That is the case of DVR devices for automotive use.

Carjacking - shortening the path for justice

As automobiles become more sophisticated, direct theft by tampering with the ignition system becomes a nearly impossible task. This narrows down the choices left for the criminals, who end up adopting the only choice where successful access to the vehicle is guaranteed: threatening the occupant(s) with a weapon in exchange for the car.

In general the criminals can get away with this type of crime if they are efficient and careful, leaving the victim with few evidence to help in the investigation and tracking of the vehicle.

However, once again we can put technology on our side, and in an attempt to be resourceful enough, take advantage of two broadly available devices: a cell phone and a GPS module. These devices
are becoming cheap enough to have dedicated in a discrete location inside the car for a single purpose: on demand location.

By being able to query the location of the car just by sending an SMS message to it and get a reply with the corresponding GPS coordinates, this could be a useful tool in the police work, as real time location would always be possible.

Following this idea, I've decided to attempt a simple implementation of one such system which I have designated "Vechicle Finder". Having as a platform a Nokia smartphone and a Bluetooth GPS device (both sitting on a board for convenient fixation of the apparatus), I have developed a Java application which reads the GPS coordinates and sends it as an SMS to the originator of the request SMS:



Upon receiving an SMS containing a special command and some optional parameters, this onboard device will reply with another SMS containing the following data: