user-1: I am working on a bike protection project that is supposed to be part of my CS syllabus. Although I got most of the things worked out, there is one thing that bugs me; that is to how to stop a moving bike using an Arduino built into the bike, possibly from a remote system, like another Arduino or Android app.
Is it possible to do it using an Arduino and some other modules maybe?

user21015: Assuming that you simply want to stop the engine, Gerben's comment has the answer: Put a relay in series with the ignition. Control the relay with the Arduino. 
Opening the relay breaks the circuit. Ignition is now off, and the engine will no longer run.
Of course, the bike can still roll without engine power. If you want to completely immobilize the bike, you need to engage the brakes, or lock the wheels in some other way. And that takes a whole lot more hardware.

-1: <p>I am working on a bike protection project that is supposed to be part of my CS syllabus. Although I got most of the things worked out, there is one thing that bugs me; that is to how to stop a moving bike using an Arduino built into the bike, possibly from a remote system, like another Arduino or Android app.</p>

<p>Is it possible to do it using an Arduino and some other modules maybe?</p>
 21015: <p>Assuming that you simply want to stop the engine, Gerben's comment has the answer: Put a relay in series with the ignition. Control the relay with the Arduino. </p>

<p>Opening the relay breaks the circuit. Ignition is now off, and the engine will no longer run.</p>

<p>Of course, the bike can still roll without engine power. If you want to completely immobilize the bike, you need to engage the brakes, or lock the wheels in some other way. And that takes a whole lot more hardware.</p>
