As I embark on my first serious project on Arduino, greatly appreciate your help on my question.
I would like to find out how I can detect if my project is moving at any instance and if so the direction of the motion. As an example, I want to detect if a car is moving from inside the car without any access to outside of the car's interior (say, the wheels or view of static objects on the street through the window) to use it as a reference.
There are numerous questions on this topic in this and other forums. After going through as many of them as I could find, it seems to me there are few prevalent solutions:
1) Use an accelerometer and use general laws of dynamics to detect if there is any distance traversed from the acceleration detected. For example, see this: http://forum.arduino.cc/index.php?topic=256184.0.
2) Use a spring-in-tube vibration sensor (such as this: http://www.beelee-switch.com/prodcuts/Tact-Switches/prodcuts/vibratio/051292012.html). However, it is not clear to me if it detects simply vibration as opposed to a motion (with a linear or non-linear direction).
My question is: have you actually used any of them (or something else) and got results similar to what I am describing? I am only interested about practical answers that worked for you, not theoretical discourses.
Thanks again in advance for your valuable direction.