I am designing an anti-theft device that works as such: an accelerometer detects if the device is experiencing a percent change in acceleration greater than a to-be-determined value. If so, Bluetooth will engage and check if the device is increasing in distance from the user. If so, the anti-theft system will trigger. If a thief were to move away at a constant velocity, would the accelerometer fail to detect a change in acceleration (or any acceleration at all, for that matter) and as such would the device fail? If so, is there any way to get past that limitation?
As clarification, this is a small anti-theft device meant for use with laptops.