H. Predicting Accidents
Principle of relative motion is used to predict the accidents.
Inertial Navigation System (INS) is used which uses the touch
screen, motion sensors (accelerometers) and rotation sensors
(gyroscopes). It calculates via dead reckoning (calculating new
position using previous position) the position, orientation, and
velocity (direction and speed of movement) of a moving object
without the need of external reference. By tracking both the
current velocity and acceleration of the system measured
relative to the moving system, it is possible to determine the
linear acceleration of the system in the inertial reference frame.
Performing integration on the inertial accelerations (using the
original velocity as the initial conditions) using the correct
kinematic equations yield the inertial velocities of the system,
and integrating again (using the original position as the initial
condition) yields the initial position. Iterations take place
regularly in an interval of 15 seconds and the colliding car's
position is displayed on the map. For instance, if the observer
knew where approaching vehicles was pointing and what was
its velocity before, it is possible he to keep track of how car
turned and how much it has accelerated or decelerated. So the
position of cars at any instant in a radius of 500 meters are
shown with purple arrows on the map and the one having the
shortest time of intersection is displayed with details like time
for collision, distance between point of collision and current
point are displayed on the top of the screen with minimum
estimate time of collision.