Abstract: A method for determining the probability of a vehicle colliding with a detected object. The object is detected. A stochastic process is determined representing a relative distance between the vehicle and the detected object. The stochastic process has a direction and a velocity relative the vehicle. A safety zone of the vehicle is defined in relation to the detected object as a straight line perpendicular to a line of sight of the detected object. The probability of colliding with the detected object over a period of time is determined as the probability of the stochastic process crossing the straight line with the direction and velocity of the stochastic process.

Abstract: A method for determining the probability of a vehicle colliding with a detected object.

Abstract: A method for synthetically calculating redundant attitude and redundant heading for an aircraft using data existing in the aircraft, including angular rates p, q, r around x-, y- and z-coordinates of an aircraft-fixed (body frame) coordinate system, air data information including speed, altitude and angle of attack, includes the steps of calculating attitude and heading based on the body-frame angular rates p, q, r, estimating errors in measured body-frame magnetic field vector components, deriving a measured body-frame field magnetic field vector, estimating errors in calculated attitude and heading using the air data and the derived measured body-frame magnetic field vector components, and correcting the calculated attitude and heading using the estimated errors in attitude and heading.

Abstract: A method for synthetically calculating redundant attitude and redundant heading for an aircraft using data existing in the aircraft, including angular rates p, q, r around x-, y- and z-coordinates of an aircraft-fixed (body frame) coordinate system, air data information including speed, altitude and angle of attack, includes the steps of calculating attitude and heading based on the body-frame angular rates p, q, r, estimating errors in measured body-frame magnetic field vector components, deriving a measured body-frame field magnetic field vector, estimating errors in calculated attitude and heading using the air data and the derived measured body-frame magnetic field vector components, and correcting the calculated attitude and heading using the estimated errors in attitude and heading.

Abstract: A method and an arrangement for synthetically calculating redundant attitude and redundant heading by means of existing data in an aircraft. In one embodiment the heading of the aircraft is available and in another embodiment the heading is calculated from a magnetic heading sensor. When the heading is available (redundant heading) attitude is calculated by weighting together the signals from and angular rate gyros (2) in the aircraft's flight control system, information from air data (altitude, speed, angle of attack) as well as information about heading (redundant heading). When the heading is not available, attitude and heading are calculated in one embodiment with the aid of Kalman filters (11, 22) by weighting together the signals from the angular rate gyros in the aircraft's control system, information from air data (altitude, speed, angle of attack and sideslip angle) as well as information from a magnetic heading detector existing in the aircraft.