Vehicle Trajectory Method for Intercepting an Alerted, Evading Contact

摘要

This report deals with the determination of a vehicle trajectory that will resultin intercept of an alerted, evading contact. One of the classical problems associated with vehicle employment is the calculation of those parameters necessary for a vehicle trajectory to result in either intercept of a contact or for the vehicle to be delivered to a location that is suitable for the internal seeker system of the vehicle to detect and home on the contact. The primary parameters associated with such a problem are: vehicle deflection or gyro angle, intercept time, and seeker turn-on time. The general problem entails determining those parameters that are necessary for employment of a vehicle on an intercept trajectory. For the acoustic torpedo employment problem, this requires determining the straight-line trajectory that results in the laminar point of the weapon intercepting the target. Wherein the standard approach assumes that the contract being pursued maintains a constant course speed, the approach presented in this report deals with a contact that is alerted and take evasive action. It is presumed that information, with regard to the expected alertment range of the evader, is available, and that an alertment strategy is selected. A key aspect of this formulation is that alertment time is not required to be known a priori. The main torpedo parameters to be determined include gyro angle, alertment time and intercept time. Other parameters such as vehicle run and enable run (run-to-seeker turn-on) are related and are readily computed.