A CONTROL ALGORITHM FRAMEWORK FOR TIME-OF-ARRIVAL AND ARRIVAL AIRSPEED CONTROL

摘要

This paper documents the framework for a control algorithm which commands an aircraft to arrive at a specified final location with constraints on arrival time, airspeed, and heading in an environment with steady state wind and turbulence. The path is defined as a variable-length racetrack, allowing for an accurate estimate of the arrival time which can be quickly changed by increasing or decreasing the size of the racetrack. The arrival time is estimated using Gaussian quadrature which allows for the inclusion of steady state wind into the arrival time estimate. The time-of-arrival error between the estimated and the desired arrival time is then minimized through real-time path and airspeed control. A sensitivity study was performed which varied aircraft performance, wind speed, wind direction, arrival time and magnitude of turbulence. The results show the controller achieved a time-of-arrival error of less than one second and arrival airspeed error less than four meters per second across all simulations with moderate turbulence and wind speed less than one third the desired airspeed of the vehicle.