DESIGN OF AN INTUITIVE FLIGHT CONTROL SYSTEM

摘要

This paper deals with the design of an integrated airplane control system for vertical flight path and airspeed control using the Total Energy Control System (TECS) concept. TECS supports a full complement of automatic and augmented manual control modes. The basic vertical path control mode of TECS is Flight Path Angle (FPA), which has been proposed as the basis for an augmented manual control mode. Direct manual FPA control is a control strategy, whereby the pilot closes the control loop directly on the flight path angle. Such a control strategy including flight envelope protection functions is believed to simplify the flying task, provide care-free handling characteristics and enhance safety. The main topics addressed in this paper include 1) design of the innerloop feedbacks controlling the rotational degrees of freedom of pitch, roll and yaw, using Nonlinear Dynamic Inversion (NDI), to normalize the aircraft’s angular responses over its full envelope and eliminate the need for traditional gain scheduling; 2) design of the pilot vertical control inceptor feed forward commands to achieve desirable handling qualities for the augmented manual FPA control mode; 3) implementation and evaluation of the basic automatic and augmented manual TECS modes in MATLAB?/SIMULINK? and integration into the experimental system of the DLR research aircraft ATTAS (Advanced Technology Testing Aircraft System); 4) in-flight testing of the TECS Manual FPA control mode by computer-generated “pilot inputs”. The results obtained so far have demonstrated the feasibility of the Nonlinear Dynamic Inversion based innerloop design and validated that the FPA response dynamics satisfy level 1 handling qualities requirements.