Analytic synthesis by means of normalized diagrams of the autopilot for an airline jet

M.E. Penati, M. Zanzi, M. Crisci

Department of Electronics, Computer Science and Systems

Bo-lo-gna University, Viale Risorgimento 2, 40135 Bologna

Phone: 051-2093036, Email: gbertoni@deis.unibo.it

 

As it is known, the mathematical model of an aircraft is, generally, of a non linear type. How-ever, by means of suitable approximations, not only can this model be linearized, but it can also be decoupled into two parts of which one represents the so-called lateral dynamics and the other the so-called longitudinal dynamics. Despite these simplifications, for the design of the autopilot the classic synthesis procedures (frequency domain or root locus methods) are, generally, rather cumbersome.

A more suitable way of designing the autopilot is using a method proposed by the au-thors and based on normalized diagrams which links the parameters of systems having a dy-namic order not greater than three to the parameters of the outputs to some canonical input. This method is valid both when the require-ments regard the pa-rameters of an output to a canoni-cal in-put and when the requirements re-gard the assignment of a few of the system's poles.

Actually, the above mentioned linearized models are of a dynamic order greater than three but they contain some parts that are difficult to control and observe and, therefore, they can be reduced by using the well known SVB (Singular Value Balancing) method.

In this paper the analytic synthesis of the autopilot for an aircraft of large dimensions is presented using the nu-merical data of a Boeing 747.