Abstract:
No one can deny the significant role of gliders in founding the aviation industry, so
far in its evolutionary progress. Gliders are eco-friendly as they exploit the energy
from the atmosphere from mother nature without a necessity for a power plant and
they remain a loft in air by soaring utilizing the updrafts and air currents.
Nevertheless, they are still limited in aspects of range, endurance, speed, control and
stability. However, nowadays, the aviation industry seeks to go green as a result of
the great air pollution caused by the large amounts of smokes and gases generated
from the massive amount of fuel combustion. Maybe using modern automation
technologies and making use of some glider’s features, but at the same time maintain
the performance and the efficiency of the modern aircrafts can lead to new green
innovations in the field of aviation. This thesis is proposing a design of a controller
for the Hiway Demon hang glider to guarantee the stability of the system with
certain level of performance and to enhance the system’s rejection to the
disturbances affecting it drastically during soaring. The controllers are designed
using classical (Inversion Formula) control technique and advanced (robust) control
technique. The nonlinear state-space model of the aircraft is linearized. After that,
it is decoupled into lateral and longitudinal models. The longitudinal model is
reduced to short period model in order to facilitate the analysis and the design of the
controllers. The pitch rate channel is stabilized, while the lateral model suffered of
instability problems, but a suggestion proposing to apply a Multi-DOF controller on
the model in the near future. The controllers are evaluated in terms of disturbance
rejection, noise attenuation and control efforts. The robust control approach has
exhibited better convenience for such application than the classical control approach
especially in term of disturbance rejection.
