Summary: | Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2007. === The successful control of a three-degree-of-freedom gyroscope is presented for the
application of steering and stabilising a platform mounted underneath an airship.
The end goal is to stabilise a camera for earth observation purposes.
The development of the necessary electronics, sensors and actuators along with
the hardware and software to interface these components are presented. This include
DC drives, torque control systems for the gimbal motors and a speed control system
for the gyroscope as well as platform angle and angular rate sensors.
A mathematical model for the gyroscope, based on Euler's equations of motion,
is presented. Non-linear simulations are performed and compared to measurements
of the plant's behaviour to step torque commands to determine the parameters of
the gyroscope. Pole placement and LQR optimal control methods are considered in
the design of a MIMO controller to steer the platform in the elevation plane, along
with a PI controller to steer the platform in the azimuth plane. Ground tests display
the success of the steering controllers.
|