Design and control of a small quad-rotor system under practical limitations

This paper presents design and control of a small quad-rotor system for control education. Our goal is to develop a low cost quad-rotor system that is affordable for public use such as education or RC hobby. Based on experiences gained from the previous Flymobile system that has capabilities of both flying and driving, a new quad-rotor system is designed to fit practical cost. Several limitations on implementing a quad-rotor system are taken into account to reduce the cost. Firstly, the size is reduced to have the better maneuverability. Secondly, control hardware is limited to an 8 bit processor such as an AVR to reduce the cost as well. Thirdly, algorithms related with control and sensing tasks are required to be shortened in order to minimize the calculation time to fit the sampling time for the available processor. A small quad-rotor system is implemented after satisfying all the practical limitations. Experimental studies are conducted to confirm control and operational abilities of the system.