Experimental verification of roll-angle control using air-jet pulse-actuation

This paper deals with an application of the on-off control method that is based on the principle of equivalent areas (PEA), to roll-angle control of a single-axis rotation platform mechanism, which is built to simulate the rolling motion of a miniature air-born machine, such as vertical take-off and landing (VTOL) vehicle. This is actuated by air-jet pulses, whose amplitude is constant but whose width is adjusted in each fixed time-period, called the PEA period. The pulse is generated only once during the PEA period such that the areas under the pulse signal and a servo signal are equal. This servo signal is what would have been generated if a servo-type actuator is used. The I-PD controller is designed and implemented digitally at a high control frequency of 1 kHz. Experiments are carried out for the roll-angle controller on the platform to show that the performance of the controller using on-off valves is comparable to that using servo valves.