When a helicopter is in flight, the rotor blades generate vibrations that travel down the aircraft’s vertical mast and into the fuselage. Left unchecked, these vibrations can shorten the operational life span of electromechanical and structural components and compromise onboard avionics systems. Passive vibration control systems absorb some of the vibration, but they cannot easily adjust to changes in rotor RPM or flight speed.
Development engineers at Korea Aerospace Industries (KAI) and Korea Aerospace Research Institute (KARI) have designed an active vibration control system (AVCS) that dynamically reduces vibrations generated by the main rotor over a range of operating conditions. A core technology of Korea’s LCH/LAH development program, the AVCS DAL-C software was developed in accordance with DO-178C using Model-Based Design with MATLAB® and Simulink®.
“We developed a dynamic model of the AVCS algorithms using Model-Based Design and following DO-178C and DO-331 standards,” says Dong-il Kwak, AVCS development program manager at KAI. “This approach enabled us to reduce design iterations, generate highly reliable C code, and then verify the code using software-in-the-loop and processor-in-the-loop testing.”