Abstract
In this study, we propose an intermeshing quadrotor helicopter which has both characteristics of a tandem-rotor helicopter and an intermeshing-rotor helicopter. The helicopter has well longitudinal stability properties like the tandem-rotor helicopter and well lateral stability property like the intermeshing-rotor helicopter. The energy conversion efficiency of proposed helicopter is better than which of single-rotor helicopters. However, there are several unknown parts about its motion characteristics because such a helicopter has not existed so far. Therefore, it is necessary to conduct the motion analysis of the helicopter. In this paper, the mathematical model of intermeshing quadrotor helicopter is derived for fundamental motion analysis by using multi body dynamics technique.