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An aerodynamic model, for a minimally actuated flapping wing micro air vehicle (FWMAV), is derived from blade element theory. The vehicle considered in this work is similar to the Harvard RoboFly, except that it is equipped with independently actuated wings. A blade element-based approach is used to compute both instantaneous and cycle-averaged forces and moments for a specific type of wingbeat motion that enables nearly decoupled, multi-degree-of-freedom control of the aircraft. The wing positions are controlled using oscillators whose frequencies change once per wingbeat cycle. A technique is introduced, called Split-Cycle Constant-Period Frequency Modulation with Wing Bias, that provides a high level of control input decoupling for vehicles without active angle of attack control. This technique allows the frequencies of the upstroke and downstroke of each wing to differ such that non-zero cycleaveraged drag can be generated. Additionally, a wing bias term has been added to the wingbeat waveform and is utilized to provide pitching moment control. With this technique, it is possible to achieve five degree-of-freedom control using only two physical actuators. The present paper is concerned with the derivation of the instantaneous and cycle-averaged forces and moments for the Split- Cycle Constant-Period Frequency Modulation with Wing Bias technique. Implementation of the wing bias is discussed and modifications to the wingbeat forcing function, which are necessary to maintain a continuous wing position, are made.