Iterative Pseudostate Method for Transfer Trajectory Design of Interplanetary Orbiter Missions

A proposed method based on the pseudostate technique identifies the four distinct transfer trajectory design options available for an opportunity with the parking orbit inclinations fixed for an interplanetary orbiter mission. Though design options differ by about 0.06 deg in the departure right ascension of ascending node and about 0.07 deg in the departure argument of periapsis, they result in completely different arrival parking orbit angles [RAAN]. Further, the numerical method cannot identify these design options without additional boundary condition on arrival hyperbola when the patched conic design is used as the initial guess. On the other hand, each of the proposed design options, when used as initial guess for numerical refinement, converges to the corresponding arrival geometry, thus generating four distinct numerical designs. The differences in the departure parking orbit angles (RAAN and AOP) and between the proposed and V-infinity tuned patched conic designs are about 0.6 and 0.3 deg, respectively, for the minimum energy opportunity of 2018. This difference is because of inclusion of the sun�s gravity within the pseudosphere in the proposed method. The proposed design reduces the deviation in target conditions. The deviation in the time of periapsis is also greatly reduced by about 95%. The designs obtained using the proposed method are very close to the numerical designs. Also, the computation time taken by the proposed method to generate designs for departure epochs spanning one year is 0.1 s, which is comparable to the 0.08 s taken by the V-infinity tuned patched conic method.