Classification of solar sail attitude dynamics with and without angular momentum^*

This paper describes attitude dynamics properties of spinning, momentum-biased and zero-momentum solar sail spacecraft. The model called "Generalized Sail Dynamics Model" (GSDM) is introduced, which can deal with general and practical sail configurations, such as arbitrary optical property distribution, shape and surface wrinkles. Attitude stability criteria and other key dynamical characteristics are derived and compared by compact analytical equations induced from the GSDM. The newly derived zero-momentum sail dynamics is compared with that of spinning and momentum-biased sails. It is shown that the spinning and momentum sails have an advantage in terms of dynamical stability whereas zero-momentum sails are only statically stable. With this special property, angular momentum-stabilized sails can realize a Sun-pointing stable attitude with almost zero-fuel, which are discussed with actual space flight experience of the JAXA’s two interplanetary missions, IKAROS and Hayabusa2.