Singularities of optimal attitude motions

This paper considers the problem of planning optimal attitude motions for spacecraft. The extremal solutions that result from this optimization problem are characterized and their singularities identified. Following this these singularities are solved analytically inferring the form of particular optimal velocities. These particular solutions are then integrated and their corresponding motions derived independently of a local coordinate chart. These motions have the potential to be used as smooth, optimal reference trajectories for performing certain re-orientations for spacecraft.