Spiraling Approach for Angles-Only Navigation within On-Orbit Servicing Missions

On-Orbit Servicing missions possess a navigation problem for the transition from absolute to relative navigation when only using camera based relative navigation. This gap can be covered by the concept of angles-only navigation. To avoid singularities in angles-only navigation specifically trajectory profiles are designed. In this context the concept of the spiraling approach is proposed. The spiraling approach results from an eccentricity/inclination vector separation established during far formation flight superimposed by an along-track drift to initiate far range approach. The benefit for line-of-sight measurements is a change in the formation geometry and thus an alternating measurement profile. As a result specific maneuvers required during two dimensional approaches to overcome singularities within angles-only navigation are no longer necessary. In contrast they are included in the design of far formation flight and approach strategy.