Abstract: In most mobile-assisted localization schemes, mobile anchors usually follow predefined scan trajectories or move randomly. When sensors are deployed non-uniformly in various terrains with complex shapes, random and predefined trajectories lead to wasted efforts in localization and uncertain localization performance. In this paper, by utilizing deployment topology information, a novel scheme of trajectory design for mobile anchor is proposed. Based on rigidity theory, the original network is first partitioned into localization units. The shortest path traversing all units is chosen as the trajectory of mobile anchor. Anchor moves along this path and localizes units in turn. Large scale simulations show that the new scheme avoids unnecessary movements and position broadcast efficiently and accommodates all kinds of deployment scenarios smartly. Compared with classic scan based trajectory, anchor travels at much shorter path and broadcasts much fewer positions.