It is easy to construct maps with traditional simultaneous localization and mapping (SLAM). With the flourishing development of SLAM, many SLAM functions have been implemented. The research proposes the Gmapping algorithm based on the Rao-Blackwellized Particle Filters (RBPF) to raise the accuracy of maps. Compared to the others, the proposed SLAM algorithms adopting orthogonality only to construct accurate maps can not only align the initial map automatically, but also reduce the complexity. It can effectively enhance the accuracy for the exploration of low-end laser rangefinders. Moreover, it achieves the functions of real-time localization, mapping, and indoor navigation, and supports higher exploration efficiency than traditional SLAM algorithms.