In this paper, we aim to develop an intelligent wheelchair system with autonomous navigation capabilities, integrating functions such as localization, environment mapping, autonomous navigation, and obstacle avoidance to reduce the burden on healthcare personnel in assisting individuals with mobility issues. First, a conventional electric wheelchair is modified to receive external speed commands, transforming it into an intelligent wheelchair equipped with various sensors to perceive environmental information, laying the foundation for subsequent navigation technologies. Then, the system uses Simultaneous Localization and Mapping technology, combined with the Real-time Appearance-based Mapping algorithm, to integrate sensor data and construct accurate environmental maps. We found that using either a depth camera or Light Detection and Ranging alone has limitations, so this system combines both to improve the accuracy and stability of mapping. Finally, on the basis of the constructed environment map, the D* Lite algorithm is applied for global path planning to determine the optimal route, while the Dynamic Window Approach algorithm is used for local path planning, dynamically adjusting the intelligent wheelchair’s route to address real-time obstacle avoidance. Experimental results confirm that the system can effectively assist individuals with mobility impairments in reaching their destinations autonomously, demonstrating stable and safe navigation performance.