A dynamic motion planning approach for an autonomous vehicle navigated without GPS and unmanned driven in unknown environments is presented. The unknown environments bring several technology challenges, including high-speed operation, complex interaction with environment, parking in unstructured lots, and passing dynamic obstacles. In this approach, we combine the global path planning and the ... [Show full abstract] local path planning with a hierarchical structure. The exploration method to navigate in unknown environments is described in detail. An autonomous vehicle, Intelligent Pioneer, was developed to verify the dynamic motion planning approach. The Intelligent Pioneer showed good performances in dynamic motion planning and won the first prize of the 2010 Future Challenge of Intelligent Vehicles in China.