Passable Height-Interval Grid Map-Based Path Planning and Control Method of Air–Ground Heterogeneous Robots Under Urban Underground Utility Tunnel

A path planning and control framework is developed for air-ground heterogeneous robots in urban underground utility tunnels. A passable height-interval grid map updated by Extended Kalman filtering provides a unified environment representation for heterogeneous robots. By combining Space-Time Theta* and model predictive control, safe cooperative navigation is achieved.