1. Localization in Lot Map of Lot User Input Return Park Query Other Cars for Path Clearance Plan Route to Optimal Spot Receive Optimal Spot Query for Path Clearance Plan Optimal Route Navigate to Exit Navigate to Spot Notify User Park Cars No Cars

2. Park Localization of Car Establish Communication Select Best Spot Plan Best Route Navigate to Spot Obstacle Detected? Reached Spot? Park in Spot Plan Route to Exit Navigate to Exit Obstacle Detected? Tell Other Cars

3. Park Navigate to Entrance Queue Localization of Car Establish Communication Select Best Spot Plan Best Route Navigate to Spot Determine Navigation Goal Reached Exit? Park in Spot Navigate to Exit Obstacle Detected? Join Exit Queue Reached Spot? Notify User Return Y N Avoid Obstacle Y NN N Y

4. Change Status Receive Confirma tion Exit Spot Correctly Enter Exit Queue Change Status Disconne ct Communi cate with Other Cars LOCALIZA TION Plan Route Navigate to Destinati on Navigate to Entrance Queue Establish Network Connecti on Change Status Obstacle Detected? Destination Reached? Other Cars on Network? Receive Best Spot Other Cars on Network? Choose Best Spot Park Correctly in Spot Change Status Parking or Returning ?