| Autonomous flight at low altitude with vision-based collision avoidance and GPS-based path following Recent countries visiting this post |  |
 | 8 | United States |
 | 1 | Germany |
 | 1 |
| Autonomous flight at low altitude with vision-based collision avoidance and GPS-based path following Recent countries visiting this post | |
| 8 | United States |
| 1 | Germany |
| 1 |