Drone flies towards object if drone is surrounded by objects inside safety distance

[MaritaHaavisto]

Safety distance is set to 2m. Drone is surrounded by 4 object that are in square and obstalces are located 1.5 m away from drone center.

Actual Result: Drone does take-off and then it starts dodging the obstacles and needs to be taken into manual control to avoid crashing to obstacle

Expected Result: Drone should notice during take-off that its surrounded by obstacles and land immediately and cancel mission?

[matemat13]

Starting the drone that close to an obstacle is generally not a great idea. During takeoff, only PixHawk is controlling the drone's position, so there's no collision avoidance and it's possible that the drone may crash into the obstacle due to wind, imprecise GPS etc. and there's nothing we can do about it.

To make sure that this doesn't happen in practice, we've implemented a check for obstacles that will disable arming the drone if there are any obstacles too close to it or if bumper data is unavailable. This is part of the new pull request to version 0.1.1 (PR#26 in navigation, PR#27 in control_interface and PR#11 in fog_msgs). So when those PRs are merged, this should no longer happen.