Landing Operation¶

Flight Path Approach¶

The ARC system supports UAV approach from all directions of the landing pad. The recommended UAV altitude at approach is 10-70m above the landing pad.

Landing Sequence¶

The landing sequence when using ArduPilot’s Land or PX4s Precision Land mode in combination with the ARC system is shown in the figure below.

Figure 8: ARC Automatic Landing Sequence phase diagram

• Phase 1: UAV approaches the landing pad under manual Pilot control or via an autonoumous mission.

• Phase 2: The ARC Primary device detects the landing pad and issues Precision Landing Target messages to the Flight Controller. The Flight controller will then initialise the landing system and notify the ground controller. On Ardupilot the message console will show "PRECLAND: TARGET FOUND and PRECLAND:INIT COMPLETE"

• Phase 3: Pilot or autonomus mission switches control to ArduPilot LAND mode to listen to ARC positional targets, and position the UAV above the target.

• Phase 4: Once the UAV has reached the landing zone, the descent phase will begin, and ARC will guide the UAV to the configured landing point.

Configuration¶

To configure the system to use Landing mode, you will need to complete the relevant Flight Controller configuration steps:

• ArduPilot Configuration
• PX4 Configuration

Tether Operation¶

The Landing Target information provided by the ARC system can also be used to support UAV tethering behaviour via the ArduPilot LOITER mode. UAV tethering refers to an operational mode where the UAV moves towards and then holds a set position and altitude above a target point.

When using the ARC system to provide input information into ArduPilot LOITER mode, this target point is kept updated constantly, allowing the UAV hold position to track the movement of the ARC landing pad constellation. This in turn allows for tracking and follow behaviour if the landing pad is mounted on, for example, a moving vehicle.

Flight Path Approach¶

The flight path approach for Tether mode is the same as described in the Landing Operation section.

Tether Commencement Sequence¶

The sequence for commencing ArduPilot LOITER mode using the ARC system is shown in Figure 9 and described below.

Figure 9: ARC Automatic Tethering Sequence phase diagram

Phase 1: UAV approaches the landing pad under manual Pilot control or via an autonoumous mission.

• Phase 2: The ARC Primary device detects the landing pad and issues Precision Landing Target messages to the Flight Controller. The Flight controller will then initialise the landing system and notify the ground controller. On Ardupilot the message console will show "PRECLAND: TARGET FOUND and PRECLAND:INIT COMPLETE"

• Phase 3: Pilot or autonomus mission switches control to ArduPilot LOITER mode to listen to ARC positional targets, and position the UAV above the target.

• Phase 4: Once the UAV has reached the tethering point, the uav will maintain the same height above the landing pad, and will center its position above the configured point. If ardupilot is configured for moving targets, the UAV will replicate any X or Y or Z axis motion.

Configuration¶

To configure the system to use Landing mode, you will need to complete the relevant Flight Controller configuration steps:

• ArduPilot Configuration
• PX4 Configuration