Quick Start: ArduPilot

Hardware requirements

• SkyHub v3 device.
• Drone running ArduPilot flight controller with firmware 4.* or higher.
• Mounting parts to install SkyHub.
• SkyHub3 cable for Pixhawk autopilot or cable provided by drone manufacturer to connect SkyHub with autopilot.
• Power output (according to SkyHub required input power).

Software requirements for the Windows PC

• UgCS v5.10.2 or higher (referred to below as UgCS)
• UgCS Custom Payload Monitor v4.3.0 or higher (referred to below as UgCS-CPM)
• MissionPlanner for ArduPilot configuration.
• WinSCP (optional) to access the SkyHub file system for advanced configuration.

UgCS desktop download and setup process

• Download the installation package.
• Run the setup file.
• Read and acknowledge the license agreement.
• In the component selection tab, select ArduPilot to install necessary autopilot compatibility.

• Installation complete.

UgCS Custom Payload Monitor download and setup process

• Download the latest available CPM version.
• Run the setup file.
• Select the SkyHub license file for the SkyHub you will be using.

• Read and acknowledge the license agreement.
• Installation complete.

Physical setup

• Mount SkyHub on the drone in a safe, fixed position.
• Connect SkyHub Connector #3 (red) to the flight controller using the SkyHub 3 cable for Pixhawk autopilot (or cable provided by drone manufacturer).
• Connect SkyHub to a power source.

UgCS configuration

• Make sure UgCS version 5.10.2 or higher is used (download links can be found in the Prerequisites section) and VSM for ArduPilot vehicles is installed.
• Configure UgCS ArduPilot VSM. Open vsm-mavlink.conf in a text editor with administrator privileges. The file is located in the UgCS installation folder (default path: C:\\Program Files (x86)\\UgCS\\bin). Find, uncomment, and adjust the following lines:

• Establish an Auxiliary connection between UgCS-CPM and SkyHub. See Preparation guide for instructions.
• When the Auxiliary link is established, you should select it from the Link menu in UgCS-CPM.

• ArduPilot configuration for SkyHub - On the autopilot, it is necessary to configure the serial port to which SkyHub will be connected.

Parameters:

• Enabling MAVLink autopilot on SkyHub

In CPM, press the Settings button, choose SkyHub Autopilots from the menu, and enable MAVLink. Press Save and choose to reload the system to apply changes.

If the autopilot configuration matches the default settings in SkyHub, the drone connection indicator in UgCS-CPM must turn green.

• Verify the connection on ArduPilot using Mission Planner. In Mission Planner, open Setup -> Advanced -> MAVLink inspector.

• In case of correct connection and configuration, the MAVLink inspector shows communication between SkyHub and the autopilot.

Vehicle 2 and Comp 5 correspond to the configured SkyHub System (2) and Component (5) ID.

• In case of correct autopilot, UgCS, and SkyHub configuration, Payload data b64 is displayed in the drone telemetry in UgCS.

Altimeter setup

When the Altimeter is connected to SkyHub

• Connect the altimeter to the SkyHub Connector #1 (yellow).
• Navigate to the “Payload” section.
• Enable the driver for the Altimeter you will use, and confirm the reload.

• Next, in the UgCS-CPM software, navigate to the “All settings” section.
• From the drop-down list, select “Mavlink settings”.
• Make sure that the “Use SkyHub altimeter” option is enabled.
• Make sure that the “Use drone altimeter” option is disabled.
• Click the “Save” button and confirm reload.

• Click the drop-down list again and select the “Altimeters” section.
• Set the default altimeter to your model (in our example, Ainstein US-D1). Click “Save” and confirm reload.

• Go back to the main menu and click the “Start” button.
• From the drop-down list, select your altimeter (in our example it is “Altimeter: Ainstein US-D1”) and press the “+” button.

• Altimeter configuration is complete.

When the altimeter is connected directly to the drone

• Connect the altimeter to your drone.
• In the UgCS-CPM software, navigate to the “All settings” section.
• From the drop-down list, select “Mavlink settings”
• Make sure that the “Use SkyHub altimeter” option is enabled.
• Make sure that the “Use drone altimeter” option is enabled.
• Click the “Save” button and confirm reload.

• Click the drop-down list again and select the “Altimeters” section.
• Set the default altimeter to “Mavlink (autopilot)”. Click “Save” and confirm reload.

• Go back to the main menu and click the “Start” button.
• From the drop-down list, select “Altimeter: MAVLINK” and press the “+” button.

• Altimeter configuration is complete.

Configuring ArduPilot to Report Ellipsoidal Height (HAE) Instead of AMSL

By default, ArduPilot reports GPS altitude as height above Mean Sea Level (AMSL), which is calculated using a geoid model. For many precision survey and mapping applications — including bathymetric and photogrammetric workflows — it's preferable to work with ellipsoidal height (Height Above Ellipsoid, HAE) instead, since this is the raw geometric height reported directly by the GPS receiver relative to the WGS84 reference ellipsoid, without any geoid correction applied.

Configuration steps

• Connect your ground station to the autopilot. Open Mission Planner and connect to the flight controller
• Navigate to the Config section and click on the Full Parameter List

• Use the search or filter function to find the parameter named: GPS_DRV_OPTIONS

• Press the Set Bitmask option and check Use ellipsoid height instead of AMSL

• Write and save the parameter

• Power-cycle or reboot the flight controller so the new setting takes effect.
• Configuration is complete.