[info]The contents of this document apply only to the Skydio X10D with Microhard radio. The X10D SkydioLink (SL) does not support any of the documented features. For questions or assistance, please reach out to IntegrationSupport@skydio.com[/info]

Control Interface

Skydio X10D MH implements the Robotics and Autonomous Systems - Air (RAS-A) MAVLink Control Link Interoperability Profile (IOP). RAS-A is a MAVLink dialect with extensions to accommodate autonomous systems and their capabilities. There are related efforts, e.g. RAS-G, that have no relationship to MAVLink. RAS-A also includes standardization around video, e.g., protocols, codecs, and metadata. X10D supports RAS-A protocol version 1.2, along with additional custom messages that extend its functionality beyond the standard. There are also some known deviations from RAS-A, enumerated below.

Known Deviations from RAS-A v1.2

• X10D does not fully implement Gimbal Protocol V2.   
• X10D does not support the “white on” value for the LED_ILLUM_MODE parameter.
• X10D extends the RAS-A In-Band Pairing Protocol to support changing component IP addresses and alters timeout thresholds to be more reliably achievable with available radios.
• Only cylindrical geofences are supported. Geofences only support the no_action and hold geofence actions.
• X10D exclusively supports UDP for RAS-A Wireless Pairing communications protocol

Custom Extensions

X10D implements some custom behaviors, messages and other RAS-A extensions, with the intent to standardize them whenever possible.

Attitude Mode

Attitude Mode is a less-assisted flight mode that can be entered automatically as a failsafe (if both GPS and visual navigation fail) or intentionally. In this mode, the drone will use internal barometer readings to maintain altitude when the throttle joystick is centered. Use the joysticks to adjust roll and pitch movements to maintain the drone’s position. The drone will not automatically hold position or brake when the joysticks are centered.

Obstacle Avoidance is not available in attitude mode.

Visit How to fly X10D in Attitude Mode for additional information, some of which is specific to Skydio’s Flight Deck Ground Control Station. To explicitly switch into Attitude Mode via MAVLink:

• Switch the drone mode to ALTCTL prior to arming, arm the drone, throttle down, and then throttle up to initiate launch.
• Altitude mode can also be entered during flight by switching the drone mode to ALTCTL.

Low Launch

Skydio X10D can launch in confined environments, both indoors and outdoors, with a reduced minimum overhead clearance requirement by enabling the Low Launch feature. The default required height is 3m of overhead space. Low launch changes this to 2m, with a target takeoff altitude of 1m. This feature is not available in Attitude Mode or with obstacle avoidance disabled. For more details, see the Release Notes. Low launch mode persists across reboots and is enabled by setting the MAVLink LOW_LAUNCH parameter (see Supported MAVLink Parameters). 

MAV_CMD_PILOT_DEFINED_VEHICLE_GPS - WIP

MAV_CMD_PILOT_DEFINED_VEHICLE_GPS allows the pilot/GCS to manually specify the global pose of the drone. The intended purpose of this message is to support global frame telemetry and tasking in the absence of GNSS or other global position estimates. Only the MAV_FRAME_GLOBAL frame is supported. It has a message ID of 51051.

This message will have no effect if GPS is enabled on the drone. Disable GPS on the drone prior to sending this message by setting the custom MAVLink parameter GPS to 0 (see Supported MAVLink Parameters).

This message is a work-in-progress and subject to change. It should not be relied upon in production environments.

Night Flight

Skydio X10D can fly at night with or without the nightsense attachment. Both configurations require special configuration prior to flight.

Without a Nightsense Attachment

Flying without Nightsense requires the pilot to disable obstacle avoidance and night autonomy functionality. First, disable obstacle avoidance by setting the COM_OBS_AVOID parameter to 0. Next, set AUTO_NAV_MODE parameter to 2.0 (AUTONOMY_OFF).

After both parameters have been set, begin arming the vehicle. At this point, the vehicle should prompt to start a hand-wave calibration. It does so by sending a STATUSTEXT message and, if the navigation lights are enabled, by flashing yellow lights. After hand-wave calibration, arming should complete and the X10D is ready for flight.

With a Nightsense Attachment

X10D can fly with obstacle avoidance enabled at night using the Nightsense attachment. This requires the pilot to set the AUTO_NAV_MODE parameter to 5.0 (NIGHT_AUTONOMY) and the NIGHTSENSE_ON parameter to 1.0 (ON). These parameters must be set in order. After both parameters have been set, arming the vehicle should complete and the X10D is ready for flight.

[note]There is no need to disable obstacle avoidance when flying with a nightsense attachment. If the X10D requests a hand-wave calibration with the Nightsense attached, re-check the above parameters. Hand-wave calibration is not required for Nightsense flights and if the drone requests it nightsense is not active.[/note]

Dynamic Channel Switching

An implementation of the Skydio X10D Dynamic Channel Switching feature is available as an extension to the MAVLink mission protocol, incorporating MAV_MISSION_TYPE_RADIO. MAV_CMD_DO_SET_RF is used to set the desired channel-bandwidth pairs, and MAV_CMD_DO_DCS_ENABLE is used to toggle DCS’ active state. The same restrictions as the Skydio first-party implementation apply (ex., bandwidths must all match and the user is limited to 16 frequencies).

• MAV_CMD_SET_RF (5550)

• MAV_CMD_DO_DCS_ENABLE (5551)

Fixes and Updates in SW version 39.327

• HOME_POSITION.altitude is now set to Height Above Mean Seal Level (AMSL) of the vehicle before takeoff, rather than after launch.
• Updated GLOBAL_POSITION_INT.relative_alt and ALTITUDE.altitude_relative to report the same altitude of height above HOME_POSITION. This accounts for changes in HOME_POSITION.altitude set after launch.
• Added RAS-A compliant Autonomy Engine Component
• Zoom to HFOV capability
  • Allows zooming to a desired horizontal field of view (HFOV) using MAV_CMD_SET_CAMERA_ZOOM with ZOOM_TYPE_HORIZONTAL_FOV
  • Current HFOV is communicated to the user via CAMERA_FOV as well as VIDEO_STREAM_INFORMATION and VIDEO_STREAM_STATUS
• Extended parameters handled by the correct component
  • Each camera component handles its corresponding extended parameters

Media Interfaces 

Video

X10D supports RTP or RTSP video delivery. Which video protocol is used is determined by the configuration on the vehicle. Only one of RTP or RTSP can be active at a time.

RTP 

RTP video is delivered using the AVC (H.264) codec. Many RTP clients, such as VLC, mplayer, and gstreamer, require a .sdp file to configure RTP. Below are valid .sdp files for the EO and IR camera streams.

eo.sdp  

v=0  

o=- 0 0 IN IP4 127.0.0.1  

s=No Name  

c=IN IP4 127.0.0.1  

t=0 0  

a=tool:libavformat 55.2.100  

m=video 5600 RTP/AVP 96  

a=rtpmap:96 H264/90000  

a=fmtp:96 packetization-mode=1  

ir.sdp  

v=0  

o=- 0 0 IN IP4 127.0.0.1  

s=No Name  

c=IN IP4 127.0.0.1  

t=0 0  

a=tool:libavformat 55.2.100  

m=video 5900 RTP/AVP 96  

a=rtpmap:96 H264/90000  

a=fmtp:96 packetization-mode=1   

RTSP

RTSP video is also delivered using the AVC (H.264) codec, and additionally multiplexes KLV metadata into an MPEG-TS container. More details about the specific metadata included are available in the Video metadata section.

There are separate endpoints for each camera stream using RTSP. The URIs to specify with many common clients, including ffplay, VLC, and gstreamer, are as follows:

rtsp://<vehicle_ip_address>:5554/subject (EO stream)

rtsp://<vehicle_ip_address>:6554/infrared (IR stream)

Video metadata

When using the RTSP video option, X10D includes video metadata in accordance with the MISB 0601 UAS Datalink Local Set standard and the MISB ST 0903 Video Moving Target Indicator Metadata standard5.

UAS Datalink Metadata (MISB ST 0601)

MISB ST 0903 Video Moving Target Indicator Metadata Table

Network Interface

Skydio X10D uses a Microhard pMDDL1624 radio module. The default drone-side configuration of the radio is to be in “Master” mode with a randomized network ID and encryption password established at pairing time with a Skydio Controller. The drone radio can be reconfigured via a variety of interfaces documented below. Note: While all of the documented configuration methods in this document will allow the user to select any center frequency, topology, and bandwidth supported by the pMDDL1624, Skydio only tests and verifies a subset of these configurations. The center frequencies and bandwidths tested and supported in Skydio’s first-party Flight Deck GCS are as follows:

The full set of Microhard-allowed center frequencies and bandwidths are as follows. Skydio does not make any guarantees about performance or reliability in these additional configurations. Users should thoroughly test these configurations independently before using them in any performance-sensitive context.

Wired Pairing

The X10D supports wired and manual pairing via the back USB-C port, located under the rubber cover directly above the drone battery. This requires the host computer to support the CDC-ECM driver. Most Linux and MacOS computers have a compatible driver by default. On a successful connection, the X10D will assign the host computer a DHCP address in the 192.168.11.0/24 address space.

Wired pairing occurs via HTTP POST requests to the vehicle and is a two-step process:

1. Request a bearer token:

a) A bearer token can be requested from the following endpoint and with the provided JSON request body where the client_id (1-32 characters) is set to be the client requesting the token.  

b) The API will then respond with the bearer token as a subelement of the “data” JSON array labeled “accessToken”.  

2. Request a settings change after the bearer token is received: 

   a) RF radio settings - include channel, bandwidth, mode, network ID, and encryption key.  

• All settings must be given and have values be requested, or the request will be rejected.  
• Bandwidth and Mode must be requested with their microhard enum value (e.g., a bandwidth of 8 MHz would use a value of 0).  
• Invalid radio frequency and bandwidth combinations will not be checked on an interface level and will silently fail to be set.  
• Network ID and encryption keys that are too short/too long (< 8 char or > 63 char) will not be checked on an interface level and silently fail to be set. 

b) LAN settings - include subnet and netmask.

Default Network Settings  

• Drone Radio 
  • IP Address: 192.168.42.1  
  • Network Mask: 255.255.255.0  

• Drone MAVLink Interface  
  • IP Address: 192.168.42.10  
  • Port: vehicle is listening on port 15667  
  • Protocol: UDP  

• Ground Station Radio  
  • IP Address: 192.168.42.2 (default; optionally modified)  
  • Network Mask: 255.255.255.0 (default; optionally modified)  

• Ground Station  
  • Configure as 192.168.42.0/24 while avoiding the 192.168.42.1, 192.168.42.2, and 192.168.42.10 addresses (already assigned elsewhere)  
  • DHCP is OK (typical default setting for Microhard radios)

If the request is successful:

 If the request is unsuccessful: 

File-based Radio Configuration

The Skydio X10D supports a file-based radio configuration method, enabling the rapid duplication of radio settings across multiple drones. To initiate reconfiguration, users must place a file named pair_request.json at the root of the filesystem on an exFAT-formatted USB drive and insert it into the back USB port. The drive must be inserted prior to beginning vehicle arming. 

The X10D will parse the file and apply the settings. On success, the drone’s LEDs will flash green. On failure, they will flash red. In both cases, a pair_response.json file will be written to the USB drive.

DO NOT turn off the vehicle immediately after receiving the positive response light, as this may result in your desired settings not being fully applied

The format for pair_request.json is as follows

{

  "request" : "connect",

  "hostname" : "gcs-0001",

  "drivers" :

  [

    {

      "type" : "Microhard",

      "bandwidth": 4, # MHz

      "radio_topology": "access-point", # RAS-A Topology

      "frequency": 1863, # MHz

      "network_id": "StringToBeUsedAsNetworkId", # 1-64 char

      "encryption_password": "StringPassword" # 8-63 char

      "ip_address" : "192.168.42.1",

      "remote_ip_address" : "192.168.42.10"

    },

  ],

}

In the case of successful reconfiguration, pair_response.json will look as follows

{

  "response" : "connect",

  "hostname" : "vehicle-0080",

  "drivers" :

  [

    {

      "type" : "Microhard",

      "accepted": true,

      "bandwidth": 4,

      "radio_topology": "access-point",

      "frequency": 1863,

      "network_id": "StringToBeUsedAsNetworkId",

      "encryption_password": "StringPassword"

      "ip_address" : "192.168.42.1",

      "remote_ip_address" : "192.168.42.10"

    },

  ],

}

Pair_response.json will contain a descriptive error message if the reconfiguration fails.

Wireless Pairing

Skydio X10D implements the Robotics and Autonomous Systems - Air (RAS-A) MAVLink Control Link Interoperability Profile In-Band Pairing specification with extensions for IP configuration and multiple paired drones.

The battery power button is used to put the X10D into pairing mode. The sequence of button presses is TAP, TAP, HOLD. In the case of HOLD, hold for about one second. In the case of TAP, press and release quickly. The drone’s arm lights will turn purple when it successfully enters pairing mode.

It is important to note that the Skydio vendor specific default pairing security key is 1234567890, bandwidth is 1 MHz, and frequency is 1823 MHz. Additionally, when configuring during Pairing and Reconfiguration, bandwidth and frequency/channel must be provided in MHz, while encryption_password and network_id must follow the same requirements as listed below in “Manual Pairing”.

The vehicle’s pairing implementation allows reconfiguration of both the vehicle and its radio’s IP. When making changes the vehicle and radio must both be placed in the same /16 subnet where the first two octets are 192.168, the fourth octet is 1 for the radio and 10 for the vehicle, and the third is between 200 and 250. A valid example configuration would be 192.168.206.1 for the radio and 192.168.206.10 for the vehicle. If desired the subnet mask can also be specified using CIDR notation. If not provided, the radio and vehicle will be set to the most conservative netmask for the given settings (ie. /24). These settings can be configured both during Pairing and Reconfiguration by providing ip_address for the radio and remote_ip_address for the vehicle.

Manual Pairing

The X10D radio can be manually configured at http://192.168.11.1/radio when the vehicle is plugged into a computer supporting Ethernet over USB. 

1. Enter RF Channel, Channel Bandwidth, Radio Mode, Network ID, and Encryption Password. 
   1. Channel refers to a valid MH frequency (ie. 1840)
   2. Network ID must be 1-64 characters
   3. Encryption Password must be 8-63 characters
2. Select the Configure RF Settings button to request acceptance.
3. Reconfigure the microhard radio IP from this page via the IP Address configuration tool and the Configure LAN button. However, the IP should be reset via the Reset LAN Configuration for OTA button before applying any vehicle updates. 

Validation & Testing Guidance

Configuring and Pairing a Microhard Dev Kit

This section provides guidelines for getting started with a development kit; please refer to the Microhard Operating Manual and support at https://support.microhardcorp.com/portal/en/home for more details on configuration and troubleshooting. 

Suggested hardware:

• A Microhard development kit (or any other pMDDL1624 module), e.g., Microhard pMDDL1624-ENC (https://www.microhardcorp.com/pMDDL1624-ENC.php)  
• Antenna for 1600-2500 MHz with SMA connector, e.g., https://www.amazon.com/Cellular-Compatible-Wireless-Industrial-Security/dp/B0C58V4Y3B/

Quick Setup steps:

• Attach antennas to MH 
• Connect an ethernet cable to the LAN port 
• Attach power cable (device will power up) 
• Wait ~60 seconds for boot -> monitor LED status 
• Log in from a browser (these values all assume default configuration)
  • http://192.168.168.1 
  • User: admin 
  • Password: admin 

• Change the IP address to 192.168.42.2 

• Network -> LAN -> IP address: 192.168.42.2 
• Network -> LAN -> Netmask: 255.255.255.0 
• Apply changes 

• Bridge the LAN & WAN interfaces 

• Network -> WAN -> Working Mode: Bridged with LAN Port 

• Apply Changes 

• Configure the RF Settings using the Wired Pairing instructions above in this document 

Connecting to X10D with a MAVLink Ground Control Station

MAVLink Ground Control Stations (GCS) intended for use with flight stacks such as PX4 or Ardupilot generally work well with X10D but may experience issues based on dialect-specific assumptions that differ from the RAS-A IOP. Older versions of QGroundControl, for example, may fail based on the absence of some PX4-specific parameters on X10D. Below are brief connection instructions for QGroundControl and MAVProxy.

QGroundControl

1. Navigate to:   QMenu > Comm Links
2. Populate the options as shown in the screenshot below. Note that it is necessary to add the target host. The default IP of the X10D host is 192.168.42.10 on the Microhard network.

MAVProxy

mavproxy.py --master=udpout:192.168.42.10:15667  

Skydio, Inc. A0553