Pamoja.Mavlink 0.2.0

Pamoja.Mavlink

MAVLink v1 and v2 framing, signing, named message fields and enum values, and the mission, command, and offboard protocols. One capability of pamoja, one memory-safe Rust core with bindings for TypeScript, Python, and C#.

Install

dotnet add package Pamoja.Mavlink

using Pamoja.Mavlink;

This pulls in Pamoja.Native, the compiled engine. dotnet add package Pamoja is the whole framework in one package.

Example

The guide project's example, spliced here as it ran in CI.

From bindings/dotnet/samples/Pamoja.Guides/MavlinkGuide.cs:

const byte Vehicle = 1;
const byte Autopilot = 1;
const byte Station = 255;
const byte Planner = 190;

// An enum field travels as a number, and the dialect names each number. Printing
// the name keeps a reader from looking up what 2 or 81 means.
static string Name(string enumeration, double value) =>
    MavlinkEnum.Entry(enumeration, (ulong)value) ?? Invariant($"{value}");

// Every node broadcasts a heartbeat to say what it is and that it is alive. The
// frame wraps the payload in a header and a checksum seeded with the message's own
// value.
using MavlinkSchema heartbeatShape = MavlinkSchema.ForName("HEARTBEAT");
using MavlinkMessage announce = heartbeatShape.CreateMessage();
announce.Set("type", MavlinkEnum.Value("MAV_TYPE_GCS"));
announce.Set("autopilot", MavlinkEnum.Value("MAV_AUTOPILOT_INVALID"));
announce.Set("system_status", MavlinkEnum.Value("MAV_STATE_ACTIVE"));
announce.Set("mavlink_version", 3);
using MavlinkFrame sent = announce.ToFrame(new MavlinkHeader(Station, Planner, 0));
Console.WriteLine($"sent      {heartbeatShape.Name} in {sent.Bytes.Length} bytes");

// The vehicle answers with its own heartbeat, which reaches the station behind some
// noise and a copy with its last byte flipped in flight.
using MavlinkMessage vehicle = heartbeatShape.CreateMessage();
vehicle.Set("type", MavlinkEnum.Value("MAV_TYPE_QUADROTOR"));
vehicle.Set("autopilot", MavlinkEnum.Value("MAV_AUTOPILOT_ARDUPILOTMEGA"));
vehicle.Set(
    "base_mode",
    MavlinkEnum.Value("MAV_MODE_FLAG_CUSTOM_MODE_ENABLED")
        | MavlinkEnum.Value("MAV_MODE_FLAG_STABILIZE_ENABLED")
        | MavlinkEnum.Value("MAV_MODE_FLAG_MANUAL_INPUT_ENABLED"));
vehicle.Set("system_status", MavlinkEnum.Value("MAV_STATE_STANDBY"));
vehicle.Set("mavlink_version", 3);
using MavlinkFrame good = vehicle.ToFrame(new MavlinkHeader(Vehicle, Autopilot, 0));
byte[] garbled = [.. good.Bytes];
garbled[^1] ^= 0xFF;
byte[] delivered = [.. "???"u8, .. garbled, .. good.Bytes];

// The parser skips whatever does not start a frame and drops a frame whose checksum
// fails, so only the good copy comes out.
using MavlinkParser parser = new();
IReadOnlyList<MavlinkFrame> frames = parser.Push(delivered);
Console.WriteLine(
    $"parsed    {frames.Count} frame out of {delivered.Length} bytes,"
    + " past the noise and the garbled copy");
using MavlinkMessage heard = heartbeatShape.Decode(frames[0].Payload);
Console.WriteLine(
    $"heard     {Name("MAV_TYPE", heard.Get("type"))} on"
    + $" {Name("MAV_AUTOPILOT", heard.Get("autopilot"))},"
    + $" in {Name("MAV_STATE", heard.Get("system_status"))}");

// The base mode is a bitmask, so it names a set of flags rather than one value.
ulong baseMode = (ulong)heard.Get("base_mode");
Console.WriteLine(
    $"flags     {string.Join(" | ", MavlinkEnum.Names("MAV_MODE_FLAG", baseMode))}");
if ((baseMode & MavlinkEnum.Value("MAV_MODE_FLAG_SAFETY_ARMED")) == 0)
{
    Console.WriteLine("disarmed  MAV_MODE_FLAG_SAFETY_ARMED is not among them");
}

The same capability in every language

Documentation

• Pamoja.Mavlink reference, every type in this namespace.
• The MAVLink guide, with the same example in Rust, TypeScript, and Python.
• Every capability, and the install page.

License

MIT