Getting Started

This guide covers installation, platform configuration, and the most common usage patterns.

Table of Contents

1. Prerequisites
2. Installation
   1. .NET CLI
   2. Package Manager Console (Visual Studio)
   3. PackageReference (.csproj)
3. Platform Setup
4. High-Level API — RPLidar
5. Low-Level API — RpLidarSerialDevice
6. Reading Device Info and Health
7. Working with LidarPointGroup
8. Scan Modes
9. Next Steps

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Prerequisites

• .NET SDK 5.0+ (or any .NET Standard 2.0-compatible runtime)
• A SLAMTEC RPLidar sensor: A1M8, A2M8, or A3M1
• The USB-to-serial adapter that ships with the sensor

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Installation

.NET CLI

dotnet add package RpLidar.NET

Package Manager Console (Visual Studio)

Install-Package RpLidar.NET

PackageReference (.csproj)

<PackageReference Include="RpLidar.NET" Version="*" />

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Platform Setup

Platform	Port Format	Notes
Windows	COM3, COM4 …	Check Device Manager → Ports
Linux	/dev/ttyUSB0, /dev/ttyUSB1	Run sudo usermod -aG dialout $USER and re-login
macOS	/dev/cu.usbserial-*	No additional setup required
Raspberry Pi	/dev/ttyUSB0	Same as Linux

On Linux and Raspberry Pi, always add your user to the dialout group before running. Otherwise the serial port open will fail with a permission error.

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High-Level API — RPLidar

The RPLidar class is the quickest way to start scanning. It automatically connects, sends a reset, and begins scanning using the Sensitivity (Ultra-Capsule) mode.

using RpLidar.NET;

// Pass the serial port name; baud rate defaults to 115200
using var lidar = new RPLidar("COM3");

lidar.LidarPointScanEvent += points =>
{
    Console.WriteLine($"Received {points.Count} points in this sweep");

    foreach (var pt in points.Where(p => p.IsValid))
    {
        Console.WriteLine($"  Angle: {pt.Angle,6:F1}°  Distance: {pt.Distance,7:F0} mm  Quality: {pt.Quality}");
    }
};

Console.WriteLine("Scanning — press Enter to stop.");
Console.ReadLine();
// Disposal calls Stop() automatically

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Low-Level API — RpLidarSerialDevice

Use RpLidarSerialDevice with a LidarSettings object when you need full control over scan mode, motor PWM, event interval, or maximum distance filtering.

using RpLidar.NET;
using RpLidar.NET.Entities;

var settings = new LidarSettings
{
    Port              = "COM3",
    BaudRate          = 115200,
    ScanMode          = ScanMode.Sensitivity, // Standard | Boost | Sensitivity
    MaxDistance       = 12000,               // millimetres — discard farther points
    Pwm               = 660,                 // motor speed 0–1023
    ElapsedMilliseconds = 400               // ms between LidarPointScanEvent fires
};

using var device = new RpLidarSerialDevice(settings);

device.LidarPointScanEvent      += OnScanReceived;
device.LidarPointGroupScanEvent += OnGroupReceived;

device.Connect();
device.Start();

Console.ReadLine();

device.Stop();
device.Disconnect();

// -----------------------------------------------
static void OnScanReceived(List<LidarPoint> points)
{
    // Called every ElapsedMilliseconds with raw points
    Console.WriteLine($"{points.Count} points");
}

static void OnGroupReceived(LidarPointGroup group)
{
    // Called with angle-indexed group (0.1° resolution)
    Console.WriteLine($"Group has {group.Count} unique angles");
}

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Reading Device Info and Health

// Must call Connect() first
device.Connect();

var info = device.SendRequest(Command.GetInfo) as InfoDataResponse;
if (info != null)
{
    Console.WriteLine($"Model      : {info.ModelId}");
    Console.WriteLine($"Firmware   : {info.FirmwareVersion}");
    Console.WriteLine($"Hardware   : {info.HardwareVersion}");
    Console.WriteLine($"Serial No. : {info.SerialNumber}");
}

var health = device.SendRequest(Command.GetHealth) as RpHealthResponse;
if (health != null)
{
    // Status: 0 = Good, 1 = Warning, 2 = Error
    Console.WriteLine($"Health     : {health.Status}  Error code: {health.ErrorCode}");
}

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Working with LidarPointGroup

LidarPointGroup stores scan points indexed by angle at 0.1° resolution. It is useful for map-building, obstacle detection, and comparing consecutive sweeps.

LidarPointGroup previous = null;

device.LidarPointGroupScanEvent += group =>
{
    // Access a specific angle
    var pt = group[90];             // nearest point at 90°
    var ptF = group[180.5f];        // nearest point at 180.5°

    // Noise-filtered point list
    var filtered = group.Filter();

    // Compare with the previous scan (1.0 = identical, 0.0 = completely different)
    if (previous != null)
    {
        double similarity = previous.Compare(group);
        Console.WriteLine($"Scene similarity: {similarity * 100:F1}%");
    }

    previous = group;
};

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Scan Modes

Mode	Enum Value	Protocol	Supported Sensors	Notes
Standard	ScanMode.Standard	Scan (0x20)	A1M8, A2M8, A3M1	Most compatible, lower sample rate
Boost	ScanMode.Boost	Express Scan, mode 3	A2M8, A3M1	Higher sample rate
Sensitivity	ScanMode.Sensitivity	Ultra-Capsule, mode 4	A2M8, A3M1	Default — best accuracy and range

Boost and Sensitivity modes are not supported on the A1M8. Using them will silently fall back to Standard scan at the firmware level.

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Next Steps

• API Reference — Complete class and member documentation
• Support — How to report a bug or request a feature