Frequently Asked Questions

Common questions about HID ROS 2.

General

What is HID ROS 2?

A framework for integrating USB Human Interface Devices with ROS 2 using a schema-driven approach.

Why use HID instead of serial/Ethernet?

Standard protocol: No custom drivers needed
Plug-and-play: OS handles enumeration
Bidirectional: Input and output in one connection
Low latency: Fast polling rates (up to 1000 Hz)

What devices are supported?

Any USB HID-compliant device, including:

Custom microcontroller projects
Gaming peripherals
Industrial sensors
Input devices

Schema and Configuration

Can I change the schema after deployment?

Yes, but you’ll need to rebuild and the firmware must match. The schema is the contract between firmware and ROS 2.

Do I need to write URDF?

No! URDF is automatically generated from your YAML schema.

Can I have multiple HID devices?

Yes, each gets its own hardware interface instance with different VID/PID.

Development

How do I debug my device?

Use the inspect_device tool:

ros2 run hid_tools inspect_device --vid 0xVVVV --pid 0xPPPP

My values are wrong, what’s the issue?

Common causes:

Byte order (use little-endian)
Wrong type in schema
Firmware struct not packed: __attribute__((packed))

Can I use this with Arduino?

Yes! Use a HID-capable Arduino (Leonardo, Micro, etc.) and the generated HID descriptor.

Advanced Usage

Can I create custom controllers?

Yes! HID ROS 2 works with any ros2_control controller. See Custom Controllers.

What’s the maximum data rate?

Limited by USB HID polling rate (typically 1000 Hz max) and report size (typically 64 bytes max per report).

Can I send commands to the device?

Yes! Define outputs in your schema to create command interfaces.