Hardware
========

.. image:: media/figures/h2_product.png
   :width: 60%
   :align: center
   :alt: Unitree H2 Full-Size Humanoid Robot
   :class: mbsrounded

|

Component Overview
------------------

The Unitree H2 is a full-size bionic humanoid composed of an upper body and a lower body with a highly
articulated, modular structure. It provides a total of **31 degrees of freedom**, enabling expressive,
human-like whole-body motion for locomotion, balancing, gesturing, and manipulation.

Each **leg** provides **six degrees of freedom** (hip, thigh, knee, and ankle joints) for stable, dynamic
locomotion. Each **arm** provides **seven degrees of freedom**, supporting a wide manipulation workspace. A
**3-DOF waist** and **2-DOF head** enhance balance, motion coordination, and environmental perception.

Degrees of Freedom
------------------

+----------------------+------------------------------------------+
| **Category**         | **Specification**                        |
+======================+==========================================+
| **Total DOF**        | 31                                       |
+----------------------+------------------------------------------+
| **Single Leg DOF**   | 6                                        |
+----------------------+------------------------------------------+
| **Single Arm DOF**   | 7                                        |
+----------------------+------------------------------------------+
| **Waist DOF**        | 3                                        |
+----------------------+------------------------------------------+
| **Head DOF**         | 2                                        |
+----------------------+------------------------------------------+

Joint Actuators
===============

The H2 uses Unitree's self-developed electric joint actuators, engineered for high torque density, dynamic
response, and precise closed-loop control. Selected joints deliver peak torque up to **360 N·m**, and dual
encoders provide high-resolution position and velocity feedback for accurate state estimation and whole-body
coordination.

+-------------------------------+----------------------------------------------+
| **Parameter**                 | **Specification**                            |
+===============================+==============================================+
| Actuator Type                 | High-performance electric (PMSM)             |
+-------------------------------+----------------------------------------------+
| Peak Joint Torque             | Up to 360 N·m                                |
+-------------------------------+----------------------------------------------+
| Feedback                      | Dual encoder (position + velocity)           |
+-------------------------------+----------------------------------------------+

.. note::

   Joint ordering, limits, and reference frames used by the control SDK are defined in the official
   `H2 Developer Guide <https://support.unitree.com/home/en/H2_developer>`_. Always confirm joint indices
   against the SDK header definitions before sending low-level commands.

Perception
==========

Vision
------

The H2 integrates a **humanoid binocular camera** with a wide field of view, providing visual and depth
perception for navigation, interaction, and manipulation. The forward-facing configuration supports
perception-driven behaviours and human–robot interaction.

Proprioception
--------------

An onboard **IMU** combined with per-joint dual encoders provides the proprioceptive sensing required for
balance, contact estimation, and stable whole-body locomotion control.

Tactile (Optional)
------------------

When equipped with optional **dexterous hands**, the H2 gains tactile sensing for fine manipulation and
controlled object interaction.

Onboard Computer
================

The H2 ships with a high-performance AI compute platform rated at up to **2070 TOPS**, providing substantial
headroom for onboard perception, planning, and multimodal model inference.

+--------------------------------------+--------------------------------------------------------------+
| **Parameter**                        | **Specification**                                            |
+======================================+==============================================================+
| **AI Compute**                       | Up to 2070 TOPS                                              |
+--------------------------------------+--------------------------------------------------------------+
| **Workloads**                        | Perception, planning, multimodal inference                   |
+--------------------------------------+--------------------------------------------------------------+

.. important::

   For security reasons, change any default login credentials after first access and follow proper shutdown
   procedures before performing hardware or software modifications.

Power System
============

The H2 is powered by a **quick-release smart battery**, enabling fast swaps to extend operating sessions.
Runtime is approximately **3 hours**, depending on workload and configuration.

+-------------------------------------------+----------------------------------------------+
| **Parameter**                             | **Specification**                            |
+===========================================+==============================================+
| Battery                                   | Quick-release smart battery                  |
+-------------------------------------------+----------------------------------------------+
| Runtime                                   | ~3 hours (configuration dependent)           |
+-------------------------------------------+----------------------------------------------+
| Swap                                      | Quick-release for fast exchange              |
+-------------------------------------------+----------------------------------------------+

.. warning::

   Always verify that the battery is fully latched before operation. If the H2 will be stored for an extended
   period, remove the battery pack. Handle batteries according to lithium-battery safety guidelines.