Browser terminal: embed IPython in viser via terminado + xterm.js

[siddhss5]

Goal

Access the full IPython console from the browser — same tab as the 3D viewer, no separate terminal needed. Anyone with browser access can control the robot.

Approach

• terminado — WebSocket-to-PTY bridge (what Jupyter uses). Wraps the existing IPython session.
• xterm.js — terminal emulator in the browser. Connects to terminado WebSocket.
• Embed xterm.js in a Viser tab via add_html.

Architecture

Browser
  ├── Viser 3D view (port 8080)
  ├── Chat tab (Viser GUI)
  ├── Sensors tab (Viser GUI)
  └── Terminal tab (xterm.js → terminado WebSocket on port 8081)

geodude process
  ├── IPython session (robot, ctx, chat available)
  ├── Viser server (port 8080)
  └── terminado server (port 8081, connected to IPython PTY)

What this enables

• Send a URL → anyone can control the robot from a browser
• LLM chat for non-programmers, terminal for power users, same session
• Remote access to the real robot (via SSH tunnel or direct)
• No local install needed for observers/collaborators

Scope

• Single shared IPython instance (all browser clients see the same session)
• Per-user instances (via JupyterHub) is a future enhancement for teaching

Lives in

geodude (console.py) — terminado wraps geodude's IPython, not a generic mj_viser feature.