Operator TUI

Welcome to the Motion-Stack Operator — a simple, text-based terminal user interface for interactively driving your robot’s legs, joints, wheels, and inverse-kinematics via ROS 2. This guide will walk you through launching, and basic usage of the TUI (textual user interface) and the keyboard inputs.

Quick Start

Launch the operator

From the ~/Motion-Stack/ directory:

bash launch_operator.bash

Enjoy the TUI

You’ll see a simple terminal menu and a floating window.

• The TUI (terminal) is unable to move any joint by itself, it only selects modes, changes behaviors and displays state.

• The floating (red) window intercepts keyboard-strokes only when focused by the OS (click on it to focus). These strokes will move joints.

• PS4 controller inputs will move joints.

TUI Overview

When you launch the operator, the screen is divided into:

• Header:

• Mode shows your current menu (main, leg_select, joint_select, etc.).

• Legs shows which legs are selected (green) vs. unselected (red).

• Body: the menu or controls for the current mode.

• Footer (“Logs”): the last few status messages (leg discovery, errors, recover/halt calls, etc.).

Menu Walkthrough

Mode Selection Menu

Button	Action
Leg Selection	choose individual joints (and direction) for direct velocity control.
Joint Selection	choose individual joints (and direction) for direct velocity control.
Wheel Selection	choose wheel-mode (continuous turn) joints for linear/angular drive.
IK Selection	choose legs with IK available for Cartesian control.
Recover / Halt	send robot-specific “recover” or “halt” commands to selected legs.
Quit	exit the operator cleanly.

Note

Navigate with the arrow keys (or mouse), then press ↵ Enter to select.

Leg Selection:

• You’ll see a checkbox next to each discovered leg (e.g. “leg 1”, “leg 2”).

• Toggle individual legs on/off with Space or by clicking the checkbox.

• (Optional) Press ✔ Confirm Selection to apply.

Note

If you don’t pick any, all legs become selected by default.

Joint Selection:

• A row of speed radios appears at the top: Low • Med • High.

  • Choose your desired joint velocity scale.

• Below, joints are grouped by leg (color-coded).

  • Click a joint’s tri-state box:

    • [ ] = off

    • [X] = forward (left click)

    • [R] = reverse (right click)

• You can select all joints of the specific leg just by clicking the checkbox next to the “Leg N”.

• Clearing or going back is as simple as the ✖ Clear All or ← Back buttons.

• Joint-owned joints are grayed out in the Wheel pane.

Wheel Selection:

• Same pattern as Joint Selection, but for wheel joints.

• Choose your wheel-speed scale from the top radios.

• You can select all joints of the specific leg just by clicking the checkbox next to the “Leg N”.

• Wheel-owned joints are grayed out in the Joint pane.

IK Selection:

• Legs with a working IK solver show up as checkboxes.

• Disabled legs read “Leg N (No IK)”.

• Choose one or more legs, then drive their end-effector with your controller.

Controls & Keybindings

TUI Navigation

| Key / Mouse           | Action                                           |
|-----------------------|--------------------------------------------------|
| **↑ / ↓**             | Move focus up/down through menus or lists        |
| **← / →**             | Move focus left/right between columns in grids   |
| **Enter / Space**     | Activate a button or toggle a checkbox           |
| **Mouse Left-Click**  | Click buttons / toggle checkboxes                |
| **Mouse Right-Click** | Toggle **reverse** for joints in joint and wheel modes|

Drive Mode Keybindings

| Mode           | Keys               | Description                                |
|----------------|--------------------|--------------------------------------------|
| **Leg Select** | ↓ or **l**         | Select **all** legs               |
|                | 1–9                | Select that numbered leg                   |
| **Joint Mode** and **Wheel Mode**   | **w** / **s**      | Positive / negative joint velocity |
|                | **0**              | Send selected joints to zero position      |
|                | **o** / **l**      | Wheels forward / backward                  |
|                | **p**              | Stop all wheels                            |
| **IK Mode**    | Gamepad sticks & triggers | Cartesian end-effector control    |
|                | **x** / **o**      | Toggle IK frame: base-relative / ee-relative |

Recover & Halt Commands

| Key                 | Action                         |
|---------------------|--------------------------------|
| **Enter**           | Recover **selected** legs      |
| **Shift + Enter**   | Recover **all** legs           |
| **Space**           | Halt **selected** legs         |
| **Shift + Space**   | Halt **all** legs              |

Customizing & Extensions

Robot-specific subclasses

Create your own OperatorNode in a separate package to add:

• New services (Recover/Halt)

• Other operational modes

• Additional keybindings

Environment variable

Set the OPERATOR environment variable e.g. export OPERATOR=operator1 to use a namespace and avoid interferences with other operators on the network.

Troubleshooting

No legs discovered?

• Check your /legN/joint_alive services are running.

Buttons unresponsive

• Ensure your keyboard (or joystick) topic namespace matches OPERATOR.