First mission

The first lesson is a real simulation, not a slideshow. You take control of a rover, drive it with physics, and complete objectives that are checked against the live world. The lesson is the fastest way to see the division between USD, Modelica, Rhai, and the runtime without authoring a project first.

Before you begin

Launch LunCoSim and wait for the workbench to finish opening. You do not need to create a Twin or open a scene manually; the lesson launcher selects the authored scene and starts the lesson's Rhai scenario.

Open Scenarios → Tutorials in the menu bar. The catalog opens with the Start Here track expanded.

Option A — Lunar Rover Lab (30 minutes)

Scenarios → Tutorials → Start Here → Lunar Rover Lab

This is the recommended classroom activity. It is an exercise, so each step advances only when the simulation observes the requested result. You will:

1. Drive to a marker and stop inside it.
2. Open a speed graph and identify a real motion sample.
3. Predict the result of changing drive demand, then run two trials.
4. Explain the measured result.
5. Move a block into an authoring bay.
6. Save the result as your own Twin.

The lesson card stays visible across perspectives. Instructor checkpoints let you jump to driving, telemetry, or comparison practice without pretending the earlier tasks were completed. Restart whole lab (discard edits) resets the document through the normal scene restart.

Option B — First Drive (5 minutes)

Scenarios → Tutorials → Sandbox → First Drive

Use this when you only want to see the core loop:

1. Open the lesson.
2. Click Take control.
3. Drive to the glowing flag.
4. Stop inside the marker.

The rover's motion comes from the authored Modelica controller and the native physics engine. The lesson script observes possession, the flag sensor, and the rover's speed; it does not advance from elapsed time.

The lesson card names the current objective and the actions that are valid now. Progress is checked against the live simulation.

Reading the lesson card

The card shows the current objective and the actions that are valid now. Some actions are mouse buttons in the card, some are keyboard controls, and some are buttons that open another perspective.

The lesson uses semantic input hints such as forward, brake, and left. The displayed key is resolved from your current input bindings, so re-binding an action changes both the actual control and the lesson text. See Controls.

A tour and an exercise look similar but behave differently. A tour advances when you choose Next; an exercise waits for the world. If an exercise card does not advance, the current objective has not been observed yet. Read the objective and the hint before assuming the application is stuck.

Driving the rover

Selection is not control. Clicking the rover selects it; it does not send your input to it. Use Take control in the lesson card, or click the input endpoint, before driving.

The default bindings are:

Action	Default
Forward	W
Reverse	S
Steer left	A
Steer right	D
Brake	Space
Release control	G
Pause	P

The lesson displays the bindings that are actually configured, not a hardcoded key name. If a binding reads unbound, the action has no key and the lesson cannot be completed with the keyboard until you assign one in Settings → Keybindings.

What just happened

Under the lesson there is a normal Twin:

• A USD scene owns the rover, the ground, the flag, the camera, and the sensors.
• A Modelica model owns the rover's continuous drive behavior.
• A Rhai scenario owns the lesson steps, hints, objectives, and completion checks.
• The runtime projects the scene into physics, steps the model, and delivers events back to the scenario.

That division is the main idea behind LunCoSim. The lesson is not a special mode with a separate physics implementation; it is an authored scene and an authored scenario running through the production runtime.

If the lesson does not advance

Symptom	Likely cause	What to do
The rover ignores input	You have not taken control	Click Take control or the input endpoint
The rover moves but the marker does not trigger	You stopped outside the marker radius	Drive fully inside the glowing area and stop
The card shows a key that does nothing	The binding is unbound or remapped	Open Settings → Keybindings and check the action
The viewport is empty	The lesson scene did not load	Reopen the lesson; check the status bar for an asset hold
The rover rolled over	The slope or speed exceeded the authored limit	Use Right rover, then approach more slowly
A graph is empty	The simulation is paused or the channel is not selected	Resume, then select a live channel in Telemetry

After the lesson

Continue with Create a Twin to turn a working scene into your own project, or read How it fits together to understand the layer boundaries in more detail. If you want to inspect the values behind the lesson, open Inspect telemetry.