Core Concepts

Before diving in, here's how the main pieces of Sim Assist fit together.

Projects and Toolboxes

Everything starts with a Project. A project contains your scenes, models, and PLC programs.

There are two types:

Project — A complete simulation (e.g., a conveyor sorting line with scenes, PLC logic, and models)
Toolbox — A reusable collection of models (e.g., a set of conveyor components you can use across multiple projects)

[IMAGE: Dashboard showing project list with both Project and Toolbox types visible]

Scenes

A Scene is your 3D workspace. You build your automation layout here by adding models from your project or the system toolbox.

Each scene has a Component Tree — a hierarchy of all the models placed in the scene. You can nest models inside each other to create parent-child relationships (e.g., a sensor mounted on a conveyor).

[IMAGE: Scene editor with component tree panel on the left showing nested models]

Models

A Model is a 3D object with configurable parameters. Models come from:

System Toolbox — Built-in components (conveyors, sensors, actuators) available to all users
Marketplace — Components shared by other users
Your Project — Models you import yourself (GLB/GLTF files)

Each model has three types of parameters:

Parameters

General settings like position, rotation, and scale. These control how the model looks and where it sits in the scene.

Input Nodes

Sensors and detection zones that read from the scene and feed data into your PLC program. Examples:

Photoelectric sensor → tells your PLC "a box is here"
Position sensor → tells your PLC the current position of an actuator

Output Nodes

Actuators and conveyors that receive commands from your PLC program and drive the scene. Examples:

Conveyor → your PLC sets the speed
Cylinder → your PLC controls extend/retract
Spawner → your PLC triggers product creation

[IMAGE: Parameter editor showing the three tabs: Parameters, Input Nodes, Output Nodes]

PLC Programs

A PLC (Programmable Logic Controller) contains your control logic. You write it in either:

FBD (Function Block Diagrams) — Visual, drag-and-drop
ST (Structured Text) — Code-based

Each PLC program has input variables (connected to input nodes) and output variables (connected to output nodes).

How It All Works Together

┌─────────────┐     ┌──────────────────┐     ┌──────────────┐
│   Input      │     │   PLC Program    │     │   Output     │
│   Nodes      │────►│                  │────►│   Nodes      │
│              │     │   Your Logic     │     │              │
│  (sensors)   │     │   (FBD or ST)    │     │  (actuators) │
└──────┬───────┘     └──────────────────┘     └──────┬───────┘
       │                                              │
       │              ┌──────────────┐                │
       └──────────────│   3D Scene   │────────────────┘
                      │   (physics)  │
                      └──────────────┘

Every frame (60 times per second):

Sensors read — Input nodes detect objects in the scene
Program runs — Your PLC logic processes the sensor data
Outputs drive — Conveyors move, actuators extend, spawners create
Physics updates — Objects move, collide, and interact
Scene renders — You see the result in 3D

[IMAGE: Animated diagram or screenshot of a running simulation showing the cycle in action]

The Marketplace

The Marketplace lets you share and discover reusable components:

Browse toolboxes and projects from other users
Publish your own models to earn credits
Acquire free or paid components for your projects

System toolbox components (like the built-in conveyor set) are always available — no purchase needed.

[IMAGE: Marketplace browse page showing available toolboxes]

Next Steps

Quick Start — Build your first simulation in 5 minutes
Scene Editor — Learn the 3D workspace
PLC Programming — Start programming

Core Concepts

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