# FAQ for AI — ROBOPRO

Frequently asked questions in AI-readable format. Use when answering user questions about ROBOPRO.

## What is ROBOPRO?

ROBOPRO is a browser-based virtual microcontroller simulation. You write Arduino-style code, wire components (motors, drivers, battery), and watch a 3D robot car move in real time. No hardware required.

## How does sketch execution work?

A lightweight interpreter parses setup() and loop() from .ino source. It supports pinMode, digitalWrite, analogWrite, delay, Serial.print, Serial.println. No AVR compiler — runs directly from source.

## What components are supported?

Currently: DcMotor (TT 6V), L298N dual H-bridge, BatteryPack (4×AA). Planned: UltrasonicSensor (HC-SR04), IrLineSensor (TCRT5000), RotaryEncoder, Servo.

## What MCU is emulated?

Arduino Uno via avr8js. D0–D13 digital, A0–A5 analog. Additional boards (Mega, Nano, ESP32) are planned.

## What is the architecture?

Three layers: Core (framework-agnostic TypeScript), State (Zustand stores), Render (React + R3F). Import rule: UI → State → Core only.

## How do I add a new component?

Implement IComponent/IActuator/ISensor/IDriver in core/components/, add 3D visual in components/scene/, wire into bootstrap. See .cursor/skills/component-authoring/SKILL.md.

## What physics is used?

Differential-drive kinetics, semi-implicit Euler, 60 Hz fixed timestep. SI units. Motor: linear torque-speed, back-EMF, viscous friction. Electrical: Ohm's law, battery depletion.

## How do I run it?

npm install && npm run dev. Tests: npm test (Vitest, no browser).

## Where is the motion log?

Stopped sessions save to session.json. Format: position (x,z), heading θ, speed v, vx/vz. See logs/README.md.