SITL Forge - FPV Laboratory is a physics-first quadcopter simulator and engineering workbench. We aim to reproduce the behavior of real motors, propellers, and batteries as accurately as possible — model parameters are fitted to bench measurements where available, so simulated flight tracks the trends you'd see on real hardware. Validate builds, optimize efficiency, and learn flight tuning with realistic feedback, without crashes, burned components, or wasted money.
This is not just a flying simulator — it's a laboratory for designing, analyzing, and flying real-world multirotor systems.
RC controller required!
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Why SITL Forge - FPV Laboratory?
- Test motor and prop combinations before buying real hardware
- Predict thrust-to-weight, current draw, and flight time from real spec data
- Validate heavy-lift builds and payload configurations safely
- Learn PID tuning and rate setup with instant, risk-free feedback
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1000Hz Physics, Calibrated to Real Hardware
The VMG (Voltage-Motor-Generator) engine runs a full torque-balance simulation at 1000Hz using Jolt Physics. Component models are calibrated against bench measurements wherever possible:
- Motor iron losses (eddy current + hysteresis) calibrated from real dyno data
- Per-propeller thrust and torque coefficients fitted across multiple motor+prop combinations
- LiPo discharge with voltage sag, internal resistance, and state-of-charge tracking
- ESC dead-time losses, timing advance, current limiting, and thermal derating
- Aerodynamic drag via virtual wind tunnel with shader-based surface analysis
- Vibration injection into simulated gyro and accelerometer sensors
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Built-In Flight Controller
Fly out of the box with a built-in PID flight controller in ACRO, ANGLE, and HORIZON modes. Tune PID gains and rates in real time. Perfect for learning, prototyping, rapid testing, and benchmarking a build before committing to real firmware.
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Virtual Workbench
A real-time engineering workspace for building and analyzing quadcopters:
- Thrust-to-weight ratio, max current draw, hover throttle, and flight time estimates
- Throttle sweep analysis with efficiency curves
- Payload attach/detach simulation
- Multiple frame sizes, motors, and propellers based on real-world specs
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Procedural Motor Audio
Procedural motor audio generated from RPM, current, and thrust — no samples, fully dynamic. Blade-pass harmonics, electromagnetic whine, aero noise, and sub-bass rumble respond instantly to throttle changes.
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Built for Precision
- 1000Hz physics tick rate with Jolt Physics engine
- FPV camera with lens distortion, chromatic aberration, and vignetting
- Real-time OSD: altitude, speed, battery voltage, per-cell monitoring, motor outputs
- Debug graphs for any telemetry channel
- Force visualization: thrust vectors, drag forces, center of mass/pressure markers
- Full joystick and RC transmitter support with per-device mapping
- Session persistence — layouts, builds, and settings saved automatically
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Extensible With Optional DLC
The simulator is built around an open integration interface. Optional DLC packs add bridges to real flight-controller firmware running in software-in-the-loop mode — the built-in flight controller is replaced with actual firmware while the same physics continues to drive the airframe. Sold separately.
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Who Is This For?
- FPV pilots testing setups before building real drones
- Drone engineers and hobbyists learning multirotor system behavior
- Builders validating heavy-lift and payload configurations
- Anyone curious about the physics behind a quadcopter
