Trebuchet

The trebuchet stood silent and cold. The castle walls were mockingly tall, and your siege engineers were useless. That is the problem. Trebuchet is a mobile tool that solves this specific engineering challenge: calculating the precise launch parameters for a counterweight trebuchet. It replaces guesswork with real physics, turning your phone into a dedicated ballistics computer.

Core Calculation Engine

The app operates on a physics-based model. Input your counterweight mass, projectile weight, and the length of the throwing arm. The tool instantly computes the optimal release angle and predicted range. It accounts for gravitational force (9.81 m/s²) and provides output in both metric and imperial units.

• Mass & Weight Input: Specify projectile and counterweight in kg or lbs.
• Arm Length Calibration: Adjust short and long arm ratios.
• Release Angle Finder: Computes the ideal angle for maximum distance.

Visual Simulation Mode

A 2D trajectory overlay displays the projectile’s parabolic arc. The simulation updates in real-time as you adjust sliders for pivot height or sling length. This allows for immediate visual feedback on how a single parameter change affects the impact point.

• Real-time Trajectory: Draws the full flight path.
• Parameter Sliders: Adjust pivot height and sling length.
• Impact Point Marker: Shows predicted landing zone.

Practical Tools for Engineers

Beyond basic calculation, the app includes a unit converter for force (Newtons to pound-force) and a material density reference table for common projectile materials (stone, lead, iron). A history log saves your last 50 calculations for quick recall during field testing.

• Unit Converter: Newtons, pound-force, and foot-pounds.
• Material Reference: Density values for stone, iron, lead.
• Calculation History: Stores last 50 results.

Download mobile app now to eliminate trial-and-error from your siege engineering. Convert raw data into a precise, actionable launch plan.

Requires an active internet connection for initial download and optional cloud backup features. Contains optional in-app purchases for extended calculation history and advanced material databases.