FRC 2026 Shooter Tuning Tool

System Overview

This tool analyzes a two-wheel shooter system commonly used in FRC robotics competitions. The system consists of:

Two sides/axes - The shooter has two independent sides (left and right), each with its own wheel assembly
Wheels per side - Each side can have one or more wheels mounted on the same axis (typically 1-2 wheels per side)
Motors per side - Each side is driven by one or more motors connected in parallel to share the load
Flywheel assembly - Each wheel assembly has a flywheel attached to store rotational energy and maintain consistent ball exit velocity
Gear reduction - Motors are connected to the wheel axis through a gearbox to optimize torque and speed
Ball compression - The ball is compressed between the two counter-rotating sides, creating friction that transfers energy

System Architecture: In a typical two-wheel shooter, you have two sides (left and right) that rotate in opposite directions. Each side consists of a wheel assembly mounted on a common axis. The wheel assembly can have one wheel (single wheel per side) or multiple wheels stacked together (dual/triple wheel configuration). All wheels on the same side rotate together at the same RPM, driven by one or more motors connected through a gearbox. The flywheel is typically attached to the same axis as the wheels to store rotational energy.

How it works: The ball is fed between the two counter-rotating sides. As the wheels spin, they compress the ball and transfer rotational energy through friction. The ball exits at a velocity determined by the wheel surface speed and compression characteristics. Each side operates independently with its own motor(s), gearbox, and flywheel, allowing for precise control of exit velocity.

Analysis: This tool calculates optimal shooter angles, required wheel RPMs for different distances (8-20 feet), and evaluates system performance metrics including spin-up time, speed consistency, and motor headroom. The analysis accounts for air drag, ball compression/slip between sides, and flywheel energy storage effects. All motor and gear ratio specifications are per-side (each side has its own motor configuration). The number of wheels per side affects the total moment of inertia (MOI) of the flywheel assembly.

Configuration

Motor Type

Wheels per Side Number of wheels mounted on each side/axis (1 = single wheel, 2+ = stacked wheels)

Motors per Side Number of motors driving each side (motors are connected in parallel on the same axis)

Current Limit (A) Maximum current per motor to prevent overheating

Gear Ratio Motor speed reduction ratio (higher = more torque, lower wheel RPM)

Flywheel Configuration Flywheel mass affects energy storage and speed consistency

Custom MOI (lb-in²) Moment of inertia of your custom flywheel assembly

Shooter Angle (deg) Launch angle of shooter mechanism (leave empty to find optimal)

Idle Speed (RPM) Wheel RPM when shooter is idle (reduces spin-up time)

Drag Coefficient Air resistance coefficient (foam ball typically ~0.5)

Ball Incoming Velocity (m/s) Velocity of the ball before entering the shooter (from feeding mechanism). Reduces the velocity the wheels need to add.

Slip/Compression Factor Ratio of wheel surface speed to ball exit velocity. Accounts for ball compression (ball deforms when squeezed, reducing effective contact radius) and slip between ball and wheels. Formula: wheel_surface_speed = ball_exit_velocity × slip_factor. Typical values: 1.0 = no slip/compression (ideal), 1.10-1.20 = typical for foam balls, 1.15 = recommended default.

Wheel Type Select wheel type - diameter and MOI will be set automatically

Custom Wheel MOI (lb-in²) Moment of inertia for your custom wheel

Wheel Diameter (inches) Diameter of the shooter wheels (auto-updated when wheel type is selected)

Motor Efficiency Mechanical efficiency of motor and gearbox (typically 0.80-0.90)