FRC

Robotics Calculator

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Drive

Drivetrain Traction / μ

Mechanisms

Shooter Arm & Pivot Elevator Intake & Index

Climber

AM Climber Tube Lengths

Power & Motion

Electrical Gearing HTD-5 Belt

Auto

Projectile Auto Profile

Drive Traction Shooter Arm Elevator Intake Climber Tubes Power Gearing Belt Shot Auto

Drivetrain

Free speed, peak force, and acceleration.

Motor & Gearing

Motor (per side) Kraken X60 Falcon 500 NEO NEO Vortex CIM 775pro

Motors / side

Gear ratio

Wheel diam (in)

Robot weight (lbs)

Efficiency (%)

Target 12–16 fps free speed. Acceleration >15 ft/s² is excellent.

Common Swerve Ratios

Mk4i L18.14:1

Mk4i L26.75:1

Mk4i L36.12:1

Mk4i L45.14:1

MAXSwerve L15.50:1

MAXSwerve L25.08:1

MAXSwerve L34.29:1

Swerve X L17.85:1

4" wheel at 6.75:1 with NEO ≈ 14.5 fps free speed.

Traction & Wheel Slip

Max traction force and empirical μ measurement.

Traction Calculator

Wheel type Colson / Nitrile (μ=1.1) Traction wheels (μ=0.9) Mecanum (μ=0.7) Omni (μ=0.5) Smooth / carpet (μ=0.3) Custom (empirical)…

Normal force (lbs)

Slip force (lbs)

Effective μ

Robot weight (lbs)

Traction wheels

Drag a weighted wheel across carpet with a fish scale. μ = slip force ÷ normal force.

μ Reference

Colson / Nitrile on carpet1.1

Traction wheels on carpet0.9

Mecanum on carpet0.7

Omni on carpet0.5

Smooth wheel on carpet0.3

Wet / slick surface0.2

Traction limit = μ × weight. Exceeding it = wheel slip before motor stall.

Flywheel Shooter

Rim speed, kinetic energy, and energy transfer.

Shooter Config

Motor Kraken X60Falcon 500 NEONEO Vortex

Motor count

Ratio (m:fw)

Flywheel diam (in)

Flywheel mass (lbs)

Ball mass (lbs)

Target exit (fps)

KE ratio ≥ 2× = minimal RPM drop. Double flywheel mass for single-wheel shooters.

KE from RPM

Flywheel RPM

Flywheel diam (in)

Flywheel mass (lbs)

Ball mass (lbs)

Hood shooters transfer ~80% of flywheel kinetic energy to the ball.

Arm / Pivot

Gravity torque, safety factor, and angular speed.

Motor Kraken X60Falcon 500 NEOCIM

Motor count

Gear reduction

Arm length (in)

Arm + load (lbs)

Efficiency (%)

Safety factor ≥ 2× required. Add gas spring if marginal. Aim for 90–180°/s.

Elevator / Linear

Lift force, safety factor, and speed for cascade elevators.

Motor Kraken X60Falcon 500 NEOCIM

Motor count

Gear reduction

Drum radius (in)

Load mass (lbs)

Cascade stages 1 — single2 — cascade3 — triple

Each cascade stage multiplies linear speed and force proportionally.

Intake & Indexer

Roller surface speed, transit time, and flywheel feed timing.

Intake Roller

Motor NEONEO Vortex NEO 550BAG Kraken X60

Ratio (m:roller)

Roller diam (in)

Game piece diam (in)

Intake speed should be 1.5–3× drive speed to prevent jamming.

Indexer / Conveyor

Indexer type Flat belt (1:1, 2" pulley) Roller pair (1:1, 2" OD) Tube indexer (1.5:1, 3") Snap-action Colson (2:1, 4") Polycord / V-belt (1:1, 2") Custom…

Motor NEONEO 550 BAGKraken X60

Ratio (m:roller)

Roller diam (in)

Path length (in)

Shooter target RPM

Feed game piece when flywheel ≥ 95% of target RPM.

Common FRC Indexer Types

Flat Belt

Flat belt conveyor

8–18 fps

Low friction, consistent

Roller Pair

Compression rollers

10–20 fps

Good for round pieces

Tube Indexer

Compliant tube

6–14 fps

2023-style note/cone

Snap-Action

Colson roller

12–24 fps

Fast cycle, less compliant

Polycord

V-belt / polycord

10–16 fps

2022 cargo common

Serpentine

Multi-roller belt

8–14 fps

Versatile path routing

AndyMark Climber in a Box

Pull force, safety factor, climb speed, and current draw.

Kit Config

Preset AM Climber 10.5:1 (CIM) AM Climber 21:1 (CIM) AM Climber NEO swap 10.5:1 Custom…

Motor Kraken X60Falcon 500 NEOCIM

Gear reduction

Motor count

Efficiency (%)

Spool radius (in)

Robot weight (lbs)

Climb height (in)

Climb Analysis

Time available (s)

Hook height (in)

Rope / strap type Dyneema / Spectra (0% stretch) Nylon webbing (~2%) Bungee (~5%)

Stock AM spool ≈ 0.75" radius. 10.5:1 for <100 lbs, 21:1 for heavier robots.

Climber Tube Lengths

Required lengths for 1, 2, or 3-stage telescoping climber arms.

Parameters

Target climb height — robot bottom to bar (in)

Mount height (in)

Hook length (in)

Min overlap (in)

Wall thickness (in)

Number of stages 1 stage — single tube 2 stage — cascade 3 stage — triple cascade

Stage Breakdown

Size OD down ~0.125" per stage for sliding fit. Add 1–2" to inner tubes for retention stops. Use 1/16" wall 6061-T6.

Electrical

Power budget, wire gauge, and battery sag.

Power Budget

Drive motor count

Drive avg A/motor

Other motor count

Other avg A/motor

RoboRIO + radio + misc (A)

Keep avg draw under 80A. Main breaker: 120A. Battery: 18Ah.

Wire & Battery

Current (A)

Run length (ft)

Peak current (A)

Int. resistance (mΩ)

Fresh battery: ~10–15 mΩ. Old battery: 20–40 mΩ. Brownout below 6.3V.

Gearing

Compound ratio and gear/sprocket center distance.

Compound Ratio

Input RPM

S1 driver teeth

S1 driven teeth

S2 driver

S2 driven

S3 driver

S3 driven

Center Distance

Type Spur gear (diametral pitch) Chain sprocket

Pitch 20 DP32 DP (common FRC) #25 chain (0.25" pitch)#35 chain (0.375")

Driver teeth

Driven teeth

32DP: C = (T1+T2)/(2×32). Adjust ±0.010" for backlash.

HTD-5 Belt Calculator

Belt length, center distance, teeth in mesh, and belt finder.

Belt Parameters 5mm pitch

Driver teeth

Driven teeth

Center distance (in)

Motor free RPM

Belt width 9 mm15 mm25 mm

HTD-5 = 5mm pitch, rounded tooth profile. Aim for ≥6 teeth in mesh to prevent skipping.

Belt Finder

Enter pulleys + desired center distance to find the nearest standard HTD-5 belt.

Driver teeth

Driven teeth

Desired center (in)

Projectile Shot

Ballistic trajectory — range, flight time, max height.

Launch speed (fps)

Launch angle (°)

Launch height (in)

Target height (in)

No air resistance modeled. Add 5–10% speed margin for foam game pieces.

Auto Drive Profile

Trapezoidal motion profile for autonomous path segments.

Distance (in)

Free speed (fps)

Acceleration (ft/s²)

Throttle limit (%)

Ramp up → cruise → ramp down. Short distances may never reach cruise speed.