PhysSandbox
Classical MechanicsWaves & SoundElectricity & MagnetismOptics & LightGravity & OrbitsLabs
🌙Astronomy & The Sky🌡️Thermodynamics🌍Biophysics, Fluids & Geoscience📐Math Visualization🔧Engineering🧪Chemistry

More from Classical Mechanics

Other simulators in this category — or see all 85.

View category →
NewSchool

Spring Pendulum

2D elastic pendulum: swing and spring stretch together — energy swaps between modes; try chaotic-looking presets.

Launch Simulator
NewSchool

Bridge Resonance (1-D mode)

Damped modal oscillator with harmonic drive: sweep ω near √(k/m) — presets for cadence-like and low-ζ peaks.

Launch Simulator
NewSchool

Rising Bubble (Archimedes)

Ideal-gas bubble expands as it rises (p = p_atm + ρgy); buoyancy vs weight + Stokes drag — depth and velocity graphs.

Launch Simulator
NewSchool

Belt Drive & Slip

Two pulleys: tension difference limited by μ and wrap θ (e^{μθ}); load torque vs τ_max and simple slip on ω₂.

Launch Simulator
School

Free Fall

Drop objects of different masses with optional air resistance. Prove Galileo right.

Launch Simulator
School

Uniform vs Accelerated Motion

Compare constant velocity and accelerating objects side by side.

Launch Simulator
PhysSandbox

Interactive physics, chemistry, and engineering simulators for students, teachers, and curious minds.

Physics

  • Classical Mechanics
  • Waves & Sound
  • Electricity & Magnetism

Science

  • Optics & Light
  • Gravity & Orbits
  • Astronomy & The Sky

More

  • Thermodynamics
  • Biophysics, Fluids & Geoscience
  • Math Visualization
  • Engineering
  • Chemistry

© 2026 PhysSandbox. Free interactive science simulators.

PrivacyTermsContact
Home/Classical Mechanics/Bicycle Stability (2D)

Bicycle Stability (2D)

This simulator integrates a small-angle roll equation for a side-view bicycle sketch: gravity applies an overturning torque about the rear contact, while a trail-like term (∝ v²) models how steering geometry couples lean to a restoring moment, and an optional gyroscopic term scales with wheel spin Iω² ∝ (v/R)². It is a teaching cartoon, not a full Whipple–Carvallo model.

Who it's for: Intro mechanics and conceptual vehicle dynamics; comparing when gyroscopic effects matter versus geometric trail.

Key terms

  • caster / trail
  • gyroscopic moment
  • roll angle
  • critical speed
  • small-angle stability
4.5 m/s
52 mm
0.34 m
2.2 kg
0.28 m
82 kg
12 kg·m²
0.85 N·m·s/rad
6 °
Wheel ω = v/R13.24 rad/s
Linear margin (restoring − gravity)45.3 N·m/rad
Sketch v for stability (small φ)4.11 m/s

Shortcuts

  • •Space — start
  • •R — pause & reset

How it works

Side-view caricature of bicycle roll: gravity tends to increase lean, while fork trail (caster) and spinning wheels add restoring torques that grow with speed. Real bicycles also weave and depend on rider input; this model isolates two textbook ingredients so you can see why a minimum speed helps and how trail and gyroscopic terms scale.

Key equations

Iφ̈ = mgh sin φ − β(v) v² φ − k_g I_w (v/R)² φ − cφ̇ (trail + gyro, small φ)

ω = v/R; larger trail and faster wheels raise the restoring stiffness at a given speed.

Frequently asked questions

Is this enough to explain a real bicycle staying up?
No. Real bicycles involve steer angle, frame compliance, tire slip, and rider control. Experiments show many bicycles can be self-stable in a speed window even with gyroscopic effects reduced, so trail and mass distribution matter a lot; this lab isolates two common textbook ingredients.