Low-Cost Force Plate for Physics

 

Low-Cost Force Plate for Physics

Building a classroom force plate with load cells + HX711

Force plates are brilliant bits of kit – but commercial versions are far beyond most school and college budgets. The good news? With four load cells, an HX711 amplifier, and a microcontroller, you can build a surprisingly capable force plate for a fraction of the cost.

This DIY setup is ideal for A-Level Physics, GCSE enrichment, and first-year university labs, letting students move from abstract equations to real measured forces.

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🔧 What’s in the build?

• 4 × load cells (bathroom-scale style)

• HX711 24-bit ADC amplifier

• Arduino / ESP32

• Rigid base plate (plywood or aluminium)

• Simple calibration masses

The HX711 samples fast enough to capture short-duration forces, making it suitable for impulse, momentum change, and basic gait analysis.

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🧪 What can students investigate?

• Impulse:

  $$J = \int F \, dt$$
  

  Measure force–time graphs directly from jumps, hops, or ball impacts.

• Newton’s Second Law in dynamic situations

• Peak vs average force during landing

• Gait experiments: heel-strike vs forefoot landing

• Energy dissipation in soft vs hard landings

Suddenly, force isn’t just a number on paper – it’s a curve students can see, integrate, and argue about.

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🎓 Why it works so well in teaching

• Costs tens of pounds, not thousands

• Forces students to think about calibration, uncertainty, and sampling rate

• Bridges electronics, data logging, and mechanics

• Perfect for project work and NEA-style investigations

This is exactly the sort of apparatus that turns Physics from formula learning into experimental thinking.