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Harmonic Block Overhang and Toppling Lab: 2D Side View & Centre-of-Mass Margins

An exploration of the limits of static equilibrium through the side view of a stack of blocks, revealing the intricate balance between overhang and stability.

mysimulator teamUpdated June 2026≈ 3 min read▶ Open the simulation

What is Harmonic Block Overhang?

Harmonic block overhang refers to the maximum distance a stack of blocks can extend beyond its support without toppling. This concept is rooted in static equilibrium, where each level of the stack must maintain balance with respect to its center of mass.

The harmonic series governs this phenomenon: for n blocks, the maximum overhang possible is approximately H(n)/2, where H(n) is the nth harmonic number.

Why Does Overhang Matter?

Understanding block overhang and toppling is crucial in various fields such as construction, engineering, and even everyday activities like stacking books or building structures.

The principles of static equilibrium demonstrated by the harmonic series have applications ranging from architectural design to robotics and mechanical systems.

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Centre-of-Mass Margins and Stability

In this simulation, the centre-of-mass (COM) of each sub-stack is plotted against its support. The COM margin represents how far the COM can extend beyond the support before toppling occurs.

By visualizing these margins, one can better understand the delicate balance required to achieve maximum overhang without causing the stack to topple.

Toppling Animation and Bisection

The simulation includes a rigid-body toppling animation that demonstrates what happens when the COM margin exceeds its limit. This visual aid helps in grasping the dynamic nature of stability.

Bisection is used to check if the overhang curve H(n)/2 holds true, providing a practical method for verifying theoretical predictions with real-world observations.

Frequently asked questions

How does increasing the number of blocks affect the maximum overhang?

Increasing the number of blocks allows for a greater harmonic series sum, which in turn increases the potential maximum overhang. However, each additional block requires more precise placement to maintain stability.

What is the significance of the H(n)/2 formula in this context?

The H(n)/2 formula represents the theoretical limit for the maximum overhang achievable with n blocks. It shows that while the overhang increases, it does so at a decreasing rate.

Can the simulation be used to design real-world structures?

While the simulation provides valuable insights into static equilibrium and stability, direct application in designing real-world structures requires additional considerations such as material properties and dynamic forces.

How does this lab relate to other physics concepts like torque?

The principles of torque are fundamental to understanding block overhang. The torque about the support point must be zero for a stack to remain in static equilibrium, which is directly related to the position of the centre of mass.

Try it live

Everything above runs in your browser — open Harmonic Block Overhang and Toppling Lab — 2D Side View & Centre-of-Mass Margins and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.

▶ Open Harmonic Block Overhang and Toppling Lab — 2D Side View & Centre-of-Mass Margins simulation

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