How hot does a walking pad belt get when you walk on it?

Another belt update. Sorry, this one is a bit technical and nerdy.

Today a member of the community came to the office to help me run some tests at the Office Walker weight limit. We recorded a few measurements with the pressure foil, with the goal of using them to calibrate the test rig.

Heat, not just pressure

Apart from the pressure on the belt, heat development might be an important factor.

After one of the tests on the test rig I realised that the belt was warm at the damaged spot even around five minutes after I stopped the rig. A hot belt could become softer and thus be damaged quickly. That seems to have happened on the test rig, as there were distinct imprints of two bearings.

What a person does to the belt

So today we also recorded the heat signature while he walked on it for 15 minutes.

This was super interesting. The temperature increased to 36 degrees within a few minutes and then appeared to saturate at around 39 degrees.

The belt material can withstand this temperature without problems, and the belt was without damage after this test. No dents, no imprints, as good as new.

On the test rig this same belt did not survive for five minutes.

Why 39 degrees is the number that matters

A belt is a polymer, and polymers soften as they warm. Below a certain temperature the material behaves elastically: press it and it springs back. Above it, the same pressure leaves a permanent dent.

So the question was never just how hard the bearings press. It is how hard they press while the material is soft.

39 degrees is barely above body temperature. It is the belt warming up the way anything warms up with friction, and it is well within what the material handles. That is why a person can walk on it all day and nothing happens.

What I check next

This is a very promising result. Next week I will record the heat signature of the belt on the test rig. If the temperature increases to 60 degrees or so, this theory would be confirmed.

And if it is confirmed, the belt was never the problem. The machine testing it was.

Thanks again to the community member who came in and spent an afternoon walking on a prototype so we could point a thermal camera at it. I really appreciate the effort.

Measuring the pressure · When the belt broke · The Office Walker