Refactoring The OpenSCAD Model

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Found a thin M3 nut (1.65 mm thick), these are used as locking nuts.

I already have 1.25 mm thick PTFE (6.0 mm diameter) M3 bushings.

So swap out the old components to see it I can use the 250 mm threaded rod that I already have.

Great, it works. Added the excess savings to the body width so I can install and remove the stepper motors after the body has been glued up.

I will have to check the actual widths of the nut and bushing before ordering the lasercut parts.

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Next is to replace the disk foot with an optimal foot. I can import a DXF into OpenSCAD for this.

Currently reworking the Optimisation Code to optimise the Foot at the same time as the Walker Geometry. Many hundreds of line of code to rework so it takes time.

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After, examining the the animation of the first optimal foot design, I noticed that the toe of the foot stabbed the floor on the return stroke!

So I fixed the minimum return stroke lift (5 mm) and practically destroyed the down foot stroke improvement:

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I could have just just used a point for the foot.

Still, a combine optimisation has potential to improve the down foot stroke.

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After several days of reworking the optimisation code, some preliminary results.

First was to use the current optimal model and the impact of the optimal foot:

The main improvement was the extension of the useful window to the rear (to the right) of the down stroke. To take advantage of this I need to recalculate the 120 degree window, and then optimise.

Here is the result of optimisation if the window is not moved and the other constaints are  removed:

Not ideal, as the non-custom foot curve (Y3) is worse but compensated by the custom foot.

 Still the oscillation of the down stroke has been reduce.

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Finished the the Optimisation code.

Best option seems to be taking the current optimisation and sliding the foot down window:

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The foot peak to peak "wobble" has been reduced from 0.94 mm to 0.48 mm:

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AlanX