1. Goal
Create a haircut helper to reduce the time of haircut
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Using a template trimmer to get hairstyle like the above state, the important part is the back of head since it’s hard to trim the hair in that area.
2. Prototype
Type I: a fixed template that cover the back head area
3. Implementation
3.1. Intuition
Material: soft alumni string to shape my head, since the precise model is not that important, a 4 by 4 grid is used
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Then we need to digitalize the curve. Using iPad and modeling software would be a good idea
Software:
- Tried Shapr3D, a good modeler, but require pricy subscription
- Freecad
3.2. Improvement
In the last design, although the overall idea is pretty simple and straightforward, but the implementation and modeling is too hard. So in this version, I would try to simplify the design
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this way, I separate the hair cut region into 2 part, program each part
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Tried control point and spline fit, doesn’t work well. That lead to my 2nd attempt, the log curve
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Well, it doesn’t do well either
Let try $x^3$
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Emm.. Still kind of werid.
Nevermind, lets do arc
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Circle never let me down
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Create the point cloud in open3d
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However, 3d printer can NOT print point cloud straight, we need to generate the face and compute the stl file. Meshlab can do this job by using ball pivoting algorithm
4. 3D Print
4.1. V1.0
- Problem: Can’t gather hair
- Solution: remove the horizontal line and mimic the normal comb
4.2. V1.1
- Problem: can’t control the hair clipper
- Solution: add guide for clipper