Wesleyan University · Jianna Shao · 2026

Curves in 3D Printing Steel

Predictive modeling of how robotic toolpath curvature influences metal deposition and bead geometry in Wire Arc Additive Manufacturing (WAAM).

Lab
Chang-Davidson Lab, Wesleyan
Process
WAAM · robotic MIG welding
Status
Paper in preparation

01 — The question

How does the shape of a robot's path change what it produces?

Two welded beads with bead width measured at the curve: 7.83 mm on a wider curve, 9.57 mm and 9.8 mm on tighter curves
Tight curvatures can create a noticeable change in bead width at the curve.

My research is done at Wesleyan University's Chang-Davidson Lab, which focuses on steel additive manufacturing using a MIG welding setup.

This project explored the relationship between programmed toolpaths and physical results, examining how changes in curvature and process parameters influence the final bead: a critical manufacturing consideration when translating design into physical objects.

02 — The experiment

Programming the path and welding the samples.

The robotic welding cell used for the experiments

I designed and tested curved robotic deposition paths across multiple combinations of curvature, wire feed rate, and travel speed.

The resulting deposits were measured and analyzed to understand how toolpath geometry affected bead width and height.

Skills used

  • Experimental design
  • Robotic arm programming
  • Wire arc additive manufacturing
  • Data collection (1,000+ bead measurements)
  • MATLAB data analysis
  • Non-linear regression modeling
  • Metallographic sample prep
  • Microscopy & microstructure analysis
  • Research communication

03 — The work

Robotic arm welding a curved path onto a steel plate
A still from video of the robotic arm welding the curves onto a steel plate.
A welded sample plate with six numbered curves
One of the many samples that were welded and then measured. 346 curves were measured in total.

04 — What I found

Curvature matters.

The study showed that toolpath curvature can substantially influence deposited bead geometry, particularly as curvature becomes smaller relative to the characteristic bead width.

Quantitative results are complete and being prepared for publication.

Presenting the research poster at the Wesleyan Summer Symposium

05 — Summer Science Symposium

Sharing the research

I presented this research at the Wesleyan University Summer Symposium, where my oral presentation received third place in the Spark Prize competition.

Research & recognition