My first science fair project on the subject studied the effect of changing the physical manufacturing parameters on the bending angle. For this, I fabricated tubes in two sets; one in which the circumferential width of the ablated region was varied, and one in which the depth of ablation was varied. Then I connected these components to a syringe pump and measured the bend angle achieved by the component in degrees. The results are shown to the right (below on mobile).

As hypothesized, increasing the depth of ablation increased the bend angle until a point at which instabilities occurred, because there was greater inflation asymmetry.

Also as hypothesized, increasing the circumferential width of ablation increased then decreased the bend angle, because the asymmetry first increased, then decreased. 

For my senior year science fair project, I continued the previous year's study, but with the primary focus of understanding instability behavior, a phenomena that I observed but was unable to properly study. I improved my experimental setup with a pressure sensor.

Here, the only fabrication parameter I changed was the depth of engrave, as I knew from the previous year that greater engrave depths typically led to more instabilities occurring.

As hypothesized, the instabilities that occurred were visible in the pressure data, sometimes showing up as brief plateaus, decreases, or bumps.

Also as hypothesized, tubes that were ablated deeper displayed instability behavior at lower pressure than those with shallower ablation.

Other takeaways included:

These components have highly reproducible instability behavior (as measured over ten inflation/deflation cycles), which is good news from an application/industrial perspective.

Although instabilities can be volatile, they can be used to operate a soft actuator very quickly and efficiently over a wide range of motion with little change in pressure.

I am currently continuing my research on laser-fabricated soft actuators at Carnegie Mellon University, working with Professors Rahul Panat and Trevor Jones in the Department of Mechanical Engineering.