Day 13: (Wed Mar 2, Week 7) Mid-Semester Integrative Review

Notes for 2022-03-02.

Assignments

Please fill in missing blog posts before Friday for the three-part exercise: Exercise: Mold Design Workshop (in multiple parts).

Agenda

Today will be devoted to a class-wide discussion of results. We will look at all prototype and documentation and brainstorm specific open questions to answer on our return from Spring Break.

Day 13 Discussion Summary

Some results of the discussion follow. These all represent possible design add process improvements which could help all projects.

1. Silicone bonding technique.

   • wider use of assembly jigs

   • possibility of bonding at 80% cure

   • bonding area design rules

   • lamination bonding (multi-layer flat sheets)

2. Silicone patching and repair technique.

   • puncture patching

   • cannula/needle insertion and retention

   • design of repair molds for fixturing and shaping patches

3. Soft actuator design.

   • better understanding of expansion chamber geometry

   • hybrid designs combining rigid and compliant elements

   • improved pneumatic port design, e.g. tubing, connectors

   • understanding impact of fluid choice (e.g. air vs water)

   • testing to failure

   • evaluation of fatigue failure

4. General design rules.

   • determine minimum thicknesses

   • elastomer bending and deformation analysis

   • microchannel geometry rules

   • features for assembling multi-part silicone structures

5. Mold design

   • constructing molds combining multiple 3D prints

   • surface finishing and sealing

   • possible acetone vapor finish

   • more experience with two-part molds, including semi-open and semi-planar

   • lost wax core technique

   • rotocasting thin shells (not currently needed)

6. Soft sensor design.

   • incorporating unported pressure sensors into elastomers

   • liquid conductor microchannel sensors (e.g. gallium)