Cast two silicone samples with mosquito netting embedded. Mesh is stuck well once cured, but not extremely thin and not quite inextensible either.
Cast samples of the best 20 micron wedges we have, one is silicone the other is polyurethane
Ordered super thin aluminum foil, .0005" (12.7 microns) thick.
Cast a new daughter mold out of task 3
Tues, July 8
The polyurethane microwedges and daughter mold from yesterday did not turn out well so I attempted to redo them today.
Listened to Aaron, Dan, and Noe give practice presentation and gave feedback
Super thin aluminum came in today. It doesn't necessarily appear super thing, but it is certainly inextensible (and conductive). I am also worried because it is a pattern on it that doesn't make it flat. Lastly, it comes in sheets that are hard to keep flat because they wrinkle so easily. I will try to epoxy some aluminum to silicone to see if it sticks and is thin.
Took pictures to document electroadhesion and backing layer prototypes.
Sprayed two full size samples of good wedges. These should work fine for doing an official trial on the test bed. Worked MUCH better than trying to spray lots of little ones.. this time I think the side with the wedges stayed clean and it was much faster.
Wed, July 9
Took more pictures for presentation on Friday
Made video of electroadhesion clamping force prototype for presentation on Friday. See attachment.
Made a stickybot toe-size flap prototype with mylar backed flaps
Pulled out polyurethane daughter mold, not successful.
Pulled out polyurethane microwedge sample for being carbon sprayed, successful.
Looked up ultra-thin metal wire meshes. Found 25 micron thick mesh, waiting for reply
Talked to Sanjay and Noe about testing electroadhesive microwedges on test bed. Realized we may need a frame so the conductive backing layer is floating so that it doesn't clamp down the wrong direction. Also decided we need significant plastic material to isolate high voltage.
Thurs, July 10
Tried to spin sylgard sample at 700rpm with D5. It came out of the mold but about 10% was lost to ripping. This will make it harder to spray without residue on the bottom. Wanted to do this to make a really thin back for conductive spray.
Worked on design for electroadhesive test set-up. We need to make a frame with special holes for the leads.
Used solidworks to mock up frame for lasercam.
Asked more questions about ultrathin mesh. We can get a free sample with 30$ of shipping (!) because it comes from China.
Friday, July 11
Spun sylgard silicone at 900rpm and 1000 rpm to see if it is possible to go super thin. There was moderate success. They did both come out of the mold, but with some ripping. It ripped especially easy at any imperfection on the wafer. Took a look at these thicknesses under microscope. It is hard to see the difference, but they certainly are thin. They are probably about 150 microns thick because the height of the wedges is a little longer than the thickness of the backing layer.
Did the safety training for the lab upstairs with the ultrasonic vibration machine.
Made adjustments to fix frame for backing layer on solidworks. Also got file ready for use with laser CAMM.