12. Soft robotics¶
Research¶
Inspiration of alveoles :
Very inspiring work of Adriana. in different domains, such as the origami/folded papers activated by the thermosensitive thread. One of the subject I wish to develop later.
References & Inspiration¶
Lecture presentation with Lily Chambers :
"You can use mixed technics, and incorporate electronics – group work."
Very intrigued by the silicone inflatables molds and how they can be activated and become alive.
Process and workflow¶
Vinyl / Ironic Fantasy¶
Ironically, we iron to inflate. Examples of Aeromorph project.
Folding to unfold / Pleats please¶
Super easy way to start with vinyl : the "finger". Making pleats allows to get the form change when you inflate them. It gives a special 3D arrangement that deploys in line with the force of the pumping.
Following Adriana's model, I made my own :
I like the result, giving good inspirations for bigger or combinated pleats. Need to think about scotch to keep it sticked to the pump.
Asymmetrical inflatable¶
Wish to make an inflatable that deforms asymmetrically, following Saskia's work. I made it with vinyl and a strip of baking paper cut by hand in a sinusoidal shape coupled with a straight strip to get as close as possible to the comb shape.
Unfortunately, my sinusoide was too thin to give a huge inflating result. It's working, but way far from what I expected.
I made another try with the contreform of the paper comb shaped. Hard to manage the fact that sheets of vinyl have not the same thickness and flexibility depending on the colors even though they come from the same lot. I should have try with a thinner plastic sheet like freezer bags.
Alginate¶
- 100mL eau
- 3g alginate
- 5g glycérol
- Chlorure of calcium
Blue bladder¶
I don't like the neutral white of the alginate so I decided to add pigments (blue and purple oxyds) in it.
Following work of Gabriela to create a bladder-like bag. The aim is having a seamless object, with a tiny hole to insert the inflating pump.
The excess alginate ran down the bladder and freezed due to the calcium chloride already present (necessary to fix the exterior). I decided to keep this tail as it was fiber's muscles looking like.
The up-left picture is a different one, which worked less well than the other one (on the rest of the pictures).
Sidenote april 2023 : alginate never really stops drying, so at this day my samples shrunk to a trickle.
Blue button¶
Still same alginate mix, spraying it in button form, then injecting calcium chlorure inside with a thin needle at the end of the syringe so it creates very small caves inside that i can now inflate.
On all my samples, I really like the texture of alginate when it shrinks after calcium chlorure contact. It gives it a very skin look like, moreover the purple oxyd that made lumps, look like moles. I can't deny I'm fascinated again with biomaterials.
Aloe "time will tell / qui vivra"¶
Testing with a fresh plant
-
empty aloe stalk
-
inflate with the pump
-
note the results : it works !
Silicone¶
First steps of making the mold on Amandine's page.
Molding¶
- 100g silicone RTV 181
- 5g PRO R30
- Use gloves to manipulate silicone because it sticks to everything
- Cast in the mold
- Let dry 24 hour
- Gently unmold
Finishing¶
- 33g silicone RTV 181
- 1,6g PRO R30
- Mix together without energy to avoid bubbles
- Affix the top of the mold in it
- Spread a thin layer onto a flat surface
- Take it off slowy
- Put it on the prepared last layer (impregnated fabric with a thin layer of silicone)
- Wait until it's dry
How to clean silicone? Silly/conne¶
Because silicone is a very complicated-use material, follow those steps to be a as good as possible user :
- wait until it’s completely dry
- rub with fingers
- throw in a trashbin, not in the sink
Results¶
We had a weird result for our molds and they never dryed. Maybe we made some mistake in the proportions of the new silicone mix, if no, maybe it was the air being too wet. It's a fail. Here, you can see the right way to make it, by Adriana Cabrera.
Holiday's heat 1¶
With Laora and Amandine, we used the 3D printer to test heating the plastic film.
We wanted to "print" the waves we made during our week 10. We start from the former file to modify and adapt it to its new use.
Application¶
- Zmorph
- No filament
- Normal buse (3D printer)
- Illustrator
- Rhinoceros 3D
- Cura
- USB card adaptator for SD card
- Neoprene
- Plastic bag
- Parchment paper
1 - Preparation
We just need the nozzle to heat, so remove the filament.
In the menu : Maintenance > load filament > custom temperature
2 - Vectorization of the idea - by me
Rhino 3D interprets the export to .DXF with artifacts in the curves, problematic. At the time of extrusion there is a concern. This one produces a thin line. We encounter difficulties on the passage of the Illustrator file to Rhino. Magnify the tracings on Illustrator > decompose background contour. Had to transform this line in a solid so it can be interpreted in the right way by the printer. Export the right thickness (0,4mm), extrude (any height) and close the solid. We need to change the thickness of the path in Illustrator to the desired 0.4mm in Rhino 3D. We change the thickness of our path in Illustrator:
Preferences > units > mm
Steps in Illustrator :
On the left, the first alteration was to close the line, so air could be captured in and thinking at the same time of the entry for the pump. I did this appendice to join each side of the waves, but it was not symetrical and was not completely satisfiying. So, as we had these two waves nested one into the other, I let them being independant : more symetry and balance in the design (right).
3 - Export to open in Rhino3D - Laora's part
Steps in Rhino 3D :
4 - Go to Cura to have the final file for 3D printer (.stl) plus settings - Amandine's part
Steps in Cura :
5 - Set up 3D printer
Laora made a schema of the order of the layers :
6 - Calibration of the machine
Maintenance > calibration > manual calibration
Keep your finger on the emergency stop button in case the nozzle drops too low and breaks the glass. It happens quicker than you think.
Define the new Z0.
7 - Preheat the printer
Custom temperature > check that the parameters correspond to Cura = 190°C in this case.
Wait for the heat on the 3D printer to reach the desired temperature before starting but when it's good, start your work because it cools down quickly.
Pay attention where you put the clamps on the board, unwanted clash with the nozzle happens... often.
Results¶
First was not very conclusive, too fast and not enough heat. Also, we don't know why the printer made a first diagonale trace.
We change the travel distance setting.
Second test seems welded, but doesn't inflate. We keep the same settings but we change the material.
Third test looked good but it didn't inflate.
We streched it to test the resistance but it was really too fragile.
We raise the temperature to 250°C.
Last test is ok : same parameters in Cura but with trash bag (we don’t know the exact composition but we know it’s recycled). The weld is homogenous and solid, the air circulates throughout our sample !