Skip to content

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. Adriana Cabrera

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.
image image


Process and workflow

Vinyl / Ironic Fantasy

Ironically, we iron to inflate. Examples of Aeromorph project.

image

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.

class


Following Adriana's model, I made my own :

twisting

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.

twisting twisting


Unfortunately, my sinusoide was too thin to give a huge inflating result. It's working, but way far from what I expected.

Recto/verso


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

oxyds

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).

oxyds

Testing with the pump, it looks like a skin.


Sidenote april 2023 : alginate never really stops drying, so at this day my samples shrunk to a trickle.

dryed alginate


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.

button

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

products silicone

  • 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

different molds

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)

different molds

  • Wait until it's dry

different molds

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 equipment

waves

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 :

schema of the setup picture of the setup

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.

temperature

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. result

We change the travel distance setting. settings

Second test seems welded, but doesn't inflate. We keep the same settings but we change the material. result

Third test looked good but it didn't inflate. result

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 !

Fabrication files


Last update: 2023-05-10