8. Soft robotics¶
This week we explored the world of soft robotics, a field inspired by nature and biomimicry—where movement, adaptability, and flexibility take center stage.
Unlike rigid machines, soft robots mimic the way plants grow, muscles contract, and organisms move in fluid, organic ways. The idea of designing something that feels alive and reactive really pushed me to think differently about motion and material behavior.
It was a refreshing shift in perspective—reminding me how softness, flexibility, and subtle motion can become powerful tools in both design and storytelling.
What is Biomimicry?¶
Biomimicry is the practice of learning from and emulating nature’s forms, processes, and systems to solve human challenges. It's about observing how living organisms move, adapt, and survive—and translating those insights into design.
For example, the dog paddle is a natural swimming motion that many animals instinctively use. We've mimicked this movement in swimming techniques, life-saving robots, and aquatic prosthetics—all inspired by how animals move efficiently in water.
Biomimicry shows us that nature often has the smartest solutions—we just have to pay attention.
Another great example of biomimicry is the octopus. Its soft, flexible body and intelligent movement have inspired the development of gripping mechanisms, tentacle-like actuators, and underwater soft robots. By mimicking how an octopus can wrap, hold, and adapt to different shapes, designers have created tools that are both gentle and precise—perfect for handling delicate objects or navigating tight spaces.
Nature as Inspiration¶
While researching for this week, I stumbled upon an incredible Instagram accountNature Inspiring that shares microscopic images of diatoms, insects, and biological textures. It's a stunning reminder that nature, at every scale, is a master of design.
The patterns, symmetry, and movement found in these tiny organisms offer endless inspiration—especially when thinking about how to build soft, responsive, and functional structures.
The main goal of this week was to explore the world of soft robotics—to experiment with materials, movements, and inflation systems that allow us to create responsive, flexible structures. Through hands-on prototyping and testing, we were encouraged to push the boundaries of what “robotics” can mean when it's no longer rigid, but soft, playful, and adaptive.
First Experiment: Silicone Casting¶
We followed this step-by-step process to explore silicone casting using EcoFlex 00-30, a soft, skin-safe silicone commonly used in soft robotics and prosthetics.
Step 1: Prepare your mold
We used existing molds made by previous Fabricademy students. Make sure the mold is clean, dry, and ready to go.
Step 2: Measure the silicone (1:1 ratio)
Carefully measure both parts (Part A and Part B) in a 1:1 ratio by weight.
Accuracy is super important—if the ratio is off, the result can get sticky, bubbly, or just ugly.
Step 3: Mix and pour
Stir the two components together until the mixture is fully blended, then pour slowly into the mold to avoid bubbles.
- Step 4: Let it cure
Leave it to cure for about 4 to 6 hours, or until it feels dry to the touch.
- Step 5: Cast a second thin layer
Mix a very small amount of silicone—2 grams total (1g from Part A and 1g from Part B).
Use a stick to gently apply it into the inflation channels and critical areas of the mold.
Pro Tip
Be careful not to block the air tunnels. If they’re sealed off, the robot won’t inflate—or worse, it might build pressure and burst during testing.
Inflation Method¶
For all my soft robotics experiments, I used either a manual handpump or a 3V electric pump, powered through a power supply.
This setup gave me better control over the airflow and pressure while testing each design.
⚠️ Note: Make sure you have full control over the power supply—too much pressure too fast can cause your soft robot to inflate unevenly or even explode.
Result¶
Soft Robotics Design Development and Fabrication¶
After exploring some references and getting inspired by nature, it's time to start designing my own molds!
The Maze Mold¶
Here’s how I created my first custom mold for soft robotics—a maze-like structure designed to test air flow and controlled inflation.
Step 1: Sketch the initial maze layout
I started by creating a simple maze-like pattern directly in Adobe Illustrator. I focused on building clean, continuous paths that could guide airflow and create interesting movement once inflated.
Step 2: Expand and edit in Illustrator
I imported the image into Adobe Illustrator, expanded it, and added an offset line to give the maze some structure and depth.
Step 3: Design the air tunnels
I carefully added tunnels for airflow, making sure the paths were clear and functional. Refining the tunnel width is key to ensuring good inflation performance later.
Step 4: Build the base and the rim
I designed two separate rim pieces: one for the bottom (where the maze sits) and one for the top/lid (to seal it shut).
⚠️ Note: All layers need to align perfectly—any mismatch could cause leakage or pressure loss during inflation.
Step 5: Prepare for laser cutting
Once the design was complete, I exported the files and set them up for laser cutting using 3mm acrylic.
I used Adobe Illustrator to finalize the cut file.
For detailed settings and prep, check my Circular Fashion Week!
Laser Cutting Settings
| Setting | Specification |
|---|---|
| Material Type | 3mm Acrylic |
| Laser Power | 80% |
| Cutting Speed | 20 mm/s |
Step 6: Glue the rim and bottom
Using super glue, I attached the rim to the base. At this point, you’ll have two mold parts: the bottom with the maze design and the top/lid that will seal everything in place.
Step 7: Prepare the silicone cast
Just like we discussed earlier in the documentation, prepare your EcoFlex 00-30 silicone mix in a 1:1 ratio—make sure it’s well mixed and bubble-free.
Step 8: (Optional) Add coloring for a marble effect
I added a bit of silicone dye to create a marbled finish. While the look was beautiful, the final result ended up a bit sticky, likely due to the type of dye used.
Recommendation: If you want to add color, make sure to use a silicone-compatible pigment, like Smooth-On's Silc Pig or other dyes specifically made for platinum-cure silicone.
To achieve the marble effect, you can gently swirl the dye into the mix (don’t overmix!) and pour it immediately into the mold.
Step 9: Glue the top mold layer
Once the silicone is fully cured and removed from the mold, glue the top lid onto the cast structure using super glue—just like before. Let it dry completely to seal everything together.
Step 10: Inject air and watch the magic happen!
Use a syringe and needle to inject air into the structure through the air channel. If everything’s sealed properly, you’ll start to see it inflate and move—it’s a super satisfying moment!