# @stem_antics on Instagram

- **Type:** Video
- **Original URL:** https://www.instagram.com/p/DZs3atASiFN
- **Gondola URL:** https://gondola.cc/posts/66891679-stem-antics-instagram
- **Thumbnail:** https://img.gondola.cc/tr:w-,h-,fo-auto/postThumbnails/0b3dd7599e.jpg
- **Posted:** 2026-06-17T20:51:01.000+00:00
- **Account Owner:** Stem Antics (@stem_antics) — https://gondola.cc/stem_antics

## Caption

A solid block of silicone shouldn’t be able to pick up a ripe tomato, a raw egg, and a stack of loose paper without bruising, cracking, or tearing any of them. Rochu’s soft grippers do exactly that, and the trick is that they barely “decide” anything at all.

These are PneuNet actuators: pneumatic networks. Each finger is a strip of platinum-cure silicone moulded with a row of internal air chambers sitting on a thin, near-inextensible strain-limiting layer. Inflate the chambers and the top wall expands while the bottom refuses to stretch. That asymmetry has only one geometric resolution: the finger curls toward the stiff side.

A few things fall out of this that rigid grippers can’t touch:

	•	One air line, infinite shapes. The finger is underactuated. A single pressure input drives the whole bend, yet the contact line passively wraps to whatever it meets. No per-joint servo, no object model, no grasp planning.
	•	Force spreads, not spikes. A rigid jaw concentrates load at a few points (Hertzian contact stress). A compliant finger smears pressure across a large conforming patch, cutting peak stress by orders of magnitude. That is why the egg survives.
	•	The body does the math. The conforming is mechanical, not computed. This is morphological computation: control outsourced to material and geometry instead of a CPU.

Actuation pressures stay low, often 20 to 80 kPa, far under what would rupture the elastomer, and bend angle scales roughly linearly with pressure for a fixed chamber geometry. Change the silicone Shore hardness or the chamber wall thickness and you retune grip force without touching a line of code.

Intelligence you can mould instead of program.

#stemantics #softrobotics #robotics #engineering #automation

## Stats

- **Views:** 6,914
- **Likes:** 102
- **Shares:** 0
- **Comments:** 2

## Tags

automation, engineering, robotics, softrobotics, stemantics

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