Flex Controlled Air Powered Gripper

About the project

A silicone air powered gripper controlled with a flex sensor glove.

Project info

Difficulty: Moderate

Platforms: AdafruitArduinoSeeed Studio

Estimated time: 6 hours

License: GNU General Public License, version 3 or later (GPL3+)

Items used in this project

Hardware components

Seeed Studio Grove - 2-Channel SPDT Relay Seeed Studio Grove - 2-Channel SPDT Relay I used 7 individual relays. x 3
Adafruit nOOds- Flexible LED Filament Adafruit nOOds- Flexible LED Filament x 1
coin cell holder coin cell holder x 1
Arduino Nano 33 BLE Sense Arduino Nano 33 BLE Sense x 2
Long flex sensor Long flex sensor x 1
Ecoflex 00-30 Ecoflex 00-30 x 1
Adafruit Air tube Adafruit Air tube x 1
Adafruit Air valve Adafruit Air valve x 3
Adafruit Air pump Adafruit Air pump x 3

View all

Hand tools and fabrication machines

3D Printer (generic) 3D Printer (generic) x 1
Soldering iron (generic) Soldering iron (generic) x 1


My project is a silicone gripper controlled with a flex sensor connected to my hand. When I close my hand the arduino nano 33 ble sense connected to the flex sensor sends a message to another nano 33 ble sense, the 2nd nano is connected to 7 relays. Each relay is connected to an air pump/valve (3 air pumps & 3 air valves), the final relay controls the nOOds green LED.

The silicone "fingers" are made of EcoFlex 00-30. I casted them using two 3D-printed molds, a top & bottom, which later is connected together using some eco-flex (also inserted an air tube in-between the two parts with a little bit of ecoflex to make sure it sticks).

Schematics, diagrams and documents

Transmitter _schematic

CAD, enclosures and custom parts

Base & top

Feed the air tubes through the holes & super glue the 3 fingers to each side. Super glue the top on the base.

Go to download


Glove made 3d printed out of tpu. Super glue flex sensor & electronics.

Go to download

Finger silicone molds

This makes the top & bottom of a silicone finger which you connect together with some silicone. The circular designs goes on the outside, the linear design goes on the inside.

Go to download



The transmitter code, arduino nano 33 BE sense with a flex sensor sends msg via BLE to another arduino.


Receiver code, controls the relays connected to the 3 air pumps/3 air valves plus the nOOds LED.


Photo of blight3d28


Hi, I'm Computer Scientist, love robotics & programming.


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