Gesture Controlled Soft Robot Tentacle

I wanted to make a simple soft robot. The soft robot has 3 chambers inflated by air pumps. Once made I created a small wrist mounted accelerometer (Arduino nano 33 ble sense), to control the movements of the tentacle in a fun way. The tentacle mold was made with a mixture of ecoflex 00-30 & dragonskin 10 (ecoflex 00-50 may be enough, so that the cost goes down..... but it wasn't tested). The air pumps & the the air valves are all controlled with one relay each (making that part of the code super simple). Code included at the bottom.

1) Two Arduino nano 33 ble sense boards

2) Three Adafruit air pumps Air Pump and Vacuum DC Motor - 4.5 V and 2.5 LPM [ZR370-02PM] : ID 4699 : $7.95 : Adafruit Industries, Unique & fun DIY electronics and kits

3) Adafruit silicone tube Silicone Tubing for Air Pumps and Valves - 3mm ID - 1 Meter Long : ID 4661 : $2.50 : Adafruit Industries, Unique & fun DIY electronics and kits

4) Six relays

5) Eco-flex 00-30 Amazon.com: Ecoflex 00-30 - Super-Soft, Addition Cure Silicone Rubber - Pint Unit

6) Dragonskin 10 Amazon.com: Dragon Skin 10 Medium - Addition Cure Silicone Rubber Compound - Pint Unit : Arts, Crafts & Sewing

7) Two Coin cell battery CR2032

8) Coin cell holder 2 x CR2032 Coin Cell Battery Holder - 6V output - On/Off switch : ID 783 : $1.95 : Adafruit Industries, Unique & fun DIY electronics and kits

9) Adafruit air valves 6V Air Valve with 2-pin JST PH Connector [FA0520E] : ID 4663 : $2.95 : Adafruit Industries, Unique & fun DIY electronics and kits

3D print silicone tentacle mold. Need to print both pieces (top & bottom pieces 3 times each). After, solder top and bottom piece together. Fit the 3 mold pieces together & screw them together. After, print the inner molds this is what forms the inner ridges in the silicone tentacle. Fit the sticks one by one in the triangle & solder them together in place.

Can't attach the "Inner design_mold_tentacle", download here --> Gesture controlled soft robot tentacle - Hackster.io

After you remove the molds. Print The base of the tentacle, solder the two pieces together. Once your silicone tentacle has been made, put some silicone on the 3 circles and press the tentacle together with the pla (or crazy glue, much faster). 3 small square holes in the cube are for you to feed the air tubes through. The bottom of the circular piece contains a small tube for you to connect the air tube to.

Code included.Put all the electronics together, every air pump & air valve is controlled by a relay (making that part of the code super simple). Print the watch case, you need a nano 33 ble without pins & a power source (I used 2-coin cell battery holder from adafruit) use small screws to hold everything to the 3d printed case. I used nylon straps for the wrist part. Download the Transmitter code to the nano 33 ble "watch", the other nano 33 ble will control the air pumps (the receiver).