Week 11: Soft robots

Create your own soft sensor or actuator using a pneumatic system.

Bending glove

A. WHAT

When I saw what can we do with the soft robotics, I remember the case of a friend that after at accident that gave him a spinal injury, can´t move his hands backwards. So, I try to create a soft glove using a pneumatic system, that can help him move his hands backwards because if he doesn't do it his muscles and joins atrophy. The idea is to integrate electronics and programming so the air pump works according to what he needs.

STEPS

1) CHOOSE PNEUMATIC SYSTEM: Following the examples of the Soft Robots Toolkit, I decide to try with the one using silicone, acetate and fabric.

2) DESIGN THE PARTS: Design the parts and mold in Rhino.

3) TRY THE SYSTEM WITH VINYL: Before using the silicone, I decide to try the design using vinyl that I cut with the laser cutter. I took the pieces, put soft paper in the middle and use the iron machine to glue everything. It works so I move on to the silicone.

4) 3D PRINT MOLD FOR SILICONE

5) LASER CUT: I cut the acetate, fabric and pieces for the glove.

6) MAKE THE SILICONE PIECE: After reading the instructions, we prepare everything and pur half of the mold with the silicone. After 3 hours, when it was completely cure, I put the acetate, more silicone and the fabric piece. I let it dry for 4 more hours. We try to put the molds on a oven to accelerate the process but the PLA mold started deforming (at 60ºC). We use EcoFlex silicone.

7) SILICONE + AIR: After removing the silicone from the mold, I put a needle connected to a

syringe and press it to see if it inflates. First, it wasn't even because the layers where not even, so it inflates more in one side. The good thing is that it bend in the direction I wanted.

8) MAKE NEW SILICONE PIECE: I made a second one to fix the uneven layers, and make it a little bit thinner.

9) JOIN SILICONE TO FABRIC FOR GLOVE

10) AIR PUMP + ARDUINO: We learn how to program the air pump using Arduino and some special components like solenoid valves and transistors but I didn`t have the time to add this system to the final silicone. For the first tests we pump the air with a syringe.