Week 18

Back

WEEK 18: APPLICATIONS AND IMPLICATIONS

I plan on making a laser cut arm structure, operated by servos and a 3D printed hand or grabbing device that will work as a soft robotics skeleton.

The arm design is a modified version of this 2017 final project which is itself based on the MeArm . You can find a step by step on how to build your own, here .

Materials

  • 1 x 3mm Acrylic sheet
  • 3 x SM-S2309S servo motor
  • 1 x AIRPO D2028B Pump, Vacuum pump motor
  • 14 x M3 nut
  • 16 x 10mm M3 screw
  • 4 x 10mm M3 screw
  • 1 x 40mm screw
  • 2 x ATtiny44
  • 4 x Sheets of PU + PET Film
  • 2 x ATtiny44
  • 1 x 10uF Capacitor
  • 1 x .1uF Capacitor
  • 1 x 22uF Capacitor
  • 2 x 10k Resistance
  • 1 x 0 Resistance
  • 1 x A4953 Motor driver
  • 2 x 5v Voltage Regulator
  • 3 x 2x2 Male Header
  • 3 x 2x3 Male Header
  • 1 x 20MHz Resonator
  • 2 x Buttons
  • 1 x soft, 3mm plastic tube with nuts and head.
  • 50 grams of Filaflex plastic for 3D printing

    • All the materials I was able to acquire at the FabLab.

    Costs should come around 50 euros or so, all together. I can’t be certain since most of the electronics components are cheapest when bought in quantity.

    There are two main parts: the arm and the hand.

    For the arm, I’ll be cutting the pieces from the 3mm acrylic and assemble it with the nuts, screws, servos and their respective board.

    The hand consist of a 3D printed, flexible skeleton that will be sealed into a PU + PET Film sheet by folding it and heating it at the sides, which the exception of the hole where the tube will go. It’s inner working is meant to mimic the movement of muscles by using oriented folds like in origami. So when the pump sucks the air out of the bag, the skeleton contracts in the desired shape to grab or lift things that have irregular shapes.

    After all the parts are printed, cut and assembled, I’ll need to connect and program the boards for each part. That is to say, program de servos for the movement of the hand and the board that controls the vacuum pump with its respective buttons.

    Once everything is working, it should be a great prototype to try out new shapes for flexible hands that can later be scaled for other purposes. The more hand models the better.

    All this should be done by next week, seeing as I only have to deal with some troubleshooting with the fabrication of the hands and the programming of the boards.