16_MECHANICAL DESIGN, MACHINE DESIGN

josefinaPETRINI

This week was a group assignament, build modular machine parts including an end effector and program it. We started by ordering Cardboard CNC modular machines with its gestalt nodes from Nadya and watching some examples, but the scale of the modules were too short for our idea.

This a pizza cutter machine, which involves a linear and a rotational process.

The rotational mechanism consists in:

  • two laser cutted acrylic gears,
  • one bipolar stepper motor,
  • a mdf base with a 3d printed system of wheels.

    The linear axis instead works equal to the cardboard stages but it is 60cm long, so it will need

  • a couple of metal rails (2x700mm)
  • threaded rod (ΓΈ8mm x 700mm)
  • a 3d printed PLA box that will be holding the tool, in our case a blade.
  • Bearings (x4) for the box to slide through the rails
  • a spring to hold the blade
  • a Z coupler 3d printed PLA piece, to fix the threade rod to the motor
  • a bipolar stepper motor. Each motor will be controlled through a gestalt node and framework.

    For the base of the machine we used a laser-cut mdf platform.

    _PROCESS

    First fix one of the stepper motors to the mdf base and the acrylic gears on the upper side of the platform. Fix the gears with two nuts. After the gears we did a small laser-cut piece to hold the round base. So, the rotational system is done! be sure that the stepper motor cables are long enough to connect them to the gestalt node and you can be comfortable while doing the programming part.

    For the linear axis, first fix the motor to one of the side walls fo the wood platform, mind the thickness of the wood before fixing it.

    How to join the threaded rod to the stepper motor:

    In order to join the stepper motor with the threaded rod we 3d printed a Z coupler piece which is strong but flexible enough to hold the rod. Make sure to print the Z coupler horizontally, otherwise it wont be felxible!

  • How to fix the tool to the 3d printed box: We 3d printed a box that slides through two metal rails and bearings. This box is also attached to the threaded rod with nuts which make it move. Finally, the box also contains the blade fixed with a screw and a spring which gives force to the blade as it has to cut.

    _PROGRAMMING THE MACHINE

    In order to power the machine we did a fabnet that connected the 12v power supply to the gestalt nodes. This is the code for the pizza cutter!

    _WHAT I HAVE LEARNED

    Through this assignament I have learned how important is to work interdisciplinary, in the same way components get together to make a machine which can have multiple purposes. It has also been a good trigger to start working on the final project!

    Done by:

  • Pamela Chami
  • Alessandra Ferreira
  • Milena Orlandini
  • Mariona Aloy Ciller
  • Kalil Ventura