[WEEK09]Mechanical design

Link to the MTM global webpage of our team is here.

1.Brain storming

I discussed with my colleague (Saki Tomine) and tutor about what we meke in this assignment. We got some ideas, for example machine that...



Finally we decided to make a plotter with many pins that are pushed up in response to input data.

Product image


We think that this machine will lead to my final project and can also be applied to the data visualization activities that Saki is working on.

My final project

3D data visualization


2.Overview(Group assignment)

What we try to make is descrived here. (FabLab Kitakagaya page)

3.My work

3.1 Modeling a part of enclosure

The development view data of MTM kit was too large for our lazer cutter. So We modeled enclosure data from scratch.
I made bottom box data and Saki made a gantry and other parts. We used fusion 360 and proceeded with modeling while checking partner's works with each other in shered project folder.



Using these data, Saki cut out the cardboard, and attached a motor and shaft to make a mechanism to move in the X and Y directions.



Download

base_bottom.dxf: Download the file
base_front.dxf: Download the file
base_side.dxf: Download the file

3.2 Mechanism design to push up each pin.

In the following movie, pins are pushed up with fingers.
I tried to make mechanical design to do this operation.



I adopted a rack and pinion gear to it. A stepper motor rotate pinion gear and a shaft with rack gear is pushed up.
I drew a simple blueprint and tried to make first prototype with a cardboard and MDF. The purpose of this was to confirm the movement of the mechanism and the approximate size. So I had not designed accurately.



I used plug-in of inkscape to sketch rack and pinion gear.



After that, I completed design of each components with illustrator.



I modeled enclosure with Fusion 360.



I made each compornent with lazer cutter. The gears were made of MDF (5.5mm) and the enclosure made of cardboard (5.0mm).
I attached pinion gear to the shaft of stepper motor and assembled all components.



I rotated pinion gear manually, and checked how the rack gear moves. It wasn't smooth because I had not designed both gears accurately. And as the rack gear proceed up, it gradually tilts. Since the outline was confirmed, I will review the structure, calculate gear ratio and reflect it on the design.



At last, I attached this compornent to main body and checked movement and size.

Download

pinPusherGear.dxf: Download the file
pinPusherEnclosure.dxf: Download the file
gearTest_01.ai: Download the file