The scope of this assignment was to build a machine that is functional and produces movements. Having the desire to experiment with different axes, that implies having motors that move the construction in different directions, the choice of building a universal plotting device came. This concept is not new and has been previously done during the Fab Academy years. Main inspiration for the project came from a former MIT graduate building an axis tool, A Machine that Makes. The aim was to supple the lab with a machine that draws and works and can be used by other students.
The functionality is straight forward. There are three axis X, Y, Z that by means of traveling and holding the tool, creates the drawing. Similar to laser cutter (only with one more axis) and to a 3D printer, the machine follows a path, using the g-code provided. Since g-code is read directly by the Universal Plotter and sent to the satshakit-grblthe intention was to use that at first in order to produce the drawings.
The intention is not create a perfect plotter, otherwise we just recreate an ink printer that is out there and is commonly used. The aim is to create a tool that draws digitally, with all it's imperfect lines, creating a 2D digital art using electronics only.
In order to better understand the common vision of the machine, as well as divide the tasks, we used sketches on paper and whiteboard. During this process we understood the benefits and drawbacks of our decisions as well as made constraints regarding the size and the area of drawing we want to produce.
As a result we were able to divide the tasks and act accordingly by designing our own parts.
Crytical part during the design and construction process was a clear communication and setting aside all the expectations. Having a clear discussion in terms of sizes and adjustments as well as final functionality.
In order to have a fast traveling axis, I decided to construct my bed are with the stepper motor attached to the traveling belt. It was also interesting to have a traveling belt incorporated with rod guide stepper motors and see what would result in terms of speed and accuracy.
Resulted pieces from the CNC.
Assembled pieces of the bed.
Mounting the barring.
Mounting the travel guide for the motor.
On the main frame.
To let the z platform move in y direction, the belt is squized between two plates.
The two rods are guided the z movement so it can moves stabily.
I used Solidworks to 3d CAD the model.
I made the 2d drawing in solidworks and then save it as an dxf file to laser cut it.
After I that I had to hammer them to press firt all the parts together.
Finally, I can attach them together to the whole machine.
Moving by hand
MP6500 Stepper Motor Driver Carriers PCB board
The board is design to simplify the connection of the stepper motor driver ti the Satsha GBRL board.Pololu
Pins MS1, MS2 and MS3 have to be connected in 5V in the MP6500 stepper motor driver carriers so that it offers 1/16 step microstepping.
This driver operates from 4.5V ti 35V and can diliver ip to approximately 1.5 A.
There is an on board timer poteniometer for setting the curent limit, turn it counter clockwise to decrease the current.
After finished milling the PCB, we need to drill the holes with the diameter of 0.9 mm and 1 mm.
Solder them all in the board and plug the pololu stepper motor driver.
The 3d CAD of cable holder.
Slicer for 3D pint the cable holders.
Manage all the cables with the 3d printed cable holders.
GBRL is a controller for CNC Milling which run on Atmega 328.
Download and install UGS Platform.
On the software use $$ command to get the current setting.Grbl v1.1 Commands
To change the setting just simply type the the parameter on the console for example "100 = 200" which set that x-axis travel resolution is 200 step/mm.
The Fab modules is used to generate the g-code.
Those are the parameters that I have used to draw with my machine.
This is the first try to draw on a notebook.
A2 drawing of a Barong.
Madala drawing from our machine.