The final project consists of a Cartesian machine capable of dispensing corrosive liquids, such as thinner, that can dissolve materials like polystyrene to create a subtractive fabrication technique with artistic finishes.
The following diagram demonstrates the knowledge applied at each stage of the project's conception, fabrication, and programming process.
It is a portable Cartesian device designed to eject various liquids with the intention of becoming a subtractive manufacturing method that does not rely on force, but rather uses chemical reaction as the agent for material removal.
The closest precedents of a portable CNC can probably be found in the Shaper Origin, a wood machining tool that, through a camera and screen, can guide the cutting path. However, there is no version that combines these properties of automation or assisted material subtraction with the ejection systems found in bioprinters. This is where the advantage of 'the Machine that Cries' comes into play.
"I will design a lightweight and portable casing for a transmission system based on smooth rods and belts, which enables the movement of a head coordinated by two stepper motors. Using a servo motor in a remote ejection system, it allows the liquid to be dispensed onto the surface.
I will use two Step Motor Drivers, two NEMA 17 stepper motors, an SG-20 servo motor, a Seeed XIAO, a 12V 10A power supply, a voltage regulator and four capacitors, along with a system of belts and smooth rods.
The Seeed XIAO microcontroller and some components, such as the fiberglass PCB base and pin headers, are part of the equipment provided by the university. The rest of the components were purchased privately.
Approximately $75 was spent on electronics, another $40 on mechanical parts, and around $25 on the fabrication of components, resulting in a total investment of $140.
The containers for electronic components, such as the printer case (which will be 3D printed) and the power supply enclosure (CNC machined), will be fabricated. Likewise, the machined plate that organizes the stepper motor drivers will also be manufactured by me.
Digital fabrication methods will be used, such as 3D printing, CNC machining in acrylic, and CNC machining for the fiberglass plate used in the electronics.
Extensive research must be conducted on the material aspect. The interaction between thinner and polystyrene is highly toxic and potentially polluting. While the mechanism is clever and highly expressive, it would be ideal to replace it with organic materials such as formic acid or similar substances applied to naturally sourced materials.
It is necessary to evaluate the coherence between the proposed subtractive manufacturing method and portability. Iterations can be made to improve performance.
The electronics and manufacturing parts are already completed; only the programming and testing stages remain
All the fabrication work (physical, tangible, so to speak) has been completed, but the programming part has only remained in the research phase, looking for a G-code firmware suitable for the memory space of the Seeed XIAO.
It is urgently necessary to determine which firmware is the most suitable. From what has been read so far, Tiny-G will be chosen; however, learning to coordinate servomotors with stepper motors for the project is still pending.
The project can be completed in its first iteration and open the field for experimentation with other automation methods for this subtractive manufacturing system.
his exercise has been very helpful for sharpening my knowledge of 3D modeling oriented toward mechanical systems. Additionally, I have learned a lot about the functioning of microcontrollers, from their design to their electrical operation. Finally, I have been exposed to less typical manufacturing methods which, although not used in this exercise, remain as possibilities for future iterations.
The project's movement scheme required the use of two motors to move the head in the X and Y directions, and a motor to displace the syringe plunger to eject the liquid. Based on this premise, two NEMA 17 stepper motors and a 3003 servo motor were chosen to perform the tasks. The voltage from a 12V/10A power source had to be regulated with a transistor to reduce it to 5V to operate the servo correctly.
The PCB machining process will be carried out using Aspire as the G-code processing software and will be executed on the Roland MDX-540 on a fiberglass board."
To incorporate the PCB into the design, its measurements are taken, and a housing is printed to hold it inside the machine.
Case Model
PCB Fusion File