This week saw us begin to implement some of the last minute design changes to our project. Firstly, the team was able to place orders for the structural materials as well as the new rods for the increased gantry length. In the back half of the week we were able to modify our gantry which allowed us to strategize how we wanted to attach the new, longer gantry to the prefabricated cart. Our current idea is to have a large piece of sheet metal that runs along the inside edge of the cart of the same height as the gantry. This piece of sheet metal will secure bolts which are fastened to the gantry to mitigate movement and vibrations. The sheet metal which is above the top of the cart will be supported by metal beams to ensure it stays upright. We plan to get an expert opinion on this structure from Ed at Techspark who may help in fabricating our design.
Additionally, we have made progress on the software pipeline. During the interim demo we had issues with the svg to gcode conversion. We have root caused the issue and have determined that the pdf to svg conversion is not always consistent between different pdfs. For example, the svg for images and text differs and our gcode conversion only currently works for some svg for images. Debugging this has been a work in progress and we are debating pivoting to other file types or trying to modify the pdf such as compressing it before converting it to svg. As the final deadline approaches the group may have to pivot to only having functionality for certain hand-selected files.
Finally, one of the comments we received from the teaching staff revolved around the speed of which the gantry draws. Currently small images can take substantial periods (4+ minutes). We look to remedy this by converting many “arc” drawing types to more “line” drawing types to increase the speed. This will have to get implemented after the svg to gcode is functioning on a more consistent basis.
Verification methods for subsystems are below:
- Website PDF to SVG: Upload PDFs with a variety of text, images, or both and view SVG output to determine effectiveness
- SVG to Gcode: Take a variety of SVG files and determine the Gcode output is viable for our system/
- Motor control: Use working Gcode files to evaluate motor precision and speed.
Validation methods:
- Run tests with a variety of pdfs with images, text, or both to determine effectiveness of the system.