Microfluidics Design¶
The microfluidics chip design starts with constructing the design in 3DuF, then modifying and combining in Inkscape and Fusion 360 to meet the fabrication machines requirements.
3DuF¶
3DuF is a very practical website to make microfluidics design due to the various options it offers for the microfluidics chip. This website gives the user the chance to manipulate the type of bents (i.e. square or round), number of bents, number of inlet and outlet ports and to modify the size of the channels. The design made consisted of two inlet ports, one outlet port and rounded bents.
More details about 3DuF can be found in Zahra’s page here.
Inkscape¶
After obtaining the files from 3DuF, the design files were transferred to Inkscape to be combined and connected, as each part (i.e. ports and channels) are not connected when exported from 3DuF. Inkscape utilizes the union path command to connect the parts of the microfluidics chip together to end up with one piece which improves the fabrication quality and eases the understanding of the fabrication machines to the design. After completing the assembly, the file is exported as a DXF file for further usage.
In inkscape, the main two files to be imported are the ports and the channels as seen below:
After that, inkscape is launched and a new document is constructed:
When the new document is open, the channels of the microreactor are imported, followed by the importation of the ports that are specified in the preliminary design of the microreactor:
Make sure to import the files as editable objects for several reasons. Firstly, this will maintain the quality of the parts as it will not covert them into pixels and will keep the original vector format. Secondly, you will need to edit them in order to connect the parts together so that there are no problems faced in the fabrication part improving the quality of the procedure. Finally, you can size them and scale them up if needed to.
This is how the channels and the connecting tubes will look in inkscape:
Similarly, the ports are imported in inkscape yielding the following microreactor design:
Then, the union command is utilized to join the ports and channels as follows:
Similarly the other parts are connecting to each other:
The microreactor will look as follows after complete assembly:
After finishing the assembly of the parts, the file will be saved as a dxf file which is done as follows:
Fusion 360¶
Fusion 360 is utilized to convert the DXF file obtained from Inkscape to STL file. The DXF file is considered as a 2D file whereas the STL is a 3D file. This step is done to accommodate for the incompatibility of some fabrication machines like the CNC milling machine to accept DXF (i.e. 2D) files. In Fusion 360, the thickness of the PMMA sheet and the depth of the channels were specified.
Firstly, the dxf file obtained from Inkscape is opened in Fusion 360 as follows:
The dxf file will look as follows in Fusion 360:
After that, we create a sketch to make the PMMA board:
This PMMA board is extruded as per the thickness of the material at hand:
Then, the channels are extruded based on the specified depth of the channels:
The final design will look like this:
Finally, the design is exproted as an stl file for further utilization in the CNC milling machine:
Here will be shown the file and its status for the exportation as an stl file:
