Difference between revisions of "Team:BostonU HW/Demonstrate"

MakerFluidics is an accessible, inexpensive microfluidic fabrication technique used to manufacture microfluidic chips. A user will use an SVG file to mill out both the control and flow layers of a microfluidic chip. Then he or she will use these 2 layers to sandwich a piece of PDMS and vacuum the chip to create a seal. Through Neptune, the user is encouraged to use this fabrication infrastructure to make their chip so that they may rapidly prototype many chips inexpensively for any iterations of their experiment and easily control their microfluidic system through the Neptune interface.

[Priya: Build & Assembly pages]

All of our STL files used for 3-D printing hardware infrastructure are parametric. If the user decides to use a different servo than that which Neptune recommends, he or she may simply enter a few measurements into the parameters listed at the top of the provided files and the designs will update automatically to reflect those changes.

Our software is designed to convert a mL amount to be dispensed into a PWM command to be sent to the arduino such that an even dispense rate is achieved for fluid movement through the microfluidic device. This conversion, however, is dependent on the specific servo/syringe combination the user has implemented. If the user decides to use a different servo/syringe setup than what is recommended by our system, he or she may still use our dispense conversion algorithm to control their system as it is also completely parametric.

Our Hardware system is highly adaptable for both small and large system requirements. Neptune is capable of running up to 200 servo/syringe combinations at once, fulfilling the need for the most demanding microfluidic system. This number is calculated by finding the bottleneck in data transfer from the computer to Arduino, and the transfer rate from Arduino to motor controller shield. Processing time in both the computer and Arduino are comparatively negligible.

Transfer to Arduino: 115,200 bits/second, 14,400 bytes/second Transfer to motor controller: standard mode of I2C: 100,000 bits/second, 12,500 bytes/second Bytes required for one command: 12

Therefore the maximum theoretical number of commands that can be sent at once is 12,500/12 = 1040. Including a safety margin of over 5x to ensure that all servo/syringe combinations can move 5x per second to ensure smooth motion all at once, Neptune’s set maximum is 200 servo/syringe combinations.

Neptune transforms the build area of a desktop CNC mill into that of an entire machine shop, and beyond. By milling square, modular components with pre-drilled holes for easy mounting Neptune can span a build area of one 4.2”x 4.2” square to hundreds of feet in any direction. This modularity, in addition to enabling huge build areas, allows for custom baseboard configurations to fix each project’s individual needs. The pre-drilled holes ensure proper component alignment and spacing, further adding to Neptune’s ease-of-use.