Inline Pressure Sensor
Inline Pressure Sensor for high pressure and alcohols
Authors: Bao Nguyen
Affiliations: Oregon State University and OPEnS Lab
Contact email: [email protected]
The first target when choosing a liquid media pressure sensor for the eDNA was being able to handle alcohol in high concentration. The second consideration is the pressure sensor casing (if there is one) would need to be easy to manufacture in the OpenSlab scale. The third consideration is the max pressure that the sensor read is above 15 PSI.
The first pressure sensor was suggested for the eDNA by the lab was the Non-Newtonian developed by Manuel and Luke. Detail about their publication can be found here. The design, use the MS5803-02BA SMD sensor that has up to 24 bits ADC which very accurate in eDNA concern. The pressure casing was printed out of resin, which also has a very high resolution for a watertight fit.
The major drawback of this Non-Newtonian pressure sensor module is the casing material itself. All the resin that is sold by Form-Lab, the SLA printer manufacturer, cannot handle alcohol for a long period of time. The structural integrity of the print will degrade, the part will get swollen up and soften. Different printing material was tried with FDM printer using ASA and nylon, but the quality is not enough for the watertight device under pressure. Moreover, the pressure sensor range of 4.35PSI ~ 15.95PSI is absolute. With 1.0 atm = 14.70 psi, the sensor is only useful to read up to 1.25 PSI gauge pressure in the tubing, below the function target for the eDNA (15PSI).
