Multimedia

A final design overview of the PVC and 3D printed enclosures. This video shows the assembled enclosures and their individual components. 

The final PVC enclosure, node support insert, and 3D printed enclosure (left to right). 

The assembled PVC enclosure. 

The assembled 3D printed enclosure. 

Results of the PVC and 3D printed enclosures during the initial marsh submersion test. The enclosures were left partially submerged in the Kendall-Frost Marsh Reserve for one week with humidity sensors for data collection. The maximum humidity reached in the 3D printed enclosure was 73% relative humidity and 72% for the 3D printed enclosure. 

A diagram of the ENTS node showing its different parts and their functions. 

A timelapse video of a Bambu X1 Carbon 3D printing the full base of the Hex design. This was printed using 7 perimeters and 40% infill. 

David deploying the PVC enclosure and Hex V5 enclosure at the Kendall-Frost Marsh Reserve. These were partially submerged for one week to collect long-term data on the enclosure's waterproofing performance.

An exploded view of the PVC enclosure CAD. This provides a visual of all components of the design (ex. cable glands, node insert) and shows that a maximum of four cable glands can be safely installed. 

An exploded view of the 3D printed enclosure CAD. This provides a visual of all components of the design (ex. O-Ring, cable glands) and shows that a variable number of cable glands can be installed by changing the STL file. 

Results of the 3D printed and PVC enclosures during the initial marsh submersion test. The enclosures were left partially submerged in the Kendall-Frost Marsh Reserve for 24 hours with humidity sensors for data collection. The maximum humidity reached in the 3D printed enclosure was 91% relative humidity and 67% for the PVC enclosure. This noted that the 3D printed enclosure had some leakage. Visual inspection led us to believe that the failure was caused by the screw-on mechanism, not the cable glands. 

Results of the 3D printed and PVC enclosures during the simulated marsh submersion test. The enclosures were left partially submerged in a container of mud and water for 24 hours with humidity sensors for data collection. The maximum humidity reached in the 3D printed enclosure was 63% relative humidity and 97% for the PVC enclosure. This noted that the PVC enclosure had major leakage. Visual inspection led us to believe that the failure was caused by user error; the dead cables used to fill the cable glands (shown below) were slightly too small to perform correctly. 

The Hex v4 enclosure. It had customized threading to optimize thread strength and resolution. Holes for cable glands were placed at the bottom of the enclosure to allow more more organized cable management and to improve the structure's overall strength. 

The PVC enclosure v2 configured for testing. Dead cables were used to ensure that if leakage occurred, there would be no electronic damage. 

Partial submersion tests conducted on 3D printed test samples. These tested the number of perimeters from 4-6 and the effects of different materials, such as silicone sealant and ASA filament. These samples were left in water for five weeks to observe if water seeped through the walls. 

A 3D printed mold made in order to hold the node securely using four bolts. It is pictured in the 3" PVC enclosure. It had a twist lock mechanism to ensure ease of access in the field. 

A top view of the mold in the PVC enclosure.

Leakage tests conducted on test samples. These tests were done to test different 3D printing parameters. The top four are made of PLA filament and test the use of sealant and number of perimeters. The bottom is made of ASA filament. These samples were left full of water for three weeks and weighed to see if the samples had any water seep through. 

The Hex design v2 enclosure. It used standard pipe threading for the screw-on mechanism. It also allowed for use of standard O-rings (65 mm ID) and had flat faces to allow for more cable connections. 

A CAD rendering of the PVC design. It is made up of a PVC tube, an endcap cemented on, a threaded adaptor cemented on, and a threaded cap that screws on. 

The first CAD rendering of the Hex v1 design. The top piece attaches to the bottom piece by threading, utilizing a screw-on design. 

The first 3D printed enclosure. It had two holes used for cable glands and was sealed by an O-ring and eight bolts.