Bottomed Core Lander

Project Summary

The bottomed core lander project objective was to develop a test fixture to acoustically evaluate a device under test (DUT). The project involved the design, analysis, and production of a sub-sea structure used to orient the DUT to be characterized acoustically relative to a receive array of hydrophones located on the structure. I designed the structure to support a 2000lb dead weight used to embed the DUT into the seafloor at a height of 11 feet with material thicknesses less than ¾” to satisfy acoustic shadowing requirements. I designed the structure to be manipulated by divers in near-zero-visibility conditions and at low ambient temperatures by making everything the divers engage with light, easy to grasp, and highly visible. I analyzed the stability of the structure by calculating the force and angle at which the structure would tip over and determined the structure was stable in the desired use case. I calculated the maximum stresses on the structure in the worst-case loading condition using hand calculations and FEA, and determined the hardware, weld sizes, and material sizes required to maintain a safety factor of 3. I analyzed the depth of embedment of the structure into the seafloor and determined the foot sizing to prevent embedment at the deployment location. I performed buckling analysis on the support trusses using FEA, and added guide wires at points with the highest chances of buckling. I determined hand winch sizes required based on applied torque and gear reduction available versus the lifted load. I also managed all material procurement and fabrication to include welding and assisted with the assembly. After assembly I executed load and proof testing to validate its structural integrity.

Implemented Skills

• CAD (PTC Creo)

• structural analysis using first principles hand calculations

• weldment design and analysis 

• finite element analysis using ANSYS

• buckling analysis using ANSYS

• Drawing generation following GD&T standards

• material selection for rugged environments

• proof testing

• winch selection

• bolted joint analysis

• buckling analysis

• design for assembly

• sensor integration and cable routing