Overview

For my senior design project, my three-man team was tasked to design a robot to clean heat exchangers and design a borescope attachment to help with pipe inspections. My roles were project manager, robot chassis subsystem lead, and floater to help any of the other subsystems. I was able to design a prototype robot in Solidworks and create the engineering drawings for manufacturing the prototype and help the other subsystems when necessary.

I used FEA to simulate loading conditions that the individual components will experience while the robot is in use. I was able to reduce the weight from 118 lbs of the first design down to 97 lbs, which is roughly 18 % of weight savings. I was able to achieve this by using smaller metal tubes for the telescoping leg while keeping the FOS above 10, per our advisor’s suggestion, and using thinner sheet metals for the housing.

I also spearheaded the creation of the 35+ page engineering document to send to the Pearl Harbor Shipyard machine shop to manufacture our prototype. I utilized GD&T to convey the clear intent of each drawing. I used true position, datum feature, angularity, and feature control frames in my drawings.

Lessons Learned

Initially, our prototype was supposed to be manufactured in-house at the base. But due to unforeseen circumstances at the shipyard, three months before the class was supposed to end, the base decided that they weren’t going to be able to manufacture our parts. The team did not fundraise any money because we were told that the shipyard will buy and manufacture everything for us so we could not buy the metal ourselves and machine it at our university’s machine shop. 

In the end, the project goal was changed three months before our final presentation. Instead of creating a prototype and testing it out, the team will just finish the electronics and coding section of our robot to prove that the concept of an autonomous heat exchanger cleaning robot was possible. A lesson I learned from this was that there should be redundancies put in place for everything, not just in the design. Fail safes for project funding should be considered just in case circumstances like what our team experienced happens again.