MECHANICAL TEAM
Mechanical members focus on designing, building, and testing the main hull, chassis, and external systems needed to run our robots. The vast majority of design work the team does is in SolidWorks and members utilize various machine shops on campus to realize projects. New members are accepted regardless of experience or academic year and are aided with lessons and one-on-one pairing. The team’s goal is to ensure that all members have the opportunity for hands-on experiences and learning that is often lacking in the traditional classroom.
About the Subteam
The majority of our design work is done in SolidWorks, the same CAD software that is taught in ME courses. In addition to design, we also use SolidWorks to run stress/strain and other simulations of our designs. We apply the fundamental principles of Mechanical & Aerospace Engineering, Materials Science, and ergonomic design to create the systems our robots need to run.
Members machine many of the parts needed for our designs. Whether drilling and tapping holes into a small plastic part or shaping a block of aluminum, members can get experience on the Bridgeport, lathe, CNC, waterjet and more! Additionally we often modify/create systems by hand, as seen in a picture at the bottom of the page, wrapping the coils for our Gauss-Gun Torpedo Launcher.
Everyone is welcome, regardless of skill level. Being part of the mechanical team will give you real design, manufacturing, and system analysis experience. Whether you are interested in design, mechanics, failure analysis, or robotics – you’ll find a fit with UWRT.
What has the Subteam been up to?
There have been a few major mechanical projects developed over the course of the 2024-2025 School Year crucial to the development of the team. Those of which include our newest robot, the S.S. Flip Barker (SSFB), updates to our main vehicle, Talos, and the Operator Box (Op Box).
S.S. Flip Barker
This year, UWRT has created a second AUV to bring to competition, a first in team history. Over the course of the year, the mechanical team worked hard to design and manufacture the S.S. Flip Barker (SSFB), putting their skills to use creating a new robot on a condensed timeline. The SSFB will hitch a ride on the primary AUV Talos to the Ocean Cleanup task, where its underwater drivetrain allows it to navigate the platform and collect trash using a rack and pinion claw. It completes a run by releasing a noodle on a winch, allowing it to surface while never leaving the ground. For more information check out the vehicles page!
The SSFB uses a unique ballasting feature to alter its own buoyancy- a system made of combined pneumatics and hydraulics controls the water level in two tanks mounted to the top of the AUV. When the robot needs more positive buoyancy, it can flood the tanks with air from a compressed air tank, and if it needs to sink again, it can vent out the air so that water can fill those tanks. Three solenoids control the flow of air and water in the system. A key feature of the SSFB’s ballasting system is the regulator housing. Machined out of aluminum, this airtight and watertight housing contains an air pressure regulator for the AUV’s pneumatics system, allowing for a safe transition between the high and low pressure plumbing. A significant amount of time was put into ensuring the housing would be completely sealed, and it was designed to only have two distinct parts, the lid and the housing itself, separated by a silicon gasket. This design minimized possible points of failure for the seal, allowing it to act as a junction box for some of the SSFB’s electronics as well, and a container for a Blue Robotics depth sensor. The housing also contains an led light strip, which acts as a visual indicator of the AUV’s status to the team. Protected by a leak sensor and blowoff valve in case of failure, the regulator housing is essential to maintaining the AUV’s depth and air pressure.
To provide an attachment point to Talos during transportation. A stainless steel plate was mounted onto the rear of SSFB, and a powerful solenoid electromagnet onto the back side of Talos. The electromagnet is capable of securely holding SSFB in place while travelling to the Ocean Cleanup Task, and can be remotely powered on and off, allowing for a diver to quickly and easily attach the AUVs together while underwater. Furthermore, Talos is capable of quickly detaching with SSFB at its desired location, saving valuable time without sacrificing stability while travelling in tandem with SSFB.
Talos
To enable downwards vision, UWRT designed a new internal cage which incorporates both a front facing (ZED X) and downwards facing (ZED X Mini) stereo camera. The electronics system maintains the previous used NVIDIA AGX Orin processor equipped with a CAN breakout board (electronics system communication), RS 422 breakout board (Fiber Optic Gyro interface) and GSML2 capture card (camera interface). A custom PCB distributes power throughout the cage and enables communication with the AUV’s sensor suite.
To mount in the cage into the AUV, new mounting rails clamp onto the hull and allow the cage to easily slide out of the AUV. These rails securely integrate leak sensors into the AUV and also provide mounting for the downwards facing camera. The cage interfaces with the DFC and the electronics stack via a custom designed spring-loaded connector. This allows the cage to be seamlessly inserted into the hull with no wires needing manually connected.
To enable UWRT’s custom IVC solution, an acoustic transmitter was designed and manufactured in house. The acoustic transmitter features a flooded core design which balances the water pressure on both sides of the transmission head allowing for consistent operation at depth. The magnetic core features samarium cobalt magnetics for corrosion resistance and a custom wound inductor. This solution undercuts the cost of on the market solutions, and the custom inductor allows for the device to be easily tuned.
One major mechanical challenge faced during and post RoboSub 2024 was preventing leaks from our servo housings’ dynamic seals. While the previous housings were effective in preventing flooding, small amounts of water would manage to leak into the main housing, resulting in a high risk of damaging servos and a constant requirement for maintenance to dry and replace absorbent material in the housing. This issue was promptly mitigated with the purchase of new Delrin servo housings that utilized a built-in mechanical seal. This new housing was highly effective in preventing both dynamic and static leaks, eliminating the risk of servo damage for our torpedo launcher. Given that the new servos were unable to rotate in a controlled manner past 270 degrees, a custom gearbox was designed to provide the servo a full range of controlled motion to interact with our torpedo launcher. The increased size and weight of the cantilever portion of the launcher resulted in a decrease in accuracy and stability, especially while moving. To account for the increased mass, a brace was developed to provide an additional point of contact to Talos, eliminating stability problems. In addition, the torpedoes and their interfaces were modified to host a guiding rod that dramatically increased their accuracy. Not only has the threat of water damage on our torpedo launcher’s servos been completely reduced, but they have been rendered more accurate and stable than ever before thanks to our efforts.
Operator Box (Op Box)
A substantial portion of the setup time for pool tests was dedicated to assembling the robot network. The original setup required three individual components (router, switch, and Wi-Fi gateway) to be unpacked and connected. The time spent to setup and then debug errors that occurred from incorrect connections cost precious time during pool tests and in the competition.
The Operator Box (Op Box) was designed to replace the existing Safety Stack drivers’ station for operating the robot. The team wanted to focus on improvements to the organization, storage, and capabilities to improve testing and dock time. The Op Box is an all-in-one solution to operating the robot. Built inside of a larger pelican case, it contains all the networking equipment and power infrastructure necessary for control of the submarine. Newly added is an internal battery and power supply from Ecoflow that enables operation independent from shore power. This has given the team the ability to evaluate the robot in locations such as lakes and rivers furthering our available testing time. Additionally, it allows us to bring up the robot in advance of a competition run, reducing dwell time and enhancing competition performance.
The system is controlled through a Reterminal 2 which allows for independent control of the robot without the need for an additional computer. The Reterminal through the built-in router also patches internet connections to all connected operators while simultaneously being connected to the robot.
Op Box features a built-in computer monitor in the lid to aid the software team members with additional workspace. A mounted power strip was added to give each member a place to plug in their laptops along with ethernet ports to direct connect to the robot. Finally, given its larger size, Op Box includes wheels and a telescoping handle to be easily transported to any location.
The OP Box project represents a significant advancement in the design and functionality of the driver’s station for UWRT’s robots. Through innovative design, careful planning, and rigorous testing, the project has successfully addressed the key needs of enhanced storage, improved organization, robust networking, and battery-powered mobility. The OP Box stands as a testament to the team’s dedication to excellence and their commitment to improving the tools and systems that support their operations.
