Timothy Pan Portfolio

ZERO

'Hero' Combat Robot
Advanced Robotics @ UW 2025
Turret Base & Armor by Timothy Pan

Robomaster is an international combat robotics competition played by universities worldwide. The game is similar to paintball- robots shoot projectiles at each other, aiming for target armor panels to deal damage and score points.

Advanced Robotics at the University of Washington is a top team in the North American league, being the reigning champion for four years consecutively. We make the entire robot custom in-house using industry standard practices including SLS printing, waterjet & CNC machining, carbon fiber layup, and even electronics and circuit boards.

Background
The ‘Hero’ robot shoots a 42mm (golf ball sized) projectile that does ten times as much damage as the standard marble sized ammunition in the game system. However, the added weight of the 42mm storage and the increased complexity of the feeding system create unique challenges, as well as restrictions on power draw and movement speed.

I designed, fabricated, and implemented the ‘Turret Base’ subsystem that serves the crucial function of allowing the turret to yaw atop the chassis as well as serving as the access hatch to the 42mm magazine. Additionally I designed the armored covers that protect its internal electronics. These were an especially attractive assignment for an industrial designer due to them being the primary form of user interaction with the machine as well as giving it a designed silhouette.

Background
The ‘Hero’ robot shoots a 42mm (golf ball sized) projectile that does ten times as much damage as the standard marble sized ammunition in the …See More

DEVELOPMENT PROCESS

Design Objectives: Turret Base

Design Objectives: Armor Plating

Manufacturing

Iteration

Feature Showcase

Conclusion

DEVELOPMENT PROCESS

Design Objectives: Turret Base

Design Objectives: Armor Plating

Manufacturing

Iteration

Feature Showcase

Conclusion

Turret Base
Design Objectives:

> Support/Spin Turret

> Integrate Upgraded Planetary Motor

> Integrate Encoder

> Provide Access to 42mm in Storage

Preformed using pulley system

More powerful DJI M3508 for reactive yaw

Necessary because of backlash from planetary motor

Simple and passive

Armored Covers
Design Objectives:

> Protect Electronics
>Quickly Removable
>Attractive Silhouette

Tested various materials - utilized ABS sheet

Solved using automotive cover pins on each corner

Shaped to be sleek and deflective

MANUFACTURING

Machining

Many of our aluminum components are formed on the CNC mill- either straight from stock or from the waterjet. Parts are then deburred, polished and tapped by hand.

Processes Used:
>Water jet aluminum

>CNC Machining

>3D Printing (FTM & SLS)

>Laser cut panels

Machining

Many of our aluminum components are formed on the CNC mill- either straight from stock or from the waterjet. Parts are then deburred, polished and tapped by hand.

Assembly
Assembly following the CAD was a tiring but fulfilling process. Our robot has over a thousand individual components, including fasteners which all needed to be done by hand. Wiring was a similar stressful process as incorrect wiring and cable management could result in signal loss or hardware damage.

Assembly
Assembly following the CAD was a tiring but fulfilling process. Our robot has over a thousand individual components, including

ITERATION

Yaw Slipping Issues
The monstrously powerful RM3508 tore through my aluminum shaft extender and 3-D printed encoder when under high load, so left with no option, we remachined the entire motor shaft and installed a roll pin, which resolved the issues.

Through this experience I learned the importance of doing thorough testing before implementing any crucial mechanisms- the entire remachining and reinstallation project was extremely stressful and needed to be completed on very short notice due to deadlines.

Yaw Slipping Issues
The monstrously powerful RM3508 tore through my aluminum shaft extender and 3-D printed encoder when under high load, so left with no

FEATURES

3508 and Pulley

The powerful DJI RM3508 is our motor of choice for the yaw simply because of its size to power ratio. A 1:1 pulley ratio enables accurate turret odometry.

Encoder

Due to the gear backlash through the planetary gearbox of the 3508, an additional through bore encoder was necessary for accurate odometry. This encoder is developed by our in-house hardware team.

Magazine Cover
A 3-D printed cover lip provides an ergonomic fingerhold for pulling off the magazine covers while retaining a low profile.

Magazine Funnel
Guiding funnels make it easier for the human operator to replace the magazine covers during the high-intensity competition situation.

Magnetic Locking
When replaced, the magazine covers magnetically stay in place while the robot spins or is engaged in combat.

Bearing Clamp
The bearing clamp has a hole for cables coming from the slip ring in the firing system up to the turret and the electronics there.

UX for Debugging
All onboard interfaces for software debugging are deliberately located together and accessible with the covers on.

CONCLUSION

What did I learn?

The creation of this year’s Hero certainly did not go as smoothly as it may seem from just these pictures and renders. We were constantly fighting deadlines, patching mechanical problems, and working side by side with our electronics development and software team endless nights trying to patch issues last minute.

Although many things went wrong, including the problem with the yaw motor shearing, I am glad to say that we were able to work through our problems together and all of the original design intentions about accessible electronics and the easily removable covers were retained.

Without the help of my friends and upperclassmen guiding me, I certainly would not have
I gained a lot of valuable structural and engineering knowledge from working on the yaw system- and have taken my experience to work on the yaw mechanism inside the most complex robot we field- the two headed autonomous sentry.