2021 VEX World Championship Excellence Award

Posing With My Trophy and Winning Robot

Driven by a personal dream, in my freshman year I led the first ever Singapore American School team to qualify for the VEX Robotics World Championship and ultimately garnered the top Excellence Award. This 2021 win supercharged our after school program from it's inception in 2013 as a get-your-feet wet program with ~10 active members to a ~50-strong group of students highly committed to learning CAD, engineering and problem-solving skills while aiming for excellence.

2020-21 VEX Robotics Competition Game: Change Up

The goal of the VEX Change Up game was to collect, sort, and organize balls in hoops against competing teams. Each team designed and built unique robots, documented the process, and trained in driver and autonomous modes. For more details you can check out the game video.

Due to the COVID-19 pandemic, there were onerous lockdowns in Singapore, with restrictions on school activities and home visitations. These restrictions meant that I was at times only able to work alone or with 1 or 2 other team members (out of 10 teammates total).

The Process

Like most VEX teams, SAS traditionally built VRC bots with a direct hands-on approach. However because of lab time restrictions due to COVID-19, I decided to teach myself computer-aided design (CAD) during the summer prior to 9th grade as soon as the rules of the 2020-2021 VRC's game were announced.

In my 10-person team I was the team captain, lead designer, sole CADer, lead builder, lead documenter, and lead driver.

First Robot Iteration: Self-Taught CAD for a Streamlined Model

The First Robot Iteration CAD

By the end of that summer break, I had nearly finished my first ever CAD.

This design used a standard 4 motor tank drive. The general design was to have a storage system on a 4 bar linkage. A goliath intake would take in balls spinning in one direction and dump them out spinning in reverse. By using a 4 bar, the storage could be kept parallel to the ground while the arms brought it above the hoops. The guiding intake arms in the front of the bot was never CADed, since my team decided to abandon the design and move on to a more efficient iteration.

Second Robot Iteration: More Gears and An Original Ratchet Design

Taking inspiration from the general design circulating on YouTube at the time, I CADed a new robot with more features than the competition. The base design was a robot that could intake balls from the bottom and shoot them out the top. My introduction of ratchets allowed for the hogging of opponent's balls in a secondary storage. This is a unique design that I had not seen in competing robots.

The Second Robot Iteration CAD

A lot of thought went into the design of the ratcheting mechanisms. This design allowed the hogging of opponent balls while storing optimum number of scoring balls while keeping within the size and motor limitations.

Images of the Real Robot and Elements Changed after the CAD

As my team at this point consisted of inexperienced members, I led the team to build and fine-tune the bot, from rubber band tensioning, to fabrication of guiding hood that was absent in the CAD version.

We competed with this design at the VRC Singapore Regional. It performed as the best robot from Singapore American School, but failed to beat the opposing schools. This being my first year dabbling in VEX, our inexperience was a handicap.

My First Attempt at Building a Ratchet

While the ratchet design was a cool idea, it was unreliable and prone to jamming. Hence this design was ultimately abandoned.

VRC Worlds Qualification

We tried multiple routes to qualify for the VEX World Championship. Some team members fell away, but new ones would join. The final team was completely different from the early season team, with me as the one constant. Finally we qualified by winning the Encore Online Challenge. In the previous year I had led my VEX IQ Competition (VIQC) team to the VIQC World Championships, but that event was cancelled due to COVID-19. The Encore Online Challenge allowed competitors in this situation to compete for a Worlds ticket the following year.

Third Robot Iteration: A Perfect CAD Design

The 2021 VRC Worlds Competition was completely online, which triggered a change in the game rules. Without a physical opponent, there was no benefit to storing the opponent's balls. I redesigned a simpler and more efficient robot.

The Third Robot Iteration CAD

Some of the innovations include the incorporation of a complex X drive base allowing the robot to move and turn in all directions, a non-ratchet sorting mechanism, and a high precision shooting sytem for scoring goals. Most importantly I had now mastered designing on CAD and we were able to build the robot according to drawings without a need for fine-tuning modification.

The Third Robot Being Built to on the Field

The team pulled off some amazing feats in the lead up to Worlds. I CADed the entire design from start to finish in 5 days during school term. All of the robot's parts were fabricated in a single day. The robot was assembled in one and a half weeks and programmed to competition day. The best autonomous runs by SAS that season were made on this design. I practiced driving the robot every day for at least 6 hours in the remaining 2 weeks we had leading up to the world championship.

VRC World Championships: Excellence Award Win

The competition coincided with Singapore American School's final exam period, so it was an extremely stressful time. By this time, we had four core members left. Nevertheless, we pushed on. We presented our 415 page engineering notebook that showed our entire design process in detail. We then performed a few driver and autonomous runs live in front of the judges. We had managed to score more points in our best practice runs, but we still had a pretty good showing. (See the links at the bottom of this page.) All of this culminated in the big win!