This article was written by high school robotics students Emma Li, Vayun Mathur, and Tanisha Mehta.

Over the summer, Singapore American School's FIRST Robotics Competition (FRC) team 4817 persisted in their goal to program a successful swerve drive base. Using a swerve base allows for independent control of each individual wheel; each wheel can be oriented in different directions to have more flexibility and fluidity in robot movement. Think of it as sitting on a chair with wheels—you can move forward, diagonally, sideways, and practically in any direction; you can also spin the chair around. The swerve works in a similar way, except it’s powered, motorized, and more complex in creation. 

Previously, during the 2020–21 robotics season, the team had attempted to build and program a swerve drive base. They 3D printed the wheels and designed and built the modules themselves; however, there were a few complications that arose– the robot would occasionally skew off or rotate randomly. The team still wanted a working swerve drive before the new 2021–22 session. During the summer, a new attempt at swerve (this time with custom modules) was made.

As working in school was not possible due to construction, one of the programming and electronics leads brought the robot home and held weekly meetings for members to come over to wire and code the robot. The electronic and wiring process was a tedious one; it had to often be redone for management purposes. Sometimes, parts had to be replaced such as fuses, motor controllers, electronic components, and radios. However, with persistence, the electronics were finished. 

The next step challenge the team had to tackle was the code. Compared to the program for previous years, the swerve code was significantly more complicated– the code had to have systems to control and observe every individual motor as well as to realign each wheel at deployment. 

The team also changed their controller type from a joystick to an Xbox controller, offering more control, more inputs, and easier manipulation– it was a vast improvement when it came to driving. It was extremely gratifying to see the robot drive smoothly across the floor, making figure eights and zigzag patterns. 

To make the robot movement more accurate, sensors were also required, for example, encoders were used to find the position of the wheels, a gyro was used to find the rotation of the robot, and limelight was used to align the robot to certain targets. With data inputs from these sensors, the robot became more precise and refined.

The final challenge to overcome was programming for the autonomous section of the competition—programming the robot to drive itself without user input. This was the more complex section of the code; instead of telling the robot to go straight, turn, go straight, and repeat, points were set, making a path for the robot to follow. This offers more efficient robot movement which can improve competition run times. Get a glimpse of what their robot can do.

This summer was a big milestone for the SAS robotics team. Not only is a new way of driving now possible, but the usage of more advanced code also means better competition code in the future. The robotics team plans to use swerve in their next competition robot, and is also using the current swerve bot for demonstration purposes—to show how cool robotics can be to the rest of the school!