Competition Strategy

This year, our approach focuses on deploying two AUVs—Onyx and Græy—to perform mission tasks concurrently. Dividing the mission set not only maximizes time bonus points, but also lays the groundwork for implementing inter-vehicle communication and exploring the principles of swarm robotics.

To enhance navigation accuracy, we are building beyond traditional dead reckoning and computer vision (CV) by introducing a refined localization system. Our approach integrates sensor fusion, combining data from a Doppler Velocity Log (DVL), barometer, and heading sensors such as a Fiber-Optic Gyroscope (FOG) and a high-performance Inertial Measurement Unit (IMU). The DVL provides precise tracking of translational movement, while heading sensors establish azimuth orientation. Using geographic features of the competition field, we will navigate coarsely to each mission zone, and rely on CV to fine-tune final positioning.

Tasks are distributed between the two AUVs to allow for maximum efficiency. Onyx is responsible for Gate, Bins, Beacon Localization, Torpedoes, and Octagon (Surfacing and Trash Cleanup). Meanwhile, Græy will complete Coin Toss, Gate, Slalom, Style, and Return Home. Throughout the mission sequence, Onyx and Græy will maintain inter-sub communication, sharing mission status and coordinating transitions.

Gate is the highest priority task, as it is a prerequisite for all other scoring missions. Each AUV uses forward-facing vision to detect and pass beneath the sawfish panel. The selected side of the gate is noted for Slalom navigation, while the specific fish passed beneath is logged for reference during Bins and Octagon.

Coin Toss is a simple but required task, performed by Græy. After a randomized orientation via coin flip, Græy uses the VectorNav IMU and OAK-D camera to yaw toward the gate and visually identify the sawfish panel. After passing through and storing the gate location, Græy proceeds to the Slalom task and later returns to complete the Style mission with two full revolutions. Onyx, aiming to conserve time, bypasses the coin toss and moves directly to Bins.

Slalom follows as the third priority. Græy applies an updated strategy based on our 2024 Buoy mission. It localizes near the pipes, aligns itself, and uses its forward USB camera to approach each red pipe. Græy adjusts laterally between gates and proceeds systematically through the course.

Octagon – Surfacing is prioritized for its simplicity. Onyx locates the Octagon using the front camera, then uses the bottom-facing camera to center itself before surfacing. Once aligned and facing the sawfish, Onyx completes the task by surfacing at the target location.

After completing Slalom, Græy prepares for Return Home. It localizes near the starting gate and performs the Style task (two revolutions). This maneuver is reserved for the end of its mission set to avoid introducing navigational errors mid-run. Græy then enters a standby mode, awaiting mission-completion confirmation from Onyx. Onyx sends repeated status packets until Græy successfully acknowledges receipt. Upon confirmation, Græy returns through the gate, and both AUVs perform a celebration yaw—a full clockwise and then counterclockwise spin.

In the Bins task, Onyx uses its forward camera to approach the structure, followed by precise alignment using the bottom-facing camera. After adjusting for the offset between the camera and marker dropper, Onyx releases two markers accurately into the bin.

The Torpedoes mission demands even greater precision. Onyx localizes, aligns visually with the sawfish hole, and fires the first torpedo. It then aligns with the reef shark and fires the second shot. Due to the offset between the camera and the torpedo launcher, offset aiming is applied to ensure accuracy.