Competition Strategy

Onyx completes the mission sequence of  Gate, Slalom, Bins, Torpedoes, Octagon, inter-sub communication, and Return Home while simultaneously, Græy completes Coin Toss, Gate, Style Point, and Return Home. By coordinating Onyx and Græy, they complete missions sequenced together in order to achieve inter-vehicle communication points. This setup provides a platform for inter-vehicle communication points and maximizes the time bonus points. We aim to enhance our navigation capabilities by refining our approach beyond dead reckoning to incorporate computer vision (CV) and station keeping. The general mission area is based on observations of the competition layout, similar to real-world mission planning, utilizing geographic features, and then using CV to fine-tune the final approach. 

Græy will pass through, save the gate location on an internal map, station hold while Onyx completes its mission sequence, and afterwards return to the Gate to roll two revolutions for style points. 

Operating two vehicles has proven to be difficult at the competitions. To mitigate future issues, the team will prioritize practicing with two subs during testing.

Coin Flip is performed first due to its simplicity. We will use a coin flip to randomize Græy’s starting orientation. Græy will submerge and yaw to face the gate using the VectorNav Inertial Measurement Unit (IMU),  and go through either side of the gate.

The gate mission is a prerequisite for both AUVs to perform further mission tasks. We aim for Disruptive capabilities this year through random role assignment via a coin flip. Our strategy is to have two mission sequences prepared for Search & Rescue or Survey & Repair. After the coin flip, the corresponding sequence for each role assignment is loaded. Each AUV utilizes CV via the forward camera to detect the assigned image and pass under it. 

Once through the Gate, Onyx localizes, adjusting depth to level and heading to center the pipes. Approaching the red pipe, Onyx will utilize the front-facing OAK-D camera to reach it within a set distance, move laterally, and then forward until the next red pipe is detected, repeating the process on the same side of the Slalom, achieving Advanced capabilities. Based on a pre-loaded mission map manually generated by the team, after timed failure of detection, Onyx will utilize waypoints to localize within a specified distance to the red pipe, looping the detection to proceed. 

Due to the high points and low risk, Surfacing is the fourth priority. Once Onyx navigates and localizes, it will use the front camera to approach the Octagon. The bottom camera centers, then Onyx yaws to face the corresponding icon and surfaces.

The long-distance navigation demonstrated for surfacing can be applied to return to the starting gate. Past the Slalom, Græy will localize, enabling station-keeping and waiting. Once finished, Onyx continuously sends signals until Græy responds with an acknowledgment packet that will be physically signified through light-emitting diode (LED) lights. Græy returns through the gate, performing her roll maneuver at the end to mitigate navigation disruptions. Onyx will stop sending signals and proceed to Return Home, utilizing the saved location from Græy, and Græy will Return Home to signal the completion of the run. 

For the Bins’ mission, Onyx will utilize the forward camera to approach the pipeline for the bins. Onyx will detect the light and navigate to the light, interacting with the magnetic detector to turn off the light. Proceeding, the bottom-facing camera then deciphers the image of the closest bin. If the assigned image is not detected, the forward camera navigates to the next bin, ascending in order for the bottom camera to view the image. After locking onto the bin, Onyx will account for the offset of the dropper from the camera, locking its station hold and dropping a marker into the bin. Onyx continues down the path until both marker droppers are in the corresponding bins. 

Torpedoes mission demands more precision compared to Bins. After localizing, Onyx notes its position, saving the location for station hold. After the target is centered in the camera, an offset is applied to center it on the launcher. Based on this procedure, Onyx will first fire a torpedo through the larger opening (🔥 🩸), then align and fire through the smaller opening (🚒 🚑).

The Octagon-Resupply mission requires localizing, identifying, grabbing, and releasing objects. Using its bottom-facing camera to localize and identify each item, Onyx’s gripper will supply the item, surface with the item, then face the correct role image based on the number of items, and descend to depth and release each in its respective bin. After completion, Onyx will yaw the same number of revolutions as items in the bins.