Performance Check 3
Date: 3/29/2023
Number of runs: 1
Reflection:
The goal of performance checkpoint three was to traverse the lower deck to the fueling station and flip a lever indicated by RPS. Bonus points were awarded for waiting 5 seconds before flipping the lever up, and for flipping the correct lever at all. As in previous checkpoints, the robot was to begin moving only once the starting light turned on. Our robot was able to perform these tasks during the official checkpoint, but only on the second official run and after many failed test runs prior. In the end, all of the points plus bonus points were awarded.
The main problem we experienced this week was navigating using RPS. Some of the issues may have been caused by placing the QR code lower than the recommended height (something we intend to fix in the coming checkpoints), though we believe they mostly stemmed from faulty navigation code. Namely, our analogues to the check_x, check_y, and check_heading routines from Exploration 3 either returned early or looped indefinitely and rarely brought the robot to the intended location. As the performance checkpoint approached and we were unable to isolate the bugs, we mitigated the RPS issues by using shaft encoding instead, which had been successful in previous checkpoints. Unfortunately, this greatly complicated our navigation path as we introduced frequent “stopping points” along the way for the robot to reorient itself against a wall and reset the encoder counts.
The mechanical design functioned as expected, a relatively “simple” flipping mechanism that could hit the fuel levers. This was made with a servo that spins a flap up and down, which was more budget-conscious and easier to maintain than our previous rack-pinion design. The strengths of the mechanical design include the micro-servo being used having enough power and torque to flip the levers without any strain. The reach of the lever also allows for easy flipping in both directions. Most of this design will be unchanged moving forward. The best improvement for our design would come from the addition of a piece above the servo-controlled lever that would enable completing luggage drop-off without a secondary mechanism. The goal is to use the servo to sandwich the luggage between these pieces and then drop the luggage; then move over to the fuel levers later in the run and act as efficiently as it has been.