Conclusion:
This semester, our team had a goal of creating an automated water juggling mechanism that would transport water or other liquids from one cup to another using a closed-loop feedback system measuring the angles of the cups to determine the necessary motion to complete the task. While the cups we placed onto the mechanism were able to follow the desired and predetermined pathway, the motion was too harsh and forceful to the point where the links holding the cups hit the system and causes errors in the motion. We are able to manually control the motion to the desired speed and reactions, but additional steps are needed to have the system work autonomously with the closed-loop feedback set up since it is still too harsh.
Future Work:
The mechanical design of the system was mostly complete but has room for improvement. The lower links that are attached to the back plate have been supported by having two identical links on both sides of the back plate to create better support on the link holding the cup. Doing this "sandwich" of links created the stability necessary to move the cups in a smooth path. However, this same method was not implemented on the top link connected to the back plate. It would be ideal to add more support to the links since they currently have some play. However, it is important to keep in mind that adding more weight to the links will create more issues with the DC motor as more torque would be required. Additionally, it would be more difficult to control the links' motion to pour and catch the liquids without having too much inertia. For future iterations, the closed-loop feedback would need more time to test the code. What we found is that the motion of the cups was what we wanted, but the speed and timing for pouring and catching were not ideal. Even when the speed of the system was slow enough to potentially minimize spillage, the force of the links caused the pouring link to lose balance and fall onto the back plate, causing errors in the feedback. In the future, the links would be better controlled to facilitate the pouring and catching phase.