Introduction
Team 5996, R. U. R. is a small team based in Prague, Czech Republic. Every year we have between 10 and 15 students and 3 mentors. Last year, we ran a prototype OpenAlliance thread on our website, which we shared mainly with team 9585, which is the only other team in the Czech Republic. This year, we feel confident we can run a full build thread on Chief Delphi.
Last year, our team won the Regional Engineering Inspiration Award at 10,000 Lakes Regional. We strive to adhere to best practices of mechanical engineering and hope to inspire future generations of engineers by attending Maker Fairs all over the country. Below is a photo of our robot and a warning about what could happen when you make your hook tolerances too tight:
As for manufacturing capabilities, we own a CNC mill/router that we use on all plates and tubes on our robots. One of our mentors has a rather small lathe, where we can manufacture custom bolts, pins, and hubs. Lastly, we love 3D printing and in the past couple of years, we’ve managed to run various 3D printed mechanical components without a single failure, including rollers on our 2024 shooter.
I’ll be using primarily metric units as it’s easier for me to convey and I’ll try to remember to go back and convert at least the most important ones.
I’ll let this intro end with a fun fact: Did you know that the word “Robot” came from the Czech language? It first appeared in the play “R. U. R.” by Karel Čapek.
Strategy
This year’s game is very interesting, we even brainstormed the usage of cylindrical scoring elements in November, as we haven’t seen those probably since 2015 pool noodles. The one-defender system calls back to 2019 when one defender was able to shut down one of the isles.
First, let’s talk about Algae. From our perspective, Algae isn’t a very viable scoring option for us as scoring into the Processor nets only 2 points and shooting it into the net for 4 points would require packaging a large shooter inside Robot Perimeter, which doesn’t fit our other design requirements for the robot. Furthermore, interacting with Algae doesn’t directly affect RP progress. Therefore we’re completely skipping Algae shooting and Processor scoring will be a nice-to-have.
Corals are a fun new game piece to interact with. Corals feel that they will be easier to handle than cones because they have holes on both sides. Based on points gained, they’re netting at least 2 points on L1 and they directly affect the Coral RP. To achieve the Coral RP, we have to reach all 4 levels of the Reef. The Coral Stations are conveniently close to Reefs and they seem to drop Corals a bit faster than what we saw last year with Notes. Despite that, being able to collect rogue Corals from the ground seems like a should have.
Next up is the Coopertition bonus. We don’t want to rely on having the Coral RP threshold lowered. Furthermore given there are more RPs to earn, Coopertition points will be less likely to affect the overall rankings.
The endgame seems fairly difficult. Being able to climb on the deep Cage to obtain the endgame RP more easily is very tempting and we consider it a should-have. If all fails, climbing the shallow Cage seems very approachable even with last year’s climber.
Mechanisms
Let’s talk about some mechanism ideas that we’re working on right now. Considering the size of our team, there’s no way that we can build too many prototypes simultaneously, therefore we’ve put together a vision that we want to explore in-depth to iterate on in later weeks.
The drivetrain decision was very straightforward for us, especially considering that we finally replaced our old MK2s with shiny new MK4is. The question remains if we want to go for a L3 or L3+ gearing. Considering the short travel distances, acceleration is going to be key as we aren’t very likely to hit top speed this year. The chassis width doesn’t seem to be a huge issue this year, therefore a square 650x650 mm (25.6")
seems a good fit for us unless electronics + pneumatics packaging forces us to go wider.
For our ground intake mechanism, we’re testing a full-robot wide roller intake, which will treat the Corals just as regular balls. From our early testing, it turns out that the more misaligned the axis of the Coral and the axis of the intake rollers are, the easier it is to get hold of the Coral. We tested using 3D printed Mecanum wheels with close to no result as there is no grip. Furthermore, we tested misaligning the intake from the bumpers, so that the gap gets smaller towards the front of the robot. This helps to funnel the Corals towards the front of the robot. We’ll need to make a more precise version of this to see the results more clearly. If we want to be able to streamline the process of intaking Corals even more, we can fit two intakes on the robot.
Here is a link to a video that we took when testing the intake.
For the Coral manipulator, we want to build something that doesn’t require realigning Corals once we intake them into the robot. From this, we landed on the same idea as one of the Ri3D teams. We can create simple V-shaped basins which can tilt using pneumatics and the Corals will be deployed by gravity.
To be able to get to L4 on the Reef while maintaining a fairly low profile (700mm (27,5") of height maximum), we’ll need a 2-stage elevator with a movable carriage, which will carry the Coral manipulator. With the reef pipes being only about 330mm apart, we want to explore the possibility of having 2 basins for the Corals, which would make lining up much easier. In this case, each intake would feed one basin. The downside to this is that if we fill the right basin and want to score on the left side, we would need to realign the robot.
To climb on the deep Cage, we want to use a lifting mechanism that would push on the bottom plate of the Cage, thus lifting the robot. Given that the Cage is only about 90mm off the ground, we don’t want to lift the robot much higher than that, because then the robot would become an inverted pendulum. We would like to use pneumatics to achieve this climb. We found a large pneumatic cylinder that has double the lifting force we need and it still fits into the cage. Therefore we need to create a guiding mechanism for the cage, which will guarantee that the cylinder goes in every time. Furthermore, to achieve a perfect line-up with the Cage, we want to put a conical nut on the end of the cylinder that will fit inside the hole of the bottom plate. There are two things that we need to take into consideration. The center of mass must be placed perfectly in the center of the robot as any tilt would likely discount the climb and we need to calculate the stress applied to the parts holding our climber. Unfortunately, our Cage is made out of PVC at the moment, so we’ll be able to test it once the real one arrives.
Right now, we can’t share any precise dimensions as all is a rough sketch that overlaps on every corner. I believe that we had a 5 mm (0,2") compression on the Coral using 2,25" compliant wheels with various durometers. I will confirm the intake dimensions once I get my hands on the measurements we did on Saturday night.
There will also be a write-up on pneumatics soon as we really need to get it sorted out. We used pneumatics back in 2022 and had leaks all over the shop. I can confirm that that was caused by mixing 6mm fittings and 1/4 in tubes together, which seemed to fit well together, but the sealing wasn’t great.
Feel free to ask any questions, I’ll try to share as much as I’m able to. Or if you find a fatal flaw in any of this, please let me know! 
