Big Sky Robotics is back again for another Robot in 3 Days for 2025 Reefscape.
We will be streaming 8am - midnight MST on our YouTube channel with a special guest host this year!
We plan to update this thread throughout our process with strategy decisions, images/videos of prototypes, CAD screenshots, and final mechanism/robot status. Please reply to this thread with any questions that you have for us throughout our build.
To prepare our new members for the build this year, we did a 9-hour mock kickoff in November using Power Up as the basis. Students brainstormed, prototyped, designed, and assembled two separate mechanisms for picking up game pieces. Both mechanisms were in great shape at the end of the build, and if this mock kickoff is anything to go by, we have a great year ahead of us!
Yes, we plan to release full CAD. Later tonight once the storm of sending parts off to be fabricated is mostly over, we will send some screenshots of some mechanism CAD and prototypes.
CAD will be posted here, youtube day 2 recap coming soon. Will post some screenshots of robot CAD soon, an overview can be seen in our day 2 recap and we can answer any questions regarding the design here.
As Ri3D bots go, this one figures to be very complex: 4 total DoF with 3 stacked. With the robot almost entirely finished, it’s now up to our software and controls team to make it shine. We’ll also be posting the full (more polished) CAD tomorrow in this thread, so be on the lookout for that! Feel free to ask any questions you might have and we’ll do our best to respond in a timely manner.
This robot’s complexity very quickly grew on us as we dissected the game and determined what we would need to accomplish our objectives. Ultimately, we ended up with this:
Thrifty elevator with some slight modifications to fit our design, driven with 2 NEO motors;
22-inch arm attached to carriage driven with 2 NEO motors;
Herringbone gear driven wrist with an end effector for coral scoring on all four levels attached;
Drop-down intake capable of both coral and algae pickup, and algae scoring in the processor
The robot is designed to hand coral off from the intake to the end effector. Due to time constraints during full robot integration, our very promising prototypes did not function as well as we’d hoped, with the coral failing to consistently “stick” in the intake when it pivots up. However, this should provide a very solid proof of concept for teams should they want to try and tweak the geometry to improve it.
We intended to include a hook for the shallow cage that attached to the elevator and had it designed and ready to install, but a focus on software and solidifying coral scoring on the reef took precedence, and we were forced to omit it. However, it would be very easy to add such a simple hook to the elevator should the geometry be correct.
Due to some issues with SOLIDWORKS exporting files, we kept all parts and subassemblies together in a ZIP file. Please let us know if there are any issues with viewing the files, or any questions about our design.
A robot reveal will be releasing later tonight. We’ll post the link to it here when it’s ready, so be on the lookout.
We wish all teams luck in 2025 Reefscape, and can’t wait to see what others come up with!
Back in 2020 my Ri3D group was able to go to a competition around week 4 of build hosted by one of the other groups. I don’t believe that it has been redone since the pandemic but it would be awesome to see one organized again, it was a really great way to get gameplay insight before competition season started.
Here is the plate we used for prototyping. It does not include the full axle and wheel configuration but has the right geometry. Feel free to play around with it in your design.
I’m assuming that your bot is able to score the other levels, but it wasn’t shown in the reveal. How did coral L1-3 go in your testing, and how well does the algae score work?
Due to very limited time to program, we were unable to test L1-L3 scoring with the bot doing all the work. We did test manually moving the arm/wrist and were able to score on the other three levels just fine. As for algae scoring, same thing: the running assumption is that we angle the intake up slightly and eject, which we did test with the original prototype, just not on the bot. Hope this helps!
Hi! I was wondering if you guys could talk about or post some video showing the robot doing ground intake with the coral in different types of orientations. It would be very helpful as our team is struggling with deciding on ground intake/human player station. Thanks!
Do y’all have any advice for teams who want to try a ground intake similar to the one on your final robot? The “V” shaped intake seems to be a very desirable concept for a lot of people on our team and I’d like to hear about any issues with it and how you might go about given more time. Thanks!
