“Dance like a fly, bite like a mosquito!” - Doc Louis, Mike Tyson’s Punch-Out!
Every year, I create a LEGO robot using Mindstorms EV3 (now discontinued). This year, I decided to take on the perennial challenge of building a Robot in 3 Days.
I started on Saturday, the evening after kickoff. Straight from the game animation, I knew that this would be a game that required both inspiration from Ultimate Ascent (2013) and STEAMworks (2017) to create a very powerful and replicable machine. With LEGOs, it is more complex than you would think to design mechanisms that work like that of a FRC robot.
This ground intake for Notes was partially inspired by that of the 2019 hatch panel ground intakes and 2017 Einstein ground intakes. Using a singular motor, I was able to create a Touch it Own it intake that was easily handoff-able and foldable inside the robot. It took about an hour to get the geometry to work correctly with the frame perimeter and the edge of the bumper, but persistence prevailed. At the end of Day 1, I had a functional ground intake.
Day 2 posed another challenge: The shooter. I spent nearly the entire day prototyping a mechanism that would be able to toss the ring at least over the bumper of the robot with some force to prove the concept.
Initially, I had tried to incorporate a ratchet and rubber band system into the adjustable height shooter, but that proved ineffective when the lifter was not sturdy enough to support the pulling force of the rubber bands and ended up breaking.
The original wheeled prototype was able to use the adjustability successfully, and was able to get the Note over the bumper of the robot. However, it had some flaws. One of these flaws was that the Note would not get enough speed coming out of the second holding wheel (similar to that of the Kitbot) to get some distance. To improve this, I moved the wheel a couple studs back and made the wheels spin faster thanks to improved gearing. This worked to perfection, and tests proved fruitful.
Also on Day 2, I added some passive climbers so that it could have a chance to climb the chain. They will most likely be replaced with a motorized climber once more concepts and robot reveals start to come out, since I still have one motor port left for something.
The final day was rather short, given that I had school on Monday. The last day was used to glim and glam up the robot, add some graphics, and “polish” the bumpers (just dust them off). The last feature added was the rod on the adjustable shooter, to push open the Trap and fire a ring inside. It can also be used to line up an Amp shot. I ran a complete test of the functions, and after removing the underglow lights (they were causing the drivetrain to be wonky on one side), the robot was finished. At least for now.
To go over the functions list, Little Mac 2 can:
- Pick up Notes from the ground
- “Handoff” the Notes to the shooter
- Shooter can adjust, and shoot into the Speaker and Amplifier
- Shoot into the Amplifier using the intake
- Do a passive climb on the Stage chain
This thread will be updated as revisions are made throughout the build season.