RI3D Reveal Questions

My team is building a robot that is inspired by many, many different reveal videos. One particular video I saw that I had some questions about is the RI3D video. Please watch through the whole video before replying.

Question 1: Where is the slip gear? Without a slip gear, they wouldn’t be able to fling a catapult that fast with rubber bands, but I don’t see a slip gear in the pictures of their gears.
Question 2: Question 2: How are they able to compact themselves? At around 4:07 they compact themselves into the space required, and then miraculously unfold (kind of explode) into their full robot. Our team is currently struggling with ways to fit the size limits, so this question is especially important.

I ask these questions because I am confused with this. I’m not a Vex expert and I’m excited to learn, so please don’t judge me because I’m confused.

You can see pictures of where the slip gears are at 2:55, & what they look like at 3:03 in the video.

The climbing arm and catapult arm start folded down as seen at 4:07. When the catapult arm initially fires, it locks into the climbing arm with polycarbonate hooks. You can see the lift lock at 3:59 in the video.

Was about to respond to that but seems like @Nathan Rossi got it covered. You might want to check out this thread: https://vexforum.com/t/robot-in-3-days-teaser/35573/1

I have a question about programming the limit switches. Arm stops as soon as the limit is tripped but won’t continue forward to engage the slip gear. any suggestions? What am I doing wrong or not doing?

I spent about 60 or so hours reproducing a robot similar to the Ri3d and it was very hard. I do this every year and it seems to work but you need to have diligence if you want to get an efficient design.
Good luck

Why not just use a potentiometer then to grab the values of the potentiometer, and use the formula "
motor[Catapult1]=(-SensorValue[Potentiometer]/1)" This is a very simplistic P control loop :slight_smile: To make it slower or faster, mess with the “/1”.
If you want to display the angle of the potentiometer, use the formula “SensorValue[Potentiometer]/15.5” and it’s a very rough estimate of the degree of measurement.
What it does is the motors will gradually decrease when the potentiometer gets closer to 0, and if the motors are away from 0, then the motors will fight to make it to that angle.

Let’s see Robot in 3 days, 60 hours leaves 12 hours for sleep. That’s about right.

But 6 hours of sleep each day decreases productivity.

Not necessarily. I am averaging 3-5 hours and I am fine.

I average 6 a night IRL, and I function (mostly) fine, only a few days do I get sleepy. For such a short time as 3 days, an hour and a half of sleep should be fine, depending on the time of day.

It is recommended to have 9:30 hours of sleep, and how in this green earth do you possibly handle such days without energy? At the least, have coffee or gatorade to keep your energy up…
Besides that, I think that it is interesting to have a normal sleep routine, then save your energy for a 3 day build which you can have practically non-stop free-time. It seems actually very fun!

The lift is held via lexan hooks that would hook onto the catapult when it goes down. Then with the intake, they basically have a lock kind of like in this video:

EDIT: It’s the same concept as the video, except as a different form.