So after searching around the forum for awhile I have not seen much talk about VEXU stuff, especially the new rule on materials allowed on the robot. I wanted to start a talk on possible questions people have, and some questions I have that some people might be able to help with. Also with so much more freedom of building, what kind of things do you guys expect to see change?
Personally I hope to see people try out more precise gear ratios, machining their own gears and axle sizes. I believe every robot would be able to make a reasonable transmission for this game (And every robot should make one). I suspect lifts are going to be more efficient, more compact, and run on less motors (can’t wait to lose to a 1 motor lift). I’m excited for Vexpro bearings more than anything, just the ability to use ball bearings is a game changer in efficiency and friction. I’m also excited to see VEXU when there are no two robots that look alike because they all have custom machined parts, it’s one thing to copy a vex bot by counting holes in a picture, but you can’t do measurements on a piece of sheet metal unless you are actually there at the robot. What are you guys excited for?
Honestly, i might not be in VEXU, but i expect to see FTC style robots.
Also I looked at the rules and saw nothing against welding so far. Any thoughts on if you guys are gonna try welding your bots this year?
You had the exact same thoughts as I did, ball bearings and transmissions! LOL I was not even considering VexU this year, since they made it 1v1. But bringing back lg/sm vs lg/sm plus almost free reign on materials, total game changer. I hope this gets more seniors like me re-interested in VexU, and maybe even some of the FRC people (I always forget its HS too, not college level)
I wouldn’t try welding just yet without an official clarification. Because Appendix E (VEX U) is silent on welding, <R16f> in the original manual still applies. However, my interpretation of is that for this “unique [steel or aluminum] component”, it may be welded together itself in the fabrication process, but not welded to any VEX Robotics Design system component.
I love the open-ended aspect of all the mechanical aspects of VEX U this year. I think this will be one exciting year for it. Might be considering a comeback…
Is the 2 tank limit still there for VEX U?
good point there, but what if then entire thing was a custom part 
If you’re making a custom part yourself, you can weld that together to make it. You just can’t weld it to a design system component like I said.
I think the better question is, are they even going to let us use pneumatics this year. There is a line in the new rules saying no actuators, which we have come to understand that usually means pneumatics. Others have brought up this question already right here Use of Pneumatics(VexU) - VRC > Turning Point (18/19) - VEX Forum but no clear answer has been given yet.
Explain more about why you think there will be more transmissions in VexU. I would have thought there would be more in VRC with the motor limit. With unlimited motors, it seems that the need for a transmission would be eliminated. Perhaps I’m not fully understanding all the applications of a transmission.
@Gear Geeks
I was thinking more along the the lines of multi-speed transmission, not so much a multi-output transmission. 2 speed drives could be insanely useful, with climbing and pushing.
Well even with the unlimited motor rule, there is still the limited battery, and it doesn’t look like we get a power expander yet. This leaves us with a theoretical motor limit, which all depends on how much power you draw from your motors. It is true we could have a 20 motor base coming off of 2 ports with 20 Y-splits, but the power draw from the single battery would probably kill it in one match with all 20 motors running at full load. Transmissions are great if you want to get more efficiency out of a drive system or lift system. To put it simply, a transmission takes the output speed and makes it lower speed with higher torque, or higher speed with lower torque. I assume you might be thinking of transmissions as a way to split a motor to two different systems, like in NBN where some people would take half the motors off their base and run a linear puncher with it. That is technically a transmission, just not the most common one.
So this year I expect to see everyone with speed to torque transmissions, Speed when you need to get somewhere quick, Torque for when you gotta use defense of some type. I’m going to try and make mine automatic so that when the motors feel a spike in amps, indicating that i’m pushing something, it’ll go into torque mode and save some of the motors strength. Hopefully that answered that question.
Ah. Makes total sense! Can’t wait to see it!
Your post made me reconsider doing VEXU. After all, now there is some serious mechanical engineering going on. But then I remembered that eliminations will still be best of one. It’s hard to justify spending hours, days, weeks, months of my life on something when I can lose in a heartbeat, to something potentially outside of my control. Source: happened to me already.
Personally I find appendix E (VexU) extremely ambiguous this year. (Not revealing all the shenanigans I’ve thought of just yet), but as a preview, VUR3 does mean we can make springs as spring steel is steel.
Yes, I had a similar thought… Or they will hopefully allow springs outright, along with expanding the hardware allowed up to 5/16-3/8 (M8-10)
Rulebook already says we can use “small” field kit screws and nuts.
Albeit there’s nothing stopping us from making custom screws, threaded rods, etc.
Yes, but that’s not exactly ideal for making 50+ of something…
That being said the only screws I have ever bent was trying to get it out, not in use. So larger hardware might not be needed except in certain locations.
I try to justify this by saying “Hey, if I want to one day be working on the robots and rovers we send to distant planets that we only get one chance at ever making it work, maybe this will be a good example of how real life really is.”