As you know I’ve been a champion for getting 3D parts accepted into the rules. I recently got a hard pushback that “3D printed parts are dangerous, they can come apart and pieces fly everywhere”. And while my use case for 3D printing is brackets, support pieces, new claw configurations, better sliders for the metal slides, a better range in sprockets, I hadn’t considered roboteers printing exploding parts.
I know that many of you look at injected molding plastic parts as just a beginning point for modifications. I want to hear your stories about how you / your team / some other team / some other team that your cousin knows a roboteer on that talked about a different team in another state / etc. built and destroyed a part. Anything from the classic “we were trying to keep weight down so we drilled 1/2” holes in the 64 tooth gear that was attached to 3 traction wheels and when we spun it up to 9200 RPM it came apart" to your latest misadventure. Don’t limit to shooting games, happy to hear about crumple time with your double - double reverse 4 bar that tossed parts.
Post them here, or for those of you under non-disclosure / afraid of your insurance coverage being pulled, send them direct to me. I’ll change names, place and times and repost them.
This story isn’t about my team in the past, but there was one time at a competition where another team from our school put their robot on top of a bleacher. The bleacher was folded up to save space. The team captain sat on top of the folded bleachers, and he was basically sitting on top of a wall. Lo and behold the robot fell off and one of the shafts on the drivetrain got obliterated. The thing was bent like 70 degrees and they were panicking on how they were gonna replace it.
While VEXU’s size is considerably smaller than VRC, they have been allowed to use 3D Printed parts for sometime. It would be interesting to hear from them what their experience with these have been.
Teams and mentors said it was a very good to great experience. RECF that attended VEXU Worlds were blown away with what teams had built. I asked about exploding parts and there was no verification.
Another side to look at it is that screws help by standard nuts have a habit of vibrating off the nut, leading both to come loose during competition. If such screws were then to hit a robot’s flywheel, they can become quite the projectile, which is why RECF requires anyone at the competition field to wear eye protection. While I’m biased, I would think that the current risk posed by these projectiles is no different than a future state with 3D printed parts, from a liability perspective.
Are you trying to make the connection that modified plastic parts should be illegal because you received some feedback that “3D printed parts are dangerous, they can come apart and pieces fly everywhere”? If so, that’s quite a leap…
I’m also not sure where “3D printed parts are dangerous, they can come apart and pieces fly everywhere” came from.
I was involved in the discussions about 3D printing being legal for this season. The perils of 3D printed parts falling apart was never mentioned. What was discussed, and mentioned by Grant during his VRC game overview session on Wednesday at the REC Summit, was:
VRC is a (mostly) kit a kit based competition where teams are working from approximately the same set of parts. This helps keep the playing field mostly level. There are some external factors that might favor some teams over others, but at the end of the day the playing field is fairly level.
If you really want to scratch that itch to 3D print parts, there are programs like HS VAIC as well as some of the other programs the REC offers to teams.
While 3D printers might be more common in classrooms today than they were 3/5/10 years ago, there is still a wide gap between the quality of 3D printers classroom to classroom and school district to school district. So not only is there a gap between teams with and without 3D printers, but there’s a gap between teams with a cheap $99 printer and a $2000+ printer. This doesn’t help maintain a level the playing field.
Almost every team has (or has access to) a hacksaw, tin snips, a power drill, etc. These can be used to modify sheets of plastic and metal. So why aren’t teams allowed to use unlimited sheets of plastic and/or metal in VRC? Because then teams with access to mills/lasers/routers would have a huge advantage over teams without these resources. This doesn’t help maintain a level playing field.
By that same logic, I’m curious what the argument is against implementing a rule set that allowed for limited amounts of 3d printed parts to be used in VRC, like what was in VexU?
It would be (fairly) comparable to the lexan mill/laser/router part of the equation, in my eyes at least.
I believe the difference between a team with tin snips for (limited) lexan and a team with a router is just as comparable in the competitive advantage gained by using the more expensive tool as would be for a team using a cheap 3D printer and a team with a pricier one (with a 3D printed part limit or something of the like)
Sure, not everyone has an Ultimaker S5 (just like how not everyone has a router to work lexan) but I think it’s silly to cut off such a powerful opportunity for learning 3d manufacturing, when cheaper- just as competitively viable alternatives (like an ender 3) exist. Point being, people still manage to make things work (and learn from them), even with cheaper tools.
But, I guess this brings us back to your initial point about VRC being kit based, which I think is a valid, albeit limited approach : /
@Jon_Jack Thanks for the replay of what Grant said.
In the following meeting there was a comment made on how dangerous 3D parts could be over the current suite of Vex parts. In over a decade of VRC(FVC) I’ve seen my share of parts flying. Reasons range from not fastening things down to creative applications of cutting to create things that fly apart.
So I asked for the community to post their best structural damage stories. I don’t like to be a data point of one.
Since you posted what the GDC is thinking, its apparent that we won’t get 3D printing into VRC at any near timepoint. I did suggest that RECF along with all the new programs they are creating add a VRC-Unlimted for HS students. They would play the same game, rules, etc. The only change would be unlimited 3D printing and since teams really like using it unlimited polycarb. This would give “elite and well funded teams” an outlet for their creativity without disenfranchising teams with less resources. Not sure if that will go anywhere.
But I’ve given up tilting at the 3D windmill, for roboteers that want more of an engineering challenge with less parts restrictions I’ll send them over to the FTC competition.
To level the playing field when it comes to printer quality, you could make a list of legal printers, plus anything below a certain market value, and then add a rule similar to <VUR5> except with the focus being on the type of printer used. Additionally, VEX could legalize only certain types of filaments to prevent teams from getting an upper hand by buying extra high quality filament.
Personally I think that adding in very restricted 3D printing would be very useful educationally, and would promote the use of CAD software from a younger age without having too significant of an effect on the competition.
All of which are great ideas that someone needs to push forward. Maybe the Student Advisory Board can take it up.
I’ve always taken this as a program that should be ever evolving and ever growing. Going from 0.5 PIC to Cortex to V5 has been great along with constant improvements with motors. But I feel from a mechanical side the EDR line is pretty stagnate. I’d like to see some different shaped brackets, some more variety in the size of sprockets, parts that would enable transmission design.
I would like to see the custom parts of the on-line design award winners to be allowed in the following seasons. Maybe they are useful, maybe not, but they are there to inspire roboteers.
Much as the HEXBUG vast array of parts is starting to appear in robot designs now.
Vrc does have a differential gear set, but I’m not sure as to how good it is. It’s also quite large. As for planetary gears, do the gears in the motor cartridges count? (Lol)
I tried using the differentials back in In The Zone for a passive transmission (different from the one with the two big gears and motors on moving arms) and had a few of them snap. They aren’t very good in terms of friction either, and I have a feeling there was some skipping, although I’m not sure that was with the stock differentials or the custom ones I made later as I was working on them. I was feeding 4 393 motors with the turbo gear ratio through each one, so there was a decent amount of power going through them for these issues to occur.
I met with a student from our local VEXU team yesterday. I asked them about this point…
They had a 3d printed drive train for a season a couple of years ago with no issues. No exploding parts. He was quick to note that you have to use the right type of plastic, just like you can’t use plexiglass, but if a 3D printed drivetrain is fine then I have no idea what their case is.
He also said that it’s really nice going to a VEXU competition because there is much less design convergence. You get to see a large number of different robots.
Imagine 3D printing to not be allowed due to plastic flying around when the GDC makes seasons where robots can shoot plastic, drop plastic on people, and even have metal that can fly off robots. Yet if the biggest argument against 3D printing is plastic flying around that is honestly far fetched as VEX robotics heavily utilizes relatively dangerous systems and procedures but in controlled environments.
But when it comes to the aspect of “Even playing field,” that is a pretty good argument nontheless. But if that is the case then let’s stop releasing a multitude of sensors that are fragile yet expensive that give competitive advantages.
If VEX Robotics is so concerned about affordability, then why would they add touch screens on a V5 brain alongside unnecessarily adding encoders to every single motor boosting costs? It just sounds more like a selling point and commercial game as compared to making a system that is affordable to the average individual.
If we are getting to a point where VEX sells a whole universe of parts, completely and hypocritically shattering the ideates of “affordability,” then why can’t we have a whole universe of parts outside of VEX as well?
