I already have a 1m intake built w/ tray as well as half of a 2m DR6B. The tilter is the one thing I have left to build. I understand it is not easy, but how difficult it would be has been really over exaggerated. The only big problem I have found so far is spacing, not so much motor distribution.
This is my exact motor distribution.
Also note that the tray doesn’t need to be at full capacity when going up. Rather, it will act like a regular tray bot (deposit 8-9 cubes at once) for some of the match (probably at the start). Then it will be able to use the towers effectively and possibly add to a pre-existing smaller stacks for the later portion of the match.
This would be useful when you’re paired with a weaker team or just a generally more versatile robot for any kind of alliance. If you were to stack on a pre existing stack, you’d only do 4 cubes max at a time, as you said, the mass of the cubes adds up quickly.
That’s exactly what I have done, except it is a regular dr4b. I’ve thoroughly contemplated ways to maximize spacing and I have a very good solution I think. The tilter is probably going to be the hardest part to get down, I have an idea that uses rubber bands and pulleys in order to aid in the deposit. Also, the tilter will be mounted on the bottom portion of the top linkage if you can visualize that. Also note, the tray will have a passively expanding mechanism that is tensioned down to have perfectly straight stacks.
The reason I’m throwing my ideas out there is because I want more teams to build upon them as well.
I’ve thought about a simpler version of a tilter that could be more space efficienct and the only thing I can ever come up with is a small 4 bar, my only concerns with this is weight over size as it being on the top of a DR6B, and while I won’t reveal it I know the hight to be very tall and the more I think about the more unstable this becomes
Watch some skyrise videos, particularly 185a. Remember they were on v4. I want to note how high their lift goes, I’m not exactly sure what the mass of skyrise cubes were but they were larger than the TT ones.
Bracing is something that will aid in stability but you really need a low center of mass. This means strategically putting the motors and battery as low as possible on the chassis and away from the deposit (in a dr4b the weight shifts forwards so mount these towards the back of the robot). @Freshscott
Oh I get that, I trust his abilities to make a solid lift without a doubt and I understand that these capabilities are fully possible my concern is tho that with a tray, tilter, and 6 or so cubes up at said unmentionable height I’m worried about tipping and all…
This is a valid concern, I agree with you. There are measure you can take to not tip of course, but let’s say even after you build a prototype it becomes a problem that hinders your mobility significantly, I think you’d be better off with a different design or strategy (less cubes in the air preferably).
I have designs that would accomplish that such as what RI3d is doing with their odd DR4B but on the current lift he’s making but I want him to try out his ideas first. It is only the summer so theirs plenty of time to grow
Ok as builder of the robot, I can assure you my main concern is tipping, especially with how tall the final iteration will end up being . But I have thought of many ways to counter this: A. we have a base built like a tank with most of the weight to the back(already built) B. passively deploying anti tips primarily to keep the robot from falling backwards or forwards C. A speed limit built into the code that multiplies the input to the motors inversely proportional to how high the lift is at the time. I hope these countermeasures are effective at keeping the robot from falling over during matches and or practice.
oh and maybe you could count are fairly rear mounted support tower for the lift, so once it is lifted all the way up the weight is much closer to the center.
Only thing I can really say to that is we will have to wait to find out!
Those are great solutions. I really like the one with code, I could see this being very useful for skills when you are zooming across the field with no defense as the driver might get carried away. Also, I don’t know how selective refs will be if you tip when someone is defending you if your lift is all the way up as they can use the “design flaw” card. Regardless, I really like your solutions to this issue.
We will primarily be stacking in the protected zone, and don’t see much reason to have our lift raised (unless we decide to do towers later in a match, in which case our lift will not even me close to max height) so the only times our lift will be fully raised is in the protected area, and possibly the unprotected area if this design proves to be efficient enough to completely stack the protected zone before the match ends
I agree with this strategy, I think I mentioned this here
The unprotected zone would be better used in autonomous in my opinion. Stacking on a pre-existing stack under defense it too risky.
Im surprised I never thought of that, I will definitely have to implement that later
Oh and I think I have a secret goal to make a large lift every season (I was a cap bot in TP lol)
A well planned autonomous route and good programming will enable you to max out your cube capacity and deposit within the 15 seconds. I think a lift bot should be able to have at least 7 cube max capacity to be competitive although we haven’t seen any because most robots were made in 3 days. I am referring to the design described above (a lift-tray bot combo).
Honestly, I initially dismissed the tray-on-DR4B idea as impractical due to the heaviness of the cubes. But looking back on it, it seems like a pretty good idea. Nothing is faster than a tray at intaking, so some sort of tray-based design is ideal. One thing this design gives up really is (potentially) the intake speed (less motors at same torque means less speed), although something like this will still be much better than a vertical reverse stacker.
One key thing to note is no matter how slow the lift is, the robot will be no worse than an equivalent basic traybot. The lift is only used when adding to existing stacks, which will likely make up a pretty small proportion of match time.
A key concern that I and others have brought up is cube capacity. One thing to note here is that a robot need not be able to lift all the cubes that can fit in it’s tray. For example, I could make a robot with a 12 cube capacity tray that can only lift 6 cubes. This obviously isn’t ideal, but it would still be just as good as a basic tray at making new stacks, and just as good (or potentially better due to the increased intake speed) as a basic DR4B reverse stacker at adding to existing stacks.
This is the design I was referring to in a conversation you and I had earlier in another thread, I am glad to see you have changed your mind on its potential. There are obviously things we have to figure out as a community to see what works best, but this is a step in the right direction.
Yeah, I started building my rollers yesterday, and I have to agree. One motor rollers likely won’t be viable
I think it’s a bit too soon to come to conclusions on the viability of 1 motor intakes. We’ve seen that they’re possible, and they’ll just keep getting better with tuning. Having an extra motor to use for another mechanism will be a huge benefit that might outweigh the decreased power and increased complexity of a 1 motor intake.