NbN OpenLift concept - legally lift with 16 motors

I can see how the elevation aspect of this game is going to raise some major trust issues between alliance partners. Having your $2K robot dropped from 12 inches high will very likely put you out of the game for at least a week or two, never mind the cost of repairs. Fail-safe mechanisms in these lifts will be a must. Elevation systems that provide free-fall situations might be looked upon with less enthusiasm than, say, ramps or other devices that fail in less dangerous ways.

I just want to emphasize how important this point is that FullMetalMentor is making. We will most likely never let any robot pick us up that we have not thoroughly inspected and practiced with in the pits. It’s to much money at stake. On the flip side, we hope to make a robot that is able to elevate other robots efficiently and we would not expect our alliance partners to let us pick them up without thorough inspection/testing of our own bot.

Seeking out and communicating with your alliance members during qualifications will be very important this year. (it always is, but even more this year)

There are some scenarios you can eliminate right off the bat.
-5" omni wheels do not exist in VEX so unless someone makes custom ones, this won’t happen. And why would someone do that? Any team with the technical ability to make custom wheels is also smart enough not to- that is why we’ve never seen 5" X-drive in past VRC seasons.
-I can think of 4 examples of static robots ever in VRC and one of them exploded itself trying to turn into a giant 6 foot arm. Another was a wallbot (now practically illegal). The other two were in skyrise, in which you could build your whole tower from your starting tile. None of that is feasible this year, so I don’t see any teams trying that.
-I’ve never seen a kiwi drive in person, and I haven’t seen one in a competition video for years.

It’s my opinion that you can save yourself time and effort by figuring out which scenarios you DON’T need to deal with before you start.

I like the idea of an Open Concept lift and I will have my teams discuss scenarios but I will also encourage them to seek ways to depend less on the other team. If you could lift yourself then you could be successful with anyone.

I asked whether or not a robot could lift itself on the field perimeter and, if I interpreted Karthik’s answer properly, I was told such a move would be illegal.


So I guess your self-lifting system would probably need to find something to suspend it besides the field perimeter or any other field elements. Of course you can lift yourself, but no part of your robot can be below the low or high plane when the buzzer sounds.

EDIT: um, uh… well it looks like my interpretation of my answered question was wrong as there was recently another question posted whose answer seems to indicate a robot can elevate itself.


I sure hope Vex makes this issue crystal clear in their next rule update.](https://vexforum.com/t/answered-updated-previous-elevating-q-a-clarifications/29473/1)

Yes, this is very good point. It always felt that this year’s game is not as easy as it seems. Now we are discovering more and more specifics. It is good that we learn at least some of them now and not half-way in to the season.

But if you think about safety - then every lift system pose a falling risk, if not correctly implemented. You have potential energy in your elevated robot, regardless of the lifting method.

Ramps need to have good guides, cranes and all other lift types need to manage COG and rely on wormgear or some sort of brake to prevent unwinding. But I don’t think the risk is greater than that of falling robots in Skyrise. 12" to the field floor is not as bad as falling off the edge of elevated field into alliance station (note to myself: if building ramp then add good stops at the end).

My bad, I still have largest omni wheels and 2.5" c-channel sitting next to the keyboard. Somehow I thought of them as 5". But even at 4" they barely fit on the inner edge of 2.5" ramp, assuming there will be some guides on the outside edge.

Yes, I have never seen static robots in person, but several Skyrise videos of such design were very exciting to watch. Even if they are not performing well against the “proven concept” robots - it is what we all are looking for when encouraging thinking out-of-the box (not static robots per se, but variety of designs).

I’ve seen 3 wheeled kiwi drives and number of 5-wheeled robots for Skyrise. I hope to see some of those experimental designs this season as well. I wish, somebody builds symmetrical 6 (or even 8) wheeled omni drive and we could see how it behaves and if it would make any sense. However, if everyone decides that ramps are the way to go, then people wouldn’t even think about those designs.

I, actually, think that some of the best alliances could combine two lifting robots and a 6 or 8 motors robot (with removable ramp) that could outrun and outpush everybody on the field. Such robot outfitted with an OpenLift attachment could make it through qualifiers with a ramp and then just dominate the open field during eliminations.

I totally agree with that. That’s what we are trying to do here.

It looks like my interpretation of my answered question was wrong as there was recently another question posted whose answer seems to indicate a robot can elevate itself.


Or maybe I’m incorrect in that interpretation, too. :confused:

Or maybe I’m incorrect in that interpretation, too. :confused:

Yes, it is still confusing with “provided that no other rules are violated…” but word “resting” is something new and it reads like self-elevating is allowed. However, with double lifting out of the picture, there is not much incentive for it. Here is my reasoning for it.

First of all, I think, everybody will agree with the following goals:

  1. We want to see great game and new ideas on all levels. We want to encourage everybody to come up with the designs and strategies that expand some boundaries. Both out-of-the-box designs and “proven concept” robots that show an extraordinary level of excellence in the design, build, and strategy.

  2. The second goal is for each individual team to seek the best design and strategy for winning.

  3. We want to see great level of cooperation. Ideally, we want to find a way to give competitive advantage to the teams that take cooperation to the next level. That makes 1+1 = 3 to work for such alliances.

If you ask me what I remember from Skyrise season - it will be AURA vs QCC2 matches. It will be high and middle school teams that made it to the finals. But I remember most Team 62 for their 7-high Skyrise in autonomous and 185A for this match. It isn’t easy to express emotion through the robot, but 185 Alpha did it very well! Then I would remember SYNC, Arty, and InspectorGadget’s dual bots and a number of other unusual contraptions. Some of them didn’t win top awards but they all, definitely, pushed some boundaries just like the winners.

For #1 we want to see all sorts of the unusual designs this year. There are several good ways to do high elevation. If it will not require every team build to some common drive-train specification, but is easy to participate, with minimum design accommodations, then we will see some out-of-the-box designs. We, probably, will see them anyway, but if they have a path to 50 point elevation it will be better.

For #2 if you just plan for qualifiers and assume that your partner is a random robot then it is true, the best strategy would be, not only to build good launcher, but to ensure that you are getting 50 elevation points no matter what.

One way of doing that would be to “bring your own hanging bar”, set it on the field perimeter, and self-elevate. Even if your partner is nothing but a replica of [Sharkando 3, you could give them a decorative balloon, that would have a point above 12", self-elevate, extend your robot’s arm and touch it. But planning and committing scarce power, space, and time resources for such unlikely case is not optimal.

For both #2 and #3 the optimal strategy is planning what is best for the alliance.

In qualifiers - it is planning for any random partner that is willing to cooperate. For eliminations it is planning for the non-random partners of your choosing that compliment your robot.

Some things that are good for only #2 may not be optimal for the alliance. You may want to avoid resource duplication that are used only once and figure out if there is a way to utilize all resources at the alliance’s disposal at all times.

Alliances with partner specialization was there all previous years and everybody knows that.

But is there a way to take cooperation to the next level? Is there a way to let alliances parallelize as many tasks as possible, including lifting, and reward them with some extra time?

OpenLift could be one way of doing that. That’s what I wanted to emphasize by the thread title. Most likely, you will never need 16 motors for the lifting, but the idea was to allow alliance to utilize resources that are impossible to have for two individual robots taken separately.

OpenLift may be not the best way to materialize such idea, but it gives some options. If somebody could think of a better way - that would be great! Please, share it!](“https://vexforum.com/t/7580a-2015-robot-reveal/28927/1”)

I would say there is plenty of incentive for creating a self-elevating robot. By building their own lift system, a team can optimize the speed at which they lift. They will know their particular weight and center of gravity issues, so their lift can be customized for their own robot. All that a self-elevating robot asks of its alliance partner is that it drive over and touch them before the buzzer sounds. A “touching mechanism” might be as simple as a zip tie added the morning of the tournament. Even a clawbot or pushbot should be capable of doing that.

Yes, it is true, by self-elevating you avoid uncertainty about power and COG constraints associated with a random partner. Similarly, robots with ramps don’t need to worry about the required lifting power, since partner will use its drive-train for elevation.

In the absence of the common lift standard, self-elevating would be the best strategy to ensure individual success, but not necessarily alliance success.

Let say, the robots, that made it to eliminations, are roughly divided into being 2/3 self-elevating, and 1/3 ramped robots (with 6 or 8 motor drive-trains). All those robots were successful, because they have dealt with an unknown of the random partner (weight) and used their power resources more efficiently. There could be few other robot types that made it past qualifications, but I cannot guess what they would be, so I will not talk about them.

There will be some level of cooperation beyond specializing in certain tasks - you either need to drive up the partner’s ramp, or you need to touch self-elevated partner. But, it feels, there will be missed opportunity to take the cooperation to the next level.

Obviously, being self-reliant is better and gives more chances of success. But this will likely lead to some underutilized resources.

For example, two self-elevating robots are playing in the alliance. One will be self-elevating, while other robot’s self-elevating hardware will be sitting idle. It is still an open question, if it would make sense for the alliance to try to utilize all its resources.

Will it save valuable time for other tasks or will it just make alliance strategy more complex and easier to make mistakes?

At this point, I agree that simpler is better, but it is very tempting to search for a reliable alliance strategy that could make 1+1=3 work.

Only one robot on an alliance is allowed to be elevated at the end, so the achievement of high elevation can get your alliance a max of 50 points at the end. From the standpoint of winning or losing, whether you utilize all your resources or not matters very little since you maxed out your 50 point possibility.

If your intention is to dazzle the audience with some kind of outrageously clever lift system that only two highly-integrated robots could perform… well, that’s a different story.

Yes, I know double elevation is not allowed any more. What I meant to say, was that there are two robots capable of self-elevating. Only one will self-elevate at the end of the match. On the other hand, it gives them a backup plan.

Anyway, if it is legal to “rest” on the adjacent perimeter walls, and nobody is interested in any standard lifting interface, then self-elevation capable robot is the best option for any team that could build it.

The only reason against it would be if you don’t want to risk tumbling from the perimeter top into alliance station, if partner, instead of gently touching, runs into you at full speed. But then you just stop elevating at 4" and keep you COG behind the wall.

If everybody decides to do self-elevation then geometry of the field will pretty much dictate your robot optimal design.

You have to be square in the corner and you have to push on the perimeter walls near two diagonal corners of you robot. You could choose between some sort of linear lifts or an expanding hanging bar, and winch yourself up. Hanging bar option seems better because it has single power delivery point and you don’t have to deal with the torque in the lifts.

If you want to keep shooting preloads, while preparing to elevate, or even while elevated, then you launcher needs to be aligned with the other diagonal, from the perimeter corner toward the net.

It is possible to have dedicated lifting motors, but if you are capable of building a transmission, then it would make sense to source your lifting power from the drive-train.

Finally, if you build transmission, which all advanced teams will at least consider, then you will likely stick with X-Drive because your robot will be naturally symmetric across diagonal aligned with the launcher.

I am a little disappointed because, I don’t see much of the design freedom. There must be optimal design and most of the teams will figure it out by the end of the season. Unless I am missing something crucial here, then 80% of the robots at the worlds will look alike.

If there was an option of double elevation or single robot was prohibited from touching two adjacent walls at once, then we could see more different designs.

I can’t wait to see the designs that high elevate while simultaneously shooting (and scoring!). Who can afford to waste 12.308 seconds doing nothing but elevating? :o

Oliver W, have you got that working yet?

If you put dual opposing one-way cogs on your shooter motor drive train,
you can run them forward to shoot,
and run them backward to provide lifting power, with zero motors dedicated to lift.

If you have energy stored somewhere (like elastics), it takes little power to trigger it for a one-shot application like a lift in the last 10 seconds,
so there is no need for 16 motors tightly coordinated between 2 robots.
Use a force balance cam or some other governor so your lifter doesn’t become a robot shooter…

Give your alliance partner a cheap, simple-to-install, lifting interface.

Build into your robot a variety of mounting points to install your alliance partner’s lifting interface, if you like theirs more than yours.

I like the idea of a 4bar hook that starts vertical and ends up horizontal 13 inches high. (Think of holding the Stanley cup over your head)

But a vertical lift hook (or fork lift) with pop out wheelie bars is less intrusive into the rest of your robot.

Edit: And we can stop trying to avoid the intent of Elevation rules, now that the intent has actually been mentioned in Q&A: