Re: Drive Systems... ...The FIRST Arms Race?
 

I agree. I think that there has been a trend toward a more-pushing style of play, and it has contributed to more powerful drives. But the reasons for it - and the solutions - could be addressed in a different way.

I think the number one factor determining how we play the game is the game design. Not the kit, and not the robot rules. If the game design enables teams to do nothing but push others around and still be "successful," then teams will do it. This has been the case in the last few years (and probably this year too).

If the game design has a valuable feature that only requires robots to deliver in the last 15 seconds of the match, my guess is that teams who optimize for those 15 seconds are going to have some time on their hands to go stir up some trouble for the remaining 2 minutes.... IMHO, this feature of the game has nothing to do with how many motors we get.

If the game design has some really important yet difficult feature, you know, something crazy like shootin' balls through a hole at 30 feet, and many teams say that task is too much to handle, I think its highly likely that they are instead going to play some D on the teams that do shoot well.

Don't get me wrong, the robot rules have an impact. For example, the near-mandate for bumpers has, in my opinion, encouraged teams to ram into each other because now its "safe." Maybe the rules and refs should just say "don't ram into each other."

The kit has an impact too. When teams get a kit part that works great, they'll use it.

Maybe its better to use the game design, and not the kit+robotrules, to steer the horde of us robot-builders. I would rather be amazed by some creative games and designs than be forced to see lookalike robots from every part of the country (oops world). I think its more interesting and inspiring. So, let us use our motors freely, with lots of current, efficient transfer of power, and some serious traction. Then give us a game that makes our preconceived notions obselete :).

I remember going to Houston in 1998 and seeing a bot that could move sideways. Talk about inspiring.....

Re: Drive Systems... ...The FIRST Arms Race?
 

With no disrespect meant to anyone, I think we have enough limits put on us. They tell us exactly how to do everything. If they now tell us exactly how to build our drive train with the exact gear ratios and the exact wheels and the exact motors, and the exact metal to use, and the exact shaft to use, then we will have no creativity left.

I also disagree on the part that FIRST is encouraging pushing and shoving matches. They have told us exactly when we can push in and pin in the rules book. I think they want to see teams become creative with mechanisms to cap the rack.

I do agree that they gave us too many motors, but I still think its good. Anyone who decides to put them all on their robot is going to have a tough time on the field. There isn't a strong enough battery and the most robots wont even have enough weight for it. The game demands for these options, though.

Re: Drive Systems... ...The FIRST Arms Race?
 

Dont forget motors weight alot. So sure put 8 motors on your drive.

Re: Drive Systems... ...The FIRST Arms Race?
 

We have...:D

Re: Drive Systems... ...The FIRST Arms Race?
 

Yes, there has been an increase in the number of motors used on drive trains. But, the weight constraint keeps the robots’ pushing power in check. The grippiness of the tread available to us is currently limited, and with a maximum weight of about 148 lbs, a robot’s pushing force is bounded. With a shifting gear box, and proper ratios, the 4 small CIMs allow robots to have enough torque to spin their wheels against a wall, so the motors’ power is not the limiting factor.
Sure we might be able to slip the wheels faster, but a robot must be controllable, so the speed is limited too. And with shifting gearboxes becoming more accessible, there isn’t much reason to slip your wheels at 15 ft/sec. So, although there has been a Drive System Arms Race, other physical factors keep it in check.

Also, another potential solution is to limit the number of powerful motors (motors above 100W). The 2.5” CIMs, 3” CIMs, and FP motors make up ~85% of the total motor power. If, for instance, we only had the 4 small CIMs and then many less powerful motors, teams that want to get ahead in the FIRST Arms Race would have to slap on six extra motors instead of just two FP or two large CIMs.
I don’t know about all designs, but based on my experience I don’t think many other components require the power that a solid drive system does (except, perhaps, last year’s shooters), and we have pneumatics we can use. I really like the banebot motors, because they should be powerful enough for most arm/fork lifts, yet it would take three banebot motors to equal one CIM on a drive system, which just isn’t that practical for most teams.

Re: Drive Systems... ...The FIRST Arms Race?
 

With FIRST crack down on weight this year I believe that the drive trains will be turning to less and less motors but with more and more design put inot making them more efficient.
This year we have a ver nice Drive train, it's accully a BEAST and was build with 2 speeds in, but we removed the faster one for weight reasons, and we bend a battery bolder when doing 360's with it, just from the centripital force >.>

Re: Drive Systems... ...The FIRST Arms Race?
 

Bigger, badder drivetrains will only get you so far in the world of FIRST. The best and most successful robots are those who innovate and design conservatively. The best teams are those who understand their robot inside out, and understand design limitations and design advantages. In other words, the teams that have a knowledge of what they are doing are in my mind the best teams.

This year our drivetrain is using two large CIM motors. And they do just fine, working great with our custom transmission. I will definately say that our drivetrain is modest compared to other, but mechanically it works, and that is key. I have seen many other teams with outrageous transmissions that are being pushed to (and sometimes beyond) their limits. Mentioned before, defense will only get you so far. Last year at SVR a student said something that I will always remember, that " defense doesn't show up on rankings". Teams that score point will always move the crowd.

I believe that FIRST includes too many motors. Really, 4 CIMs is really unecessary, as they simply seem to encourage teams to use them in tandem and the two large CIM minibike motors. I think FIRST should eliminate some of these drivetrain motors. My suggestion to encourage creative design is to change the rules to allow teams to dissasemble the window motors to use their electric motors, while at the same time allowing only two small CIMs and two large minibike CIMs for the robot.

I also want FIRST to bring back great games like 2004 and before. From waht I have heard, I missed out on the greatest game ever played, and from 2005 till today the field has been pretty much the same. I want FIRST to go back to having more obsacles and game pieces so that teams must dedicate themselves to specific tasks. This year I have seen FIRST make a move toward this, as teams are making hard choices in going with ramps, arms, or a combination of both. So I like where FIRST seems to be headed.

Re: Drive Systems... ...The FIRST Arms Race?
 

After thinking a while on this topic, I've decided to come back and offer another view. It might have been said already, and if so I apologize for restatement.

FIRST is giving us tools to deal with engineering issues in the real world. In the real world, there are no motor number constraints on an issue. If a problem needs 10, or even 15 motors to create a solution, the engineeris will add just that many motors. So I don't see the arms race as that much of an issue. Sure, more tourque helps. But you will find the teams that do the best have the simplest drive systems, and instead have poured their focus into the manipulators.

All in all, what my slightly mangled logic (I need sleep, and breaking a caffeine addiction isn't helping) is trying to say is that we're preparing for the real world, and so limiting something as trivial as motor quantities makes little to no sense. Instead, teams should be given too many options, and should have to sort through the possibilities, in order to learn about simplicity and design elegance, rather than just shoving as many motors onto the system.

[/soapbox]

Re: Drive Systems... ...The FIRST Arms Race?
 

You just stamped in the point I spent way too many characters trying to make! Go C7H10O4N4!!!

Re: Drive Systems... ...The FIRST Arms Race?
 

I understand exactly what you are saying with this and how much work is done off season (if any at all) on the base, but the thing everyone is missing out on is the fact that the manipulator and autonomous modes and other things change EVERY year and that certain subgroups on your team have a "static" position, meaning they have to think and come up with something completely new, while others just innovate older designs et cetera. That is why the BASE or DRIVE SYSTEM of teams is becoming more and more interesting every year from what I have seen on the forums (including archives) because the base usually stays constant or at least the framework or principles of it does.

I think the energy rule is limiting just as how you choose your motors because if you are limiting energy than you are saying you have to cut power from "A" and add it to "B" and that is similar to saying you can only use "N" amount of motors out of the number given for a certain operation (drive train, manipulation, et cetera).

Pavan.

Re: Drive Systems... ...The FIRST Arms Race?
 

Yeah, I completely agree - it's difficult to do some of the work with Autonomous robots and sensor manipulation because it does change so rapidly from season to season, and it also depends upon the game as to whether it makes sense to invest the time in the technology. Take this year's game for instance, there is very little need for an accelerometer and/or a gyroscope - while some teams may take advantage of them to help them with some of their autonomous actions, the green light and the camera are all you really need to create an effective autonomous (some would argue that gear tooth sensors are all you need, but I digress). This year's game also didn't really need those sensors for in-game use, so for the most part they were played with and then set aside.

A lot of the responsibility for getting teams involved with the more advanced control system design is in the Game Design Committee. If they came up with a game that relied heavily on a particular type of sensor (or sensor fusion) then teams would embrace it. For instance the camera was a huge part of last year's game, the accelerometers were huge the year they had teeter-totters, and this year you've got ... nothing, really. I mean, you have 2 light sources which allows you to play with tracking/identifying multiple lights, but it isn't even mildly critical to the success of a robot. As far as I'm concerned the only "cool thing" they brought out this year was the lifting of the robots, and that doesn't even impact my controls team... though I must admit we did use the extra time this year to have a little bit more fun with our control system!

-Danny

Re: Drive Systems... ...The FIRST Arms Race?
 

Danny, I couldn't disagree with you more. Sensors will be vital during all phases of the game this year. Especially when trying to acquire and place tubes on the far side of the rack, sensor aided systems are going to be a huge advantage. 116 is using more sensors on our robot, particularly our maniuplator, than we ever have (at least to my knowledge). A total of 10 sensors may see use during our matches this year, and most will still be used during teleoperated mode. At one point we may even have automatic alignment software fully functional, so that we can align directly with a spider foot on the far side of the rack.
Sensor integration and navigation software are aspects that can be worked with over the summer to a certain degree, but not nearly to the extent as drivetrains. Because we don't know if we're going to have the camera, or an IR beacon, or any other kind of "target" next year, certain sensor specifics are really a risk to spend a lot of time developing during the off-season. Same with certain navigation frameworks (this year having a field element that changes placement between matches made navigation software harder).

Re: Drive Systems... ...The FIRST Arms Race?
 

Like the original poster said, a reason for this escalation is because of FIRST game designs.

I think this is in fact the main reason.

Take this year's game, for example. Rack'n'Rolls main scoring device is ONE device, in the middle of the field. Most of the gameplay SHOULD happen nearby it, therefor not that much movement and a robot that can keep where he wants to be is paramount. Sadly, i think FIRST made a slight error in point values with the bonus, which makes creating a robot that in no way plays a scoring game until the end an actually viable(and very sadly, winning) solution. So, what would the builders of this robot do with the rest of the time? DEFEND!!! against those teams that make a robot which actually plays during the match. and since those teams made a robot that is not 100% geared and weighted for defense, they most likely wont be able to out-class the defense machine.

the point I'm trying to reach is....If robots with pushing power were not useful, ppl wouldn't make them, would they?

Just my 2 cents.

Re: Drive Systems... ...The FIRST Arms Race?
 

I think Manual Labor is on to something here. Drive systems have had a chance to be perfected over the past few years due to a relatively similar playing surface each year.

I agree with everyone here who says no more restrictions

What I do agree with is making these perfected drive systems at least partially obsolete.

6wd has seen an incredible jump in popularity over the past few years. Why not make a game in which 6wd and other common systems work, but which aren't the best style for the game.

We've seen many many different types of manipulators over the years because of the different game pieces. Why not translate that to the field and drivetrains? Force teams to innovate to get a competitive edge

Re: Drive Systems... ...The FIRST Arms Race?
 

Some of us rely on "off the shelf" parts. We are a team that has a hack saw, drill press, ruler and a lot of ideas. We do not have the equipment needed to make individual parts. Our high school doesn't even have a metal shop. It would be impossible for us to make a transmission, for example, so we either use the one in the kit or purchase one from a manufacturer. Last year we used 4 motors because we designed primarily for defence. (It was our rookie year and felt that trying to design for using the camera may have been above our abilities.) This year we elected, once again, to go with 4 motors, not for defence but rather to have the ability to climb ramps if it is necessary. Sure, we would love to manufacture our own equipment, but it ain't gonna happen.