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

[Jaine Perotti]

Originally Posted by Joe Johnson

I have not really been on a team for 3 seasons now -- perhaps 4 depending on how you count things. From the outside looking in, I seems to me that FIRST has become an Arms Race of sorts, every year there are more and more teams with more and more motors devoted to their drive system with grippier and grippier treads.

There are a number of reasons for this trend.

• FIRST game designs have encouraged pushing matches.
• Too many motors have been introduced to the kit [1]
• The FIRST KOP transmissions have encouraged 2 Motors per side (4 motor drives)
• It has become easier and easier to implement multimotor drive systems with very grippy tires [2]

Dr. Joe -

I definitely haven't been involved in FIRST for as long as you have, but within my scope of experience (5 years in FIRST), I disagree when you say that defense has been on the rise. Even back in 2002 (the year before I joined my team), a strong drivetrain and lots of pushing power was very important. In 2003, defense was king. Ever since 2003, I feel that defense has actually been steadily de-emphasized. In 2004, defense and offense were about equal in importance (the ideal balance in my opinion). In 2005 defense was almost completely eliminated from any place of importance. Last year, defense was slightly more emphasized, but you still couldn't win the game on defense alone. It's tough to make a call about defense this year yet, but certain rules (i.e. - you aren't allowed to de-score opposing ringers) lead me to believe that FIRST (the GDC at least) is trying to balance the forces of defense and offense (if not outright giving offensive teams the advantage).

Also, the addition of more motors to the kit does not necessarily mean that FIRST is trying to encourage a drivetrain arms race. More motors could mean more easily facilitated (and more complex) offensive arm designs as well.

I'm not going to disagree with you on your last two points, but I don't think that those two facts are necessarily a bad thing. How many teams would want to use the KOP transmissions if they felt that they would be inadequate in terms of pushing power? Correct me if I am wrong (you are probably in a better position than I to judge this), but I don't think multimotor drivetrains are any more prevalent than they were in 2003, my rookie year. I think that in encouraging teams to use 2 motor/side transmissions, FIRST is just trying to level the playing field by providing a competitive solution that is accessible to all teams.

Originally Posted by Joe Johnson

BUT... ...from FIRST's point of view, I think this is bad situation.

• It is harder on the field elements
• It is harder on the other robots
• It makes teams do a lot of extra work just to keep up, for limited competitive value and almost no inspirational value.
• It is no fun to watch (imho)

I am unsure about your first point. I think the wear and tear on the field elements is highly dependent on the nature of the particular game. I would say that most damage to field elements are more commonly the result of intense offensive play, as opposed to defensive play. For example - the tetras in 2005 broke frequently as a result of long falls from offensive arms. Balls in 2004 were popped by grippers and claws and rollers. The 2006 balls were chewed up by shooting machines. However, one could attribute carpet damage and other field damage to defensive play. It seems to go both ways and I am not sure of the overall effects of offense vs. defense on the playing field.

As for your second point, yes, you are probably right. More defense will result in more damage to other robots. However, one could say that this encourages teams to be come up with more robust designs (a good thing, IMO. It's important to engineer robust solutions in the real world - not just elegant or showy ones).

I definitely disagree with your last two points. I really don't think it is too much extra work to design for 2 motors/side as opposed to 1. If I'm going to sit down and design a transmission, it would probably take me the same amount of time regardless of how many motors I wanted to use. Plus, the 2 motor solution is easily facilitated by the KOP (or at least it was in 2005 and 2006).

My main disagreement, however, is with the statement "limited competitive and inspirational value." Innovative drivetrains have certainly shown their value in competition. On my old team, 716 (and many other teams, I'm sure), the drivetrain was always placed at the very top of our priority list. We knew that we would not be able to do anything effectively if our drive system could not meet our needs. For example, we decided that we wanted 2 speeds so that we could play defense effectively, but still be fast enough to move around the field and complete our offensive tasks. This meant that we needed to design and manufacture our own custom transmissions.

How is it less inspirational to design a custom transmission than to design an end effector? How is it less inspirational to design and manufacture a mecanum wheel than to design a turret? I think any design project like this is a beneficial experience to the students on the team. It doesn't matter whether it's a part of the drivetrain or a part of the arm; as long as the students see the end result of their work, both are inspirational. Just look through the pictures on CD media tagged with "drivetrain", "wheel", and "transmission", and try to tell me that there is no innovation occurring within those disciplines!

Also, I think that defense is a very important and necessary part of the game (strategically and in terms of its "interestingness"). However, I do believe in a balance between the two elements. In the perfect game, an excellent offensive team should be able to beat an average defensive team, and an excellent defensive team should be able to beat an average offensive team. 2004 was the perfect example of a "balanced" game - good defense AND good offense could win a match. In 2003, the scales were tipped too much in favor of the defensive teams; conversely, in 2005 the scales were tipped too much in favor of the offensive teams.

On a side note, how can anyone say that defensive play is boring to watch? I will never forget the 2004 finals and semi-finals on Archimedes when my team, 716, was faced off against some of the strongest defensive (as well as offensive) bots in the world! That defense was some of the most intense (and visually and emotionally awesome!) that I have ever seen (494, you are amazing). It was heart pounding and exhilarating - I wouldn't ever want to trade that for a technically interesting, but rather boring exhibition of robots that are just scoring (and no one is trying to prevent them from doing so). The presence of defense makes it even more amazing to see high-scoring robots perform - knowing that they are experiencing difficulty, yet are still able to overcome!

Definitely do not impose limits on the amount of power in the drive system. As it is right now, the amount of power a team can have is already somewhat limited by their coefficient of friction against the ground, so potential power is not infinite (after a certain point, the wheels will just begin to spin against the carpet in a pushing match). Yes, the extra power will help in acceleration, but there comes a time when too many motors becomes more costly in terms of its draw on the battery (and less motors available for other manipulators) than it is worth. I don't fear that defense will intensify in the likes of an "arms race" for these reasons (as well as the fact that it's obviously not being encouraged by the GDC). Also, it would be costly in terms of battery power to use ALL of the motors in the KOP. Thus, teams will have to learn about restraint in their designs and make responsible choices about motor selection.

Thanks Dr. Joe for bringing up this discussion. It's very interesting, and I hope I don't sound as if I am being argumentative. Just trying to share my two cents! You definitely have a much greater perspective on the evolution of FIRST than I have.

-- Jaine

[Billfred]

Originally Posted by Tom Bottiglieri

I'm not so concerned about power in the drive. If the team builds it well and can control it on the field, what does it matter?

I'm more worried about people buying these new, off the shelf mecanum wheels and not knowing how to program for them correctly. What a waste.

This is a real issue. This year, our drive system was biased towards going off-the-shelf when possible. The result was a 6WD with Gen2 AndyMarks. Works beautifully.

Overall, I agree with most of the points raised in the thread. However, I think the solution isn't so much in meters and lines on the inspection checklist. The solution seems two-pronged to me.

1) Cut down on some of the drive-grade motors, and perhaps work in some more arm-friendly motors. Drop a couple of the Big Powerful Motors (herein defined as the CIMs, big and small, and the F-P), either individually or in pairs, and throw in a couple more window motors. I mean, sure you can do window motor drive, but most teams will just work with less power there.

2) Create game objectives that value finesse and agility over pure brute force. Rack 'N Roll, Triple Play, and (to an extent) FIRST Frenzy can arguably meet this criteria. Aim High, Stack Attack, and Zone Zeal couldn't to the same degree. Make it so we've got to move fast to score well, and we'll do it.

[Greg Marra]

Originally Posted by Billfred

2) Create game objectives that value finesse and agility over pure brute force. Rack 'N Roll, Triple Play, and (to an extent) FIRST Frenzy can arguably meet this criteria. Aim High, Stack Attack, and Zone Zeal couldn't to the same degree. Make it so we've got to move fast to score well, and we'll do it.

I disagree with you about Rank 'N Roll encouraging a maneuverable drive train. If you don't have the stickiness and the power to stay put when someone is trying to push you this year, you will have no chance of being able to score a tube. precision manipulation with an arm requires a stable base, and if a team is trying to nudge you, they probably will be able to.

I want to see games with more variety and strategic possibilities. I think adding the three different weight classes of robots this year was a really interesting idea. What if they took the idea even further and limited classes even more? We might see even more innovation and teams working to fill specialized niches, as in the 2004 game. The past three years there has been a single viable objective for teams. This year starts to change that a bit with the idea of a "carrier robot", but there really isn't enough differentiation.

Force teams to do something other than push hard and do one thing well.

[Corey Balint]

Originally Posted by Greg Marra

I disagree with you about Rank 'N Roll encouraging a maneuverable drive train. If you don't have the stickiness and the power to stay put when someone is trying to push you this year, you will have no chance of being able to score a tube. precision manipulation with an arm requires a stable base, and if a team is trying to nudge you, they probably will be able to.

I want to see games with more variety and strategic possibilities. I think adding the three different weight classes of robots this year was a really interesting idea. What if they took the idea even further and limited classes even more? We might see even more innovation and teams working to fill specialized niches, as in the 2004 game. The past three years there has been a single viable objective for teams. This year starts to change that a bit with the idea of a "carrier robot", but there really isn't enough differentiation.

Force teams to do something other than push hard and do one thing well.

Greg, I gotta disagree with you on the weight class idea. They are going in the right direction, but I think they need a different type of variance. I really dont see alot of designs changing drastically do to this rule.
Raising the Bar, in my opinion, is the best game FIRST has had. It had alot of variance. You could be a ball manipulator or you could hang, or you could do both. In recent years, you basically had to make an arm or make a shooter. There really weren't multiple options. FIRST needs to concentrate more on making those options available. They don't need to have different shaped game pieces (that might make it too difficult), but they need many more options. This year, you dont have much to choose from.

[Joe Johnson]

Originally Posted by BurningQuestion

Dr. Joe -

I definitely haven't been involved in FIRST for as long as you have, but within my scope of experience (5 years in FIRST), I disagree when you say that defense has been on the rise.

snip

-- Jaine

I really appreciate everyone's very thoughtful comments. It was much much more response than I ever expected on the day before shipping.

I just want to make 2 points:

#1 I never even used the word "defense" in my posting. I am not against defense and that was not the point of my post.

#2 I misstated my point when I said "It makes teams do a lot of extra work just to keep up, for limited competitive value and almost no inspirational value." I SHOULD have put in there "almost no additional inspirational value"

Trust me, I am a HUGE believer in the inspirational value of drive trains. Building & competing with remote control machines that can DRIVE is a fundamental ingredient that makes FIRST work. My point is just that I don't believe that having the average number of drive train motors climb from 2 to 4 to 6 to 16 is really a good investment in terms of the added inspiration for the extra effort expended.

Joe J.

I personally believe that the issue lies in the lack of creativity required to move about the field. This comes from the flat fields that we have seen in recent years. Think of AIM high; an entirely flat and open fields. Yet if you look at previous year's fields, there have been midfield ramps, gates, giant teeter-totters, steps, and other elements that encouraged creative drive systems.

We can look at the common drive systems that we have been seeing lately, it is clear that the field has required nothing more than a high torque box on wheels. If FIRST were to bring back complex fields, we would see more innovation, and teams steering away from massive pushing machines, as they would be forced to use the weight more conservatively to achieve motion.

[side note: My personal idea for a challenging field would be a steel piping grid, suspended about 12 feet above the field. Bonus points would be given to teams that could play the game without touching the ground throughout the match. Even more points would be given out to teams that could intentionally change from driving to hanging based on phases of the game]

[Richard Wallace]

Originally Posted by 114ManualLabor

[side note: My personal idea for a challenging field would be a steel piping grid, suspended about 12 feet above the field. Bonus points would be given to teams that could play the game without touching the ground throughout the match. Even more points would be given out to teams that could intentionally change from driving to hanging based on phases of the game]

Monkey-bar robots would be cool.

[Protronie]

I like the idea of NASCAR robot racing...

I agree... it seems the team with the most motors and biggest corporations
seem to have any edge. Maybe the time had come to set limits (hello restricter plates).

I've a friend in Levle Cross that's really into NASCAR. He's told me and showed me some of the tricks the race team would try to get an edge or bend a rule to its limit. Back in his day #43 was a real threat on the track.
Some of their trick really took some smart engineering.
I could see teams trying some tricky engineering here too but maybe we're getting away from what FIRST is... the robots and the games are third...

Learning to work together as a team, making friends, and learning how to deal with deadlines , problems, and challenges should be second.

Learning how to think, how to deal with people, how to lead, and learning if you set your mind to it and apply yourself, anything is possible should be first and foremost. IMHO

[Jeremiah Johnson]

If memory serves me right... QC Elite has 6 motors in the drivetrain, and 4 on the arm. Ten motors all together. Super agile robot and a little bit of pushing power. Four inch IFI traction wheels, also.

This is the first year we've implemented more than 4 motors in the drivetrain.

Does anyone remember the first crab steer systems? Did they have a million motors?

[Stephen Kowski]

Originally Posted by Joe Johnson

My point is just that I don't believe that having the average number of drive train motors climb from 2 to 4 to 6 to 16 is really a good investment in terms of the added inspiration for the extra effort expended.

Don't you think though that this situation that you are commenting on is a trade off that is directly linked to the game given by FIRST. The games recently haven't been incredibly complex in the ways of scoring so teams have the extra weight to spend on large powerful drive trains. I agree that we have probably have more motors than needed, but I also see more and more drive trains becoming lighter and lighter as people experiment with different materials so they have the weight for those motors.

How about weight classes for motors, which make a harder tradeoff rather than just height....maybe 5lbs less for each motor powering the drive train above two?

Also, even though carpet is a great, readily transportable item that is available all over, maybe it is a time for a change, that has been a constant for a lot of years....what about something like the safety squares that they sell (pictured beneath 27) http://www.chiefdelphi.com/media/photos/20302

[Jessica Boucher]

If we're still trying to gain traction in a market that is going to take a very long while to warm back up to competitive robotics, we need to keep growing. Defense and pushing is a very viable tool for growth. And, it's not like we're stuck with the same format every year - the game does change.

Go ahead, make the game more conducive to using those motors in other places. But don't restrict their use. It's the best tool we have.

[Joe Johnson]

Originally Posted by Budda648

...
Does anyone remember the first crab steer systems? Did they have a million motors?

Team 148 had a drive train for Toroid Terror in 1997 that they could turn sideways and spin the goal tree after docking with it. It wasn't exactly swerve, but it was a close cousin.

Team 47 had Swerve on its 1998 robot for Ladder Logic*.

Going from memory that year there were 2 drill motors, 2 Seat Motors, 2 window motors and 2 Delphi Power Sliding Door motor.

Joe J.
*We won 3 regionals that year and were very competitive at the Championships. That was the last year that they had 1-on-1-on-1 game format with seeding on Friday and a Double Elimination tourney with everyone in it on Saturday. For those who where there they probably remember it as the year with the Looser's Bracket from Hell. There were about 10 really great teams that ended up in the Looser's Bracket and only one was getting out to the semi-final round. I think it ended up being the TechnoKats and they went on to win it all that year.

As another aside, Raul-the-Magnificent and the rest of the Wildstang crew probably recall it has the year of the Egg Shaped Ball that cost them a National Title. They had their patented suction ball holder protecting that 1 ball they had on the Ladder with a bunch of doublers in the middle goal. The only the Egg Shaped Ball wasn't touching both rails!!! Into the Looser's Bracket from Hell they went...

[Jack Jones]

Arms Race? What arms race?

[Not2B]

I like this idea. Maybe set it up to encourage an efficient drive. I'm sure there's lots of good ways to do it...

But I like this idea alot. I think alot of teams put time, weight, and MONEY into drives just to survive the matches. I think it just drives the cost up. And alot of teams just go out and buy solutions to the 4 motor drive.

Where do I sign the petition?

[Andy Baker]

Too many motors in the kit? bah. We're using 5 this year. Time will tell if we are good in 07 or not. Comparing what I see now with how we have stacked up over the last 10 years, I like our chances.

Each year, you can find teams with simple designs and low amounts of motors winning matches consistently.

More motors = designs that try to do it all = difficult to control robots = lost matches = frustration.

Sure, FIRST gave teams 16 motors in the kit. I agree it is too much, but for a different reason. If a team is silly enough to use them all, then they have other problems that will bog them down for the season (too heavy, lack of control, etc.)

Best of luck to all,
Andy B.