2 Speed Transmissions in the Future

[RyanN]

Originally Posted by Cory

No, they wouldn't.

$500 is a very significant amount of money for a lot of FIRST teams. More than many have available to build their entire robot with.

Any increase in price would not be well received by the FIRST community, even if it is "only" $500.

In addition, there's no reason that a low cost, reliable alternative to the banebots transmissions can't be included in the kit.

I would think that FIRST could get with some company to manufacture parts for a 2 speed transmission so that the total cost of each transmission is less than $50 each. Our 2005 and 2006 2 speed transmissions were custom made by us and they were very reliable, and I would say that the materials in it did not go over $30 per transmission.

[Cory]

Originally Posted by RyanN

I would think that FIRST could get with some company to manufacture parts for a 2 speed transmission so that the total cost of each transmission is less than $50 each. Our 2005 and 2006 2 speed transmissions were custom made by us and they were very reliable, and I would say that the materials in it did not go over $30 per transmission.

There's no possible way, be it by buying gearstock, or individual gears that the cost of materials will be less than $30 per transmission. I wouldn't see any possible way for the material to be less than even $75-100 per side.

The Banebots transmissions hover around $50, and they have very poor build quality. It simply wouldn't be possible to pay for materials, and labor to machine all the parts required to make a two speed transmission.

[Michael Corsetto]

I think that if FIRST keeps pumping out games with the same relatively flat field with maximum of 30? inclines to climb, you will see more and more 2 speeds. There just isn't a challenge for teams to design anything besides a basic 4"-8" diameter, 4 or 6 wheel drive train. Its related to the arms race thread, but on a broader scale. Most teams wont try to make a V6 or anything like that, but with all the previous designs out there, a 2 speed isn't that much of a stretch for any semi-experienced team.

And there are teams out there that have almost reached perfection as far as 2 speeds go. 254/968 has the most elegant and thought out drive train I have ever seen. And it helps that they have had at least since 2004 to work out their design. I'm not quite sure if you can get any better than a 1.4 pound 2 speed gearbox (great job Travis btw) and I would doubt their entire drive train came out to be over 35 pounds. Thats 85 pounds to do whatever else you want to do with the robot! Being the one who is always working on arms/manipulators, it would be nice to be able to make something without having to worry if the drive train is gonna take up all of the robots weight.

In short, yes, as long as games continue to have fairly repetitive field layouts, 2 speed will become better and popular-er (is that a word? )

Mike C.

[Doug G]

Shifting Transmissions are somewhat overhyped. We were very competitive this year and didn't use them. 2006's game seem to be wide open and we used AM shifters and got good use from them. You just got to look at the game to see if it's worth your investment of time and money. If they release another game like 2004 First frenzy, I suspect most experienced teams would invest time and resources to other robot attributes.

This seems to be a thread twice a year on average.

[=Martin=Taylor=]

The assumption here also seems to be that tank-drive wheeled robots are the future of FIRST.

Omni and meccanum are barely controllable in low gear. Swerve drives are complex enough without the addition of multiple speeds. Track-drives have a tendency to throw belts at high speeds...

Not that these drive systems are incompatible with 2-speeds, its just that most teams are unlikely to build them.

There are other-ways to improve drivetrian usefulness then to add another gear...

[Bharat Nain]

The use of 2-speed transmissions has gone up a lot since AM came out. I think the reason they are used widely is because they are so readily available. Some teams decide to custom-build theirs and do a decent or excellent(254/968) job on it. I think the use of 2-speed gearboxes is going to go up in the years to come. FIRST has encouraged defense in the past 2 years and 2-speed transmissions are one way to face the challenge. I don't think they are going to change the rules because defense on the field is good to see within limits. Swerve drives, crab drives(45, 116, 1114 and so on..) etc are very cool but they are also complex to build and very time-consuming. That is why teams stick to tank-drive and do very well in competition. It also matters what a teams goals are when building a robot. Some build purely to win competitions while others build for the "cool" factor. Some are good at both and some have neither. 2-Speed transmissions will go a long way because they are ease to buy and install. They are also very effective.

[Gabe]

The use of any drivetrain will depend entirely on the game. As long as FIRST has a field with no serious obstacles, then 2-speeds will gain popularity. Although I was not there, the 2004 challenge didn't really seem to favor multi-speed transmissions because on top of the platforms there was no need for the high speed, with very little room to maneuver. If there is any serious obstacle the driver must slow down (except for the few who try to fly). The more obstacles, the fewer opportunities there are for the driver to use the fast speed. I know FIRST is itching for an obtacle field, so plan accordingly.

[Alan Anderson]

Originally Posted by Gabe

...the 2004 challenge didn't really seem to favor multi-speed transmissions because on top of the platforms there was no need for the high speed, with very little room to maneuver. If there is any serious obstacle the driver must slow down (except for the few who try to fly). The more obstacles, the fewer opportunities there are for the driver to use the fast speed...

One of my favorite tools for out-of-the-box thinking is to turn things around the other direction. In this case, you seem to be implying that the purpose of a second speed is to go faster. But it's just as reasonable to have a "normal" driving speed plus a second slow speed, used for extra torque when needed. Instead of a medium-speed robot that can switch into a higher gear to zip across the field quickly, consider a medium-speed robot that can switch into a lower gear to hold its ground or push others out of its way.

If the playing field is open, high speed tends to be an advantage. If the field is congested, pushing power tends to be an advantage. Both situations are well served by a shifting transmission.

[Brandon Holley]

I'm seeing a lot of talk here about the 2004 game...

Imagine the 2004 game....with 2 more robots on the field....MADNESS

The sides of those platforms would get quite crowded, and that was with only 4 bots around the field!



I have no idea what relevance this has with the rest of the thread.

[Greg Needel]

Originally Posted by Brandon Holley

I'm seeing a lot of talk here about the 2004 game...

Imagine the 2004 game....with 2 more robots on the field....MADNESS

The sides of those platforms would get quite crowded, and that was with only 4 bots around the field!



I have no idea what relevance this has with the rest of the thread.

Even better...think about 6 robots trying to hang at the same time...

[Greg Needel]

Originally Posted by Gabe

I know FIRST is itching for an obstacle field, so plan accordingly.

State your source.

[Gabe]

Originally Posted by Greg Needel

State your source.

No outside source, just a gut feeling after looking at the history of challenges over the years. Just imagine how much more trouble driving would be with an obstacle as simple as a 2 by 4 laid flat on the ground.

[Lil' Lavery]

Originally Posted by Gabe

No outside source, just a gut feeling after looking at the history of challenges over the years. Just imagine how much more trouble driving would be with an obstacle as simple as a 2 by 4 laid flat on the ground.

Yes, but there were never more than 4 robots on the field at a time during that history of previous challenges. If alliances remain 3v3 (+), I don't see a 2000 hill/trough structure, 2001/2003 divider bar, 2003 ramp, or 2004 platform coming back. The 2005 goals and 2007 rack were plenty impeding enough with 6 robots on the field.

[114Klutz]

Originally Posted by Rex114

I think that if FIRST keeps pumping out games with the same relatively flat field with maximum of 30? inclines to climb, you will see more and more 2 speeds. There just isn't a challenge for teams to design anything besides a basic 4"-8" diameter, 4 or 6 wheel drive train. Its related to the arms race thread, but on a broader scale. Most teams wont try to make a V6 or anything like that, but with all the previous designs out there, a 2 speed isn't that much of a stretch for any semi-experienced team.

And there are teams out there that have almost reached perfection as far as 2 speeds go. 254/968 has the most elegant and thought out drive train I have ever seen. And it helps that they have had at least since 2004 to work out their design. I'm not quite sure if you can get any better than a 1.4 pound 2 speed gearbox (great job Travis btw) and I would doubt their entire drive train came out to be over 35 pounds. Thats 85 pounds to do whatever else you want to do with the robot! Being the one who is always working on arms/manipulators, it would be nice to be able to make something without having to worry if the drive train is gonna take up all of the robots weight.

In short, yes, as long as games continue to have fairly repetitive field layouts, 2 speed will become better and popular-er (is that a word? )

Mike C.

More popular. But indeed, the issue with two speed gearboxes is now not mechanical skill or cost, both of them are now remedied by AndyMark.

The question is now, is it actually needed? For example, this year showed little advantage to be gained by using a two speed gearbox. The field was not open, and the two sides next to the rack could easily be blocked by opposing machines. I do not believe it was worth the time and weight to implement a two speed gearbox.

The second issue is - how easy is the gearbox to implement? Manpower is a significant issue. While AndyMarks are rather simple to implement - it may require the addition of subsystems, such as pneumatics, which might not be viable if time is short. Custom gearboxes are notorious in this respect - ours went over the deadline significantly. While this was fixed, it took time away from some other projects.

My personal preference has always been to eschew shifting - because it simply is complicated and time consuming. However, if two speeds actually does give a substantial advantage in game - then by all means, go for it.

[AdamHeard]

Originally Posted by 114Klutz

The question is now, is it actually needed? For example, this year showed little advantage to be gained by using a two speed gearbox. The field was not open, and the two sides next to the rack could easily be blocked by opposing machines. I do not believe it was worth the time and weight to implement a two speed gearbox.

I know several teams who would entirely disagree with you based on the success they had this year. I had to play defense first hand on 254/968 and 330 on many occasions... What made them stand out over other teams was their driver's ability to evade and maneuver in high gear, and resist pushing in low gear.

These are just first hand examples, I'm sure many other teams that were offensive robots can thank their success on the extra edge their drive gave them. 1114 and 1270 from curie are another two. Also, 45 and 1902 in Galileo used them well.

I think what is more important than perceived game environment is whether or not the driver can effectively utilize the advantage.

Usually the added cost in weight and work is minimal compared to not using them. I wish we had used shifters this year; They would actually weigh less than the 3 motor workaround we did and would be just about as complicated to install.