if we switch out the driven gear to a 36t gear and made the driven sprocket 12t
the entire module can be shrunk by 2 holes and the ratio would be .66:1 torque and 1.8:1 speed which is perfect
we will probably make those changes and duplicate the other side on monday or tuesday ](http://www.youtube.com/watch?v=XGDps...ature=youtu.be)
you can clearly see the difference between the high torque and high speed difference
it is pretty awesome!
there are still small issues we have to fix but overall it was pretty successful
whats next: we will likely be fixing the minor “friction” issues the high speed mode is sometimes having issues with
we might just build a 3 speed transmission next
I forget who suggested this first, but try powering the planet carrier directly with the motor (so you don’t use the intermediate 36t gear).
The sun gear should be held in place by the 4 planets well enough so you don’t need the extra support.
Something you can do to get rid of the extra gear that drives the planet carrier is to change the green insert to a metal insert. Then split the shaft so the shaft connected to the output is not inserted into the metal insert. This way less space is consumed, however the ratio would be different. It would be more geared for speed. 1:1 instead of a 1:3 roughly
I was going to make something like this, but unfortunately we have limited pieces (my club has 5 ‘equal’ teams). I was only able to make one complete assembly (we don’t even have enough small gears, not to mention my team’s has slightly bent teeth = friction).
I would refrain from starting the trend of calling this a Taiwan Drive, but maybe that’s just me. Its more appropriate name, I believe would be a Planetary Drive. I don’t want to take credit away from 4194B, but names such as “NZ Bot” have always gotten a little on my nerves, although in that case it was generalizing the entire robot design for the most part, and here we are only talking about a drivetrain.
Now, if you were to copy the planetary system, as well as the differential system in which 4194B created, I think that may justify calling it a “Taiwan Drive”. However, example in the comment below, it causes some confusion to others, as they cannot simply look up on Google what a “Taiwan Drive” is.
Just a suggestion.
The drive “murdomeek” has created uses epicyclic (or “planetary”) gearing, with two inputs and one output, such that the direction of the two input motors determines the torque/speed of the output.
Although you cannot see it very well unless you go to the Picasa album they posted, all the hype over epicyclic drives has started because of the robot 4194B created, and their thread they have posted.
To see a nice animation made by jpearman which shows the general design everyone is using to build their epicyclic systems, click here.
today we tried making different planetary gears and somehow we ended up with a 14:1 ratio with one of the gearsets!
will post more pics tmrw and a more detailed explanation of what we were trying to do
@lego
ive thought about the “branding” thing but i think overall its just easier if everyone is familiar and uses the same terminology
remember the “6bar, 8bar, double-bar” argument about 6-bars when they first started getting popular?
people were all talking about the same thing, but the different terminology confused people in discussions
and with the “NZ” bot, even though many people came up with the same idea themselves, it was the NZ’s that made the design popular
also saying “NZ” is also faster to say “side intake rollers, 6bar, ramp” design
I think crediting the creators is important. The amount of innovation that 1107 has taken from 4194b’s original robot is enough to justify giving it its own name. Also, the name “Planetary Drive” could be applied to any drive that uses a planetary gearset. There are many, many ways other than this way that a planetary gearset could be used on a drive. The name needs to be more specific.
My only problem with the name “Taiwan Drive” is that this is not a drive but a transmission. It could be used somewhere other than the drive, although I admit that seems unlikely.
I can understand your irritation at the name “NZ bot”. The design was similar to yours, which of course was why you won the inspire award. I think this is a good moment to say congratulations :).
The “NZ bot” was also at least partially based on your robot (I would say more than partially except that 720p had a ramp on a chain linkage before you posted your design and the NZ teams could have copied him rather than you, just substituting the chain linkage for a 6-bar). In my opinion the credit for the robot belongs to the three teams responsible for its three main innovations: the 6-bar, the idea of using a ramp intake for Gateway, and the side sucker. Number one was AURA :D. Number two is what you guys usually get credit for. Legend has it that number 3, in New Zealand at least, was 720p.
It would be nice if everyone had known the story in more detail, though. Someone at Worlds accused AURA of having “Copied 24c” which made us sad :(.
In my opinion a thread has to be made exclusively about this. Giving credit where it is due is super important, especially as SO many people (myself included) “borrowed” some of these design features. I think some credit also has to be given to 2915A, who was the first (to my knowledge) to COMPETE with a form of side intake, though it was very different to the type of side intake that became popular, which I THINK can be credited to 720p, though all of my knowledge about this is just stuff I’ve heard. I think it would be cool if we could get the story straight and make a big thread to credit ALL the people who contributed to what was probably the most widely used design this season.
So I agree with Jordan that it is useful for people wanting to learn about a system to be able to use a name that they could use in google and get results from elsewhere (I know that the 1 st google result is this thread, but people have probably seen this if they are interested in the Taiwan transmission). I also agree that it will irritate a lot of people who may have also of thought of the idea and yet the credit is going to a different team, as we saw with the whole “NZ design” name. So I agree in that sense but then also credit should be given where credit is due, and no one will have probably known about this as much if 4194B hadn’t made it so popular with their amazing robot.
Its one of those things that people won’t always agree with, and I am sure people will call it what they want, and there isn’t much that can be done to change that. Maybe I’m wrong, but I would have thought that a large majority of people will understand what you are meaning by ‘Taiwan drive/transmission’, ‘Planetary Differential drive’ etc. And at the end of the day, if someone doesn’t know what you are talking about, there’s no harm in asking, is there?
But getting back on topic…
Murdomeek, you have an awesome little robot there.
Do you have any other plans for this, or is it just for testing/playing around with the transmission?
hmm there are still some little “friciton” issues that have to be fixed
but we may not be entirely comfortable in dunking the entire module in a bucket of grease just yet…
we are thinking of using this type of drive for a competition robot, the ratio is .6 and 2.5 respectively
idealy, it would be .6, 1, 2
but we need to mess around more and see if we can figure out a 3speed transmission
i think 6HS drive would be doable in college
Yes, the New Zealand design was based quite a lot on 24c’s design. In fact, our first Free Range robot of the season was pretty much the same as 24c’s. See this image.
Maybe Max (720p) could clear this up (he was the first with the “NZ design” in New Zealand), but in my opinion, the intake 2915A was in some ways similar (it had horizontal rollers), but I don’t honestly think the common horizontal rollers were based on 2915A’s intake. Again, I could be wrong, just my thoughts.
If you’re worred about friction, try making your system similar to this one below. Perhaps your problem is due to gears having slightly bent teeth, like my plastic 12-teeth gears are. This system is very easy to turn.
Stephen’s planetary is actually the optimum method, the only thing I would change from stephens is the HS gears in the center. replacing them would lower the footprint of the planetaries, as well as decreasing friction due to lower surface area.
It’s also recommended to place the shaft collars holding the planets in place on the inside, sandwiched between the two 60 tooth HS gears. This makes it easy to maintain the planetaries.
Thanks for the complements
The nice thing about this one is that it fits exactly between two bars in a chassis. I didn’t use the low-strength gears because like I stated before, one of my 12-tooth gears has a tooth ever-so-slight bend, which causes the system to have trouble getting past that tooth.
It’s also notable to mention that the proper rotation of the 6-tooth sprockets is necessary. Each sprocket is rotated 90 degrees from its neighbor’s orientation in this design, as the spacers provide enough tension on the chain for slack (low friction!) without slip.
