New AndyMark Shifters!

[Gabe]

Hopefully this thread doesn't exist yet...

AndyMark has new servo shifting transmission. Gotta hand it to them for eliminating the need for a pneumatic system to shift. This is awesome news!!

http://andymark.biz/products.htm

Thank you AndyMark! :D :D :D

http://andymark.biz/products/am-servo-shifter/AM-Servo-Shifter_inside1.jpg

[Peter Matteson]

No my question for Andy and Mark is, will there be an upgrade kit available to convert a spare gen 2 to a servo shift?

[Andy Baker]

No my question for Andy and Mark is, will there be an upgrade kit available to convert a spare gen 2 to a servo shift?

Yes, we will have one ready. It's just not on the site yet. The tricky part to converting from pneumatic to servo shift would be swapping out the small "shift shaft" that is connected to the dog gear by a 3/32"x1" roll pin. If you're good at removing that roll pin, then it will be easy.

Andy B.


ps... man, Gabe, you're quick. This was put on our website at midnight last night.

[Billfred]

This. Is. Awesome.

Neither of my teams have used pneumatics (and that's with five robots between them), and I've always been sort of leery about hooking it all up just for one function. I've seen servo-shift mods for them before (343 had one made in 2005, although I don't think it was on the actual robot), but it's awesome to be able to get one right off the shelf that could be used for several years so long as the FIRST rules don't change.

I guess this is how Andy Baker's placebo won the Midwest Regional. ;)

Is anyone else getting a 404 for the Gifts page?

[Peter Matteson]

[QUOTE=Andy Baker]Yes, we will have one ready. It's just not on the site yet. The tricky part to converting from pneumatic to servo shift would be swapping out the small "shift shaft" that is connected to the dog gear by a 3/32"x1" roll pin. If you're good at removing that roll pin, then it will be easy.
[QUOTE]

Shouldn't be a problem. When we built dog shifters for the first time in '04 it took a few attempts to get things right :o so we have experence.

I'm getting the 404 on gifts also, but I got my t-shirt already. Just another reason to drive halfway across the country to go to IRI.

[Jeremiah H]

Looks great. We're going to try to implement such a system on our custom gearboxes, so I have a couple performance questions:
-How long does it take to shift? (and what is the throw in that time period?-ours needs about 1 1/2" travel in as little time as possible)
-I don't know a lot about servos, so could a longer arm on the servo be used to decrease shift time? Would the servo be strong enough?
-How long could said arm be before the servo wouldn't have enough power to shift? Thanks. -JH

[Justin M.]

Looks great.

Two years ago we built and installed custom servo shifting gearboxes with the DeWalt motors and casings in our robot...so much torque that it bent the chassis - we had to switch out for the standard FIRST gearboxes with CIM's.

[Andy Baker]

Looks great. We're going to try to implement such a system on our custom gearboxes, so I have a couple performance questions:
-How long does it take to shift? (and what is the throw in that time period?-ours needs about 1 1/2" travel in as little time as possible)
-I don't know a lot about servos, so could a longer arm on the servo be used to decrease shift time? Would the servo be strong enough?
-How long could said arm be before the servo wouldn't have enough power to shift? Thanks. -JH

The Acroname page for this product (http://www.acroname.com/robotics/parts/R84-HS-322HD.html) gives good specs:
60 degrees of throw in 0.19 seconds
41.6 oz-in of torque.

The servo arm has about 3/4" distance from the center of rotation of the servo out to the shift shaft. So, this translates into 55.4 ounces or ~3.46 lbs of force. This force is adequate, but it definitely does not give an immediate shift like a pneumatic cylinder does. If the arm was made longer, then the force of the servo arm would be less. I suggest not making your arm any longer.

As for shift time, the 0.19 seconds is the length of time it takes for that arm to swing 60 degrees. However, don't expect your gearbox to switch in exactly that amount of time. The first 0.1 seconds will remove the dog gear from where it was mated and then it will try to engage the other gear. Since the arm is pushing with only 3.4 lbs. of force, the engagement will not happen as quickly as it would if it was being pushed by 20 lbs from a 3/4" bore air cylinder. It may take longer (up to a full second or so) for that shifting dog gear to line up and slip into the mating dogs on the other gear.

Like any engineering decision, there are trade-offs here. For the benefit of giving up pneumatics, you are paying the price in having a lower force shifter that may take longer to engage and complete a shift.

Looks great.

Two years ago we built and installed custom servo shifting gearboxes with the DeWalt motors and casings in our robot...so much torque that it bent the chassis - we had to switch out for the standard FIRST gearboxes with CIM's.

Yep, servo shifters have been utilized for a few years. We (team 45) had one in 1999 and then decided to publish a Servo Shifting Gearbox whitepaper (http://www.chiefdelphi.com/media/papers/1306) in the summer of 2000.

Back then, the gearbox had to stop before the servo would shift. With the above design, the dog gear can just slam back and forth all day between the two gears, not caring what the motor speed is. Today's robot drivers have it pretty good.

Is anyone else getting a 404 for the Gifts page?

Yep... me too. grrr.


Andy B.

[Stephen Kowski]

(343 had one made in 2005, although I don't think it was on the actual robot)

http://jskowski.com/gallery/ucf2005/CIMG0039 (sry for the blurriness)
http://jskowski.com/gallery/palm2005/P1010138

They were on there in the UCF Regional and Palmetto Regional in 2k5, the only difference was in Palmetto they switched out the gold steel AM plates and replaced them with the aluminum ones in the photos....a nice addition to the product line Andy....

[David Kelly]

Is anyone else getting a 404 for the Gifts page?





Yep... me too. grrr.


Andy B.


Yeah, thats my fault. I'll get that fixed tonight.

[Jonathan Norris]

This is awesome.... The only reason we had pneumatics on our robot last year was for the shifting transmission. This will save those precious few pounds :D, especially when you are 25 pounds over weight like we were :ahh:. We will definitely be grabbing a few of these in the near future.

[Travis Hoffman]

These look great, Andy.


One question - have you done any long term testing to see how the servo and the plastic components hold up during extended (and aggressive) use?

Say....running the transmission motors off a power supply for 8 hours while programming the servo to shift at 10 second intervals and seeing if everything is still in one piece and not melted/stripped/on fire the next morning? You know....fun testing like that. :p

8 hours operating time x (60 minutes per hour) x (60 seconds per minute) x (1 shift per 10 seconds) = 2880 shifts.

48 matches per season (worst case guess) * 20 shifts per match (again worst case guess) = 960 shifts.

I think 8 hours of continuous testing should cover it. :D

[M. Mellott]

One question - have you done any long term testing to see how the servo and the plastic components hold up during extended use?

Don't worry, Trav--we're going to find out for ourselves. Just placed the order for a pair of 'em!! :cool:

[Conor Ryan]

Finally! I love the idea of a servo shifter, and it's great that more people will get to see why I love them now! Say good by to your heavy pneumatics! Its a 10 Dollar upgrade that is money well spent (It's marked currently for $340)

Andy and Mark, what do you see as the disadvantages and advantages of the Servo shifter over the Gen. 2 Pneumatic Shifters?


Difficult question aside, great work! I can't wait to see them on a 2007 Water Game robot! (Are the gearboxes available waterproofed yet?)

[Alex Cormier]

*mouth watering good*

Looks sweet and im sure they work even better.

[Cory]

Finally! I love the idea of a servo shifter, and it's great that more people will get to see why I love them now! Say good by to your heavy pneumatics! Its a 10 Dollar upgrade that is money well spent (It's marked currently for $340)

Andy and Mark, what do you see as the disadvantages and advantages of the Servo shifter over the Gen. 2 Pneumatic Shifters?


Difficult question aside, great work! I can't wait to see them on a 2007 Water Game robot! (Are the gearboxes available waterproofed yet?)

gears won't care if theyre running underwater... the electronics will ;)

[Lil' Lavery]

8 hours operating time x (60 minutes per hour) x (60 seconds per minute) x (1 shift per 10 seconds) = 2880 shifts.

48 matches per season (worst case guess) * 20 shifts per match (again worst case guess) = 960 shifts.
Your match estimate is pretty low if a team attends multiple off-season competitions.
25 played 50 matches through Regionals and Championship (but that's counting 7 Newton elim matches, and 5 Einstein matches), and attended PARC, Monty, and IRI (and still has Brunswick Eruption). They probably have played around 85-90+ matches. But they represent a very small portion of teams.
20 shifts per match is probably a little high though (116 would typically only shift around 4 or 5 times a match, at most, when we used a 2 speed). So, your estimate probably isn't that far off.

[thefro526]

the new transmissions look great and look as if they'd be easier to use

Mecanum wheels+ (4) 2 speed transmissions.......... :)

[dubious elise]

I can't even lie, the sight of them absolutely made my day!

[techtiger1]

AndyMark does it again, you guys are the epitome of what engineers should be about, redesigning and perfection of a system/product. I also have to totally agree what Eliese said above seeing those things made my day indeed. Looks amazing, servo shifting and I am sure function even better then they look. Nice job to the whole AndyMark crew. Keep making SHIFT happen guys :) .

-Drew

[ChuckDickerson]

Yes, we will have one ready. It's just not on the site yet. The tricky part to converting from pneumatic to servo shift would be swapping out the small "shift shaft" that is connected to the dog gear by a 3/32"x1" roll pin. If you're good at removing that roll pin, then it will be easy.

Andy B.

Andy,

We have a spare Gen 1 AM Shifter sitting on the shelf. Will the "servo shift upgrade kit" work with the gen 1 shifter? If so what is in the "upgrade kit" and when will they be available for ordering?

[Gabe]

Their single speed transmissions are slightly different, too.
Check them out here:
http://andymark.biz/am-gearbox.htm

[efoote868]

Mecanum wheels+ (4) 2 speed transmissions.......... :)

= very heavy, and difficult to control. 1 second variation in shifting times is alot, and the change in wheel speeds would make your robot go 'crazy'

besides, Mecanum wheels don't get enough traction to need a low gear

[AdamHeard]

= very heavy, and difficult to control. 1 second variation in shifting times is alot, and the change in wheel speeds would make your robot go 'crazy'

besides, Mecanum wheels don't get enough traction to need a low gear

Let's just shoot down ideas and prevent innovation.

With the exception of the 1 second shift times, this idea isn't bad.

If faster shifters were used this wouldn't be a problem. A mecanum drive with a medium speed, and a really fast one would be a huge boost to mobility. Alhough current games seem to require pushing power and traction, none of us have any idea what next years game may be. Because of this, any idea right now can't be ruled out...

//end off topic

These shifters are nice innovation. Even with the 1 second shift time they could be very useful. Imagine the game next year requires moving very large heavy goals (I vaguely remember that for some reason....) and no defense. Then a high speed to drive around, and a low speed to move goals would be nice and the 1 second shift time wouldn't really have any negative effects.

[VEN]

Hey Guys. I have a question. I won't post a new thread though.

Is this gearbox the same dimensions as the FRC gearbox in the previous years (2005, 2006) and we made longer shafts for our FRC gearboxes which mount the same as the stock ones. How are the main shafts on these gearboxes? How are they different, if different from the ones on the FRC one?

Thanks


oops, I just saw there are sprockets, I wonder how that can work with out setup.
edit #2: I get how to hook it up now, but my other questions still stand

THANKS

[Conor Ryan]

Hey Guys. I have a question. I won't post a new thread though.

Is this gearbox the same dimensions as the FRC gearbox in the previous years (2005, 2006) and we made longer shafts for our FRC gearboxes which mount the same as the stock ones. How are the main shafts on these gearboxes? How are they different, if different from the ones on the FRC one?

It's a smaller gearbox (http://www.andymark.biz/am-0011.html), but has the same gear ratios (12.75:1). You can run either a:
FIRST kit CIM Motor (1 or 2)
AM Planetary gearbox (1 or 2)
or combination of above motorsThe Output shafts on these gearboxes are the same as the old kit gearboxes (0.5" Keyed) and the only difference real you would notice as a user, is that it isn't a cast aluminum box which doesn't take as much space up.

[Billfred]

It's a smaller gearbox (http://www.andymark.biz/am-0011.html), but has the same gear ratios (12.75:1). You can run either a:
FIRST kit CIM Motor (1 or 2)
AM Planetary gearbox (1 or 2)
or combination of above motorsThe Output shafts on these gearboxes are the same as the old kit gearboxes (0.5" Keyed) and the only difference real you would notice as a user, is that it isn't a cast aluminum box which doesn't take as much space up.Actually, the gear ratio is 12.75:1--and the output shafts are different (the old KOP unit was some metric figure close to, but not exactly, 5/8").

[EricLeifermann]

Yeah it is a cool design!

We came up with the same thing last year with our own modifications using the AndyMark transmissions. Servo shifting really helps with these transmissions.

[VEN]

Sorry Guys, I was talking abotu AM servo shifter GEN 2

[rustlerharv]

I designed and built servo shifters for the trannys last year with a hack saw and a drill press. Andy offered to buy the design at the Wisconsin regional but it looks like he developed his own. My design was a direct replacement for the pneumatic cylinder which would require no changing of anything.

[Gabe]

I designed and built servo shifters for the trannys last year with a hack saw and a drill press. Andy offered to buy the design at the Wisconsin regional but it looks like he developed his own. My design was a direct replacement for the pneumatic cylinder which would require no changing of anything.
Very cool! Do you have any pictures or CAD files to look at?

[rustlerharv]

as i said it was done with a hack saw and a drill press so CAD is out of the question and i didnt get any pics b4 it was torn apart so i can redo it for this year. ill try to get pics when its all done up with right since my team has real tools this year.

[Jonathan Norris]

Hey Guys. I have a question. I won't post a new thread though.

Is this gearbox the same dimensions as the FRC gearbox in the previous years (2005, 2006) and we made longer shafts for our FRC gearboxes which mount the same as the stock ones. How are the main shafts on these gearboxes? How are they different, if different from the ones on the FRC one?

Thanks


oops, I just saw there are sprockets, I wonder how that can work with out setup.
edit #2: I get how to hook it up now, but my other questions still stand

THANKS

Have a look at what we did last year for mounting the AM shifters, we made plates to mount them right between two of the wheels in our 6-wheel setup. We are doing something a bit different this year, but this setup worked well for us. It was simple and used the kit frame.

http://img297.imageshack.us/img297/9376/driveuo7.png