The perfect 2 speed Transmission..... features...

[Salik Syed]

what are some things to make a nice 2 speed transmission into a perfect one... like u know common problems with crappily designed 2 speeders.... also some nice addons you can think of to make it better.... all i could really think of was to add wheel encoders and a ratcheting tensioner on the transmission, and to have the pneumatic screw directly into the tranny instead of like on some ghetto rigged ubolt and to use 2 PNEUMatics instead of one big one going across..

[sanddrag]

Some of the below may apply to transmissions of any type

Fast shifting on the fly.
The correct amount of backlash.
Along with the above, very very little room to be between gears, never a possiblity of both gears engaged at once.
Proper alignment.
No loads in undersirable directions (ie side loads)
Gears and shafts poperly spaced and captured - This one is very important. If you don't know how to do it or what I mean by that, we'll disuss it.
Both sides shifting at the same time.
All timed motors always spinning in the advanced direction while the robot is moving forward.
High durability.
Low maintainance.

Most of all, the driver nor software should not have to take any precausions when driving or shifting whatsoever. The transmission should perform sucessfully by its own mechanical doing no matter what the driver's input is. The mechanics of the transmission need to be robust enough to downshift at full speed and shift while switching between forward and reverse and shift up and down multiple times in a row very quickly and shift while turning clibming, etc any crazy thing you can think of (ie. drive into a wall)

The forces and situations that robots encounter in finals rounds I'm sure are far beyond any testing most teams do. Good drivers know the limits of their machines, but great drivers have machines with no limits. I say as soon as your robot runs (during the build period) you should run it hard. Put it through every torture imaginable. Then by the time ship comes, you'll hpefully have it made bulletproof.

[Joe Ross]

low weight

[Tom Bottiglieri]

easy enough to build in 6 weeks

[Kyle Love]

One word...reliable!

-Kyle

[greencactus3]

Originally Posted by Kyle45

One word...reliable!

-Kyle

make that indestructible!

[Salik Syed]

Simple... true that...>! infact last year ours was pretty reliable but stuff kept breaking like chain and stuff!! arrrghhh....
here is a picture of the tranny for 2005:
it has a FP and CHip....
the only thing i'm reallly worried about is using the skinny 1/8" plate shifting fork i don't think it should be too much of a problem....
i was really hoping to put the Output sprocket inside the transmission but that wasn't possible... or at least practical compared to teh current config..

[Salik Syed]

by gears properly spaced do you mean simply add the pitch radii and for the shafts secured you mean like collars and whatnot.... or is it something else?

if we build this thing it will be probably the hardest one to build so far.... esp considering the 1/4 " shafts, tiny parts, and the tight squeeze, our first 2 spd tranny was like 12X4X6 inches!!!! this one is like 4X4X2! (actually smaller if you don't count the extra empty plate for mounting) i mean for this thing i will have to countersink holes etc... so that screws don't hit gears etc etc... while on the last one we'd just move the gear forward some ... they were 20 pitch gears too! and like 1/2" face width ...

[Tyler 783]

Never Use the drill transmitions. I know that they are more then likely not going to be included in the kit this year I think a way to make a good trasmition into a great one is to run the motors into the gearbox directly without having anything inbetween (like a preassembled drill transmition) because two years ago our gearbox (a two speed shift on the fly) was almost perfect except for the fact that we would blow a drill transmition almost everyround. I got so good at fixing the drill transmitions that I could reasemble them blindfolded!

[JVN]

Originally Posted by Tyler 783

Never Use the drill transmitions...

Jeez folks.. what is with all the drill bashing lately?

I know MANY teams (mine included) that used the drill transmissions las year with NO problems.

That's right, we ran a drill motor/tranny combo all season last year powering our arm shoulder joint (under SERIOUS shock loads) with no problems. None at all. The original tranny is still in that robot today.

Everytime someone posts on these forums "never use the drill transmission! They blow up all the time! We destroyed 80 kabillion of them!"
I wonder: "What the HECK are you guys doing to that poor gearbox?"

Personally I hope we see it back in the kit.
(I know everyone thinks FIRST has ruled them out, but I'm still waiting for the OFFICIAL confirmation, not this speculation stuff, that they're not coming back in 2005.) The drill and tranny (when not used for drive) make an EXCELLENT high powered mechanism motor. Lots of power, lots of reduction, small package.

Seriously,
3 competitions, lots of severe shock loading, no problems.
What are you guys doing wrong?
What am I doing right?

John

[Joe Matt]

Heck John, we have used two drills for a two drill transmission the past two years, and we won two regionals with it!

I love the drills, they are small, lock when not moving, and just great motors.

[Cory]

Originally Posted by JVN

Jeez folks.. what is with all the drill bashing lately?

I know MANY teams (mine included) that used the drill transmissions las year with NO problems.

That's right, we ran a drill motor/tranny combo all season last year powering our arm shoulder joint (under SERIOUS shock loads) with no problems. None at all. The original tranny is still in that robot today.

Everytime someone posts on these forums "never use the drill transmission! They blow up all the time! We destroyed 80 kabillion of them!"
I wonder: "What the HECK are you guys doing to that poor gearbox?"

Personally I hope we see it back in the kit.
(I know everyone thinks FIRST has ruled them out, but I'm still waiting for the OFFICIAL confirmation, not this speculation stuff, that they're not coming back in 2005.) The drill and tranny (when not used for drive) make an EXCELLENT high powered mechanism motor. Lots of power, lots of reduction, small package.

Seriously,
3 competitions, lots of severe shock loading, no problems.
What are you guys doing wrong?
What am I doing right?

John

Thoroughly agree with you... we used the drills with the transmisions in 2003, 2002, and 2001 with no problems. I remember asking the same question as you last year--what are all these people doing so wrong that they can't use the transmissions?

I'd love to see the drill and it's transmission in the kit this year as well.

[Doug G]

Originally Posted by JVN

Jeez folks.. what is with all the drill bashing lately?

I know MANY teams (mine included) that used the drill transmissions las year with NO problems.
....
Seriously,
3 competitions, lots of severe shock loading, no problems.
What are you guys doing wrong?
What am I doing right?

John

You were probably doing it right. I saw many newer teams last year encounter problems because they didn't know all the tricks... Tearing the transmission apart and removing the two pins (for coasting) or zip-tie / tape the spring clips in for the shifter or building you own mounts that work reliably. I remember using the plastic mounts in 2003; if you installed them just right, you're golden, but if you switched the rear and front mount or somehow didn't line them up perfectly, your transmission loosened up and the shifter disengaged. Oh yea, what about the back of the drill motor, how many students accidently dropped them from a height of 2" and had the plastic brush clip thing break. Very frustrating for some teams.

Will they be back for 2005? Not sure, but I'm with a lot of people in saying that we wouldn't be surprised if they're not back, and if they do come back I bet they're a slightly different model (maybe the back of the motor is made sturdier!)

[Tyler 783]

Originally Posted by JVN

Jeez folks.. what is with all the drill bashing lately?

I know MANY teams (mine included) that used the drill transmissions las year with NO problems.

That's right, we ran a drill motor/tranny combo all season last year powering our arm shoulder joint (under SERIOUS shock loads) with no problems. None at all. The original tranny is still in that robot today.

Everytime someone posts on these forums "never use the drill transmission! They blow up all the time! We destroyed 80 kabillion of them!"
I wonder: "What the HECK are you guys doing to that poor gearbox?"

Personally I hope we see it back in the kit.
(I know everyone thinks FIRST has ruled them out, but I'm still waiting for the OFFICIAL confirmation, not this speculation stuff, that they're not coming back in 2005.) The drill and tranny (when not used for drive) make an EXCELLENT high powered mechanism motor. Lots of power, lots of reduction, small package.

Seriously,
3 competitions, lots of severe shock loading, no problems.
What are you guys doing wrong?
What am I doing right?

John

Yes I know that some teams had no problems with them that is because 2 years ago there was a mass defect in the coupler assembly line and I know my team and many other teams got defective couplers which where not drilled and taped straight. This caused the drill transmissions to torque up and down sheering the casing. This was the problem I know my team and many other's had. Because of this there where some people who got good couplers before the defect in the line happened. But those are few and far between. I have no problems with the actual drill motor or actually the transmission but those coupler's. And since you can't attach the drill transmission easily to a shaft without one it makes the drill transmission almost useless.

[Doug G]

Originally Posted by Salik Syed

Simple... true that...>! infact last year ours was pretty reliable but stuff kept breaking like chain and stuff!! arrrghhh....
here is a picture of the tranny for 2005:
it has a FP and CHip....
the only thing i'm reallly worried about is using the skinny 1/8" plate shifting fork i don't think it should be too much of a problem....
i was really hoping to put the Output sprocket inside the transmission but that wasn't possible... or at least practical compared to teh current config..

Well let's start with the FP mount.. You need to secure it in two places, otherwise it's pinion will not fully engage the other gear. The one mount you do have, how would it secure to the transmission plates? (if those plates are 3/16", will we be able to drill and tap them out for #6-32 screws, hmm?)

The shifter fork could be made out of 3/16 angle and if kept short enough, should work OK. I guess this means the internal shifting rod (Andy Baker style) is being abandon due to the reduced space next to the Chip motor?

The pnuematic cylinder is backwards. Easy fix.

Where's the pinion on the Chip? It's not that large blue gear is it!! Is it below it?

And finally, how did you get inventor to do the 701 on the side of the transmission?