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View Full Version : pic: 2 Speed Vex Transmission


cire
20-03-2006, 10:52
[cdm-description=photo]23938[/cdm-description]

sburro
20-03-2006, 10:55
Thread created automatically to discuss this image in CD-Media.

http://www.chiefdelphi.com/media/img/c5e/c5efb9473f1778728d6cc88a3634719e_m.jpg (http://www.chiefdelphi.com/media/photos/23938?)
I like the transmission and think the concept is nice for a VEX bot but if you were to bring it to a FRC comp, I see too many gears binding and breaking. I think you would have to shift it not on the fly. This is the only problem I see.

cire
20-03-2006, 12:56
I like the transmission and think the concept is nice for a VEX bot but if you were to bring it to a FRC comp, I see too many gears binding and breaking. I think you would have to shift it not on the fly. This is the only problem I see.

The tranmission works great actualy, though you are right about the gears breaking and binding. Its only a matter of time before they break, I actuly found some plastic shavings that fell off of it. Im probably going to rebuild it so it has at least 2 gears in contact together all the time so its a little more robust.

By the way, it HAS to shift on the fly, when the gears are rotating it helps mesh them together.

sanddrag
20-03-2006, 14:03
Looks good. Although the small gear on the bottom left looks like it is positioned too fr to the left.

doukjin
10-04-2006, 20:03
I like the transmission and think the concept is nice for a VEX bot but if you were to bring it to a FRC comp, I see too many gears binding and breaking. I think you would have to shift it not on the fly. This is the only problem I see.

yayy plastic gears :D

ForgottenSalad
10-04-2006, 20:06
Just curious, what did you use to convert the servo to linear motion?

ICE MAN
10-04-2006, 20:48
Thats insane. My FRC team is still trying to complte a 2 speed for our first robot and here you guys have made a 2 speed for the vex. well we better hurry or else everyone will be blowing us away with speed! :D

Arkorobotics
11-04-2006, 01:44
I am planning on making a really cool version of that just with the new Vex Pneumatics :D

cire
16-04-2006, 22:19
Just curious, what did you use to convert the servo to linear motion?
a lock bar at the end of the shaft coming from the servo is attached to a piece of metal which is being held between 2 shaft colars, when they servo moves it pulls the piece of metal and the whole shaft with it. It had a problem with jamming occasionaly though so i redesigned it, which you can see posted here:

http://www.chiefdelphi.com/media/photos/24522

techen 5
18-05-2006, 22:21
I like the transmission and think the concept is nice for a VEX bot but if you were to bring it to a FRC comp, I see too many gears binding and breaking. I think you would have to shift it not on the fly. This is the only problem I see.
what are your gear ratios for each transmission level and could up send me more pictures from different angles of your 2 speed vex transmission

Lil' Lavery
20-05-2006, 15:17
a 116 alumnus is actually building a 4-speed vex tranny. Of course, it alone is too large for the FVC size requirements and recquires all 8 pwm outputs on the controller for just one. But then again, it also geared to theoretically have an output speed of 60 mph with one of the knobby wheels (although I doubt it would have enough torque to overcome static friction :rolleyes: )

lukevanoort
20-05-2006, 18:56
This inspired me to design my own two speed Vex tranny. I simplified to two shafts (<-- kudos if you figure out how) and started building it, but I never finished. Maybe I'll take one of our Vex kits home and finish it under the guise of making an example to introduce the newbies to advanced mechanisms.

nonother
20-05-2006, 21:14
a lock bar at the end of the shaft coming from the servo is attached to a piece of metal which is being held between 2 shaft colars, when they servo moves it pulls the piece of metal and the whole shaft with it. It had a problem with jamming occasionaly though so i redesigned it, which you can see posted here:

http://www.chiefdelphi.com/media/photos/24522

Your new design definetly looks more reliable but I noticed it used a spring. Since a spring isn't a Vex part would that make it not competition legal? Nonetheless awesome job.