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falconmaster
08-01-2008, 00:21
[cdm-description=photo]29517[/cdm-description]

=Martin=Taylor=
08-01-2008, 00:23
Cool.

How'd they work? The transmissions I mean? Did it seem to shift quickly?

We've been concerned that the tiny servo may not be able to engage as quickly as a large piston.

billbo911
08-01-2008, 10:03
Very nice an effective design. A couple of Q's if you don't mind:
Does it use a 555 timer?
Can it be run off the 7.2 Vdc backup battery?
Have you tried it on a Victor?
Would you like to share the schematic? If so, this might make a very useful White Paper.

falconmaster
08-01-2008, 10:23
Cool.

How'd they work? The transmissions I mean? Did it seem to shift quickly?

We've been concerned that the tiny servo may not be able to engage as quickly as a large piston.

We hooked up a battery directly to the motors and then ran the tester, it can shift when you move it fast or slow, but keep in mind there is no load. It shifts smooth. It surprised us. we have used pistons in the past

falconmaster
08-01-2008, 10:26
Very nice an effective design. A couple of Q's if you don't mind:
Does it use a 555 timer?
Can it be run off the 7.2 Vdc backup battery?
Have you tried it on a Victor?
Would you like to share the schematic? If so, this might make a very useful White Paper.

Don't know what a 555 timer is

it can run off the 7.5 volt backup through the robot controller

The tester you can get at any model plane hobby shop or on line at
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXVK79&P=ML

Battery holder at radio shack

Could draw a schematic but I don't think you need it, "plug and play"

billbo911
08-01-2008, 10:42
The tester you can get at any model plane hobby shop or on line at
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXVK79&P=ML

Battery holder at radio shack

Could draw a schematic but I don't think you need it, "plug and play"

There I go assuming again!:mad:
For some reason, I thought you built it yourself.
Thanks for the reply.

BTW, a 555 timer is an electronic component.

MrForbes
08-01-2008, 10:47
Don't know what a 555 timer is

Ask Karen....

=Martin=Taylor=
08-01-2008, 11:14
We hooked up a battery directly to the motors and then ran the tester, it can shift when you move it fast or slow, but keep in mind there is no load. It shifts smooth. It surprised us. we have used pistons in the past

I am wondering what happens when your robot is stalled and tries to shift. In order for the dog to engage the gears must be turning. If you are in a standstill won't the servo shred itself to pieces trying to engage the dog?

falconmaster
08-01-2008, 11:29
The servo does not have enough torque to shred itself at least in the short term maybe over time, best to have a spare

falconmaster
08-01-2008, 11:34
The servo does not have enough torque to shred itself at least in the short term maybe over time, best to have a spare
sorry for the duplicate

Mike9966
22-01-2010, 16:05
Here's the Addy to a unit you can build yourself if you can program the pic chip.

http://www.rc-cam.com/servotst.htm

It looks pretty cool.

Mike


There I go assuming again!:mad:
For some reason, I thought you built it yourself.
Thanks for the reply.

BTW, a 555 timer is an electronic component.

Tom I
22-01-2010, 16:10
Have you tested the transmission under load? One thing my team found was when you tried shifting when actually driving, the servos tended to overheat and not shift into gear right away. For that reason, we used the pneumatic gear shifters and never had a single problem all year. But if it works, go for it, I love the tester!

vivek16
22-01-2010, 17:54
I agree, testing with no load is not incredibly realistic. If it works, it will save a few pounds though!

-Vivek

Chris is me
22-01-2010, 21:17
Are these shifters being paired with the mecanum drive being posted earlier?

Doug G
22-01-2010, 21:33
We found out in 2008, that we couldn't get the AndyMark servo shifter to work fast enough when driving. The pnuematic version was much more reliable and quicker. If you want to shift on the fly... go with the pnuematic. I know it is a pain to incorporate pnuematics if you don't use them elsewhere, but remember you can precharge some tanks and keep the compressor off the robot.

Galum
23-01-2010, 08:22
From what we’ve seen, on stall or other high loads the servo had problems shifting. Shifting without load was never the problem, take note we tried it with the gen1 am shifter and not the new super-shifter.