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View Full Version : Dewalt Transmission Crisis!


BurnFischer
14-02-2008, 15:14
Running 4 DeWalt transmissions on our robot, chain driven so that 2 of the transmissions are running 2 wheels. Unfortunately the victor's are setting the motors at 2 different speeds and tightening up one end, loostening up the other. When we run the 2 motors out of the same Victor, they are syncrod close enough that the wheels run, but when we stop it seems to lock up. Is there any way we can keep them being driven on through 1 chain, or should we split it and chain 1 wheel to 1 transmission/motor?

BurnFischer
14-02-2008, 15:15
And... if it's easier/ quicker to explain on the phone, (603)831-0447 will get me.

ajlapp
14-02-2008, 15:20
Check to see if you have your brakes on the victor........not sure if this would cause the problem, but its a good idea to remove them for drivetrains.

I believe no jumper on the brake means no braking feature.

billbo911
14-02-2008, 15:36
.... When we run the 2 motors out of the same Victor, they are syncrod close enough that the wheels run, but when we stop it seems to lock up. Is there any way we can keep them being driven on through 1 chain, or should we split it and chain 1 wheel to 1 transmission/motor?

1) Do not drive two motors from one Victor, it is specifically against the rules.

<R62> All electrical loads (motors, actuators, compressors) must be controlled by relay or PWM
output signals sent by the Robot Controller to an appropriate power regulating device
 Each CIM motor and Fisher-Price motors must be connected to one Victor speed
controller.2)You may drive two Victors, and therefore two motors, from one PWM output by using a Y cable. Driving two wheels from one transmission is quite common as is one wheel from each transmission. You may also want to calibrate your Victors, it may help keep them in sync.

BurnFischer
14-02-2008, 15:42
Driving them both from one Victor was to test whether or not it was an electrical, programming, or mechanical problem, we ruled out some stuff via running them through one victor. We already decided that once we sync the Victors they are going to just keep getting out of sync, and unless we have some way to constantly sync them... which we have yet to find a way, then syncing them doesn't work. Unfortunately... we're in a time crunch :yikes:

BurnFischer
14-02-2008, 15:55
We were, for the time running 2 victors off 1 PWM via y cable, but I read on another thread that it's more accurate to get them close to the same speed by calibrating it through running 1 victor per PWM

BurnFischer
14-02-2008, 21:31
we fixed it.... simple fix... backdrive pins were in.....

Gboehm
14-02-2008, 23:30
Check to see if you have your brakes on the victor........not sure if this would cause the problem, but its a good idea to remove them for drivetrains.

I believe no jumper on the brake means no braking feature.

Is this legal? and how do you do it? PM me

BurnFischer
15-02-2008, 14:54
You take the Jumpers off of the Victors

BurnFischer
15-02-2008, 15:02
It says nothing of the Jumpers in the rules...

Tristan Lall
15-02-2008, 15:34
You take the Jumpers off of the VictorsThere are actually two positions for the jumper; the leftmost two pins are for brake mode ("B") and the rightmost two are for coast mode ("C"). The jumper doesn't have to be removed entirely.

BurnFischer
16-02-2008, 00:14
True. Although it has been determined that when removed it sets it to default; Coasting. As unnecessary as it was to remove them.... /shrug, I have no clue =P I'm tired, it's in the final hours of... lets be honest, it's in the beginning hours of completion...