Problem with jaguar's "loss of servo link"

[Thundrio]

for the past couple days my team (a rookie team) have been trying to get our robot driving without success. both jaguars have slow orange lights blinking which we found to be a loss of servo link error. after looking into things we have found a few problems that might be the issue, and i would like some help figuring it out.

First I just want to make sure that the software is not the issue. if I open up the arcade motor control example program (in labview) and go up to the arrow and deploy it, isn't that all we need to control the jaguar for a test run?

Also we were looking at the power distribution diagram for this year, and we saw 12 volts of power connecting to both the 9201 serial ports on the cRIO from the power distribution panel. We also see power connecting from the 9472 port, but we do not have any of these connections. Are these needed? I have provided another picture of how our cRIO is set up.

A new problem happened today (apparently out of the blue) because when we turned the "robot" on one of the digital side cars started flashing a green light by the RSL input (near the power cable). This only happens on one of the jaguars, and we were wondering what it meant as we cant find any documentation on it.

also, we figured out that 5 volts of power should be coming out of the digital side cars pwm channel, because the jaguar needs that much to run.

thanks a lot in advance for your help.

[Alan Anderson]

You did read the How to Set Up Your Robot Control System guide, didn't you? Once you have everything powered that needs to be, then we can talk again about any remaining problems you have.

[Thundrio]

I did read it and Everything is powered/connected except for the Analog and Solenoid Breakouts, which a veteran team's mentor told us was not necessary right now (although it will later). are these needed to power the motors specifically? thanks

[PAR_WIG1350]

Have you ever reversed the polarity to the jaguars? If so, that BAD...

Also, make sure the servo jumpers on the digital sidecar are NOT installed, as these are only necessary for servos.

Good luck!

[Thundrio]

i dont think we have applied any kind of polarity to the jaguars.

[Alan Anderson]

Originally Posted by Thundrio

I did read it and Everything is powered/connected except for the Analog and Solenoid Breakouts, which a veteran team's mentor told us was not necessary right now (although it will later). are these needed to power the motors specifically? thanks

Motor power doesn't come through any of the cRIO modules or breakouts. However, you shouldn't be taking any shortcuts. The battery power going to the Analog Breakout on the module in cRIO slot 1 is absolutely required by the robot rules. Without it, the system won't be able to monitor battery voltage and the undervoltage shutdown won't function.

When you have the battery voltage displayed properly on the Driver Station, we'll work on whatever else might be wrong.

[Thundrio]

okay we hooked those up and we are still having the same problem.

[Thundrio]

please help as i have spent at least 15 hours on this one problem alone, and as the electrical and programming leader (with hardly any programming done, and not really any other programmers) i really need help to get this working so i can move on.

[Joe Ross]

Can you take a picture of your electronics board and wiring?

There are a number of things I can think of, any one of which could cause the problem.

You didn't enable the robot on the driver station
You didn't plug the PWM cables from the jaguar to the digital sidecar PWM ports
You didn't power the digital sidecar
The digital sidecar isn't plugged into the digital module in slot 4 of the cRIO
You have the PWM cables plugged in backwards. B is for black wire.
You have the PWM cables plugged into the wrong PWM ports on the digital sidecar.

The flash rate of the green LED next to the RSL may be a clue. What pattern is it flashing?

[Thundrio]

we have done all those things that you listed correctly. for the flashing led, after 20 seconds of powering on the robot, it starts flashing in no pattern, but if we hook the robot signal light up to it that starts flashing too, so we assume it is related to that. here are some pictures of our wiring.

https://picasaweb.google.com/lh/phot...t=d irectlink

https://picasaweb.google.com/lh/phot...t=d irectlink
ps, in this image you can see the second digital side car is not powered, that was temporary and is fixed now.

[Joe Ross]

Originally Posted by Thundrio

we have done all those things that you listed correctly. for the flashing led, after 20 seconds of powering on the robot, it starts flashing in no pattern, but if we hook the robot signal light up to it that starts flashing too, so we assume it is related to that.

How long are the flashes? .2 seconds off and .2 seconds on indicates no communication with the driver station.

[Thundrio]

all right i looked at it and it looks like its flashing at .2 intervals but im not sure. i checked the connection with both digital sidecars and the rsl indicator only flashes when the digital sidecar is connected to port 4 of the serial port, if its port 6 its fine, although i still get no connection to the jaguars.

here is a video of the flash in case you want to look at it. unfortunately i cant link you directly to the video (youtube is blocked at school), only my channel, but if its processed it should be easy to find.

thanks for help

http://www.youtube.com/user/12samn