Servo Failure

Question

Morning All

Today I upgraded to the latest software but now all my servos have stopped working. I rebooted both EZ and my laptop and rebuilt my servo controls but I get no response from any of my boards.

Has anyone encountered something similar?

Thanks,

Scott

DJ Sures · Answer

We'll get you running Answer these q's for me.. 1) What robot is it? A Revolution robot or custom? 2) How long has it been since you last used the robot? Could it be a wiring or power issue? 3) Are you connecting to the robot adhoc or client mode? 4) There are no issues connecting to the EZ-B? 5) Does the EZ-B make a chime when it boots up? 6) Is your robot using a custom project? If so, can you share it using the ATTACH FILE option on this forum. The servo modules of ARC's code hasn't been touched in a year - we'll figure out the issue with the robot.

Mulberry · Answer

We'll get you running Smile Answer these q's for me.. 1) What robot is it? A Revolution robot or custom? Custom. The system is only running servos. One to lift a bubble head via 1 EZ. One to activate two claws. 2) How long has it been since you last used the robot? Could it be a wiring or power issue? Last evening. 3) Are you connecting to the robot adhoc or client mode? Via the EZ network. 4) There are no issues connecting to the EZ-B? No. I get the chime and can connect. Blue light. 5) Does the EZ-B make a chime when it boots up? Yes 6) Is your robot using a custom project? If so, can you share it using the ATTACH FILE option on this forum. Currently its scattered across my work table but the attached image is the servo that was working last night. None of the settings were changed and again it was working last evening. I tested all my EZs (I have 4) and none will activate a servo. Either an EZ supplied one or other make. The servo modules of ARC's code hasn't been touched in a year - we'll figure out the issue with the robot.

DJ Sures · Answer

It's hard to tell but is your servo plugged in backward to the ez-b? Can you send a closer image of it connected to the ez-b please

Nomad 6R · Answer

dj looks like it. also not a good idea to strap wires whithout isolation straight on to , the spacers.

DJ Sures · Answer

Here's a video on connecting the servos. The darkest wire is GND - on the revolution servos, it's black. On your servos, it may be brown. The brown or black would connect to the black on the ez-b. Hope this solves the issue

Mulberry · Answer

Sorry for the delay. The servo connection was never broken (the same as when it was working last night). I think I'm going to delete the application and re-install. Thanks for catching the anchor strap Nomad eek D. Scott

DJ Sures · Answer

Let us know what you find

CardboardHacker · Answer

Sounds like an ARC issue if you haven't changed the robot at all.

DJ Sures · Answer

@TechnoPro, there's no issues with ARC. From the image it appears the servo is connected backward.

Dunning-Kruger · Answer

Maybe @Mulberry changed board #s, so maybe that's why the servo isn't working? Just a guess...

DJ Sures · Answer

Or, the servo is plugged in backward as the photo shows

Dunning-Kruger · Answer

@DJ, I agree it does really look like it from the pic... But he does claim he never unplugged the servo between tests..... I was thinking he may of connected from another board # than he did the night before.... ?

Mulberry · Answer

Part of my problem has been resolved. I was using two, 3 foot long servo cables to connect my claws to the board. I tried playing with the connections but no signal. So then I decided to try a direct connection without them and voila it worked. These were EBay purchases so lesson learned. Now I just need to find extended cables that are compatible because I need about 3 feet to accommodate my actuator arm movement.

My heavy duty servo still isn't working. I've tried turning the connector as well as different ports but nada. Could be I've damaged this one as well (3 and counting).

Scott

Nomad 6R · Answer

mulberry can you use these,they come from chop here. extention cable

thetechguru · Answer

Quote:My heavy duty servo still isn't working. I've tried turning the connector as well as different ports but nad If you had it plugged in backwards, very likely the servo circuit board is fried. Most do not have diodes to protect from reverse polarity. Alan

Nomad 6R · Answer

alan i did one time same fault and indeed the servo was fried. good thing they dont cost much.better a servo then a ezbv4.

Mulberry · Answer

Thanks Nomad. I'll check them out. The ones I originally used had a funny insulated block mid-way down. No idea why and they worked previously. I'm notorious for blowing circuits. An expensive hobby but I'm learning. Alan I have a growing pile of dead servos I plan on using for an art project :-) D. Scott

thetechguru · Answer

In general, when servos blow, it is the circuit board but not the motor, so you might be able to re-use the motors with cheap H-bridges, or as replacement parts on the rare occasions when a motor rather than a circuit board blows out. But yeah, I have seen my share of expensive blue magic smoke in this hobby.... Alan

Nomad 6R · Answer

i only by here my parts.then am sure i got the wright ones, and warenty just incase. my first bioloid i burn 10 servo's in one download,so your not alone. but it was also the fault off the seller,he was not annest man, and i say this whithout saying what he really was. i always say,the more you break the more you learn.

DJ Sures · Answer

The three wire cable if servos prevents them from blowing when plugged in backwards. You'll never damage a servo by connecting it backward. The ezb also has isolation resistors on the io to prevent backward servos from damaging the ezb. If the servo doesn't work, it's been used and abused. Which is quite common for custom built robots. We're always trying to lift too much weight

thetechguru · Answer

DJ, that statement contradicts real life experience. I have two blown servos and the only abuse was plugging them in wrong.

Mulberry · Answer

Problem resolved on the servo. I severed the wiring close to the servo, replaced it and the signal connected. I must have damaged it. D. Scott

Nomad 6R · Answer

mulberry great find.

Dave Schulpius · Answer

Nice work! Little things like that are hard to find. When trouble shooting i always start with a simple voltage or continuity check to see it the power is getting from point A to B. You would be amazed how often that this is the problem.

Mulberry

Upgrade to ARC Pro

Quote: