No subject

Tue Sep 21 18:39:23 UTC 2010

related to case 1. Can you have a look to see if dropped packets are
being reported by the ethercat master diagnostics?

Do these glitches occur even when the computers are under light load?
(Nothing running except robot.launch and the image viewers.)

If you are dropping packets every few seconds under light load, then
there may be a problem with your robot, and I would recommend opening
a support ticket.


On Thu, Sep 23, 2010 at 11:21 AM, Blaise Gassend
<blaise at> wrote:
> Hi Ulrich,
> I had a look at your bags, and I am noticing that there is a lot of
> oscillation in the image intensity. Auto-gain/exposure don't work well
> with alternating mode, and I would recommend switching them off.
>> Thomas R=FChr could help me out -i could not be in the lab today - and
>> recorded two bags with a synchronization node including the code changes=
>> proposed.
> Thanks for the bags. I see in the textured an interval of 3 seconds
> between flashes. Is that interval always the same, or is it different
> each time?
> Can you confirm that both cameras have problems at the same time?
> From the times at which the images are being sent, it looks like there
> may be an extra or missing trigger pulse. I'm going to try to
> reproduce this on one of our robots...
> I wonder if you could send me a bag of the following topics:
> /head_camera_trigger/waveform, /projector_trigger/waveform,
> /head_camera_trigger/trigger_narrow_stereo_both,
> /projector_trigger/on_time, /projector_trigger/off_time,
> /narrow_stereo/left/camera_info,
> /narrow_stereo_textured/left/camera_info,
> /narrow_stereo/right/camera_info,
> /narrow_stereo_textured/right/camera_info. You can make this one
> pretty long, say a minute, as it is a lot less data.
>> Do you think, that is solvable at all?
> Hard to know until we know what the problem is.
>> Can the projector be switched on and
>> off instead of being modulated?
> The projector cannot be turned on continuously because it would
> overheat. It is limited to 2 ms pulses (I forget the exact duty
> cycle). You can of course turn it off all the time, but I don't see
> how that would help you if you need alternating mode.
> One last thing: if you want to be able to filter out the images that
> are having trouble, I believe that you can use the image timestamp.
> The timestamps should be totally periodic when things are working
> well. When you get the bad images, the interval between two images
> will be different from what it usually is.
> Cheers,
> Blaise

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