Hello everybody,
we broke recently two ZED cameras, the Stereolabs team told us that we damaged the PCB of the cameras.
They also told us to pay attention to electrostatic shock, overvoltage,…
We have no clue about the origin of these breakdowns the only noticeable fact is that the camera gets warmer on the TX1 then on a standard laptop.
We use the ZED camera in a standard office environment over a clean desktop.
As I already reported, we use the ZED camera mainly connected to a NVIDIA Jetson TX1 with JetPack 2.3.1 .
The USB3 port of this board is also currently used with a realsense R200 without any problem.
We use the ZED camera along with the zed ros wrapper that you provide on your website
For sake of completeness, we applied the kernel patch which is available here http://www.jetsonhacks.com in order to make the TX1 board working also with the realsense.
Do anyone have any clue on what maybe the cause and how we can solve this problem?
Thanks in advance!
USB provides a standardized 5V…max current is higher on USB3 than on USB2, but voltage is not configurable. Additionally, so far as I know Jetsons and any USB port contain ESD protection as well. If the camera is connected to a HUB then the HUB could have issues with a particular port, especially if the camera is bus powered (you could check the 5V pins on any port connector you’ve used to see if it is still 5V). If the camera is self-powered then the 5V bus lines don’t even matter (some self-powered device have the option to be bus powered as well if self-power is removed).
I could see a Jetson plugged in without a surge protector as being at risk…but the ESD over the USB port makes me think it would be more likely for a surge to destroy the Jetson and leave the USB device working. If that device is self-powered, and if that power source is not surge protected, then odds go up quite a bit that this could damage the camera. Is the camera self-powered or bus-powered? Is a HUB involved, and is the HUB self-powered or bus-powered?
The camera need a USB3 port to work properly, and it uses the port also as power source.
So the zed is attached directly on the board without any HUB trought the Jetson USB3 port.
Unless there was a power surge which destroyed the ESD protection and overcurrent protection of the USB port the odds of the Jetson causing the problem are very low. Running the Jetson without a surge suppressor could over time lead to failure (you can’t really test ESD components, nor use them, without them degrading…eventually a large number of surges could conceivably propagate through the hardware…but the odds are low that the USB device would fail first).
Long ago I worked as a certified inspector at a small electronics manufacturing company, mostly designing just-in-time through-hole lines. There was properly a bit of paranoia over protection from static. Components which are not in a circuit can be destroyed rather easily…a single discharge could destroy a shelf with around $10k worth of parts. Components in a circuit are far more resilient, but still susceptible to larger jolts.
There was a strong awareness of what type of material any part was allowed to sit on. Some of the more dangerous materials to sit a part on were very good insulators…the issue was in fact about electrostatic potential for non-conductive surfaces/table tops, and grounding for conductive surfaces/table tops. For example, paper on a desktop was banned. Various plastics used on a desktop also have a high electrostatic potential similar to what you might expect when walking across carpet. The only thing I can think of as the highest risk in your use case would be if a desktop were not anti-static, when additionally the material is some form of plastic or paper.
As is, the risk of failure for you would be greatest when the USB cable is not connected and is sitting freely on the wrong material. Still, this isn’t very likely if common USB components are used in the camera itself (USB bridges tend to have built in ESD protection…this is likely at both the camera end of the cable and the Jetson too…both would have to fail if the jolt comes from the Jetson, only one would need to fail if the jolt came while the cable was disconnected).
If there is a relation to your Jetson, then chances are somewhat high that the Jetson’s USB port was damaged. Do you see any sign of overheating near the connector? The same current which overheated the camera would have passed through the Jetson. If you see this, then you know the Jetson was connected to the failed camera, though you still don’t know if the surge producing the failure was from the Jetson.
You can measure the 5V on the connector. Wikipedia has a USB section with some pictures of connectors:
[url]https://en.wikipedia.org/wiki/USB_3.0[/url]
The “Standard-A Plug” would be correct for the full-sized USB3 connetor on the carrier board. A table next to the picture lists the ground for return and the power pin numbers. See what voltage the Jetson actually provides…is it 5V? If so then the Jetson is still functioning as designed (but as mentioned ESD components fail slightly and lose their protection a bit every time a surge is hit and you won’t be able to test that part of the USB connector).