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Why is my IoTiny wifi dropping connection when the Camera is started?
Related Hardware EZ-B IoTiny
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I am fortunate enough to have enough spare parts to be able to just swap out components until the problems go away. I have a box of servos, cameras, EZB etc labeled suspect that I will eventually get around to looking at (or maybe not).
If you have an intermittent faulty device it can also be load or heat related. Example Camera or EZB gets hot (dry solder joint or faulty component). When I was a young field tech I used to keep a hair dryer and a can of spray freeze in my tool kit so I could heat up circuits and spray freeze components to try and find the faulty one.
Fault finding sometimes doesn’t even resolve by swapping out components. Sometimes it is external. Example wifi issues can occur when someone turns microwave or other electronic device on.
Troubleshooting is a science. You can quote me on that. LOL.
I have tried everything listed above to answer DJ question the camera stops working first then 60% of time the connection Wi-Fi drops after that.
I have top quality network hardware with more than enough bandwidth the router this is connecting to is 5 feet away from it. I am having this issue no matter what the power source is my UBEC’s or bench power supply I am having the issue connected to the IOTiny or any of the other two EZB4’s with nothing else connected to them. I have tested the cable that came with it and re crimped each connector. I also made a new cable and tried that and had the same results. Sometimes it seems to work ok for a bit and then stops.
The only thing that I have not changed out is the camera itself.
But I need clarity on this statement you made. I want to see if you accidentally meant something different.
It sounds like everything that you are using (IOTiny and EZB) are behaving the same way. Is that what you meant?
My question is can't this connection issue be self corrected in the ARC application without having to shut the ezb4 down and restarting it to get the camera back online? I just think this code can be made to have more resiliency.
Also note there is nothing else connected to this EZB4 currently and I have also tested this in AP and client mode with the same outcomes.
May I ask what you are using as a power supply?
if it is connected to the IOTiny it is closer to more wires and also disconnects faster than when it is connected to the ezb4
I have to tell you this is crazy that this stuff is so touchy. Same thing with the MPU6050 it will also lock the ezb4 up sometimes forcing a restart. When you have a few thousand dollars in your robot the last thing you want it to do is lockup and need to be restarted all the time. I really want to love this hardware platform but I have to tell you it has proven to be a challenge. I am not sure if it a hardware design issue or a software issue.
If you think about this is just like a webcam and it should not be so touchy.
My first camera which I never used before this project was ordered over a year ago along with the IOTiny I had at the start of this post would also cause the Wi-Fi to disconnect when it failed like 30-40% of the time with the new camera that no longer happens to the Wi-Fi it just stops for no reason.
before this post I had everything powered and it was working for just over an hour and then stopped working in ARC
Here are a few hardware areas that I see that are different:
1. You are using a CCTV 2.1mm barrel plug power connector. Internally these plugs have 22 gauge wire that connects the terminal blocks to the barrel, in high-current-demand situations these small wires to heat up, increase in resistance, and cause brownouts. I would recommend a different barrel plug for higher currents or open it up and solder thicker gauge wires from the terminals to the barrel.
2. You are using 3rd party servos, as I can see by the red-orange-brown wires. We have no idea what kind of noise-related issues servos from other manufacturers can cause. We have tried our best to make the highest quality product possible but if the servos are very low quality it is very difficult to mitigate such a thing. When you are developing a completely DIY solution with parts and pieces from many different suppliers they may not jive together perfectly. You are likely running into the same sort of challenges that we had in developing our product from the ground up. Not everything works together perfectly the first time, you need the right tools and knowledge to diagnose the challenges you are facing.
3. I still am unaware of what you are using as a power supply. Are you using a LiPo battery or wall power? Wall power is difficult to use with servos, as the inrush current can cause brownouts (which can lead to disconnects). The supply usually needs to be rated for a current rating 3-5 times the demand you think you'll need. For example for a display JD that we sent to Brookstone stores for a demo, it had 10 servos, we only expected to have peak current use of ~5 Amps and in the end, a 5V 20Amp wall power supply met our needs.
I have more to discuss and clarify, but I'll leave it at this for now.
As you can see by the below picture it is connected to a bench power supply set to deliver up to 10amps if needed and currently with the only three servos connected to the IOTiny in a holding position everything is only drawing .339amps.
The black board next to the EZB4’s on the right is just a servo power breakout board to power some other servos at 11.2v and the buck converter next to that is getting 8.4v on it’s input and providing 5.2 on it’s output but is not have anything attached to it.
It should also be noted the audio is connected only to the IOTiny there no audio connected to the EZB4’s
The other thing to note is that in this office I have a lot of computer equipment that all uses Wi-Fi and Bluetooth. This does seem to be an issue for any other equipment, and yes I have checked the noise level and the channel usage with a scanner should not be an issue. I am also a HAM operator and all my radio equipment is off. My main network router is 6 feet away from the EZB4’s and IOTiny. I also have high speed fiber internet service.
I have a bit of knowledge to share with you about current draw and inrush current. Average current draw is fairly easy to mitigate as it is predictable and steady, you can be fairly confident when you spec out a power supply that you can trust that it can deliver the current you need. This goes out the window with DC gear motors that have a huge starting-up (inrush) current to get them to move their gears. The current demand spikes up to a large level that will take the voltage supply down to the point of a brownout or just low enough to cause issues. Inrush current happens so fast that it's very difficult to measure, a clamp meter is sometimes used for larger motors, but for smaller motors it gets a bit trickier. An oscilloscope can be used to measure it but there are some challenges involved. It seems that I was a bit off with my numbers above, I just found a webpage that says the following "Inrush current can be 4 to 10 times greater than the normal running current". Don't just take my word for it, do some searching and check it out for yourself.
Using a bench-top power supply can cause issues, I know this because I have first-hand experience with it. I have a Chinese 30V/10A power supply on my bench that does not do well with inrush current or with noise. It can't handle too many servos and adds additional noise to the audio circuit which means the power coming out of it is not clean. It works in a pinch but it is problematic at times.
I would recommend testing your setup with a Lead-acid or LiPo battery to see if some of your issues get resolved. If you can eliminate a few other variables it will get you that much closer to a solution. Voltage regulators, UBEC, and Switching power supplies also have issues with inrush current, you may have to question them as well. I also don't have much experience with UBECs so I don't know what to expect from them.
For noisy servos, tank capacitors across the power rails can also help. You could add 100-1000uF electrolytic caps across the power rails directly at the servos to see if that cleans up the power issues as well. As I'm sure that you're aware since you're a HAM operator: Don't reverse the polarity of your caps when connecting to power or they may explode.
I'm not as worried about the WiFi interference as it does take quite a bit of interference to disconnect an EZ-B. Like a trade show's worth
In my experience, most weird electronics issues are 90% power related.