Dawn Robotics Forum

HI,

Have tried various Wifi dongles including purchasing the recommended one. I have purchased the SD card with the software installed and built the robot. Upon powering up the camera moves a bit , that's the lot. I can't see the Pi on the network (as I can see everything else) and it seems there is no Wifi. The pi and Wifi dongle works with other cards and allows me to ssh into them but not when loaded with the Dawn software. Also tried two other Pis including a Pi2, no avail.Tried every variation I can think.
Where do I go from here?
I can't access the Pi with the Dawn card in place so I can't do any diagnostics.

All thoughts welcome.

Kevin.

Hi Kevin,

Welcome to the forum.

Sorry to hear you're having problems with your robot kit. Can you tell me how you're powering your robot please? If you're using non-rechargeable batteries (Alkaline) then they probably won't be able to provide enough power to run the robot.

If you have a power adapter so that you can plug your Pi into the wall then this can be a good way to run the Pi whilst debugging.

If you're not able to connect via WiFi then 2 ways to see what's going on are either to connect a network cable and SSH in, or to attach a keyboard and monitor.

Regards

Alan

Hi,

I've tried both power from the wall and from a portable supply. The Wifi dongle appears to work (as it lights up) but cannot be detected unless I use a standard OS on a card. Then I can see it and SSh into it. This suggests a corrupted card. However I will connect it via Ethernet and come back with the results here.

Kevin

Hi Kevin,

We test all of the SD cards in a robot as we flash them, but there's always a slight possibility that for some reason you may have got a corrupt one.

If you could try to SSH in or connect a monitor to see if you've got a corrupt SD card then that would be very helpful. Might also be worth having a look at the card using an SD reader on a PC to see if there's anything obviously wrong.

Regards

Alan

Hi,

Thanks for coming back to me.
I've added a monitor and keyboard and can now see the boot up sequence. The end of which shows a Raspberry Pi graphic with a wastebasket icon and a menu top left, this being the Pi version of the control screen. No other processing seems to be going on. The Wifi dongle appears to be working with a flashing blue light although as before it is not recognised by the network.

First question therefore is should this screen be showing?

What should I do next to progress the situation. Can I do some diagnostics to check the card status. I don't know how to capture the boot output to screen to a file or a printer. Lsusb shows all that should be there including the Edimax wireless adaptor.

Thanks in anticipation. Sorry to be pressuring you, but due to a recent transplant I am somewhat limited at the moment to where I can wander so the robot makes a very good re-introduction to robotics to spend my time along with modelling and my amateur radios. In other words I have a lot of time on my hands! lol.

Cheers,
Kevin

Hi Kevin,

Always happy to provide support. I think that robotics is a good way to spend your time whilst convalescing, although by its nature it can sometimes be a bit frustrating whilst things are going wrong so lets try to speed your path to the fun stuff.

I'm a bit confused when you say that you can't see the Pi on the network? The SD card should be configured to run the Pi as an access point with an SSID of Pi_Mini_Robot. If you look for it with a PC or phone you should be able to see the network and connect using the password 'Raspberry' (note the uppercase R at the start). Once on the network you can connect to the robot using Chrome or Firefox by typing the IP address 192.168.42.1 into the address bar.

It's possible that the WiFi network could be a bit slow to come up at startup, and there can also be problems with power on startup (although this shouldn't be a problem if you're running from a wall adapter). There's a script running on the SD card to try to keep the WiFi alive so this may mean that if the network isn't there when you first start up, it will be a short while later.

If you can't see the Pi_Mini_Robot network, could you please send me the result of running the following?

ifconfig wlan0

Cheers

Alan

Hi,
Sorry If I appear to have not made it clear. I have tested all of the kit individually and it all works. It only does not work when the purchased card is in the Pi. It does not show as existing on any of the standard Network analysis programmes including Famatechs IP Scanner which is one of the progs I am using. This shows all addresses and the devices attached. When a standard OS is in the PI it shows as RASP on 198.168.1.86. With a power off and a reboot with your card it does not show. There lies the first problem.
Power is not an issue. The Pi has been left to 'bring up the Wifi' for various times to no avail so it's not a time issue.
The result of ifconfig wlan0 is as follows:-
Link encap:Ethernet lWaddr 74:da:38:Oo:3f:d4
inet addr:192.168.42.1 Bcast192.168.42.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU 1500 Metric:1
Rx packets: 0 errors:0 dropped:0 overruns:0 frame:0
TX packets: 0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelan:1000
RX bytes:0 (0.0.8) Tx bytes:0 (0.0.8)
(the above copied by hand)
I am OK with using the Pis I have normally and have a broad understanding of the basic such as passwords and access etc, the problem is that I cannot get that far. I was hoping for some test to see if the card is doing what it should be doing. I am surprised that the boot sequence ends with a browser page showing the Pi logo for instance.
I guess it's something simple but for the life of me I cannot see it.
Works fine with another card ( our house alarm system for instance and the robotic arm from Magpi also) but appears to boot OK with your card but then fails Wifi - wise.

Hope this helps and I await your views.
Thanks

Kevin

Hi Kevin,

I'm assuming that with the standard OS SD card in the Pi that the Pi is connected to your home WiFi router, is that correct?

When the Pi uses our SD card, it will not be connected to your WiFi router (although it is possible to reconfigure it later to do this). Instead it will act as a WiFi router itself, with an SSID of Pi_Mini_Robot. Therefore in order to connect to the robot, you need to change the WiFi settings on your PC to disconnect from your home router and instead connect directly to the Pi robot.

Apologies if we're talking at cross purposes, or if I'm misunderstanding. But at the moment it sounds to me as if you're using tools like IP scanners to search for the Pi on your home network? If so I'm afraid that you won't find it, as it's not there, but instead happily running its own network.

By the looks of it, the Pi's networking is running fine as 192.168.42.1 is the address I would expect the robot to have.

I chose to set the robot up as an access point so that in theory it would be easier for people to connect to, as they would be able to connect to it anywhere with just their mobile phone or tablet, and so that they wouldn't need a router.

Regards

Alan

Hi,

Excellent!
We have now moved forward! So simple to have missed it. I can now see the Pi_Mini_Robot network at last (showing limited connection, but I'm not sure if this is relevant).
When running it under Chrome I can see the two 'buttons' and a flashing 'broken image' logo at the top of the page, I assume the picture element not making it. Nothing else.

I shall check all connections, especially power and the camera anyways, but if you have some experience in this area then I'm hoping I can get somewhere, again with your help.

I am also checking the forum for answers.

Thanks again,

Kevin.

Hi,
It's working (well it will do for me now)!

The robot is now responding to the control program, not perhaps all the right direction etc but I am happy to spend my enforced free time to sort that out after all of your excellent help.
Fast, accurate, polite and with patience is the mark of a good support system and I cannot fault any of that. Moving from an electronics background which started when Thunderbirds had strings, your assistance to the 'idiot' on the other end was just what was needed and I'm happy to recommend the experience to anyone.

Thanks very much, I'll try not to bother you again!

Kevin.