Sluggish WiFi connection or even disconnecting

[laserdance]

Hi, thank you very much for your awesome product! Finally I've got through all obstacles and successfully built this awesome robot, but I have big problem: Wi-Fi connection is sluggish, robots reaction is delayed about 10s, as well as refreshing webcam stream. I'm getting 1 FPS per 5-10sec, sometimes it disconnect, etc..

Robot is uncontrollable this way.. But when I try e.g. change default values of servos (on /config.html page), it reacts immediately.

I'm adding log from /log.html:

DEBUG:tornado.general:sockjs.tornado will use json module
INFO:root:Starting web server...
WARNING:root:Got message with invalid checksum
WARNING:root:Got message with invalid checksum
INFO:root:Read 0XACED 0.38
INFO:root:Expected 0XACED 0.38
INFO:tornado.access:200 GET / (192.168.42.14) 67.12ms
INFO:tornado.access:304 GET /css/style.css (192.168.42.14) 86.91ms
INFO:tornado.access:304 GET /css/modal.css (192.168.42.14) 11.75ms
INFO:tornado.access:304 GET /js/jquery.js (192.168.42.14) 33.20ms
INFO:tornado.access:304 GET /js/jquery.joystick.js (192.168.42.14) 11.87ms
INFO:tornado.access:304 GET /js/sockjs-0.3.min.js (192.168.42.14) 13.94ms
INFO:tornado.access:304 GET /images/ajax-loader.gif (192.168.42.14) 15.10ms
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 8.50ms
INFO:tornado.access:200 GET /logs.html (192.168.42.14) 16.28ms
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 8.35ms
INFO:root:SockJS connection closed
INFO:tornado.access:304 GET /config.html (192.168.42.14) 11.26ms
INFO:tornado.access:304 GET /css/config.css (192.168.42.14) 28.62ms
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 6.91ms
INFO:root:SockJS connection closed
INFO:root:SockJS connection closed
INFO:tornado.access:200 GET / (192.168.42.14) 9.79ms
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 5.72ms
INFO:root:SockJS connection closed
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 7.42ms
INFO:root:SockJS connection closed
INFO:tornado.access:304 GET / (192.168.42.14) 9.18ms
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 7.02ms
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 6.75ms
INFO:root:SockJS connection closed
INFO:tornado.access:304 GET /logs.html (192.168.42.14) 13.20ms
INFO:tornado.access:304 GET /js/jquery.js (192.168.42.14) 8.60ms
INFO:tornado.access:304 GET /js/sockjs-0.3.min.js (192.168.42.14) 10.74ms
INFO:tornado.access:200 GET /robot_control/info (192.168.42.14) 6.99ms

Can you please help me? Thank you!!

[Alan]

Hi there,

Welcome to the forums.

What operating system and browser are you using? Other users have reported that newer versions of the Safari browser on Macs has slow video streaming, but that using Chrome or Firefox gives better performance.

If that doesn't help you, then can you tell me how you're powering the robot please?

Regards

Alan

[laserdance]

Hi Alan,
thank you very much for your reply!

No, I tried a lot of devices - Nexus 5, Xperia tablet (on both I tried Firefox and Chrome) and also Firefox on MacBook.

It seems that it should be an issue of robot itself - e.g. red light of camera is lighting after a few seconds it disconnects, then after approx. 1 minute is streaming restored again..

I'm using powerbank, fully charged..

[laserdance]

And I have updated firmware and system to newest version..

[Alan]

Hi there,

This is a bit weird. Your logs look good and it sounds as if everything should be ok.

Some things to look at/try I can think of

• Can you please confirm that the power switch to the mini driver is set to on?
• Are you able to temporarily power your Pi from the wall using a power adapter to see if that helps?
• What WiFi dongle are you using? Is it an Edimax EW 7811Un?
• Can you please check the Pi Camera connection?
• What type of Pi are you using? Model B+ or the new Pi 2?
• Could you please leave the powerbank to charge overnight? Sometimes the LEDs on the powerbank aren't the most accurate indication of charge.
• Has the SD card software been modified in any way? i.e. Have you run sudo apt-get upgrade? If so, could you please try using an unmodified SD card?

Apologies, if the list includes things you've already tried, I just want to make sure I've covered all bases. The main things I can think of at the moment are that the powerbank may be faulty, or that some software has changed somehow, but I can't see any obvious reason for the problems you're experiencing.

Regards

Alan

[laserdance]

Well, I tried all of your suggestions, I tried to upgrade firmware, change Wi-Fi drivers, etc.. Nothing helped.

BUT when I connected robot to ethernet, everything worked like a charm. So I decided to buy another Wi-Fi Adapter. Instead of small Edimax I bought something with bigger antenna (Tenda W311u).

So problem was really obvious - weak Wi-Fi signal for some reason.. Thanks anyway for feedback!