OR-WRT 0.70-Eng

Russian version

About

OR-WRT control panel.

Project description

This is subproject of Open Robotics project, intended to production easy-to-use, low-cost platforms for hobby robotics (also not only hobby). This subproject target is to develop ready-to-flash firmware for SOHO wifi-routers, which allows to use the linux-based routers as a head devices for wifi-controlled hobby robots. Router will be able to control UART- and USB devices (for the moment, UVC-webcams, some MCU boards and some USB-UART adapters are supported). Firmware is based on the OpenWRT, author - elmot (elijah.mot [at] gmail.com).

URL to forum about this project

• [OR-WRT development topic]
• [OR-WRT user support topic]

License

You can freely use and/or modify the project materials for any non-commercial purpose. For commercial license you have to contact author (elijah.mot[at]gmail.com).

WARNING

You are doing all modifications on your own risk. We warn that disassembling the router (to connect uart-interface), as far as flashing custom firmware, may lead to loss of warranties or even to device damage. Unexpected robot behavior could lead to damages or even injures. The author of the firmware, neither Open-robotics.ru, nor OpenWRT.org don't carry any responsibility for any direct or indirect consequences of projects materials usage.

Supported equipment

Routers

• 

  TP-Link MR3020

• 

  TP-Link WR703N

• WiFi routers:
  • TP-LINK MR3020
  • TP-LINK WR703N
  • May be any other routers, based on SoC Atheros AR9331(not tested yet)
  • You can try to modify firmware by you own for other USB-equipped routers compatible with OpenWRT.org

USB-Webcams

All UVC-webcams (consider this list — [http://www.ideasonboard.org/uvc/]).

Video noise is reported with webcams Logitech С-270

We recomment MJPEG-webcams, but YUV-webcams can be used too (but with increased latency of video-streaming).

USB-UART adapters

• Silicon Labs CP210x, including OR-USB-UART-v1
• FTDI
• Prolific PL2302
• Pololu Orangutan SVP-1284 (with some patching, see below)
• Others weren't checked, most likely will be supported..

Firmware installation

TODO

Robot firmware setting up

There are two ways to set-up OR-WRT wirmware

• initial: telnet 192.168.217.1 then passwd and set the main password. You have enter it twice.
• ssh 192.168.217.1, with LAN cable connected to any router LAN/WAN port. Also ssh <wifi ip>, if wifi is already configured and up. Login root, password as was set initially
• Type in in browser http://192.168.217.1 with LAN cable or http://<wifi IP> via wifi, if wifi is already configured and up. Login root, password as was set initially. There is a link to admin pages on the frontpage.

Home WiFi connection

Robot head device(customized router) is supposed to be connected to a home network wifi as the static IP client.

• Select approaching IP. It should be in IP range of the network, not to be occuped, and to be out of DHCP address range.
• Open web interface, then admin pages, and there is a "WiFi" page. There you can set up:
  • protection: WPA-PSK/WPA2-PSK, NONE
  • network SSID
  • password
  • static IP
  • netmask
  • default GW
  • dns

As a network configuration check, firmware pings default gateway address every ten seconds. If the ping is unsuccessful, the blue LED is lit for next ten seconds. So it can light time to time even if wifi is working IP in case of packet drop (it happens time to time).

Webcam Settings

On camera settings page you can choose:

• resolution
• frame rate
• camera number (connection of several cameras through USB-hub is possible)
• YUV or MJPEG modes

Firmware usage

Videostream and singler frames

• Videostream in mjpg format: http://wifi-ip:8080/?action=stream
• Single frame in jpg http://wifi-ip:8080/?action=snapshot

UART

Internal UART

There are two ways to access it

• ser2net daemon redirects UART traffic through TCP port 2000
• you can write to UART with http protocola at URL /cgi-bin/serial.cgi , POST method, Http parameter SERIAL_DATA value will be sent to UART

Silicon Labs CP210x (OR-USB-UART), FTDI, Prolific PL2302

Add the following line to /etc/config/ser2net.conf file:

3001:raw:600:/dev/ttyUSB0:115200 NONE 1STOPBIT 8DATABITS -XONXOFF -LOCAL -RTSCTS

After router reboot serial traffic will be redirected to TCP port 3001

Pololu Orangutan SVP-1284

Thanks to tenik, I was able to connect the router to Pololu Orangutan:

Append following lines to /etc/rc.local to restart UART kernel module:

rmmod usbserial
insmod usbserial vendor=0x1ffb product=0x0087

Append following lines to /etc/config/ser2net.conf:

3001:raw:600:/dev/ttyUSB0:115200 NONE 1STOPBIT 8DATABITS -XONXOFF -LOCAL -RTSCTS
3002:raw:600:/dev/ttyUSB1:115200 NONE 1STOPBIT 8DATABITS -XONXOFF -LOCAL -RTSCTS
3003:raw:600:/dev/ttyUSB2:115200 NONE 1STOPBIT 8DATABITS -XONXOFF -LOCAL -RTSCTS

After router reboot, Pololu's 3 UART ports are accessible on TCP ports 3001, 3002, 3003, respectively.

How to modify firmware

For serious firmware modification see documentation on OpenWRT

Uploading custom web-pages for robot control

Actual webpages is available for download through robot admin "site". For new pages uploading by WiFi I use command:

pscp.exe -r -pw 123 -scp www/* root@192.168.1.120:/www

pscp is utility for SSH upload from Putty distributive.

Don't upload files to /cgi-bin/* this way, uploaded files will have wrong linux attributes and they won't work.

Unsolved problems

• Video latency. In 160*120,30 fps MJPG mode it's minimal, but still exists.
• No easy-to-use password change method, only through SSH console (passwd command).
• Security. Robot with such firmware should be controlled through secure protocol. Now video is streamed unencrypted on 8080 port . Web-face and controls - through http or https, with or wtihout password. Most correct method - https+password but https connection is very slow.
• Webface scripts written on awk & ash, support is difficult, need to be migrated to Lua.
• Webface is undeimplemented - settings pages always shows default values instead of current settings.

Other warnings

• Don't disable both HTTP and HTTPS at the same time. In this case router reconfiguration will be available only through SSH.
• Don't forget about security risks. Remember, that somebody may spy on you through webcam, and mobile robot can damage something or even cause injuries.

Downloads

• Download from SourceForge

What inside?

• Ready-to-use firmware in .trx-format.
• Kernel and addons for standard OpenWRT's ImageBuilder(10.03.01-RC6), used to build the firmware.
• make.sh file, which builds and packs the firmware.

Links

• OpenWRT
• Putty - SSH-client for Windows