Update, July 2017 – if you really want to try it, much more complete and up-to-date instructions are on github (more).
Here’s how to make a presence robot with Chromium 51, WebRTC, Raspberry Pi 3 and EasyRTC. It’s actually very easy, especially now that Chromium 51 comes with Raspian Jessie, although it’s taken me a long time to find the exact incantation.
If you’re going to use it for real, I’d suggest using the Jabra 410 speaker / mic. I find that audio is always the most important part of a presence robot, and the Jabra provides excellent sound for a meeting of 5 – 8 people and will work for meetings with larger groups too. I’ve had the most reliable results using a separate power supply for the Jabra, via a powered hub. The whole thing still occasionally fails, so this is a work in progress. You’ll need someone at the other end to plug it in for you.
I’ve had fair success with a “portal” type setup with the Raspberry Pi touchscreen, but it’s hard to combine the Jabra and the screen in a useful box.
As you can see, the current container needs work:
Next things for me will be some sort of expressivity and / or movement. Tristan suggests emoji. Tim suggests pipecleaner arms. Henry’s interested more generally in emotion expressed via movement. I want to be able to rotate. All can be done via the WebRTC data channel I think.
You will need
- Raspberry Pi 3 + SD card + 2.5A power supply
- Jabra Mic
- Powered USB hub (I like this one)
- A pi camera – I’ve only tested it with a V1
- A screen (e.g. this TFT)
- A server, e.g a Linode, running Ubuntu 16 LTS. I’ve had trouble with AWS for some reason, possibly a ports issue.
Instructions
Set up the Pi
(don’t use jessie-lite, use jessie)
diskutil list diskutil unmountDisk /dev/diskN sudo dd bs=1m if=~/Downloads/2016-09-23-raspbian-jessie.img of=/dev/rdiskN
Log in.
sudo raspi-config
expand file system, enable camera (and spi if using a TFT) and boot to desktop, logged in
Update everything
sudo apt-get update && sudo apt-get upgrade
Set up wifi
sudo pico /etc/wpa_supplicant/wpa_supplicant.conf
network={
ssid="foo"
psk="bar"
}
Add drivers
sudo pico /etc/modules
i2c-dev snd-bcm2835 bcm2835-v4l2
Add V4l2 video drivers (for Chromium to pick up the camera): argh
sudo nano /etc/modprobe.d/bcm2835-v4l2.conf
options bcm2835-v4l2 gst_v4l2src_is_broken=1
Argh: USB audio
sudo pico /boot/config.txt #dtparam=audio=on ## comment this out
sudo pico /lib/modprobe.d/aliases.conf
#options snd-usb-audio index=-2 # comment this out
sudo pico ~.asoundrc
defaults.pcm.card 1; defaults.ctl.card 0;
Add mini tft screen (see http://www.spotpear.com/learn/EN/raspberry-pi/Raspberry-Pi-LCD/Drive-the-LCD.html )
curl -O http://www.spotpear.com/download/diver24-5/LCD-show-160811.tar.gz tar -zxvf LCD-show-160811.tar.gz cd LCD-show/ sudo ./LCD35-show
Rename the bot
sudo pico /etc/hostname sudo pico /etc/hosts
You may need to enable camera again via sudo raspi-config
Add autostart
pico ~/.config/lxsession/LXDE-pi/autostart
@lxpanel --profile LXDE-pi @pcmanfm --desktop --profile LXDE-pi @xscreensaver -no-splash @xset s off @xset -dpms @xset s noblank #@v4l2-ctl --set-ctrl=rotate=270 # if you need to rotate the camera picture @/bin/bash /home/pi/start_chromium.sh
pico start_chromium.sh
#!/bin/bash myrandom=$RANDOM #@rm -rf /home/pi/.config/chromium/ /usr/bin/chromium-browser --kiosk --disable-infobars --disable-session-crashed-bubble --no-first-run https://your-server:8443/bot.html#$myrandom &
Assemble everything:
- Connect the USB hub to the Raspberry Pi
- Connect the Jabra to the USB hub
- Attach the camera and TFT screen
On the server
Add keys for login
mkdir ~/.ssh chmod 700 ~/.ssh pico ~/.ssh/authorized_keys chmod 600 ~/.ssh/authorized_keys
Install and configure Apache (I used this guide for letsencrypt)
sudo apt-get install apache2 sudo mkdir -p /var/www/your-server/public_html sudo chown -R $USER:$USER /var/www/your-server/public_html sudo chmod -R 755 /var/www nano /var/www/your-server/public_html/index.html sudo cp /etc/apache2/sites-available/000-default.conf /etc/apache2/sites-available/your-server.conf sudo nano /etc/apache2/sites-available/your-server.conf
<VirtualHost *:80>
ServerAdmin webmaster@localhost
ServerName your-server
ServerAlias your-server
ErrorLog ${APACHE_LOG_DIR}/your-server_error.log
CustomLog ${APACHE_LOG_DIR}/your-server_access.log combined
RewriteEngine on
RewriteCond %{SERVER_NAME} = your-server
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,QSA,R=permanent]
</VirtualHost>
sudo a2ensite your-server.conf sudo service apache2 reload sudo service apache2 restart
Add certs
You can’t skip this part – Chrome and Chromium won’t work without https
sudo apt-get install git sudo git clone https://github.com/letsencrypt/letsencrypt /opt/letsencrypt cd /opt/letsencrypt ./letsencrypt-auto --apache -d your-server /opt/letsencrypt/letsencrypt-auto renew >> /var/log/le-renew.log sudo /opt/letsencrypt/letsencrypt-auto renew >> /var/log/le-renew.log sudo mkdir /var/log/ sudo mkdir /var/log/lets-encrypt
Auto-renew certs
sudo /opt/letsencrypt/letsencrypt-auto renew >> /var/log/lets-encrypt/le-renew.log crontab -e
# m h dom mon dow command 30 2 * * 1 /opt/letsencrypt/letsencrypt-auto renew >> /var/log/lets-encrypt/le-renew.log
Get and install the EasyRTC code
Install node
curl -sL https://deb.nodesource.com/setup | sudo bash - sudo apt-get install -y nodejs
Install the easyrtc api
cd /var/www/your-server/ git clone https://github.com/priologic/easyrtc
Replace the server part with my version
cd server rm -r * git clone https://github.com/libbymiller/libbybot.git cd .. sudo npm install
Run the node server
nohup node server.js &
Finally
Boot up the pi, and on your other machine go to
https://your-server:8443/remote.html
in Chrome.
When the Pi boots up it should go into full screen Chromium at https://your-server:8443/bot.html – there should be a prompt to accept the audio and video on the pi – you need to accept that once and then it’ll work.
Troubleshooting
Camera light doesn’t go on
Re-enable the camera using
sudo raspi-config
No video
WebRTC needs a lot of ports open. With this config we’re just using some default STUN and TURN ports. On most wifi networks it should work, but on some restricted or corporate networks you may have trouble. I’ve not tried running my own TURN servers, which in theory would help with this.
No audio
I find linux audio incredibly confusing. The config above is based around this answer. YMMV especially if you have other devices attached.
PlanB 