You can use TTS speach output by using the cob_script_server.

Starting Sound

NOTE: If you login remotely via ssh, login without -X.

roslaunch cob_sound sound.launch


You can either call and action or a service, e.g.

rosservice call /sound/say "Hello, my name is Care-O-bot."

You can mute and unmute the output

rosservice call /sound/mute
rosservice call /sound/unmute

Using festival

By default festival is used.

Using cepstral

For cepstral you need to buy a license key.

For using cepstral instead of festival please set the mode to cepstral with

rosparam set /sound/mode cepstral

Installing cepstral vices and license

Download and install voice. Adopted from this tutorial.

  • e.g. Linux 32bit or 64bit, US English, Diane:

  • e.g. Linux 32bit or 64bit, German, Matthias:

  • e.g. Linux 32bit or 64bit, German, Katrin:

  • unpack and install

tar xzvf Cepstral_David_x86-64-linux_6.2.3.873.tar.gz
cd Cepstral_David_x86-64-linux_6.2.3.873
sudo ./
sudo touch /etc/
sudo sh -c 'echo "/opt/swift/lib" > /etc/'
sudo ldconfig

* apply fix for Ubuntu > 12.04

roscd cob_sound
sudo ./

if that fix doesn't help, try to install alsa-oss

sudo apt-get install alsa-oss

and modify /usr/local/bin/swift_fix to contain

if test -x /usr/bin/padsp ; then  exec aoss /opt/swift/bin/swift "$@" ; else  exec /opt/swift/bin/swift "$@" ; fi

* Register voice with license (you need to buy a license from, for IPA robots ask UHR or FMW for license key)

sudo swift --reg-voice

Setting the sound volume

Either use alsamixer:


or use alsactl: For setting the sound to xx% use

amixer -c 1 set Speaker xx%


amixer -c 1 set PCM xx%

5% is a reasonable volume. To store the settings permanently, type

sudo alsactl store

Wiki: cob_sound (last edited 2018-05-29 17:17:46 by FlorianWeisshardt)