this is my last week at the lab. It has been a great summer and I have a lot of fun this summer and have learned a lot more. I was able to figure out what i want to pursue a career in and even better how I an going to do it. I want to thank everyone who had a part in me being here I really appreciate it
]]>A couple weeks ago we installed ROS 0.5 on an ASUS eeePC. For the most part the installation ran very smoothly.
The only hiccup in the installation that we had was a problem with apt-get, which was resolved by running the following command:
sudo apt-get update
After this, ROS installed for us without any errors.
Since we first installed ROS 0.5 a couple weeks ago on the laptops, there has already been several updates to ROS. ROS 0.6 was released last Friday. The installation process for ROS 0.6 is now (pretty much) fully automated and has been simplified down to three steps:
Step 1: pre-install
The pre-install just makes sure you have everything you need to run the “ROS grand-unified-installer", and varies slightly depending on the operating system.
Step 2: install
ROS now uses a rosconfig tool to automatically install a ROS configuration on your machine. The steps are os-nuetral:
wget http://ros.sf.net/rosconfig -O ~/rosconfig
chmod 755 ~/rosconfig
~/rosconfig bootstrap http://ros.sf.net/config/stable.rosconfig ~/ros move_base_stage
P.S. It will take about two hours or so to install, but at least its a hands-free installation!
Step 3: enjoy
Basically, the installation is done now, but to make things more convenient, you can set the ROS environment variables automatically whenever you open a new shell:
~/rosconfig setup ~/ros > ~/.bashrc.ros
echo "source ~/.bashrc.ros" >> ~/.bashrc
2. Troubleshooting
When we first tried running a network of ROS nodes on more than one computer, it appeared that the eeePC would only receive messages, and was not sending out any messages.
After hours of frustration and searching through message boards, we finally learned what
the problem was. ROS requires that all machines involved in the network be able to ping each other by host name.
The easiest way to do this on Ubuntu is by using Zeroconf, which is analogous to Apple’s Bonjour technology. Zeroconf should already be installed and configured if you are using Ubuntu 9.04.
If you are unsure whether or not Zeroconf is installed and working, you can test it by pinging your machine from another computer like this:
ping hostname.local
Make sure you include .local suffix after the hostname. If it works, then Zeroconf is already setup and running.
After you confirm that Zeroconf is setup properly, the only thing you need to do is tell ROS that you want to use hostname.local instead of hostname to identify your machine. You can do this by setting up the following environment variable in your .bashrc file:
export ROS_HOSTNAME=hostname.local
Once you do this on all the machines that could not be pinged by name, ROS should work fine.
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