3/4/13

Voice Controlling Hexy

(This post is a bit rough, but I figured I should get it out there, since I won't be working on Hexy for a little while.)
Before we get started:
  1. The code used to make this all work is on Github. I'm new to ROS, so I don't claim that it's set up correctly.
  2. To get things to ROSLaunch nicely, I had to make some pretty hacky changes to how PoMoCo deals with directories. Basically, it now has to use full paths to every directory ( these paths are created at runtime using __file__ ). I haven't seen it fail yet, and I can't think of a specific failure mode, but it makes me very uncomfortable, and I'm looking for a way to change it.
  3. ROSPoMoCo isn't a full substitute for PoMoCo yet. Offsets, for instance, can't be set in ROS, though they are loaded from the .cfg file.

After a bit of hacking, I've ported most of PoMoCo over to run as a ROS Node. This node listens for new moves on the /moves topic and runs them if it is able to (If it can't find the move, it issues a Warning and ignores it).

At this point, it's time to take advantage of ROS to do neat stuff with Hexy. At first, I wasn't sure what exactly I wanted to do, but some Googling brought up this blog post, in which an iRobot create is controlled by voice. The package used to do this is perfect for controlling something like Hexy -- pocketsphinx will broadcast any recognized phrase on the \output topic, and the set of recognized phrases can be set with a text file.

3/2/13

Starting out with ROS

This is going to be a pretty short post with the purpose of motivating future posts on related subjects.

I've got a lot of really cool robotics equipment now; a stock Hexy, a Cyclone Quadrotor, a Kinect, and a MakerBot Thing-O-Matic top the list, at the moment.

Unfortunately, a lot of these pieces of Hardware come with relatively  little software behind them. Hexy, for instance, has the short-but-sweet PoMoCo software to start. PoMoCo is great, but it's not very functional; by default, it allows only for interpolation between pre-programmed sequences of joint angles. It's very easy to pick the wrong combination of moves and get Hexy stuck in some contorted pose ( and you can forget about variable speed gaits ).

This isn't really PoMoCo's fault. Like Hexy, PoMoCo is designed to be a lightweight tool for beginners who can go on to use the platform for other things.

So, what's next for me on the Software side of Hexy? First off, I want to integrate Hexy with ROS (more on ROS in a later post). At first, I'm just going to hook PoMoCo into ROS and control it from the command line, but I plan on splitting PoMoCo into three ROS nodes, with the eventual goal of augmenting one of them with good gait generation and motor planning, and replacing the other with a series of ROS services to utilize Hexy from any ROS interfaced program.

In any case, I'll be working on Hexy when I  don't have to tool, and tooling when I can to get as much work in on Hexy. I'll keep you posted.