There has been a huge amount of interest when I demonstrated speech recognition working on the Raspberry Pi. However, I would like to announce today that I am discontinuing my work with HMM-based speech recognition. However that does not mean I will stop my activities with speech recognition entirely.

Today I just got back from the Ingenious Engineering Fair, and I must say I'm overwhelmed by the interest in my projects. Thanks! The Robotic Arm with the PS3 controller proved more popular than expected, so much so that by the time I even thought about demonstrating the Dark Pi rover, my laptop's batteries were flat with no chargers in sight. Many of the kids already played PS3 at home, so they were very comfortable with the interface.

Did you think that the Raspberry Pi will only be limited to benign uses? Did you think that the Raspberry Pi will always bask in the light? Well this Raspberry Pi...has embraced the darkness.

I've finally received my Raspberry Pi, and I've immediately gotten to work transferring the speech recognition system I used for the robotic arm to the pi. Due to its small size and low power requirements, the Raspberry Pi is an excellent platform for the Julius open-source speech recognition system. This opens up almost limitless possibilities for voice command applications.

EDIT: I am no longer working on Julius/HTK for speech recognition. Please see this post for more information.

OpenTLD is an open-source visual tracking algorithm by Zdenek Kalal. He released it earlier this year as open-source, and there have been efforts to port the algorithm from the original MATLAB to a C/C++ only implementation.

I haven't been using the Robotic Arm that much lately due to the hassle of getting and installing new batteries. However, since I'm going to make a presentation about the robotic arm tomorrow, I've modified it to take most of its power through a wall socket DC adapter.

Update: demo video now up!

Here is the tutorial in using the PS3 sixaxis controller with the OWI/Maplin robotic arm. It's less impressive than the voice control, however it's still useful in some ways as the sixaxis controller is an excellent controller.

On Friday I managed to enable my PS3 sixaxis controller to work with the robot arm! It's not as impressive as the voice control, but the code might come useful to me someday. The PS3 controller uses bluetooth and acts like a joystick HID device, and I used pygame to help me process the input events.

Additionally, using this I can actually move several joints at the same time. I'll be posting a short tutorial, code and a demo video as well soon!

Here is part 3 for the robot arm with voice control tutorial. Click here for the first part or here for the second part.

Now that the output has been filtered and tested for confidence, the sentence can now be processed to move the arm:

Here is part 2 of the robotic arm tutorial. Click here for the first part.

Running julius

If you've managed to perform Part 1 of the tutorial successfully, then in the command line in the 'voxforge/auto' directory, run:

Julius should then wait for microphone input, and if you speak into the microphone, for example 'elbow up' then it should print output similar to the following: