Carlitos’ Contraptions

Kubuntu Karmic Koala

Kubuntu Karmic Koala is finally out! I use it since the Release Candidate came  Oct. 22 nd, and it is absolutely awesomely mind-blowingly fabulous.  All of the kinks in Jaunty have been fixed and a lot of new features have been added.

Kubuntu?

Why am I talking about Kubuntu and not about its more popular sibling Ubuntu? Well, very simply because KDE kicks Gnome’s ass any day (while blindfolded and with all of its finger stuck in its nose). I know that seems like a very bold and unjustified statement, well it is indeed very bold but totally justified.

The main difference about KDE and Gnome, besides the fact that the KDE foundation is much more solid, flexible and portable, is the mindset. In KDE you can configure (trough a nice GUI) pretty much everything, whereas in Gnome, you get a bunch of very comfortable defaults that (although they can be modified) are not intended to be fiddled with too much.

Also, KDE is much more than a desktop environment and provides a full suite of programs that do almost everything you could want to do. These programs also integrate very well together and provide as many more features and options than any sane person would need or be able to use (but who likes sane people anyway?).

Quick Review

My Desktops (Grid View)

I am currently using the 64-bit version of Kubuntu and it is performing incredibly well. The system (my laptop) boots in around 40 seconds and turns off in less than 15 seconds. The graphical performance is flawless and I can benefit from smooth performance even when doing very processor intensive tasks (such as stitching photos together).

Also, It comes with Ubutu One (a remote storage service) which is pretty convenient for sharing and backing up files.

I’ll try to do a screencast and post it in order to show off the Koala.

Lately, I have been working on a very cool project: The Axion, an automated paint mixing machine.

I was very lucky to work with Panaxion, a start-up company based here in Montreal, on the manufacturing-prototype of their invention, the Axion. It consists of an automated on-the-fly paint-blender and paint-applicator.

The Axion?

The Axion is a paint mixing device composed of five paint containers, a paint flow control system and a paint blending apparatus. The whole system is controlled by a PC. As you select a colour from a user-defined colour palette in the Coloraxion software, the machine dispenses the appropriate amounts of different colour paints in order to produce the desired blend.

The machine is rather ingenious and is going to make its debut in the professional decorative painting realm very soon (I’ll keep you posted on that).

My Involvement

I was involved in the mechanical and electrical design of the first manufacturing prototype. I was lucky enough to learn SolidWorks and draw the entire machine (up to the very last detail). The resulting 3D model was then used to build the actual prototype and to produce some multimedia material. Needless to say that I was very happy to participate in the construction.

Title:	The Axion
Description:	Concept video based on the SolidWorks CAD model.

Did you say start-up?

Panaxion is a start-up company and is soon going to manufacture Axions. Their website is under heavy construction at the moment but it should become stable (and beautiful) soon. If you are interested in decorative painting (in the non effeminate sense), I suggest you keep an eye on this project.

I used the automated panoramic photography rig (or Panoramaker, for short) in order to make some panoramas here in Montreal.

After having the rig working, I went out on my bike with my tripod, my laptop, my digital camera and the panoramic photography ri. I decided I wanted to capture the sunset at Mount Royal but when I was halfway there, I noticed that the sun became completely covered by clouds.  So I decided to shoot some other panoramas instead.

CCA

Here is a nice 360 deg view of the Maison Van-Horne Shaughnessi (a.k.a. The Canadian Centre for Architecture). This building is located here. Keep in mind that you can click on the title in order to see the panorama full-screen.

Title:	Maison Van-Horne Shaughnessi
Description:	A 360 deg panorama shot from the sidewalk.

When watching carefully, it is possible to notice a little parallax error near the base of the descriptive plate in front of the building. I could have corrected this but I noticed it too late and I am extremely lazy. You can also see some cars blending with their surroundings as Hugin, the panorama stitching program, tries to make sense of a changing scene (with cars passing by).

Place Ville-Marie

This is a panorama of Place Ville-Marie taken at the central fountain.

Title:	Place Ville-Marie
Description:	A 360 deg panorama shot at the Place Ville-Marie fountain.

The parallax errors in this one are much more significant, but then again, laziness got the best of me. They are mainly caused by the fact that the camera was not perfectly flat on the tripod when shooting this.

If you want to know what are the tools used to create these panoramas, please read my previous posting on Making Panoramas.

As promised before, here is the Python script that runs my panoramic camera hardware. It is a very quick prototype and is by no means intended for widespread use since it requires manual calibration. Nevertheless, it might be very useful to those seeking to learn how to position the servos or control a digital camera through Python.

This script requires my Pololu library and includes some codes from here in order to control the camera. Besides the basic requirements of lib_pololu,  the script also requires gPhoto. If you are running Linux, you most likely  already have it but in case you do not, you can install it through your favourite package manager or by using the console (e.g. for Ubuntu/Debian):

sudo apt-get install gphoto

If you are using some other OS, you can download gPhoto from here.

The Code

Again, many thanks to RobotShop who provided the hardware that made this project possible.

Update:

Read the follow up posts: Panoramaker, where I expose the software, and Automatic Panoramas in Montreal, where the final result can be seen.

I have finally completed my second project sponsored by RobotShop. I apologize for the immense delay, I really missed my promise of rolling out a new project every two weeks. Let’s just say that I had a lot going on lately and I could barely keep up with my obligations, let alone blogging or building new projects.

Place Ville-Marie Panorama

This time, I built a panoramic camera. My main objective was to have a platform that can be used with pretty much any camera and that can produce panoramas with a minimum of work. If there is enough interest from the public and if this prototype is well received by the DIY community, I’m planning to produce (and hopefully sell) kits that would include all the parts to build this device.

Materials

• Hitec HS-785HB Winch Servo Motor
• ServoCity SPT200 Direct Drive Pan & Tilt System
• Pololu Micro Serial 8 Servo Controller
• Hitec HS-425BB Servo Motor
• A digital camera
• Small plastic container
• Battery holders
• (Rechargeable) Batteries
• A piece of aluminum (I used an old heat sink)
• A long nut (of the same size as a tripod screw)
• A screw (that fits into the tripod attachment on the camera)
• A tripod
• Cable ties
• A small piece of neoprene (or any other mushy substance)
• A USB to Serial cable
• Some female headers and wires

Putting It Together

Panoramic Camera Mount

The first step was to put together the ServoCity Pan and Tilt system. This took away much of the building work since it is really simple to put together in no time at all. Nevertheless, I applied some modifications to it: I discarded the bottom plate that should be attached to the panning servo (since I am using a larger winch servo that would not fit otherwise), and I drilled a hole on the top plate in order to be able to fasten the camera to the rig. Note that I also included a little piece of neoprene that was lying around in order to prevent the bottom of my camera from getting scratched.

The mounting hole for the camera must be placed so that the lens’ pupil is at the centre of rotation. This way, the horizontal rotation axis will be close to the no-parallax-error point  (or whatever it is called) of the camera and will minimize the parallax errors.

Then, I used an old heat sink as the main structure since it is sturdy and basically free. I used the trusty Dremel to adapt it and cut the proper holes and slots in order to mount all the remaining pieces. The pieces to be mounted on the aluminum plate are the battery holders, the Pololu servo controller, and the winch servo motor. (or whatever it is called

I encapsulated the Pololu servo controller in a small plastic container I got from for free while on a trip with my girlfriend to the beauty/ soap/cream shop. I also used two 2-AA battery holders in order to provide power for the servo motors. I used 29000 mAh NiMH rechargeable batteries that gave me several hours of autonomy. In order to connect the battery holders to the controller, I soldered a two-position female header and insulated the leads with heat-shrink tubing.

I used almost exclusively cable ties to tie everything on the aluminum plate except for the winch servo motor that I screwed in and the long nut that was also screwed in place (after being drilled sideways).  I also had to drill the bottom aluminum face in order to allow for the tripod screw to be inserted into the nut.

Operating it

Panoramic camera in action

This first prototype requires a laptop to be operated, which can be a little annoying.  I plan to use my EeePC in the immediate future and an embedded computer for an eventual commercial kit. It basically works as follows:

1. The camera is set on the panoramic mount, which is fastened to the tripod.
2. The servo controller and the camera are connected to the computer trough their respective USB cables.
3. The controlling program is run.
4. The user waits in awe while the camera takes pictures by itself.

In order to control the hardware, I use a python script that uses my Pololu library and gPhoto in order to operate the servos and the camera respectively. I chose gPhoto since it supports a very wide range of cameras and it is very easy to use.

For now, taking a full 360 panorama takes about 15 minutes. This is a very long time and is mostly due to the fact that my script was hastily put together without care about the performance and in very little time. I will, very soon, post a cleaner version of the code, as well as all the panoramas I took properly processes and in full format, similarly to what I did with my San Francisco panoramas.

Acknowledgements

RobotShop.com

I would like to thank the great people at RobotShop for providing the Pololu Micro Serial Servo Controller, the  ServoCity SPT200 Direct Drive Pan & Tilt System, and the Hitec HS-785HB Winch Servo Motor. This is the second (and hopefully not the last) project they sponsor here at Carlitos’ Contraptions. Without their help, I would have never been able to afford any of the materials (except for those that come straight from the garbage as usual).

They have also being very patient and understanding about my unexpected delay in rolling out this project.