[Expelliarose] Some kind of recognition


This evening, we managed with Hugues to make IMU data streaming and DTW recognition work together. We only made really simple tests : try an movement following y axis and one following z axis. They were recognized but there are no management of false positive still. They road is long but we are still pretty happy with the result.

Good night,


[Expelliarose] Laser Tag and DTW

Here it is :

The IR emission and reception have been included in the wand handler thread. Now if receive an attack from any opponent that hasn’t attacker for less than 2 seconds, a led animation will be displayed. We have done some test : even in the wand, the receiver seems to work great, still the range is not that high : a few meters (2-3) but we can still increase the power of the emitter by reducing its resistance. So we have been able to play some laser tag as tests.

However : we are facing some weird bug : if the PCB is not connected via USB to a computer, the thread seems to crash after a few receptions. We will have to handle that problem tomorrow.

Moreover, I’m still continuing to do some test for the DTW algorithm for gesture recognition. The first results seems encouraging and now I’m coding a better program that will handle new series of data faster because we are going to do plenty of tests to see what gestures are best recognized.

See you,


First IR detection

Hello everyone,

I just made my first communication in infrared. I am now able to detect a 38 kHz modulation with my receptor. I also began to implement the RCMM protocol (http://www.sbprojects.com/knowledge/ir/rcmm.php). It seems that everybody wants to have is own IR protocol but they are usually simple and the RCMM seems to be best supported by the receptor. You can see the result of some bits encoded with this protocol as they are received by the receptor.

I now need to implement the demodulation of this signal. Which seems to be the hardest part.


IR reception


Old memories of Solidworks

This is it, Expelliarose’s magic wand is about to be real. We have concieved with Aïmen a simplist prototype to carry the PCB, Leds, IR emitter and recievers…

It would be in 3 pieces :

– A tube around which we will put the leds (on the upper part of the wand).

– Another tube surrounding the first one (#inception) for protection and beauty.

– A handle with indications where to put your fingers.

Seems a bit abstract now, but I will publish a picture as soon as it will be printed with 3D printer from Telecom Robotics (thanks!).

While Aïmen is finishing the design, I’m now taking care of IR transmission and building debug tools to see how far the signal can reach.

Greetings from Vienna

I have arrived to Vienna yestarday, I’ll stay there for a week. I’ve already took my development card from my luggage, at least it was not hurt during the trip.

The hostel had the good idea to block github.com (why only github ?) so I had to use a old vpn account to be able to check out Expelliarose wiki. I have added an alimentation section as recomended by Alexis.

I also continued developing fonctionality for the STM32 assignment. It is now able to enable and disable a led throught button interupts. However, the subject specify that an anti-rebounce feature should be added, so I implemented a timer that allows only one interrupts every 20ms, it seems correct, let’s hope it is enough.

Auf wiedersehen,


On our way

Now we have designed the (almost) final game scenario. In fact I’m rather impatient to play it now !

I’ve searched throught Sparkfun to see how we could power our system using usb. I think I have a few idea, moreover a lot of Sparkfun components’ diagrams are online, so we could just inspire from them.

At last, we discussed about the pssc and found a minimum gameplay to reach as a first main goal, just hope that we can achieve it ! Using trello is very convenient, I’d already used it during BDE campaign, I’m just wishing it will give us more luck.

See you

back to business

We now have a new name for sorcery : expeliarose ! Hoping that everyone’s got the reference…

We are facing a lot of different problems : how to aim other sorcerers with you stick ? Propably using IR, but we will have to insert it in a nice way on our device. Moreover the conception of sitck will certainly be made with robotic’s 3D printer (thanks guys!), but nobody in our group made 3D conception (except a few solidworks a looong time ago). Well we already have filled trello boxes to acheive the right definition of our project for friday.

I also fought for long hours with archlinux and f*cking UEFI boot to now have a good work environment. Using Anatole advice, I used I3 as tile manager and it seems to be a good deal.

Also began STM32 project, it is on his way…

See you