BreathUp, bad news


Since Monday, I have added a detection to know if the user switches off the Bluetooth of his smartphone when exchanges with the Bluetooth module were launched. I also fixed errors.

Today, BreathUp received the PCB. However, there were some problems. Indeed, when we have connected the battery on the PCB. There were components which became warm. After investigations, we found errors with the imprints of the LoRa component and the regulator of tension. For the second error, it seem to be not very difficult to correct it with a patch. But about the first, it will be more difficult 🙁 .

Now, I will begin to work on the IMU driver.


pimp my git

hi everyone,

today we, all together, SwARM, like a family (with some issue maybe…) have entirely reviewed our git history of our features to clean our git deposits.
It was very painful but we learned a lot about git (like git rebase) I feel like an historian right now !!
We also started to merge our finish features in dev branch and use a pull request system to do so.

I’m quite exhausted but happy of this work. I also reviewed Paul’s push request which he restarted a few times before being accepted ^^

Also I’m progressing on the IMU part but I feel that I’m stuck with a little problem on I2C transmission : signal don’t appear on the signal analyser but the code seems correct. Even Alexis didn’t find why it didn’t work. Still digging…

And the surprises of today : secret Santa !
Paul organized of secret Santa party for rose attendant which was a very cool idea ! Benoît offer me a wonderful glass and I’m very pleased of

Paul organised also a dinner in a restaurant “café d’Italie” which was good. Thank you very much for your wonderful ideas

That’s all for tonight 🙂

Doing some maths for last time of my life

Hi everyopne,

I have done my last math exercise for last time of my studies (I hope) :
first I passed MDI210 (with 10/20 but it’s something), meaning I don’t need maths UE anymore and…

it's something

it’s something

Then I proposed maths formulas to resolve robots positions with only 3 beacons positions and relative distance between robots and beacons :

let’s assume three beacons, representing an orthogonal reference : P1 : origin, P2 : x axis, P3 : y axis
P4 robot position : what we are searching for. Lets assume Xn and Yn the coordinates of Pn.
Rn : the distance between Pn and P4 : Pn radio radius, position possibilities of the detected robot

X4 = ( R1^2 – R2^2 + X2^2 ) / 2 * X2
Y4 = ( R1^2 – R3^2 + X3^2 + Y3^2 ) / (2 * Y3 – (X3 / Y3) * X4 )

with robot on P4 with coordinates (X4, Y4)

What do you think about my incredible maths ? 😉

I also progressed on the IMU part, I understand the interest of using Stream in ChibiOS for debug messages because it is an abstract layer and I can used it on serial connection, or serial over usb of even with socket !
I also founded some MPU drivers on github that I will use / port on Chibios.

That’s all, good night 🙂

SwARMaximum Precision

Hey everybody,

This week I worked on the imu. I also start porting my led program on ChibiOS. You can see below my E407 with beautiful add-ons : the IMU and a 8 leds strip.
I am little bit late on the IMU because I would have liked to finish this part this week-end but it seems I will finish it next week.


Thursday we measured (with Arnaud) the precision of the decawave. We panicked a little bit because we had around 20 cm precision. Until I suggest we used them vertically. We have now a precision around 2 cms (5cms max) !!!

So we changed decided to connect the DWM1000 to the board using cables and a micro-match connector to fix the antenna vertically and to have the board horizontal.

I also provided to my team (and to the others) a configured, cleaned, basic version of ChibiOS for the boards (p407 and e407) we use to test our programs. The code is now on Github

Next week as I said I would like to finish the IMU and the leds part and also to help Alban on OpenCV and the boids.

That’s all. Good night 🙂

SwARM : rediscovering git

Hi everyone,

I worked mostly on the integration of ChibiOS in the repo today.
In fact I learned how to add a submodule in a repository which is very helpful. SO I added ChibiOS as a submodule in imu branch with a very light configuration for the TP boards.

We decided also to re-introduce the camera in the project because we are not so sure about the decawave precision. So Alban and I will work on that part.

I would like to finish the IMU part by the end of the week.
I would also like to create a simple “how to” for submodule for my co-workers. 🙂

That’s all. Good night

SwARM back to work

So I finish my Athens week, which was great. I worked on I2C protocol : it helps me with the IMU communication.

I started to look into the IMU documentation to see how to create the driver in ChibiOS.
I would like to finish this by the end of the week.

Concerning the robots location detection we might need to re-introduce the camera and picture processing. So I will work on openCV maybe next week.

That’s all 🙂

Athens Week : SwARM is getting bigger

Hi everyone,

I’m right in the middle of the Athens week which is great. I’m learning to make some Linux Drivers which is cool. I’m working on an accelerometer and the I2C protocol. Those knowledge will help me for the IMU in SwARM 🙂

Let’s also welcome Alban who joined our team this week. He will work mostly on the software part, and for know he’s on the boids : how to configure bots to have an emergent behaviour.

I’m working on the IMU part as I said, and I have to produce a test code on ChibiOS to test our IMU.

That’s all folks.

[SKATEway]Post 8


Unfortunately the end of the week was as productive as the begin. I have not enough time to keep the project above the surface. I am currently in a compressed work week with three exams. I know it’s not an excuse. So this week in addition to the challenge, I only order this IMU 6 Degrees of Freedom to test the angle capture.