PLUME – Work in progress

Hi everebody,

It is been a long time since I wrote something on the website. However, I worked this week. Indeed, the purpose of the week was to choose the components for our project. We decided to focus on the receivers because the architecture of them are more complex. To help us to design the amplification of the signal receive is the coils, we met some experts and teachers of our school. They guided us in our researches.

So, we have two possible architectures for our receivers. One of them is based on the use of a low noise amplifier, a programmable gain amplifier and an ADC. The second is to use a component, an Audio Codec, that includes all these features. However, we didn’t manage to choose one of the possibility. Moreover, we worked on the whole architecture, so we choose our microprocessors, our battery and some other stuff.

Now, we may begin to draw our schematics on Expedition PCB.

To be continued…



This week was all about getting our project straight. Deadlines were approaching fast, and we had yet to choose our components. It still needs adjustment but it’s going well.

On a second hand, I had the task to use a HBridge to get the emitter coils to work. However, we still have to determine if we will use an audio amplifier or an HBridge, so I’ll work on the HBridge this weekend.



RoseOnRails – LEDs and Rails

Yesterday night, Alexis managed to control the LEDs with a STM32 discovery.
We then pierced a rails segment and stuck the strip under it to see how it all worked out !

In fact, it was quite easy to have the strips fit under the railway, and the result is mesmerising … see for yourselves!

However, the way the LEDs were controlled for this test, does not enable us to have other threads in our programme because we need a quite precise timing to send information to the LEDs strips.

What we will do is :
Transfer our data (LEDs colors) to the external port of our development board through DMA and send the information from the board to the LEDs strips thank to SPI.

RoseOnRails – A new lead regarding our position issue!

Hi everyone,

We have a now lead for our train positionning issue. We would like to keep certain LEDs lit up on the railway. Each of those LEDs would be landmarks and have different colors. The color of those LEDs would be detected thank to color sensors placed underneath our locomotives, so that each locomotive would be able to know its position when they run on those LEDs.

As  a matter of fact, we don’t need to know the position of the locomotives at every single moment, this information is only useful when a locomotive runs above a LED which is part of the game.
As we’ll know which of these LEDs wil be lit up, the train will be able to count the LEDs they run on with regard to the last landmark they were on. Consequently, this system will enable us to know above which LED the trains will run when they do so.

The only thing we need to implement this system now are color sensors. I have looked  up the color sensors models on the internet and have reduced my choice to 5 of them. I just need to find the right one today!

Have a nice day!

Plume – Communication Challenge


After a long time I’m back finally. The last 4 days, I spent a lot of time on my card to prepare the communication challenge. Well, it was not so simple. But the ordeal is over. Now I refocus on the project.

To be continued..

PLUME – Lab Work

Live from A406: I’ve finally finished my TP.

Good night. 🙂


RoseOnRails and STM32

Hi everyone!

Monday, Noémie and I worked on our LEDs and on the magnetic we could us to detect the position. Some things to remember from this day. We order 30m of  LED strip which represent 900 LEDs ! We’ll receive these strips by 7 days. Concerning the Hall effect, we’ve learnt there are two kinds of sensor : one which detect a tension proportional to the amount of current we put through our coil and the other is kind of binary which detect when a threshold is reached. We’re going to use this last type in our train to identify above which coils is our train by modulating the current we’ll transmit binary identifiers.

Concerning my lab work I’d almost finished the serial port over usb on Monday and confirmed it was working properly by doing some tests with the shell implemented through the serial port. I’ve also had the possibility to turn on and off the buzzer through the shell.

Currently, I’m trying to implement the possibility to make a TCP to a web server on my board. I’m also looking through some documentation in order to take part in the conception of my group’s PCBs.

Plume – Mario 8bit buzzer :)

Today big progress on my lab work. I manage to arrive to the nicest part of the work ; use the buzzer. 🙂 No, it is not the the most difficult thing, but playing Mario / Tetris / Megaman 8bit on the card is very funny and a little bit useless.

Otherwise, I FINALLY calculate the capacity to use on my transmitter assembly. I’m going to try tomorrow. Well, I go back to work on my card, and my choice of amplification chain for our project.

Good evening.



PLUME – The transmitting coil + Serial Over USB


After an intense weekend, here is a summary of chat I did.

On my lab work , I advanced on the use of serial over USB. After some unfruitful hours, to try to understand how ChibiOS works, I managed to activate the serial communication over USB. So my card is finally recognized as an USB device. It now remains to me to implement a shell via the advanced functions of ChibiOS, to communicate and control my card easily.

About the Plume project, whereas I was following the work of MarcO and Olivier on the receiving coils , I worked on the transmitting coil. Indeed , we must find a way to power it efficiently and with enough intensity to generate a strong magnetic field. Thus, my present solution is to use an H-bridge for generating a slot signal for energizing the coil. I am trying to think to add a capacitor in series to create a resonant LC system with a high Q. I now need to choose the capacitor.

It also remains to check that this arrangement is viable by testing. After quick tries, we are able to transmit and receive a usable signal on 1m. This is for the weak point, but we think we can improve this value.

So I ‘m planning to re-analyse the razer hydra to understand how the signal is generated. Unfortunately, their PCB is unclear and I can not find documentation about some components.

On the other hand , I began to think about the choice of the components that we will use (alim, charge controller , … )

Finally, with the help of Benjamin , I have started to play with the BLE card and LEDs. 🙂

Good evening .


LEDzep and work

Since my last post, I’ve been quite busy preparing Friday presentation about 802.15.4/Zigbee with Adèle, studying, getting the damn green LED of the Olimex STM32P407 board to turn on, and various Rose related occupations.

The week end will be entirely occupied with Monday first LEDzep presentation, which I expect to be amazing.

I took some time to make some equipment research hüpfburg mit rutsche kaufen (camera, LED, motors etc), and some sketches, maybe a bit imaginative with the scale, but the purpose was only to give an overall visual description of the project.

Structure sans le ballon Structure avec ballon



Cool stuff of the day : I just received five white 90cm latex balloons I ordered a few days ago in order to do some tests.  Each weights around 35g and inflates quite easily. Here it is, only inflated at two thirds of their maximum diameter, because my lungs were tired. It is closed using only a simple clothes peg. The bananas are for scale comparison

Latex balloon !