Archive for the ‘Project’ Category

This is really incredible – WASP is a cool Italian Company developing 3D-Printers with a vision to support people with it (3D print in architecture) to make the world a better place. That’s where their name comes from: World’s Advanced Saving Project.

IMG_6122I contacted them to ask if I may get a discount on their printers or a kit instead of a readymade printer (well, you know, I love building things) – because for the Eyecontrolled Wheelchair and my next project, the 3D-Scanner for Magnetic fields, I needed to print a lot of designs during the development process.IMG_6995

Marino and Stefano from WASP were so amazed by the project, that they decided to send me one! When I got their answer by mail, it was extremely hard to remain calm and not frak out due to happiness – I was in school that time (yeah, smartphones and schools – a combination most teachers do not like)

THANKS a lot to the WASP-Team

Bundessieg_Arbeitswelt Hello everyone! The German final is now two weeks ago but I probably  hadn’t any time to inform you about it. These five days were so impressive  and exhausting!! But we won one of the first prize!!! That’s really cool and  I  still can’t believe it! After the competition I thought I could just relax –  but      quite the contrary! We’ve got a lot of more attention then we  thought!! This    project is on display on really cool blogs like Hackaday,  Adafruit, Raspberry  Pi!!!! I’m very proud of it!!

After the competition has ended, we want to work on! Because there are so many possibilities! We already got some requests of disabled people or people caring for them!! This is our biggest motivation! We will translate our documentation in english and we will clear out the python code. When we are ready, I will publish all the things you will need to build it yourself 😉

Next week we will attend the German Final of Jugend forscht – after we have won the local and regional competitions. We also got a special prize for our project because it is an innovation for disabled people.

Jugend Forscht Landeswettbewerb 2015  Jugend forscht Fachgebiet Arbeitswelt Stand-Nr.: A-03 Auge steuert Rollstuhl - Eyetracking mit openCV Teilnehmer:  Links: Myrijam Stoetzer (14)  Rechts:  Paul Foltin (15) Schule / Institution / Betrieb:   Franz-Haniel-Gymnasium

Jugend Forscht Landeswettbewerb 2015
Jugend forscht Fachgebiet Arbeitswelt
Stand-Nr.: A-03
Auge steuert Rollstuhl – Eyetracking mit openCV
Links: Myrijam Stoetzer (14) Rechts: Paul Foltin (15)

Our project developed with the different levels of Jugend forscht – the higher we got the more sophisticated our design was because we spend even more time in-between working on it 😉

On the local level we had a little model platform performing as a wheelchair – it was controlled by an Odroid U3 (still the best choice, since it is extremly fast!). We build an Arduino aound it to take care of user input (calibration of tracker) via potentiometers and steering the H-Bridge we developed for the  little motors. After we won the local science fair we decided it is time for something bigger – so we went and bough a real wheelchair!

We spend 2 weekends soldering, drilling and 3D-printing and developed everything new from scratch. This time we used the brand new raspberry Pi 2B, because it was supposed to be much faster than the old one and much cheaper than the Odroid U3. And we took motors from window washers from a car junkyard. This time we used relais to reverse and control the motors, since they used a lot (!) of more current than our H-bride could take. Of cause you could develop an electronic solution for this, switching currents of up to 20A each, but we were short on time and wanted to keep the costs down (for easier rebuilding – and we used up the money we won in the first round as a price as well).

Then we won the regional competition – and decided it’s time for more safety: So we build another system that checks for objects in the way. If we would have more time, we would have loved to move to laser scanner, but at the moment this is off limits 😉 Ultrasound sensors may disturb each other if used close to each other, so we decided to take some IR Range sensors and experimented with them. We just finished now – and the competition will start next week…

You can find the paper we wrote for the competition here – we updates the previous version:


Our project is hereby officially licensed under the creative commons licence BY NC, meaning it is free for everybody to rebuild, modify, improve it – as long as you mention the project’s origin. Oh, and of cause you are not allowed to make money with it – it is free for everybody for the benefit of all 😉

Wish us luck for next week’s competition – I will post the results here … 

Thanks, Myrijam.

A view days ago I participated in Jugend forscht again but this time I was grouped in an older range and more serious competition. I teamed with Paul Foltin (15) and we developed a wheelchair that can be steered by command you give with your eyemovemet.  We earned a first price on regional level and are going to take part on the next round – state level – in a month!! Wish us luck!

With this project we want to give disabled people back their freedom to move independently even if they are totally paralized (locked inside their body like ALS does to people). 

DSC06130We modified a webcam to run with infrared light, 3d-printed a custom case that fits cheap safety glasses as a frame and used this to track the position of the iris in the videoframes. You can use control dials to adjust the parameters for the sections of the video that correspond to moving commands. The video display is rationed in sections. You can trigger 4 different directions by looking in the particular zones.

The processing is done on a fast Odroid in Python with openCV since a Raspi is far too slow (we tried that first). Then there is an additional Arduino board that takes care of the control dials and the two H-bridge drives for the motors. It all sits on a board we have build ourselves…

At the moment the wheelchair is just a model (build with the mechanics from the robot platform qfix) but for the next round we want to advance our project by constructing a real wheelchair. Tomorror I will buy a used wheelchair and then we’ll try to attach motors to it.

I’ll try to keep you posted 🙂

You can find the PDF of our thesis here (in German):

Auge steuert Rollstuhl_Jufo2015_NRW_DU_Foltin_Stoetzer


Posted: 8. March 2015 in Project

2014 there also was a contest with the topic informatics. The exercise was to write a programm for two problems. Here is a link to the website

I took part in Jugend forscht last year, which is a national science competition on local, country and national level. For this contest I created a sensor for a washingmashine that can automatically find the right dosis of washing powder. Detergents like washing powder are usually polar and change the electrical resistence of the water. If too much washing powder is used, you get foam, which is air sourrounded by a very tiny film of water and detergents. Theoretically there are much less molecules that can transfer electric current (only the hull of the foambubbles) than in the water. So there must be a way to differenciate between foam and water by measuring the electric resistence. My sensor has 8 electrodes in different hights for scanning the waterlevel and the foamlevel, using an NXT brick from Lego with a multiplexer and a port extender via I2C.

If all detergents have solved the dirt, there is no foam (theoretically). So all you need to do is add detergents vergy gently until foam starts to build up.

So you won’t support the pollution of the environment by guessing the ammount of washing powder needed.

I got second prize in country-level and an extra award for research in environmently friendly technology.

Google Science Fair

Posted: 8. March 2015 in Project

2014 there was an international contest from Google. I took part with a pulssensor which is used for virtual jogging. My idea was that our pulse triggers the virtual position in google streetview, allowing you to jogg googlesciencefair_ms2through the virtual representations of actual landscapes with a body feedback. The faster you move in front of the monitor, the higher the pulse and the triggering.

The sensor is scanning your skin colour. Everytime your heart beats your skin will change red but our eyes are too slow to realise the changing of the skin. So every 3rd time the heart beats the virtual view of streetview is switched further ahaed. Otherwise it would be to fast. The idea is to bring people together – make appointments to jogg virtually and connected through the cloud – and people can discover other countries and cultures. 



Here is the link to googlescience fair 2015: