# Projekte
Achtung: Bitte KEINE neuen Projekte mehr hier anlegen! Wir wollen zukünftig nur noch **Project Gallery** on [FabLab Manager](https://fablab.tu-ilmenau.de/#!/projects?member_id=&whole_network=f "Projects gallery") nutzen.
# Vacuum cleaner
My neighbours gave me this vacuum-cleaner brush that didn't work anymore because it stopped spinning. The connecting piece was so worn out, that the "clutch" piece would spin freely inside it.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/img-20250404-091607.jpg)
I 3D-scanned the clutch with our CR-Scan Raptor in blue laser mode. For this to work, you need several tracking points around the object.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/img-20250404-105348.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/img-20250404-105332.jpg)
Here you can see the result of the scan.
I used blender to postprocess the data into a positive part and a negative copy that fits into the center of the brush.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/blender-ys3orrrceb.png)
In order to make it removable, I drilled a hole through my printed piece and the brush, in place of one of the screw holes. Now I can securely fix the part in rotation, but still dissasemble and replace it if neccesary.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/PJHimg-20250404-140617.jpg)
This is what the finished result looks like:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/F9jimg-20250404-141801.jpg)
[staubsauger\_fix\_01.stl](https://unikat-ilmenau.de/wiki/attachments/153)
# Otto
Our fellow researcher M. Sc. Yonghuan Fu from the [Fachgebiet Angewandte Nanophysik](http://www.tu-ilmenau.de/angewnano) contacted us because he wanted to build a little robot in order to promote his sodium batteries. Detailed information can be found at this link：[https://fablab.tu-ilmenau.de/#!/projects/robots-powered-by-all-solid-state-sodium-ion-batteries ](https://fablab.tu-ilmenau.de/#!/projects/robots-powered-by-all-solid-state-sodium-ion-batteries)This work was supported by FabLab/UNIKAT and Otto Robot Open Source Project.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/large-project-image.png)
# Rückenkratzer
Unsere liebe Reinigungsfachangestellte Susanne hat mich gebeten Ihr einen Rückenkratzer zu drucken. Auf die Frage "Wie soll der denn aussehen?" hat Sie eine Geste mit der Hand gemacht, die ich ungehend mit unserem 3D-Scanner erfasst habe.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/img-20250404-104947.jpg)
Obwohl sie beim Scan etwas gewackelt hat, ist ein relativ brauchbares 3D-Modell daraus geworden.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/rueckenkratzer-01.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/img-20250404-104930.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/VM4img-20250404-104922.jpg)
# HSF-Radio
Our beloved Student radio HSF is celebrating its [70th birthday](https://www.tu-ilmenau.de/aktuelles/der-im-fruehjahr-1950-als-betriebsfunk-der-damaligen-ingenieurschule-ilmenau-gegruendete-sender-radio-hsf-feiert-in-diesem-jahr-sein-70-jaehriges-bestehen-damit-sendet-der-hochschulfunk-schon-laenger-als-ard-und-zdf-mittlerweile-existiert-mit-dem-1991-gegruendeten-hsf-studentenradio-ev-ein-gemeinnuetziger-verein-in-dem-sich-ueber-30-radiomacher/innen-neben-ihrem-studium-an-der-tu-ilmenau-engagieren-nachdem-die-grosse-geburtstagsfeier-corona-bedingt-in-diesem-jahr-nicht-stattfinden-kann-findet-stattdessen-eine-sondersendewoche-statt-vom-13-bis-17-juli-soll-taeglich-von-9-bis-24-uhr-das-jubilaeum-gefeiert-werden-dabei-wird-auch-in-einer-eigens-konzipierten-taeglichen-sendung-die-geschichte-des-senders-rekapituliert-und-vorgestellt-zu-einer-taeglichen-talksendung-sind-gaeste-wie-der-ilmenauer-oberbuergermeister-dr-daniel-schultheiss-der-direktor-der-thueringer-landesmedienanstal)!
[https://www.radio-hsf.de/](https://www.radio-hsf.de/)
As a present we wanted to develop a HSF-Radio Soldering kit.
The first attempt was to try this this radio-kit from [Aliexpress](https://es.aliexpress.com/item/1005008255013308.html?gatewayAdapt=glo2esp).
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/img-20250408-183009.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/img-20250408-182957.jpg)
# MIoTy
Thanks to Tim Hemmecke, we had a little [MIoTy](https://www.iis.fraunhofer.de/de/ff/lv/net/telemetrie.html)-Workshop in our FabAcademy [Networking class](https://academy.cba.mit.edu/classes/networking_communications/index.html).
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/img-20250410-100515.jpg)
This is the boards we designed, milled and programmed.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/img-20250410-100539.jpg)
Another board made by Fraunhofer-Institut.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/img-20250410-100810.jpg)
The mioty Gateway.
# Projektseminar Prof. Husung
We build two prototypes for the Projektseminar of Prof. Husung.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/koay-01.jpg)
This one, by Zhi-xi Koay, included milling the base on the carvera,
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/mustafa-01.jpg)
while this one from Mustafa Alan has a laser-cut base from Acrylic.
# Sensorhalter
Für Herrn Bernd Klose haben wir diesen Sensorhalter gedruckt:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/bernd-klose.jpg)
# Gravierung USB-Hubs
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/belkin-usb-hubs.jpg)
# RC-Van
Die Studenten Benedikt Feit und Marvin Gärtner haben dieses ferngesteuerte Auto als modularen Bausatz entickelt:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/bene-marvin.jpg)
# Fab-Logo Brandeisen
For decorating our Buns, we made a branding iron in collaboration with the [Lehrwerkstatt](https://www.tu-ilmenau.de/universitaet/quicklinks/zentralinstitut-fuer-bildung/lehrwerkstatt).
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/12fbrandeisen.jpg)
The first prototype was milled out of recycled HDPE-Plastic (Carvera) while the final pieces were milled out of brass on the 3-axis CNC in the Lehrwerkstatt.
# Repair of Headphones
Jakob Lerch: Repair Hinge for Headphones ATH-MK40x
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/HB6repair-hinge-for-headphones-ath-mk40x.jpg)
# Reparatur Delonghi Siebträgermaschine
Using our Carvera 3-axis milling machine, we milled an aluminum piece in order to fix this Espresso-machine:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/adrian-kriegel-delonghi.jpg)
# PCB für ein Mischpult
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/scaled-1680-/thore-verstaerker-01.jpg)Zusammen mit Thore Lencer haben wir ein einseitiges PCB für einen Verstärker gefräst.
Grundlagen analoger Schaltungstechnik; Prof. Sommer
# Ersatz-Zahnrad
Ein weiteres Projekt für unsere Susanne ist ein Ersatz Zahnrad für einen [Dönergrill-Drehspieß](https://www.otto.de/p/rachs-kochwerk-doenergrill-drehspiess-grill-spiess-elektisch-haehnchen-1400-w-inkl-schaschlikspiesse-360-bis-zu-2-kg-fleisch-S0B9O0QC/#variationId=S0B9O0QC1ELC)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/unbenannt.jpg)
The most difficult part was getting the gear right. I measured the inner and outer diameter of the gear (Kopfkreis Ø 25 mm and Fußkreis Ø 14 mm) and then asked DeepSeek for the modulus of the gear. The first time I didn't give it the amount of teeth and it gave me a long but useless answer. The second time it told me that the module is 2,5. Which turns out to be perfectly right. I used the Gear-Module in FreeCAD to model this gear:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/grafik.png)
I asked DeepSeek again just for completing this documentation, but it completely messed up:
> My cog has an outer diameter of 25mm and an inner diameter of 14mm. The gear has eight teeth. What is the module?
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/yY6grafik.png)
# Jarni's robots
Jarni Castillo printed some parts for his modular robot
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-04/jarni.jpg)
# 2leggedRobot
In collaboration with [Prof. Dr.-Ing. Gerald Schuller](https://www.tu-ilmenau.de/universitaet/fakultaeten/fakultaet-elektrotechnik-und-informationstechnik/profil/institute-und-fachgebiete/fachgebiet-angewandte-mediensysteme/team) we are trying to help with his two-legged robot.
[https://github.com/TUIlmenauAMS/2-Legged-Robots](https://github.com/TUIlmenauAMS/2-Legged-Robots)
[2legged\_robot\_01.blend](https://unikat-ilmenau.de/wiki/attachments/112)
We are working on pressure sensors for the feet.
We wanted to try a material from [Junior-Prof. Hongye Sun](https://www.tu-ilmenau.de/universitaet/fakultaeten/fakultaet-elektrotechnik-und-informationstechnik/profil/institute-und-fachgebiete/fachgebiet-funktionswerkstoffe/team) as a pressure sensor, but unfortunately the long-term signal repeatability does not seem to be consistent enough. We will continue to work with her and her team to hopefully improve the results.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/img-20250623-160308.jpg)
After cleanup
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/img-20250623-153832.jpg)
labeling the wires
hotglue leftovers
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/img-20250623-150600.jpg)
original situation
cleaning connectors
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/img-20250623-154859.jpg)
hotglue / solder - mess
Name
link
Datasheet
Analog read with digital pin:
[https://www.raspberrypi-spy.co.uk/2012/08/reading-analogue-sensors-with-one-gpio-pin/](https://www.raspberrypi-spy.co.uk/2012/08/reading-analogue-sensors-with-one-gpio-pin/)
# Formulierung dehnbarer leitfähiger Tinten für 3D-Drucker vom Typ Direct Ink Writing (DIW)
[Junior-Prof. Hongye Sun](https://www.tu-ilmenau.de/universitaet/fakultaeten/fakultaet-elektrotechnik-und-informationstechnik/profil/institute-und-fachgebiete/fachgebiet-funktionswerkstoffe/team) arbeitet mit Ihren Kollegen an einer[ Formulierung dehnbarer leitfähiger Tinten für 3D-Drucker vom Typ Direct Ink Writing (DIW)](https://www.tu-ilmenau.de/universitaet/fakultaeten/fakultaet-elektrotechnik-und-informationstechnik/profil/institute-und-fachgebiete/fachgebiet-funktionswerkstoffe/forschung)
In the fablab we tried to help with measuring the resistance of this material with a RaspberryPi Pico.
[2legged_robot_01.blend](https://unikat-ilmenau.de/wiki/attachments/111)
Resistance Measurement
For doing the “Multi-channel-measurement” of your Resistors we used the https://www.raspberrypi.com/documentation/microcontrollers/pico-series.html
I just realized that the pico only has 3 analog inputs.
It would be better to use the Arduino Mega, the Teensy4.1, the STM32 Blue Pill or a ESP32
https://chat-ai.academiccloud.de
How can I measure a resistance between 1 and 10 Ohms with an Raspberry Pi Pico using a Voltage divider?
We use the software:
https://www.arduino.cc/
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759764983610.png)
With this sketch:
/*
ReadAnalogVoltage
Reads an analog input on pin 0, converts it to voltage, and prints the result to the Serial Monitor.
Graphical representation is available using Serial Plotter (Tools > Serial Plotter menu).
Attach the center pin of a potentiometer to pin A0, and the outside pins to +5V and ground.
This example code is in the public domain.
https://www.arduino.cc/en/Tutorial/BuiltInExamples/ReadAnalogVoltage
*/
// the setup routine runs once when you press reset:
void setup() {
// initialize serial communication at 9600 bits per second:
Serial.begin(9600);
}
// the loop routine runs over and over again forever:
void loop() {
// read the input on analog pin 0:
int sensorValue = analogRead(26);
// Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V):
float voltage = sensorValue * (5.0 / 1023.0);
// print out the value you read:
Serial.println(voltage);
delay(100);
}
And this electrical setup (we only had a 220ohm resistor):
3.3V
|
[ R_ref ] = z. B. 100 Ω
|
+----+----------------+
| |
[Rx] ADC-Messpunkte
| (A+ und A− an GPIO26/27)
GND
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759765042965.png)
https://chat-ai.academiccloud.de
How can I measure a resistance between 110 ohms and 1 kOhm with a arduino Nano using a Voltage divider?
# Reparatur Bosch-Handmixer MFQ3530/04
Anleitung zum Auseinanderbauen eines Bosch-Handmixers MFQ3530/04
[https://youtu.be/zUCDC8c7Mfw?si=xyCjRCcBSx1NDzej](https://youtu.be/zUCDC8c7Mfw?si=xyCjRCcBSx1NDzej)
[https://www.gutefrage.net/frage/wie-baue-ich-den-bosch-handmixer-mfq3530-auseinander](https://www.gutefrage.net/frage/wie-baue-ich-den-bosch-handmixer-mfq3530-auseinander)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1749220542348.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1749221257856.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1749221345653.png)
Some more pictures of the repair:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1749222437971.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250907-112207.jpg)
This is the electronics still with te broken cable.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250907-112905.jpg)
This is right after cutting off the bad piece of cable and the terminals.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250907-113519.jpg)
I skinned the cables, crimped and soldered them to the old terminals.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250907-114021.jpg)
Here the electronics with the fixed cable are back in place.
# Msys
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1749812818716.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1749812842886.png)
[msys_02.svg](https://unikat-ilmenau.de/wiki/attachments/108)
[MSys.svg](https://unikat-ilmenau.de/wiki/attachments/109)
[Mys v5.f3d](https://unikat-ilmenau.de/wiki/attachments/110)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1750151520560.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1750246319238.png)
Block:
148 mm x 88 mm x 18,5 mm = 241944 mm³
Volume of mold:
241944 - 96361 = 144583 mm³
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1750249508084.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1750252192173.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1750252404493.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1750320068710.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-06/image-1750317959495.png)
# panema
3D Scan of a toy car
# Stempel Bergfest
Short explanation on how to make stamps out of EVA-Foam:
First, the design should be made as a vector-graphic. This could be done in Powerpoint, Illustrator or Inkscape (any software that exports in .ai, .svg, or .pdf).
I'm using Inkscape as an example:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/inkscape-pl216cxlkw.png)
The dimensions should be to scale.
In the next step we mirror the design (horizontal or vertical):
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/bfxojjkuty.png)
In order to engrave the space between the letters, we have to duplicate the box and subtract the text from it. Select the box, then shift select the text and hit "Strg + -" (Pfad --> Differenz)
I gave it a blue fill color for engraving.
I made the outline red for cutting.
Then we go to file --> Save as... and choose [](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/image-1754491004492.png) with the default settings.
In RDWorks we can import with "File --> Import".
Make sure that the dimensions are correct by selecting everything and comparing it to the bounding box size in Inkscape.
These are the settings I used for engraving and cutting:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/x3ustempel.png)
The final result should look like this:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/img-20250806-165727.jpg)
# Handle Lawn Mower
Our neighbour Dr.-Ing. Christoph Baumer gave us a broken handle for lawn mower with the request to fix it.
We made a 3D-scan of it and printed a copy:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/700-219-max.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/700-332-max.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/img-20250827-100829.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/img-20250827-100842.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/img-20250827-100853.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-08/img-20250827-100926.jpg)
The first version was lacking the groove in the handle, so we printed a second one in the right color.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/4032-3024-max.jpg)
This the final working version installed in the lawn mower:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/whatsapp-bild-2025-09-02-um-11-38-17-ebfda133.jpg)
This is the name and brand of the Lawn mower: [LUX 20V Akku-Rasenmäher](https://www.obi.de/p/9588534/lux-20v-akku-rasenmaeher-1-powersystem-a-rm-1x-20-4-33-set-1x-20v-akku)
# Design and 3D Modeling of a Multilayer LTCC Interconnection Platform Based on Einstein Tile
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250908-170554.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250908-170607.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250907-wa0001.jpeg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250906-wa0001.jpeg)
# Audio Tone Control
Thore Lencer, Prof. Dr.-Ing. Ralf Sommer
# GaSt Praxisseminar WS 25/26
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250916-132138.jpg)
Probably our most complex double sided PCB so far.
Size ~60x50mm
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250916-132154.jpg)
We are working on soldering this board with our Reflow-oven.
We want to try making the solder-paste stencil with our vinyl-cutter:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/image-1758200650767.png)
Above is a screenshot from GoSign, our software for the Summa S3 T75.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/image-1758200692402.png)
This is an attempt with a speed of 10mm/s instead of 800mm/s:
The first stencil looks very promising!
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/Tjn4032-3024-max.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/img-20250925-151927.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/img-20250925-152335.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/img-20250925-154737.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/img-20250925-155428.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/img-20250925-155526.jpg)
### Reflow soldering
Placing all components:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/scaled-1680-/xOuimg-20251001-142141.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/scaled-1680-/img-20251001-153336.jpg)
Good settings for perfect TSSOP package and 0,4mm traces copper milling: 0.2mm v bit but insert 0.25mm in modsproject with 0.25 stepover and 4 offsets
Solder mask removal: Solder mask removal bit; Z calibration with multimeter; then step up by 0,12mm and step down slowly if needed; cure UV mask for 5min first, then mill, then final-cure; cut speed 5mm/s; plunge speed 2mm/s, spindle 6000rpm
Drill after solder mask application! Elsewise solder mask gets into the holes and copper can be destroyed when there are thin pad rings
# Miteinander Stärken
We lasercut some "white rings" for the event "Miteinander Stärken" from 3mm Plywood.
The design was done in Inkscape.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/pin-inkscape.jpg)
In order to get it to the Lasercutter I saved the file as dxf\_r12.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/pins-01.jpg)
I used Power=80% and Speed=10mm/s
A higher speed might have been OK as well.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-09/scaled-1680-/img-20250919-152217.jpg)
# Stretch-Sensor
We are working on a little circuit for testing a material developped by [M.Sc. Han Yang](https://www.tu-ilmenau.de/universitaet/fakultaeten/fakultaet-informatik-und-automatisierung/profil/institute-und-fachgebiete/institut-fuer-biomedizinische-technik-und-informatik/bmti/fachgebiete/datenverarbeitung-in-den-lebenswissenschaften/msc-han-yang):
[4](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/scaled-1680-/4032-3024-max.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759751713410.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759751731897.png)
Measurement with Multimeter:
Initial state
110 - 170 Ω
slight stretching
350 - 500 Ω
Higher tensile force
1kΩ
(unstable)
Approximately limited state
9-15 kΩ
(unstable)
https://modsproject.org/https://modsproject.org/
rightclick --> program --> open program --> carvera mill 2D PCB
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759757187253.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759757874429.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759758026634.png)
first test:
https://www.hackster.io/ddami/5-blinking-leds-c29889
https://chat-ai.academiccloud.de
How can I measure a resistance between 110 ohms and 1 kOhm with a arduino Nano using a Voltage divider?
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/image-1759827939234.png)
We tried Rk=330Ω (values too high)
Rk=220Ω (values even higher)
Rk=1kΩ (ok!)
[Sensor](https://unikat-ilmenau.de/wiki/attachments/135)
# Trihedral Corner Reflector
The goal was to build [trihedral corner reflectors](https://en.wikipedia.org/wiki/Corner_reflector "Wikipedia: Corner reflector") to be used in a radar training accompanying the lecture "Fundamentals and Systems of Radar Technology" (FSRT). This lecture is offered by the ["Radio Technologies for Automated and Connected Vehicles" research group](https://www.tu-ilmenau.de/en/favf "https://www.tu-ilmenau.de/en/favf"). New reflectors were required after the FSRT training has been modernized, financially supported by the [examING](https://www.tu-ilmenau.de/universitaet/quicklinks/zentralinstitut-fuer-bildung/ueber-uns/projekte/examing/projektinformation/visualisierung-praktikum-fundamentals-and-systems-of-radar-technology "examING subproject: FSRT training") project.
## Analysis
A trihedral corner reflector is basically made of three equal right-angled triangles. The first task was to define the length **a** of the legs (cathetus).
The reflector shall work in a frequency range of ****77 GHz to 81 GHz****. This corresponds to wave lengths of approximately 3.7 mm to 3.9 mm. Hence, any leg length a that is significantly larger than 3.9 mm is will be okay. However, the corner reflector shall still be handy and ****lightweight**** such that anyone can hold it easily. For the following analysis, we used the center frequency of **f** = 79 GHz.
Let c0 denote the speed of light (in vacuum). Then, the free-space radar cross-section (RCS) **σ** can be computed as follows.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/jJbgrafik.png)
For more details, see [here](https://www.radartutorial.eu/17.bauteile/bt47.en.html "radartutorial.eu: corner reflectors").
We chose *****a***** ****= 69 mm**** which results in an RCS *****σ***** ****≈** **6.6 m²**** (6.5932... m²). We chose this value since the rounded RCS of 6.6 m² (rounded to one decimal place after the comma) would require a leg length of 69.017 mm, which is sufficiently close to an ****integer value**** (69 mm). Additionally, 69 mm is more than 10 times larger than the maximum wavelength of 3.9 mm.
## Building
### 1. Building a jig
The final reflector is made of copper-coated plates that can be used to create [PCBs](https://en.wikipedia.org/wiki/Printed_circuit_board "Wikipedia: PCB"). For each reflector, three right-angled triangles are have to be cut out and glued together. To make the gluing process easier, we first designed and 3d-printed a jig.
The jig has several cutouts. These are used to glue the triangles together. The jig is made for plates of 1.6 mm thickness. The FreeCAD files and STL files are attached to this page.
### 2. Cutting the triangles
The triangles were cut out using a [CNC mill](https://fablab.tu-ilmenau.de/#!/machines/aafrase "Unikat: Makera Cavera").
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/milling.jpg)
### 3. Gluing the triangles
The triangles are glued together by inserting them into the jig and fastening them using clothespins.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/zIugrafik.png)
The glue is applied from the back through the holes. Once the glue is set, the clothespins can be removed.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/T2tgrafik.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/Zd2grafik.png)
Anywhere the glue touches the jig, a knife with a sharp blade (e.g., a cutter knife) can be used to cut the reflector free from the jig. After that, some controlled force is required to push the reflector out of the jig. remaining glue can be removed from the jig using the knife.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/ANsgrafik.png)
With the reflector out of the jig, the remaining parts of the edges (where the jig covered them) can be covered with glue. Let this dry.
## Aftermath and findings
1. The jig was indeed helpful when gluing the triangles.
2. One could design an extra inner part for the jig, which holds the triangles more firmly than the clothespins.
3. The glued reflectors still have small gaps between the triangles, since it is hard to get the edges of the triangles really tightly together.
4. The glue is rather thick, which could make it hard to mount the reflector into some other object. Possibly, one could create a flat surfaces by cutting off the excess glue with a sharp knife.
5. In order to create a more precise trihedral, it would be better to cut or to mill it directly from a single solid piece of metal or at least create a jig from metal.
# Jetclay Workshop
# Starth
Thanks to Thore Lencer we have a beautiful little Microcontroller-board in the shape of the Starth-Logo.
```
```
# Mobile Prüfungsausstattung
The support leg is broken on two of the [Gaumon monitors](https://gaomon.net/de-de/products/pd2200-pen-display).
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/Q2B61difkfyfql-ac-sl1427-2481845675.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/fuss-monitor.jpg)I modeled the leg in [Autodesk Fusion. ](https://www.autodesk.com/products/fusion-360/overview)The file can be found below the image.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/grafik.png)
[Staender\_monitor v2.f3d](https://unikat-ilmenau.de/wiki/attachments/148)
[Staender\_monitor v2.stl](https://unikat-ilmenau.de/wiki/attachments/149)
I got the colour wrong on the first print, but it should be enough to try it out.
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/imUgrafik.png)
# Grillabdeckung Trabi
Herr Stefan Buchelt hat bei uns zwei Grillabdeckungen für den Trabant gedruckt:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/prusa-slicer-jruxw0sbgt.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/ROs4032-3024-max.jpg)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/trabant-601.jpg)
# Würfel
Würfel by Thore Lenzer
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-10/scaled-1680-/wuerfel-01.jpg)
# DC boost converter
We made a little adapter from a [DC-boost converter](https://de.aliexpress.com/item/1005005235933533.html) to USB-C for Yonghuan Fu:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762269517806.png)[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762269597179.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762269774263.png)
KiCAD-files:
[boostconverter\_01.zip](https://unikat-ilmenau.de/wiki/attachments/147)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762329112470.jpg)
from 1V to 4.8V
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762329338079.png)
[Recent Advances in Developing High-Performance Anode for Potassium-Ion Batteries based on Nitrogen-Doped Carbon Materials](https://onlinelibrary.wiley.com/doi/full/10.1002/smll.202406630)
# Meassuring Scale Engraving
I engraved a scale onto some PLA prints. They will be used to more accurately meassure the position of a Hall-Sensor i will be using as part of my Bachelor Thesis.[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762520236465.png)
# Fabi
Our Fablab Mascotte Fabi:
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762780186567.png)
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762780243385.png)
[fabi_02.svg](https://unikat-ilmenau.de/wiki/attachments/154)
# Lighter
Sparsh made a goodbye present for Ferdi: An engraved Zippo-Lighter
[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/image-1762793786356.jpg)[](https://unikat-ilmenau.de/wiki/uploads/images/gallery/2025-11/XFJgrafik.png)
[lighter.f3d](https://unikat-ilmenau.de/wiki/attachments/155)
