Category Archives: LU

Successfull 30th Chaos Communication Congress video streaming

The traditional live transmission of the biggest hacker congress in europe has been sucessfully run during the 4 days of the conference.
The 30th anniversary of the congress had for one no motto as was explained in the opening keynote. The hacker world is speachless after all the revelations by E. Snowden. Many talks also had the surveillance state as subject.

This year we our couches were set up in a nice seating arrangement and showed the main stream on the brand new 135″ projection screen. This must have been the most cosy setup of all Congress Everywhere stations.
Some streams could be shown in the second room if people did not get a consensus which one to watch.
The space was open for the whole duration of the transmissions and attendance was varying between 3 and 12 people.

Huge 135" screen with lots of couches for your viewing pleasure

Huge 135″ screen with lots of couches for your viewing pleasure

Our special room arrangement for conference transmissions

Our special room arrangement for conference transmissions

Christmas Market 2013

It has already become a tradition that syn2cat is present at the annual Strassen Christmas Market. This year it was on 13th and 14th december. Trying to be innovative and present every year something new, we had the ultimaker at our booth.

Building team happily opening the booth

Building team happily opening the booth

After the last year’s success, there were also glowpins on sale, which gained again huge popularity. Additionally the new RGB glowpins were a great success and the complete stock was quickly gone. More next year!  We also had Club Mate and Club Mate winter edition which we did heat to make it into Christmas style mate tea.

The most blinkenlighty place on the market.

The most blinkenlighty place on the market.

The ultimaker was busy all the time printing various Christmas themed objects we had previously downloaded. Visitors could draw their own shapes via doodle-3D and print them in about 5 minutes.

Doodle 3D in operation

Doodle 3D in operation

lots of curious kids

lots of curious kids

We had great fun

We had great fun

 

Science Festival 2013

George1-300x207Science Festival 2013′s main theme was water, so syn2cat researched how we could hack something as common as H2O. We found that non-newtonian fluids were a great subject, especially corn starch mixed with water (called oobleck). The planning consisted of preparing several essential experiments and some accompanying optional bonus items.

We would like to thank the organizers for believing in our cornstarch pool, which we initially feared wouldn’t be possible because of the accompanying mess.

first classes getting messy with cornstarch

first classes getting messy with cornstarch

The science festival is in two parts, the first 2 days are reserved for school classes where each booth presents their experiments to classes. The kids could mix their own cornstarch solution (use 2 cups of cornstarch, one cup of water) and then get their hands dirty while experimenting with it’s surprising properties. After this first part, hands got cleaned and we put the previously created mix on a vibrating loudspeaker to show the cornstarch monster.

the cornstarch monster

the cornstarch monster

To add to the non-newtonian family, another setup showed soap behaving strangely. The Kaye effect with shampoo ejecting streams sideways and dish washer drops whizzing and jumping around almost frictionlessly.

the Kaye effect setup

the Kaye effect setup

the Kaye effect in all splendor

the Kaye effect in all splendor

We stumbled across the soap droplets’ behavior while testing soaps for the Kaye effect. Is this a new discovery?

During the weekend the Science Festival was open to the whole public. That was the moment we wanted to have the anxiously awaited corn starch pool set up.

setting up the cornstarch pool

setting up the cornstarch pool

in goes the cornstarch mix
in goes the cornstarch mix

creating a nice pool

creating a nice pool

 

Around 8000 persons showed up, mostly parents with their children. We had the cornstarch monster running in continuous mode with a manned station where kids and adults alike could touch the white mass.

cornstarch pool running

cornstarch pool running

From there we invited everyone to go check out the red tent (thanks to the organizers for providing this) where they could “walk on water” (this was not done for the school classes).

On Saturday, the weather was sunny and we could run the cornstarch pool all day long. I would like to especially thank Thierry who stayed almost the whole time in the cold at the pool. At noon Gunstick went to radio Ara to participate at the syn2cat Let’zHack show to talk a bit about his impressions of the festival.

Besides this, the soap setup was also running, with accompanying video from University of Twente in the background. The video became essential on sunday as all our shampoo became thick and full of bubbles, killing the effect. Contrast this with the soap drops, which stayed in shape and kept on happily jumping around.

visitors at our booth

visitors at our booth

crowds flowing by

crowds flowing by

people walking in water

people walking in water

the pool was outside

the pool was outside

On Sunday the morning was rainy, so we didn’t run the pool then. The afternoon the weather got better with some sunshine and we  had again a great success! Especially with the kids, who had great fun running across time after time after time. Because of the weather we did not ask people to remove shoes, and at some times shoes needed to be rescued before being sucked to a “corn-starchery” grave. As the oobleck is mostly solid under the stress of  someone walking on it, shoes did not sink and the occasionally falling child could be lifted off with almost no cornstarch traces on the clothes.

Then came the end of all it and we managed to load everything into just 2 cars. After a nice meal we unpacked at the hackerspace. The following days more and more science festival stuff magically disappeared into the various storing capabilities of our beloved space. Just some white corn starch traces show that there was something going on.

Car packed

Car packed


makerbot thingomatic build-up

At hack.lu we got a great present from kd85: a brand new Thing-o-matic Makerbot, complete with heated, automated build platform. As soon as the conference was over, we rushed to our beloved space to start putting it all together.

Here are some pictures taken during the construction. Most of them from unpacking, after that, hands were busier building the machine than taking photos!

donator

donator

unboxing

unboxing

checking all material

checking all material

smell of lasercut wood

smell of lasercut wood

get instructions online

getting instructions online

here we go

here we go

looks cool

looks cool

halfway through

halfway through assembling the body

electronics to do

electronics still to do

hardware build finished

hardware build finished

What to say about the buildup? From Kenn’s perspective, putting together the wood structure, it was an absolute joy. Georges had to work a little harder to with the twiddly bits in the extruder, but hackers always love a challenge! And of course no kit is complete unless, well, it’s incomplete: there were magically some nuts missing, but a good hackerspace always has this stuff around. The extruder needed partial disassembling, because the misunderstanding of a couple English words made a basic error possible. Plus, some cables were short and had to get an extension. All in all, the build was done in about 2 days and it looks great. Thanks so much to kd85 for gifting us this wonderful machine.

Now to get the software going and commission our brand new makerbot!

syn2cat at hack.lu

Last week we had our booth at the annual hack.lu conference. We showed the ultimaker printing various items. Also shapeoko and some quadrocopters completed the setup. The fog screen was rebuild and displayed the current time in mid air while distributing moisture throughout the big room. A fridge full of Club Mate waited for the attendees who were happy to buy some.  We also arranged a little lounge area in front of the stand which was most of the time in good use.

booth at hack.lu

booth at hack.lu

gears printing

gears printing

fog screen

fog screen

hack.lu lunch

hack.lu lunch

busy times

busy times

club mate selling

club mate selling

lounge area

lounge area

Decrypting network traffic at the hackerspace

MbitVUmeterYou know the VU meter showing the network traffic on our Internet connection. The needle also bounces when the hackerspace is empty. Looking a bit more closely shows that it’s mostly encrypted traffic. What is going on here?

To store our members credentials and information for our WiFi network and our Openduino lock system, we use ldap, a kind of database.
openvpn_logo The ldap server at the hackerspace communicates and synchronises regularly with our master ldap server on the Internet over a permanent ipsec/openvpn tunnel with strong crypto.

Another VPN is the one that only gets activated for the annual Chaos Communication Congress. During the congress, the network at the conference gets extended to the hackerspace with its own dedicated WiFi access point and without any connection to a syn2cat network. Don’t connect to it unless you are prepared to completely reinstall your device and are sure it doesn’t contain any confidential data. On the other side of that tunnel are some black hats waiting for easy pray. Please don’t use syn2cat’s computers to connect there.

ssh
Other pseudo VPNs are those established by our members using ssh to either enter or exit the hackerspace’s network. SSH can easily be used to tunnel a secure connection for any program; see Gunstick’s ssh presentation to learn more. If you want to know how to set up your own VPN, visit a cryptoparty, where you can get help or ask a friendly syn2cat member.

The last category of communications happening without people at the space, and generally unencrypted, are things like Openduino updating the status, computers not being shut down or servers syncing their time from the internet or checking for updates, raspberry pis being left turned on and communicating via internet, etc.

Please don’t run a tor node (client is ok) or freenet inside the space, as it quickly eats up all available bandwidth. This also counts for any peer to peer software. Stop the torrent client on your laptop before connecting to the syn2cat lan.

It is a good idea to always use encrypted protocols, e.g. https, imap+ssl, smtp+ssl — not just at public hotspots, hotels, and conferences, but also at the hackerspace and at home. Even the most secure network can’t fully protect you from a bad guy who wants to sniff unencrypted secrets.

Flying workshop

What’s that in the air? It’s a bird, it’s a plane, it’s a hacker!

That’s right, thanks to the wonders of modern transportation, we all loaded up in cars and found ourselves a grassy field in southern Luxembourg, where we could spend a bit of time learning to fly airplanes. With a trusty trainer transmitter setup, we were able to make a day out of flying all sorts of aircraft.

We had a really great turnout, with Tatiana even biking two hours to come learn how to fly. That’s dedication!

w_IMG_1475Raphael brought his Ascending Technologies Firefly. What a nice machine!

w_IMG_1489Kenn teaches Francois how to fly. Kenn got a haircut right after seeing this photo.

 

w_IMG_1486Marc’s plane was unfortunately the only fatality for the day. On its test flight, the model lost radio link at 100m distance and dove into the ground. The ensuing crash broke a lot of stuff. Remember boys and girls, always test your radio range before flying!

 

w_IMG_1485We recharged our batteries using a car battery. Don’t do this too much, because you’ll run the car battery flat. It depends on the size of the pack, but we only charged about 10 small 2S batteries before switching donor cars.


w_IMG_1488  w_IMG_1491You neck hurts after a little while of always staring up.


w_IMG_1487
 w_IMG_1483But boy are the planes beautiful when they fly!

w_IMG_1490And of course we had a BBQ. Hackers gotta eat!

w_IMG_1492 No day is complete without security showing up and telling everyone to go home. No, seriously, this was part of a test to try to use the TechPod (featured in the picture) to autonomously find a lost hiker wearing a high visibility vest.
w_IMG_1482 w_IMG_1481 w_IMG_1480 w_IMG_1479 w_IMG_1478 w_IMG_1477 w_IMG_1476
w_IMG_1474 w_IMG_1473

 

 

 

 

 

 

 

 

Game evening

So hackers are computer nerds? Think again. We like to socialize, do creative things and build stuff. So what about games? Computer games do not always give that social aspect as with the classic board and card games.

So some fellow syn2catters met last Thursday for a game night.

The chosen game was Munchkin. An monster role playing game pressed into a card deck.

After  explaining  some rules we got into play and learned the rest on the way. Interestingly, the newcomers to this game all became elves, and one won the game even though some more experienced players were there.

 

This experience need a repetition so who’s in next time?

 

Quadrocopter factory

This Sunday we got serious about putting it all together: building our own mini quadcopters.

Kenn gave some insights into the mathematics behind keeping an unstable system dynamically at rest. Same thing as balancing a broom on a fingertip, just that your head does not need to do a mathematical development over 27 pages to do the inverse of the 4D matrix.

No we didn’t do that either. So it was: the transform matrix is A, and to get our values, we need A-1.
Math is cool, it proves stuff that you say is intuitively correct. Like that you need at least 4 propellers, that 2 have to run in reverse, and that those need to be on opposite sides of the same arm. Else A-1 does not exist and your copter is impossible to fly. It’s like the division by zero in matrix. Did Neo do that in the movies?

The build was quite easy as we got several 3D printed parts in the kits Kenn provided.

These parts were printed on a refrigerator-sized 3D printer in an American university, but Guilluame thinks the Ultimaker can build the same parts.

The concept is built around the idea that weight is the biggest enemy to flight. The heavier the UAV, the more energy involved in a crash, and the higher the likelihood of breaking things. So the UAV always needs to be light as possible. Here, the arms are made of carbon fiber kite tubes, held together at a center brace. The brace does not need to be very strong, since the quadcopter only weighs ~150g, which means each arm is lifting ~38g. That’s about the weight of a chunk of baguette bread. Compare that to the tensile strength of the carbon fiber and see that the model is far stronger than it needs to be.

The middle plate is FRP, which rigidly links the carbon fiber tubes together, at the same time as providing stiffness and a handy platform for mounting equipment.

Build a cross, put the base plate on.

Strap motors on and solder the power ends together. Putting the motors on is easy: just some double-sided tape and zip ties. Remember, the goal here is to be crashable, so extra emphasis is paid to having easy to repair assemblies!

While putting motors on is easy, soldering the wiring harness never is. 4 motors have to connect to one battery, which has led to countless variation on the internet, but never one approach to rule them all. At the syn2cat, each hacker went his own way, making a wiring harness to fit the custom direction they’re going with their quads.

Place the battery. Nicolas Petit has a nice paper describing the advantages of placing the center of gravity higher instead of lower.

We use the STM32F3Discovery board, second from left. It’s big, but it’s an awesome value. For $10, each hacker gets a 3-axis magnetometer, 3-axis gyroscope, 3-axis accelerometer, and ARM Cortex M4 processor, with an integrated hardware debugger to boot. Hackers who want to upgrade to one of the smaller boards in the picture will be able to micronize, but at a cost of ~$100.

There is no mount, so it’s Styrofoam and rubber bands. This makes it easy to repair and rebuild.

Kenn also came up with a nice idea to raise funds for syn2cat. Auctioning off bling bling stuff for the copters. There were LED strips, light fibres, better chargers, and an OSD display for putting your telemetry on a video stream.

We got a nice overview of the software by Vinz Kessler, one of Kenn’s fellow developers from Tau Labs. How to get the software, compile and start. And how to connect the controller board.

Now it only needs to get connected to the receiver, and mount propellers.


Then it should fly, if the software is OK. So flashing the autopilot onto the device.

At the end of the night, we had two quadcopters almost ready to fly. Ten more left to finish.

The first flight tests will be this week, and within a couple weeks everyone should have theirs flying. Keep watching this space for upcoming video of 12 sub-$200 quadcopters in flight.

UAV workshop

Our American member Kenn has spent the last months fascinating everyone with his projects on unmanned autonomous vehicles, be they quadcopters or airplanes. So his offer to run a workshop on building your own little quadcopter was extremely well recieved. 12 hackers jumped at the chance and after a few trials and travails, hardware for 12 complete UAVs was finally delivered.

material to build 12 quadrocopters

Last week Sunday, we started hacking our remote controls. They needed to be changed from Mode 1 to Mode 2, flashed to the open-source Open9x firmware, and configured.

This Sunday, it was the tiny little brushless motor controllers turn to be hacked, flashing them with BLHeli in order to make them fit for the needed fast reactions. The flashed firmware can make the ESCs respond an order of a magnitude faster to input commands.

Precision is the word of the day, as good connections with tiny programming pads have to be made, over and over again. To make things even harder, the pads are hidden under heat shrink plastic. This has to be done a total of 60 times, as all the controllers needed  to be flashed (4 for each quadcopter, plus some spares).

Poking at the pads with tiny sewing needles while the board is being flashed is a tricky job. Too little pressure and the connection won’t be good. Too much pressure and the needles can damage the pad. Gunstick came up with a simple contraption built out of legos.

Note that you need those little LEGO guys to supervise correct placement :-)

Every hackerspace needs it’s box of LEGOs.

Below you see how needles are correctly placed and held in firmly by the levers.

This allowed for quick flashing and swapping of the boards. And of course the ubiquitous arduino was there to do the job.

After flashing, the controllers are soldered onto the motors. Half of them upside-down as we need half of them to run in reverse. We’re crossing our fingers on that one.


Never forget to tin the wire leads first. The connections need to be solid.

Meanwhile more flashing is going on.

Yes, it’s using windows. Ye gads!

More views of the controller flasher.