Busy friday

Last friday was an incredibly busy day for the team. Directly after lunch an outreach activity, a presentation for the Rocket Science at KTH course to be specific, was planned and immediately after that the team was supposed to demonstrate the functionality of the main electronics in the system as well as the software controlling it. However the day turned out well and in the end at least some of us got to celebrate in the usual way (with beers at the Rocket PUB). A more detailed story from the two events follows below.

The presentation for the Rocket Science course has become a tradition, for the second year in row a team from REXUS presented their project at a lecture for the Rocket Science course. Last years presentation, done by LAPLander, led to the recruiting of a number of members  to the current SQUID team. The presentation for this year where mainly based on the presentation given to a number of schools earlier in the spring but does now feature a number of videos which has been recorded during the project (many of which are available on youtube). There where about 60 students audience who listened to the presentation which where given by Me (Gustav), David, Mario and Mikko. The presentation where rounded of by a short desciption of the intended experiment for next years REXUS campaign (see earlier post). We where very glad to see such an interested audience and also that so many students seemed interested in taking part of the mentioned experiment for next year.

The second event for the day was the demonstration of electronics and software for the project. Mikael Inga form Swedish Space Corporation was visiting us to see the progress of the system. The team had been preparing for this for a long time and was looking forward to show the features of the system. A more detailed blog post featuring the different parts shown will be posted later on by Monica. I my self was very satisfied to see that everything worked as planned and also that Mikael seemed satisfied with the progress.

To round of one could say that we had a hectic but successful friday afternoon to bad i did not have time to participate at the Rocket PUB my self…

PCBs soldered!

Written by Monica

So after have received the PCBs, the exciting tas of soldering started…we have 11 PCBs to solder…but for now 3 of them are critical to test and specially to be tested during a helicopter drop test that is coming in the next weeks.

It is worth to let you know that the challenge in this soldering is to handle the components..becuase they are so tiny that any false movement and they will fly and never see them again, specially the resistors and capacitors.. the ones we were used are case 0603 (1.6 mm × 0.8 mm)..

Other component part of the challenge was the FPGA becuase it has 100 pins and of course they must be clean and dont touch the next pin…when you see then by bare eye it looks so good but if you look with a microscope you will be surprised so it is very important to handle with care this component…. in the next picture some components

In the next part I will show you the PCBs as I showed some posts ago …and how they look now.

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Beacon transmitter

It´s now time for me to give you a short summary of the work that has been done concerning the Radio beacon. But I’d first like to give you a motivation of why the beacon is so important for those of you who need a short reminder off the construction of our experiment please take a short look at Så vad är det vi ska göra egentligen? / So what’s all this about then? (please note though that we’ve changed from airbags to parachute for the landing system).

Since all the data that will be recorded after the FFU has separated from the RMU will be stored onboard of the FFU it’s a primary objective to be able to find the FFU after it has landed. To track the FFU two different systems has been integrated into the FFU. The first system is a GPS which receives the current coordinates of the FFU while in flight. The coordinates are then transmitted through a satellite modem and are then received through a web interface. The second system is the beacon transmitter. A beacon transmitter is a consists of a simple radio transmitter who transmits a signal in an devoted frequency. This signal can then be tracked by a simple receiver. The tracker/receiver consists of a simple radio receiver working at the same frequency as the transmitter  and a simple analog meter displaying the strength of the received signal. By pointing the receiver antenna at different directions is simply its possible to track in what direction the transmitter is located.

In practice the system used by SQUID consists of the TX1 transmitter from Radiometrix. The transmitter makes use of a simple quarter wave whip antenna (which in reality consists of a stripped coaxial cable). For the experiment the beacon will be sitting within the eBox while the antenna is attached to one of the parachute ropes. The transmission is done over 169.4125 MHz and is then received by the receiver.

TX1 transmitter

To test the transmitter function a NRX1 receiver, from the same company making the transmitter, has been bought. This transmitter will be integrated into a simple circuit. The idea is to make use of the Received Signal Strength Indicator (RSSI) which is provided by the receiver. The RSSI works by providing a voltage on one of the legs of the receiver which varies depending on the strength of the received signal.  The circuit will consist of battery holder, power switch, the receiver, analogue current meter and a receiver antenna. The analogue current meter will be connected to the RSSI pin and will vary by the signal strength of the voltage provided by this pin.

NRX1 receiver

The testing will start during next week and will be rounded of by the drop test. During next week a simple transmitter circuit will be built including the transmitter, a power switch, antenna and battery. The testing will start of by placing the transmitter in the Lilian wood nearby KTH, the receiver will then be used to try to find the transmitter. I hope to have some more info about the progress of these tests shared to you all during next week.

Layouts done!

Written by Monica

Since some posts ago, May11-Monica and May13-Mark,  we were talking about the electronics design of the SQUID experiment. We were in the process to design,make schematics, make the layout which meant to route and place the components, with all this done we were able to manufacture the printed circuit board (PCB). We did in total 11 different PCBs, all of them double sided and they have six layers where the routing is done. Fortunately we have received the first set of PCBs and now we can start the so announced soldering. The PCBs look amazing , soon we will show them with the components.

Soldering course at DLR

written by MONICA

As I mention in a older post (11 may) I was going to attend a soldering course at DLR (German Aerospace Center, Oberpfaffenhofen,Germany) offered for the REXUS program..and I did attend exactly after the CDR presentation and when I say exactly after the CDR it is literally because the course started at 9am and our presentation finished at 11am so I was a bit late, and my first surprise was to hear that the course was been given in German, so I asked very kindly to the instructor to give it in English and as everybody was comfortable with that the complete course was in english, he also provide me with manual in English and everything so I felt very happy to understand …. so the course started with the basics, theory about process and how important is to clean everything before start to solder… they provided us with a special PCB to solder and some components in order to practice after the theory was given, among the things that I liked more was a tinning process and also the soldering with hot air, it would be amazing to have one of that solders….specially for the surface mounted devices…. very soon we are going to start the soldering of the PCBs , I am sure this course will help a lot 🙂

Soldering course at ESTEC

As I’ve earlier promised  it’s now time for me to give a more detailed story about the soldering course in Nordwijk which I had the opportunity to take part of. The short adventure started with the flight down to Schipol. For once everything worked fine, except a 45 minuets delay, and I arrived at Schipol with all my luggage in my hands. The next step in the trip was to take the train out to Leiden and I just must mention the strange habit of the train company, when paying with card you had to pay another euro for your ticket. Yes Im used to that small shops in Sweden takes out a fee of about a half euro when you want to pay small amount with your card but the train company???

Well after a train trip of 20 min and then a 30 min buss ride I finally arrived to Nordwijk. It was quite easy to find the hotel and lucky me Jack from TElescope where sitting in the dinning room and where kind enough to show me the room i was going to share with him and . The hotel is a bit special since its divided into multiple small houses which are spread out in the town of Nordwijk so tho find your room the first time is not as all as easy as it sounds. Since I was an hour late for dinner I went out to find a place which where still open for service, after some searching I found an italian restaurant down at the beach and goth some great pasta while I enjoyed the sunset view over the beach.
The first day of the training course started early and i and my room mates met the other participants at the breakfast from where we all took the bus towards ESTEC. We must have had a loth to talk about since we managed to miss the stop, however the driver where kind enough to tell us at the next stop. After the small mishap we succeded to find our way to ESTEC where the next surprise awaited us, there are three main roads to ESTEC one for cars, another for bikes and the last for horsed none for pedestrians!
Well at ESTEC Martin Siegel from ESA welcomed us and we where presented to Jason Page who where going to be our course leader. The course started with a one and a half hour long theory pass where we went through the main principles of flight soldering. After that group moved on to the clean room to start the particle exercises. We really did get a loth of good tips and practice for the soldering even if we never will have as good equipment available for the soldering of our experiments. I’ll upload some pictures from the lab.
The secccond night started in the hotels dining hall where Martin Siegel and Koen de Beule joined the group, we continued the night in a bar near the beach where Koen gave us some useful tips on the development of the experiments. Quite to soon it was time for Martin and Koen to abandon the students and we continued on to a night club where we goth some fancy drinks and then on to a verry interesting rock club which where fited in a basement. Interesting enough the first picture which met me on my way in to the club where a picture of Pippi Longstocking.
The last day of the course where in its full length dedicated to practical exercises. I must say that I where impresses over all the different elements we managed to go through during the course length. The day where finished of by a visit to Koens office who kindly enough offered us some components for our experiments. After a dinner at the hotel we headed down to the beach where we took a ice cream and then rounded of the course with some drinks at a mexican restaurant down at the beach.
The next day it was time to head back home. I my self where going to meet up with the parts of the team at Arlanda as soon as i goth there to continue the trip directly to Tierp flight strip for the seccond towing test.

Motors delivered and tested

Last week our motors for the SCALE system was finally delivered. As many of you may know I’ve been rather involved with trying to get our motordriver to work. At first we made a first version which we after some weeks of testing and tuning finally got to work.

Motorstyrningskretsen som den såg ut i version 1

Motordriving v.1

However during the tests we noted that there where plenty of parts in the circuit which could be simplified. So after some final test, that proved that the first version worked  with a similar motor to ours, we decided to make a new version. The new version in its turn where acctually quite delayed mainly becaus a simple mistake when reading the specification of the comparator used in the circuit.

Motordriver v.2

Motordriver v.2

About two weeks ago I finally  made it work, just in time for the delivery of the new motors. So now we’ve tryed the motors both with the new driver, proving that it works, as well as with the older version of it, which we have in two copies enabling us to actually run the motor since it makes use of two motors.

Two motors

The new motor, which we're actually going to use, to the lest and the old one, which has been used for testing to the right

Untangling the rat's nest

Mark writes

Over the past while Nickolay and I have been making the finishing touches on the SMILE board and running some tests and modifying the firmware of the previous LAPLander model. With the SMILE board is just about ready for production, the focus has shifted to my other responsibilities in SQUID, namely the SMILE interface board and the Uniprobe/EFP board.

The completed SMILE board

As Mónica has mentioned previously, the components have been placed and after much deliberation we have settled on the positioning of the external and internal connectors. This is quite critical because it affects the physical structure of the ebox and also the placement of components on the boards, so we have had to play tennis with Jiangwei to decide what is possible and what is not.

Only a few more connections left to route.

Even with this decided, I soon discovered the uniprobe board was incredibly packed and shifted the FPGA and memory up to the SMILE interface board, requiring yet another connector between the two boards. This freed up quite a lot of space although, as you can see, it is still pretty tight. There are over 2500 connections in SQUID and it seems like more then half of them are on the uniprobe board alone. It is an incredible challenge to get everything routed while doing one’s best to stick to good design principles, but it is also a lot of fun. Of course this will need some iteration to get it just right, but we’ll get there.

Time for electronics and software

MONICA writes

Congrats to the mechanic team they are doing a great job in the workshops and impressive CAds.
In electronics we also have advances, finally we defined the number of PCBs we will use, as well as their position inside of the ebox, we spend quite some time defining the interconection between the boards. Once the design of the SCALE system was finished we were allowed to locate the position for connectors to external world and antennas for GPS, Satellite transmitter and Radio beacon.

Boards in the ebox

But definitely Nickolay, Mark and me have spent many hours in the placing of components, some boards are very populated and the routing becomes a bit tight, but we can see the difference in the boards and now they look just amazing!… lets wait for the soldering it will be very funny, fortunately next month Gustav will take a course of soldering in ESTEC (European Space Research and Technology Centre, Noordwijk, The Netherlands) and I will take one in DLR (German Aerospace Center, Oberpfaffenhofen,Germany), although we have been practicing a lot I think the courses will be very good to make it perfect!! ….

PCBs layout

But not everything has been schematics,layouts and soldering…many things are running in parallel, we count now with a new member Linus, he is helping a lot with the camera circuit to control it. Gustav is working with the umbilical connector, doing tests and concluding the design. Also I am preparing tests for the ADC of sphere circuit. And last but not least, the software is coming along with the tests. So, we all have plenty of tasks but when something is working it feels just great!!

Hijacking a GoPro Hero HD videocamera

Some of you may be aware of my lost luggage earlier last month when I was on my way to Stuttgart. Among the things that were lost was the video cam that was supposed to be used for the project. This really happened at the wrong time since we were in the middle of trying to understand how its battery works. So as soon as we understood it was gone we ordered a new camera however the ash cloud came in the middle of everything so we had to sit still and wait for the camera for two more weeks.

After a lot of waiting we finally received the new camera last week. The first thing to do was to continue the work with finding out what the magical third pin of the battery does.

The idea has been to try to “listen” what happens when the camera is turned on, this work has until now been rather unsuccessful. The target is to be able to connect the camera to the rockets internal battery instead of having to use the internal battery of the camera. So if there is someone out there who knows a lot about hijacking batteries please do not hesitate to contact us!