Day 2-4, the masters of card games

And here we thought launch campaign was a lot of work!

Day 2 of the launch campaign was quite slow. We started the day with doing a simple assembly of the experiment to hook it up to the service module where we did a com-test. In practice this means we check that the communication from our experiment through the service module to the ground station works.

The test ran smoothly so we did final assembly where we assembled the experiment with lock tight and predetermined torque. We then made sure everything was connected as per our procedures. Another com-test confirmed that all connections were still good.

This was all done in the morning which meant we had to wait for the bench test the next day. The rest of the day then mostly involved playing cards.

Final assembly

Day 3 was the day for the bench test. The test was set at 13:00 so we set up our ground station and then waited with some card playing. The time for the bench test then changed to 14:00 then 9:00 the next day, One of the other experiments were having trouble so they would have the night to resolve it. So there was no use putting the cards away.

The team playing cards

Day 4, morning meeting, today is the bench test which is set at 10:00, then after lunch, then 14:00. But as I'm  writing this the bench test is actually being set up. So hopefully the test will start soon and we can start setting up for flight simulation which well be done tomorrow.

The experiments being lined up for bench test. Notice how one experiment is still missing.

Launch Campaign - Day 1

During this project we've followed something I'd like to call the SOLAR sine wave. Everything is going perfect until something happens which will make you think "it's all over". The problem then get's solved and your on top of the world again. The launch campaign is no exception apparently.

Yesterday the day started with us dismounting the experiment since we had to change the screws after the bumpy transportation to ESRANGE. That included taking apart the electronics box to see if the micro-SD stored the data as expected. It did, all was well and dandy so we screwed back PCB's into the box. In the meantime we tested out our backup PCB's which had been soldered just last week. For some reason these cards wouldn't let us program the micro controller. We tested the lines on the board but they all seemed fine so we came to the conclusion that it must be the new CPU that is corrupt. Not to fear, we brought a spare and we spent an hour removing the old CPU and soldering on the new one. Of course that did not work either! Well at least we had our flight PCB's functioning, or did we? We switched back to the our old electronics that's been working fine since January but we could not communicate with it from our ground station. Now was the time to panic. After trying everything we took to an old trick, restart the computer. We launched the ground station again and there we go everything is working as expected.

Björn soldering the new micro controller

So what was the problem? It seems the com port we were using on the computer had somehow latched up when trying to program the backup PCB's. Because the compiler didn't get a response from the micro controller it never closed the port. This was later confirmed by reproducing the scenario.

It was still the matter of the backup PCB's though. Why were we unable to program them? We had a lunch to think it over where the payload manager Mikael Inga suggested it might be a different component connected to the programming pins that's causing the problem. The only other component connected to the programming pins was the micro-SD card so we tried removing it worked. We then put the micro-SD back and tried programming again and what do you know that worked as well!

The PCB's that caused all the problem. The PCB with the micro controller is underneath the one displayed.

We're still not quite sure what caused this problem but it could be that some solder in the micro-SD bracket that got removed by taking the card out.

So everything was working great until we once again got the problem that we didn't receive any data to the ground station. After error searching for about two hours we realized we had forgotten to turn the power on.

To brush of an old chestnut, "it's not rocket science"

Final preparation before integration week

 After a long and well deserved Christmas break the team is once again in place and working on the experiment. The experiment is fully functional and is mostly verified. So one might expect that we could lean back and enjoy our wonderful work now, but there's a lot more to be done before we can ship our experiment to Bremen in the end of January.

 

Some of our main points are:

 

• Create the box for shipping the experiment
• Do vibration test with new PCB's
• Prepare the rocket module with covers over the venting holes
• Produce multiple sets of soldering setups for integration week
• Do multiple end to end test with complete system
• Make PCB's flight ready
• Implement temperature monitoring of battery packs during charging
• Implement the sd-backup system

So understandably the team will have to work at full speed for the following two weeks. We are however confident that all the major points will be sorted once it is time to ship everything.

Once the experiment has been sent to Bremen we will send down two team members both named Björn. They are experts on the electrical and software system in SOLAR and could hopefully resolve and issues we could have during integration.
The integration week is pretty much what it sounds like, our experiment will be integrated with the other experiments and the rocket service module to make sure all the interface between different parts of the rocket works as expected.

If we have no major faults in our design the experiment will remain in Bremen before being sent to Oberpfaffenhofen outside Munich. There it will undergo a series of test to verify the flight readiness of our experiment.

So that's what we're working towards right now.
We'll try to get another update out sometime during this week, if not on the blog at least on our facebook page.

Have a nice day :)

 

EAR

So yesterday we had our EAR (Experiment Acceptance Review) and we welcomed Mikael Inga and Alex Kinnaird back to Kiruna! We started off by presenting the updated and improved parts since the IPR and also our last steps before we can send the experiment to Germany for testing. After that we had a demonstration of the actual experiment where we melted six samples and explained the course of events during the flight. We were very happy with both the presentation and demonstration and we hope Mikael and Alex felt the same way :)

Whats left to do for the team right now is to improve every last detail and solve the last minor issues. We will also focus on writing detailed checklists for launch campaign so that we are fully prepared!

We would also like to congratulate the teams on REXUS-11 for the successful launch campaign that took place last week! We are kinda jealous but we hope to join the club in May next year! :D 

ps. check out our team t-shirts!

 The rocket module was tried out and voila, fits like a glove!

 Discussion and time for questions

 Maja and Johanna are admiring the experiment

 The experiment mounted on the bulk head with the candy-looking
power resistors in the electronics box.

 

Today another saturday is spent in the school for the team members living in Kiruna. Todays tasks are to make the last minor adjustments, make the final assembly and perform the final vacuum and thermal tests.

Except that, all preparations have to be made for our EAR that we have at monday morning. We feel that we have got some really positive results since the IPR, hopefully Alex and Mikael will share this opinion.

Here you can see the major part of the experiment while Björn is working on the final assembly before the thermal tests.

The story of Johanna and deadlines

After both exams and halloween celebration we are now working towards our deadline set on the 19th of November when the entire experiment shall be ready for shipping to Germany. The actual shipping will not take place until later but we want to have some time to work on last minute details and refinement.

Our first goal is the SED-submission due on monday the 12th so we figure there will be some late nights and weekend work for the team.

Our work right now is mainally to finish all soldering, PCB-manufacturing and procedure-documentation parallel with several tests. I managed to get a short interview with one of the team members, Johanna!


This is Johanna!

Johanna is working with the mechanics-team. Her work includes FEA-simulations, PCB-manufacturinga and battery insulation. She is studying towards a master in aero space engineering. Her favorite food is moose steak with potatoes and bearnaise sauce and she likes to walk around with a backpack in the forest. Her interests also includes skiing and making snow-angels.

So, Johanna, how is the work coming along?
- There are mostly refinement work left in the mechanics group and we are actually beginning to see the end!

What would you say is the best thing with Project SOLAR?
I would say that the education and team work is the best parts of the project. I learn new things all the time when it comes to project planning and engineering which I think will be a great experience in the  future.

What is the most difficult part of the project?
The communication can be quite a challenge since we have a pretty big team (14 people!)....we are all study at the same time with different schedules so the planning is hard sometimes. I´m impressed that we managed to pull it off during the entire project with meetings, deadlines etc. and there is no stopping us now!
What will you think when YOUR experiment is fired away onboard the sounding rocket?
I will be very happy of course to have actually made it to the end! I will also be very nervous about the outcome of the experiment; will something go wrong? did we forget something? what if this or that happens?
So mostly happy but a little bit nevous!



Is this Johannas life-long dream?

And how is life in the small city of Kiruna?
The surrounding nature is fantastic with the mountains and forest. The view from our school is beatiful now when there is snow on the trees and clear blue sky. The institute of space physics is right next door which is a great benefit when we have technical questions.
But I must say that there could be more people, a warmer climate and a McDonalds....then I would never leave!




Do you have any advice to those who want to start a project?Find a good group of people that you trust and that you can work with through both good and bad times. Make a good and realistic time-plan and what to do if something goes wrong. Have FUN and encourage each other.

Last question, who is your favorite team member in the group?
I would have to say Anneli, since she is so smart, funny, good-looking and a great friend!

Interview done by Anneli

First vibration test

Good evening!

Last week we performed our first vibration test, where we tested our vacuum chamber, the D-SUB holder and our electronics box with the PCB's. Dummy weights were placed on each PCB to simulate the weight of the actual components we will use. This first test was performed to see that our main structures could withstand the expected vibrations from the rocket. We also wanted to ensure that the PCB's with the dummy weights would not crack due to the vibrations (I guess that the electronics group would have gone mad if we broke their real PCB's during the "real" and final vibration test).

The test was done in four steps:

1. We made a sine sweep at 0.25g to search for eigen-frequencies.

2. We made a sinusodial test at Qualification Level i.e. at 4g.

3. We made a random vibration test at Acceptance Level i.e. at 6 grms.

4. We made an additional sine sweep at 0.25 g to compare to the first one to see if the structures had changed (different or modified eigen frequencies).

The results were good and all parts still seems to be alive. However the two graphs from the sine sweeps was not identical, but we found that one of our dummy weights almost was loose, which probably explains the unequality of the graphs.

Here is the experiment mounted on the shaker before the test

We are also happy to give you a video of the sinusodial test (2)

Unfortunately the quality was deteriorated after the transfer from my phone, but hopefully you can enjoy it anyway.

In the beginning the frequencies are low and you can see the vibrations clearly, but at the end the experiment seems to be stationary. This is due to the high frequencies (ca 2000 Hz), so actually it is oscillating extremely fast, or more exactly; ca 2000 times/sec.

Bye!