Hej everyone!! 😀
Most of the team is now back from their well deserved Christmas break! We discovered with joy our beautiful custom module (which must have given a lot of work to Moraba!) and all the work our dear Romanian fellow had accomplished (while we had abandoned him without any remorse in Stockholm).
Well…not everyone is back…we lost a few people over Christmas (I mean they went home, for their studies or to start their master thesis). We are especially going to miss our electronics wizard Jorge who had been working on ISAAC since the very beginning!
However, we can now also count on our new fellows from the SCRAP team, the next KTH Rexus team. And we don’t refuse any extra-help, we are now on the home stretch: delivery of the experiment is in 13 days! (which is getting our team leader a little bit more nervous everyday). We are waiting for the delivery of parts, manufacturing everyday to be on time. After the delivery, Georg, Ruslan and I will be heading to Bremen for the Integration Week.
It’s quite rewarding to finally see the experiment “grow” a little bit more everyday, I can’t wait to test the ejection system! So far, all the parts are fitting well together (the hours spent on CADing were not useless). Here are some pictures of the latest parts:
Hooks of the retention system
Hatch and pusher plates – the red parts are the hatch stop for the hook and the ejection spring connection, these were 3D-printed, but I started to manufacture them this morning with Lucas (SCRAP team)
D-sub bracket sent by Moraba – this is also custom made for our module, usually there is space for 3 connectors
After hours of CAD-ing, many analyses and drawings, it is finally time to manufacture!
I started with the balconies, 12 L-shaped aluminium parts linking the supporting grids to the vertical connectors. At first sight, this seemed as an easy part, L-shaped, three countersunk screw holes. However, I didn’t really have any experience in manufacturing so I first had to learn how to use the milling machine, drill and saw (which was fun :D).
We started by selecting the raw material, a long L-shaped 4 mm thickness aluminium bar. We cut it into 24 rough parts ( yeah, we knew we were going to fail some of them). With the milling machine, we adjusted the dimensions of the balconies and finally used a drill to realize the countersunk screws. Meanwhile we had received the vertical connectors (perfect timing!). These parts, which are quite sophisticated, were ordered. After several hours spent in the workshop with my pleasant manufacturing buddy Vlad, we were finally done and the balconies were screwed to their connectors ( and they fitted :D)
Connector & balconies
After the balconies, I started to work on the steel plates used to restrain the ejection cable. As the cable is also made of steel, it is better to have a steel-to-steel connection; otherwise the cable would just dig into the aluminium. Cutting these plates took us more time,steel is harder than aluminium… With the help of the engineers from the workshop, we set up a horizontal saw to cut the steel plates. Next week, I will mill them and add the screw holes.
That’s all for today! One more thing though: good luck to the new KTH team heading to ESTEC next week for the REXUS/BEXUS selection workshop! 😀
No spoilers, we are not telling you what the new REXUS project is about! Since the first project, LAPLander, the KTH team have faced crazier and crazier challenges, involving FFUs more or less big and giving some cold sweats to a few MORABA engineers.
So here we are again, the REXUS call for proposal is opened until October 21st. On thursday 26, we have been invited to present the REXUS/BEXUS programme to the new Aerospace master students. Team members of SQUID, RAIN, MUSCAT and, of course ISAAC, will be gathered for this presentation. We hope to convince a lot of new students to join this amazing programme, reminding them it might be some work but it’s also about fun, travelling and meeting space enthusiasts from all over Europe!
We will update pictures just after the presentation!
(and if you are a KTH student and want to join the new team, you have until October 6 to contact us)
After almost 9 months of design, we are finally adding the finishing touches on our ejection system (okay we are running a little bit late..)!
One of the last part we designed was the camera mounting. To analyse the ejection (and well also because we don’t want to miss the view 😉 ), we have installed a GoPro Hero3 behind the upper FFU. Here is a picture of the camera mounting which will protect the camera during launch:
Another topic which has kept us busy for a while is the Hot Gas protection. After the ejection of the two FFUs, our RMU will have two openings. During re-entry, Hot Gas will rush into the module. That’s why we need to isolate our module from the other experiments to protect them (and avoid some troubles on ground). We also need a tunnel for the electrical cables going from the experiments above us to the service system module. One of our major issue is space. Our module is really crowded… To win some (space), we designed a tunnel in two parts with an angle as you can see on the following picture:
And that’s enough mechanical updates for today!
About outreach, we are starting to look for the next KTH REXUS team. The call for proposals to fly on the REXUS 17/18 rockets is opened until October 21st! We will present the REXUS/BEXUS programme to the new master students of KTH on September 26st.
Last but not least, we are soon going to order stickers! Can’t wait to put it on my laptop 😀
It has been a while since our last post… This end of the year was quite busy: exams had arrived (rough time for students) and we also had to prepare our Critical Design Review(CDR). Since, it is now summer time, we will post an article a week until September.
As you may have seen on our facebook page, three weeks ago we were back at DLR, near Munich to present the final design of our experiment (CDR). The experts were quite pleased with our presentation and the work we had accomplished since the Preliminary Design Review. We returned to Stockholm with useful comments and a good feeling that our experiment design was going the right way. Meanwhile, Jorge, our electrical engineer had the chance to stay a few more days to attend a soldering course!
It is now mid-July – and the French National day by the way ! 😉 – some members of the team are still working on ISAAC in Stockholm while the rest of the team has scattered around Europe (but no worries, our time will come!).
All I can say about the ejection system is that it is looking quite good, we almost have the final design. We are currently running stress analyses on the critical parts (the hooks for instance) to verify that they will tolerate the launch loads (which is to say 30 g in the vertical direction).
Here is a view of the ejection system:
While the analyses are being performed, I also have to make drawings of the parts. When these two tasks are over, it will finally be time for ordering, manufacturing and later testing. I hope to show you pictures of the RMU parts soon !
Great gift from the REXUS organisation: we are going to have our own custom module! A what? A unique REXUS cylinder module made just for us. Why so excited? The design of our modified module: too weak to support the launch loads (omg a detail), two large openings (250 mm width x 85 mm height) was one of the main issues of our experiment…
We first considered carbon-fiber-reinforced walls as reinforcements. However, the behaviour of the connection of these walls with an aluminium support was too unpredictable and thus too risky. Our second proposition involved four aluminium plates on each side of the RMU openings (I already presented this design in one of my previous blog article).
The new approach chosen is to increase the thickness of the module, as the previous KTH team MUSCAT did. (The standard thickness of the module is 4 mm.)
Meanwhile, the ejection system design is quite a struggle (as usual), but we are keeping hope, working a lot, enjoying our nerd spring, dreaming about the day when it will be our turn to launch from Kiruna!
For now, we wish good luck from Stockholm to our “big brothers”, the MUSCAT team, flying in two days on REXUS 13!
This is also the occasion for a huge thanks to our supervisor Gunnar Tibert for his help with the analysis of the RMU module!
Small french touch to end this article, because we also find ways to enjoy our time in front of NX, great sound from Daft Punk: Get lucky – Daft Punk ft Pharrell Williams 😉
Back to CAD,
News from the RMU mechanical team can actually be condensed in this article title, CAD – Computer aided designed – of the ejection system is still far from the expected CDR result… However, the RMU team (well okay that used to be only me…) captured an additional member: Antoine, a French student doing his master thesis at KTH.
Brace yourself the team is now 100% French and I know at least one ESA expert that would make a few jokes about it…
Back to business: Last week focus was on the deflection of the aluminium beams supporting the FFU. The maximum weight of one FFU is 2kg. The FFU is in contact with three beams, including two below. It is especially these two last beams that interested us since they are submitted to a 30g x 2 kg = 588.6 N force in the vertical direction due to launch loads. The aim of this analysis was to determine the minimum allowable deflection hence thickness of these supporting beams. Answer is: the two lower beams should be at least 15mm height…Knowing this, we can now design the final version of the vertical support which will maintain the FFU before the ejection.
Don’t panic, this is only a focus on the support maintaining the FFU in the vertical direction with three beams, the current state of the ejection system is more elaborated!
Hope to post more pictures soon! Back to CAD!