Prisma Satellites - Launch Preparations

The activities at launch are planned over a period of approximately 28 days, of which the last 9 days are allocated to pure rocket activities. The activities can be divided into four blocks:

•	S/C checkout. The satellites are checked for various functions after transport, and finally mated to eachother.
•	Filling activities, comprising mictroprop pressurization, HPGP filling and hydrazine filling.
•	Mating to Dnepr Space Head Module togehter with CNES satellite Picard.
•	Rocket activities. Prisma is now completely in the hands of the launch base personnel, which mounts the SHM to the Dnepr rocket in the silo.

As to the Yasny launch site, SSC has taken strict precautions in regards of the nearby asbestos mine. Experts have been consulted to make thorough measurements and prescribe safety regulations.

Reports:

Simulating Launcher Separation

We had a pretty interesting day in the MCC. We did three different simulations where the spacecraft is just arriving in space after having separated from the Dnepr launcher. When that happens, the spacecraft powers up, and its onboard computer starts a sequence where it unfolds both solar panels. At that point it is tumbling through space, and it begins damping down that tumbling and rotating towards the Sun. This is the sun acquisition, and it is important that this works as it makes sure that the Sun shines on the solar panels, so there is energy. All this is fully automatic, and should be finished before we make our first contact. The first time Prisma flies over Kiruna is around 18.00 and here we hope to see a stable spacecraft which gets power from two deployed solar panels.

But that did not happen today. We deliberately simulated that one of the two panels did not deploy and we would only get half the power. Besides that, the sun acquisition was simulated not to work perfectly, and the spacecraft would have switched to a lot of redundant hardware, including the onboard computer. That makes the first contact much more complicated and we wanted to know if our little team could handle all that pressure. With Niklas calling out the commands, and Nils at the controls we soon had regained control over the spacecraft. So that was a relief to know that this is working as it may just happen next tuesday! (But we hope not).

Tomorrow we try it again, probably then with a simulation where the spacecraft powers up but doesn't notice that it is separated from the launcher. In that situation it will not even switch on its transmitter (that is not allowed when still on the rocket, and that is where the onboard computer thinks it is) or try to catch the Sun. Prisma is designed to survive that, but we on ground have to figure it out and convince it to start talking to us. It is probably the most frightening thing that can happen...

Written by

Ron Noteborn

2010-06-15 / 12:04:24

The Time Line has Started

With the satellites safely in the nose cone of the Dnepr rocket, and our launch team back home in Sweden, one would expect that we have a last week of rest before the mission really starts. Nothing could be less true. In fact the mission has quietly started in the computer laboratories of Swedish Space Corporation in Solna, with the validation of the first experimental campaigns. In order to be sure that our experiments will run as smoothly as possible we have a validation activity for each of them. With our simulators we run the command sequences through and let the simulator tell us what the satellite would do and how it would change its trajectory. If we are happy with that, then there will be green light for the start of such an experiment. This will be an important task of the operations team and the experimenters while we are doing the actual mission operations.

The beginning of the mission will be particularly hectic with all the LEOP, commissioning and Tango separation activities ongoing. The first validation is for the GPS Navigation Calibration, which is a four day campaign in the beginning of august. We need to start early with this in order to have it ready for when we actually need to do the real thing . This validation started yesterday, and for me it marks the beginning of the official timeline! Next week we will be validating the HPGP1 experiment, so you can see we are preparing all we can, and it really feels like we are already in space.

I also want to make use of the opportunity to thank Staffan, Krister, Jonas, Ola, Hans and all the others who brought the satellites safely to Yasny and had it fit for flight on the Dnepr. A good job done, and we are looking forward to bringing the satellite back to Solna, even if it is only in a virtual - telemetry - kind of way.

Written by

Ron Noteborn

2010-06-15 / 12:04:24

Packing, party, and a few words of pride

The last two days have been spent on packing up our equipment, struggling with customs procedures, a nice party with CNES and Kosmotras cheering a successful campaign, and a bit of Yasny nightlife.

Now when the campaign is finalized, I take the opportunity to express a few words of pride.

I am proud of the way we have conducted this launch campaign!

We have carried out an absolutely flawless launch launch campaign. We have done everything we intended to do, exactly as planned, with a very small team, keeping the schedule everyday (well, in fact regained one day lost in the customs) and with a perfect result. We have been able to do so because of good preparations and a fantastic team, highly motivated and extremely skilful. I am proud to be a part of this team!

This is of course not a coincidence. It is only the final of the efforts given by the whole project team of extraordinary engineers, not only at SSC but also at DLR, CNES, DTU and all other partners and subcontractors. We have together done extraordinary things during the past 5 years, from the invention of this fantastic mission involving so much technology development, through the design, manufacturing and testing, up to the moment we are at today. All this to a constrained budget and tight schedule.

I know that the operations team is equally skilful, professional and motivated, and really keen on demonstrating what PRISMA can do in orbit.

I am confident that we look forward to a successful launch and success in orbit.

Staffan_C

A proud project manager, signing off

Written by

Staffan Persson

2010-06-15 / 12:04:24

Encapsulated

And finally - this afternoon, we saw the last sight of Picard and PRISMA. It was quite impressing to see first the Dnepr nose cone lifted on top of platform A with Picard........

Encap_Picard_C

.... and then, the whole nose assembly lifted on to platform B holding PRISMA.

Encapsulation_C

On monday, the whole stack will be put on the transport vehicle and taken out to the silo for the final mounting on the Dnepr rocket in the silo. But this, we will not be able to be a part of, for us is just to pack an go home, waiting for the big moment on June 15, 14:42:16 UTC.

Written by

Staffan Persson

2010-06-15 / 12:04:24

The final touch and Farewell

At 11 today, PRISMA was lifted on to the platform B on the Dnepr Space Head Module.

Integration_C

Hans entered the platform, which also house all rocket electronics, in order to remove the lifting devices, the last Red Tag Items and make ready for flight. And finally give GO for flight.

Final_GO_C

So finally, the small launch team here in Yasny, Hans, Jonas, Krister and myself, could make the team photo below, and say Farewell to our beloved babies Mango and Tango, we hope to hear from them on the afternoon of June 15.

Final_Team_C

PS. If soneone has forgotten anything inside, please say so immediately, we will be encapsulated in the SHM in later today.

Written by

2010-06-15 / 12:04:24

Arming and Red Tags

Today Thursday, the Picard spacecraft was mounted on to the Space Head Module. On PRISMA, the combined operations realy was intense. First, the Russian/Ukrainian team mounted the flight separation pyros on Prisma, then we moved on to the Dnepr adapter, this time permanently.

Adapter2_C

After we were safely secured on the adapter, we have adjusted the separation switches, made a last electrical check to verify that all switches, solar array shortcircuits, transmitter inhibitors and relays are in the correct position for launch. Thereafter, we have armed the satellite, meaning that pyro, transmitter, battery and satety critical propulsion circuits now are connected for flight. (Here is proof that battery arm plug is in and secured)

Batarm_C

Finally, we have removed most of the Red Tag Items, that is all lens covers, sensor covers, thruster protection covers etc which we have had installed for protection purposes. Now, only solar panel covers and lifting devices remains to be removed in order to be ready for flight.

Simulatanesously with the Red Tag Items removal in Yasny, SSC had a presentation on PRISMA in the 4S conference on Madeira. I had looked forward to participate on that conference, and in a way I did - I could give a status presentation via Skype, live from the integration hall. Skype has prooved to be a good tool, we had again a walkthrough with Nils, our thermal engineer, on the last MLI fixes.

Tomorrow is the last operation - lifting onto the Dnepr platform.

A bit beside the point, but anyway - working with a hydrazine filled satellite makes it necessary to have a gasmask at armlength distance. Here, we check that they fit properly.

gasmask_C

Written by

2010-06-15 / 12:04:24

The importance of tape

This morning we rolled out Prisma from the filling hall back to our "old" hall A. We performed a short power-up remotely via a clever EGSE set-up in our checkout room, thereafter we have spent the day taping and patching Multi-Layer Insulation (MLI) on and around e.g. thusters. This activity is very much about tape, and one wonders how the world managed before tape was invented.

MLI_C

As you have already understood by the previous report, Nils Pokrupa, our thermal engineer back home in Sweden, assisted us with advice and inspection via Skype, which turned out to be very useful.

We are now ready for tomorrows final integration on the launch vehicle adapter, and the final check and arming procedure.

We are still dead on schedule!

Written by

Staffan Persson

2010-06-15 / 12:04:24

Inspecting a spacecraft over the internet (!?)

With part of the team down in Yasny, and part of the team here in Stockholm Mission Control, one has to be a bit creative when it comes to logistics. In the days of Odin launch, it was a satellite phone at 100kps giving a few images every second or so... now it is direct video link inspection over the internet from Russia to Sweden using Skype! So today we (here in Stockholm) performed a quick inspection of the Multi Layer Insulation around the thrusters and solar panel pyros prior to stowing the panels in for launch. Next will be to move Mango/Tango on to the launch adaptor, which should happen tomorrow morning.

Here are a few "snapshots" of our Skype checkout:

Video_call_snapshot_3

Hans, Jonas, Krister, Staffan...

Video_call_snapshot_6

... and myself.

Written by

Nils Pokrupa

2010-06-15 / 12:04:24

Fuelling operations finalized

Coming back from a short sightseeing trip in the bigger town Orsk, it is really satisfying to be informed that the Hydrazine fuelling has been performed the last two days exactly as planned. There is now 11 kg of Hydrazine and 22 bar pressure in the tank. The fuelling team, both Thales, Kosmotras and SSC personnel, is celebrating right now with less toxic fluids. Well deserved!

Tomorrow morning, we move the satellite back into hall A and perform a safe power up (remotely controlled for safety reasons) and do some MLI touch-up works before we move to adapter installation on Thursday. From now on, there is continous montoring of Hydrazine fumes around the satellites.

We are still dead on schedule

Written by

Staffan Persson

2010-06-15 / 12:04:24

Operations Team Ready for Commissioning

In Solna we (the operations team) are rehearsing its activities for the mission with the utmost realism. Every 100 minutes our spacecraft simulator starts producing data and the operators in the Mission Control Centre are standing by to send new instructions to the spacecraft and analyse the stream of information coming in.

In the simulations, we are focussing on several complex aspects of the mission. The first week we went through the most cricital activities of the Commissioning. This included checking out parts of the Data Handling System, and getting the spacecraft from its Safe/Sun mode (where it is pointing its solar array to the sun) to the Safe/Celestial mode (where the spacecraft is besides sun pointing also having one side to the Earth).

These simulations were performed while Mango and Tango are still mated to each other. The second week we went through the Target Separation. This takes a full week, and is a complex sequence to perform. We have to make sure that the spacecraft is preprogrammed to be pointing in a specific orientation with respect to the Sun, the Earth, and the orbit itself. At precisely the right moment, we have to fire the pyrotechnic bolts so that Tango becomes free and gets its maiden trip. It will be tumbling in space and without the help from ground, it will have to stabilise itself and obtain sun light on its own solar array. It will be self sufficient for the first time since launch. All this we film with a digital video system, which is ofcourse also to be synchronised in this sequence. To complete this all, we will need to make sure that we do not bump into Tango again so with the help of the two GPS systems we plan carefull manoeuvres to keep it safe.

All this went excellent. Even though it is a simulation, one still gets the same kind of excitement and tension that no doubt the real event will give as well. But this is all still ahead in the future, and the remaining two weeks we focus on experiment execution, and the LEOP activities (which are the command sequences that the spacecraft needs directly after launch).

separation_trajectory_sim

During the mission we produce plots of all kinds of parameters, and the trajectory is one of the most interesting. Above you see the trajectory of Mango relative to Tango, where Tango is at the zero position (at the blue cross). Mango makes one of these ellipses in every orbit, and slowly spirals out. Here we had reached about a kilometer distance after about a day of flight.

Written by

Ron Noteborn

2010-06-15 / 12:04:24

Next: Hydrazine filling

Yesterday was a relatively calm day. The HPGP system pressure was checked and found stable, and the system declared ready for flight. Fuelling equipment is now disconnected and soon packed for home.

The Thales hydrazine filling team is now ready for their task. The hydrazine drum is in the filling room and equipment connected to the satellite. The filling operation es expected to be finished by tomorrow lunch.

Hans and I will take a day off, I expect to write the next report on Tuesday evening.

Written by

Staffan Persson

2010-06-15 / 12:04:24

HPGP is green.

Yesterday, the High Performance Green Propellant (HPGP) was filled by Kjell, Peter and Ola. It became a long day because of a lengthy discussion over a measurement parameter, but the actual filling of the roughly 5 kg HPGP propellant was very undramatic, quick and successful.

Now, we have the first satellite ever filled with green fuel.

HPGPfill_C

I take the opportunity to say a few words about the launch base and the working conditions. Since we live and work in more or less the same building, and the launch base management and staff is very service oriented, it is very easy to create an efficient working environment, with flexible working hours, late shifts if necessary, and what more. This is one important explanation why our campaign can be so short and efficient as it is (and continues to be I hope).

And the food - absolutely excellent!

Dinner_C

Written by

2010-06-15 / 12:04:24

High Pressure

High pressure in Yasny, not only outside. The Nanospace team Tor-Arne and Mattias has just pressurized the Micropropulsion cold gas thruster system. The pressure is now 185 bar in the tank and seems to be stable.

Pressure_C

Earliter today, the different filling equipment were standing side by side - the Microprop equipment to the left, HPGP pressure panel in the middle and the Thales panel for hydrazine to the right.

Fillpanels_C

Tomorrow, filling of the HPGP system starts. We are still dead on schedule!

Written by

Staffan Persson

2010-06-15 / 12:04:24

More pictures from fitcheck

In waiting for being able to report on the pressurization today, here are two more pictures from the fitcheck yesterday. (Courtesy Komotras)

Fitcheck_4

Fitcheck_3_C

Written by

Staffan Persson

2010-06-15 / 12:04:24

Fit check OK, now to fuelling

This afternoon we have performed the fit check to the Dnepr adapter together with the Russian and Ukrainian engineers of the Dnepr rocket systems. This was of course extremely important and slightly nervous to see if everything fits, the "monitoring pressure" was quite high from Russian (and French) side. But as expected, everything clicked nicely into place. An extremely successful day from the standpoint of a mechanical engineer!

Fitcheck_2_C

Preparations for the different fuelling activities have continued. This morning, the Nanospace team, Tor-Arne and Mattias, arrived and started preparing for tomorrows pressurization of the Micropropulsion system. And the Thales filling team has practiced in their "space-suits" for the filling of Hydrazine, notably a dangerous task.

SCAPE_C

Ve are still very much on schedule.

Written by

Staffan Persson

2010-06-15 / 12:04:24

Tango is mated

Early this morning, Hans and Ola doublechecked the separation system, mounted the separation pyro and removed a few "red tag items" in preparation for the important mounting of Tango on Mango. Here, Hans guarantees that all is GO.

Hasse_C

Then we successfully mated the satellites, from now on we are dealing with one spacecraft only, up to the separation event later this summer.

Mating_2_C

We now roll in to Hall B to see that the whole thing fits with the Dnepr adapter and separation system. Read more later today.

Written by

Staffan Persson

2010-06-15 / 12:04:24

Electrical checks finalized

All electrical checks are now finalized after a long day allocated to the FFRF instrument. A new version of the software of the FFRF instrument on MAIN was uploaded and an extensive check and instrument calibration was performed successfully. This means that all onboard systems have been functionally checked and declared ready for flight.

It is a formidable job that has been done in a few intense days, and these are the guys that did it! Krister and Jonas now takes a few well deserved days off.

KSR_JJN_C

We now leave the elecrical testblock and prepare for mechanical integration and filling. Tomorrow, we will mate Tango to Mango, that will be interesting.

Other activities performed today was a propellant transfer of the "Green propellant" to the filling room filling container. Although generally non-hazardous, some protection is suitable, (but compared to the suits used for Hydrazine, still quite comfortable, see after tomorrows hydrazine filling rehearsal)

HPGP_C

The compressor problem from yesterday has been solved - the Kosmotras team admitted that the machine was badly located, and simply moved it to a suitable location and rerouted air and elecrical connections.

We are still dead on schedule! Also the rocket activities are on schedule - this afternoon, the Space Head Module arrived (in a fantastic, typical Russian, military vehicle) to the integration hall after successful End-to-End test with the rocket.

Written by

Staffan Persson

2010-06-15 / 12:04:24

Dress Rehearsal in Solna

Meanwhile the launch team in Yasny are preparing for launch, the operational team are preparing for taking control of the PRISMA satellites after launch vehicle separation. Dress Rehearsal is performed to train the staff and to validate all flight procedures. This week target separation is simulated against the PRISMA simulator with simulated passes. Next week GSOC will join us to participate in the training.

Mission Control Centre

Written by

Anna Carlsson

2010-06-15 / 12:04:24

Yasny is getting crowded

The launch base is now full getting really full of activities. Today, two new teams arrived - two CNES engineers for the FFRF instrument checkout, and a four man team from Thales, responsible for the filling of hydrazine.

The activities on PRISMA today consisted of the final end-to-end test of the propulsion electrical systems (valves, heaters and thermocouples), and a test of the two RF systems of the PRISMA platform - the S-band ground communication link and the 400 MHz intersatellite link. As we have been used to in this campaign, all tests ended with success.

We also squeezed in a short power-up of the FFRF instruments, nominally planned for tomorrow Wednesday. They all seemed to be in good condition which is nice to know for tomorrow, since the FFRF test is at least a twelve hour exercise. Even without any problems tomorrow, it will be a long day.

We also held a planning meeting for the 5 critical days starting Friday, when three propulsion systems are getting filled. Although these activites are planned very carefully, one is always a bit nervous when in this case four teams are sitting together for the first time to plan in detail activities which are both time and safety critical. Considering this, it looks good for the coming days. One problem encountered was however that an air compressor, supplying the SCAPE suits (the "space suits" for hydrazine filling team) with clean breathing air, may be badly located in the clean room and may contaminate the environment for the sensitive satellites, especially Picard with its optical payload. This is something to dig into tomorrow together with Kosmotras base team.

Written by

Staffan Persson

2010-06-15 / 12:04:24

Also Tango "in the clear"

The test activities continue to run smoothly. The Tango AFT was finalized a few hours ago without any problems whatsoever.

Also the HPGP and Hydrazine propulsion systems leak check ended successfully without any suspicions of leaks at any place. All connectors have now been mated and the electrical functions and continuity remains to be checked tomorrow morning. The CNES team Jon and Thomas will join us tomorrow in order to prepare the FFRF system and test equipment for the checkout on Wednesday.

Written by

Staffan Persson

2010-06-15 / 12:04:24

Tango AFT and leak check ongoing

The preparations move quickly forward. This morning, the AFT test block for Tango started. We have just concluded that Tango have started up OK and that the power system looks fine.

In parallel, the propulsion team are starting up the leak check and propulsion systems health check on Mango.

Leak_C

Written by

Staffan Persson

2010-06-15 / 12:04:24

Mango AFT successful

The Abbreviated Functional Check (the AFT) on Mango was continued today, and actually finalized successfully. The AFT procedures test all hardware related functions on all systems on the satellite, nominal aswell as redundant. This means that we are almost back on the nominal schedule after the initial delays with the transport.

Among the many functions tested today was the solar panel deployment, a test with an extra touch of excitement since it is very physical and visible. The successful result was a great relief, especially since it was watched, and cheered, by the whole Picard crew of 15 people or so. See link to video below.

Separation.wmv

In parallel, the propulsion team has unpacked and prepared their equipment such that they are ready fo action tomorrow morning when it is time for the leak check on the HPGP and Hydrazine systems.

Those who have read the activity plan (in the top of this page) and wonder why we have not reported on the fit check to the launcher adapter, should be informed that this has been postponed to the 27/5. This is due to a end-to-end test between the Space Head Module and the rocket (basically an interface check between the rocket and the nosecone with all it's electrical and separation systems). The SHM will be free for fit check and integration activities from the 27th.

The Picard satellite is now unpacked and installed in the clean room. Tomorrow is the power-up of Picard and we sincerely wish the CNES crew good luck.

Picard_C

Written by

Staffan Persson

2010-06-15 / 12:04:24

Satellite checkout successfully started

This morning, the satellites were lifted out from the containers and Mango was made ready for the checkout tests, what we call the AFT, Abbreviated Functional Test. To our big relief, the Mango computer and power system started up OK during the afternoon. It is of course an exciting moment to see that everything have survivied the transport. We are not through yet, the AFT continues another couple of days, but we are happy right now.

AFT_C

Also today, the propulsion guys Kjell and Peter (and Ola who does a bit of everything) have started to prepare the filling support equipment for activities to come early next week. They seem to be on track.

The Picard satellite team from CNES arrived last night, and the satellite transport this morning. They have spent the day unpacking things and setting up their equipment next to us in Hall A (apart from lookiing at PRISMA from the "spectator window")

CNES_C

Soon, we will join the inauguration ceremony here at the base, there will be a moment of hoisting the national flags and celebrating that the campaign has started.

Written by

Staffan Persson

2010-06-15 / 12:04:24

A good first day

We now close down for the day.
We have been quite efficient in unpacking the EGSE and prepared for test tomorrow. The satellites are partly unpacked and we have verified that the shock and temperature environment during transport was within specifications. However, the satellites are still partly in the containers - we don't want to detach and lift them without having Ola, our mechanical handling guy, here. He was unfortunately held up by a bad flight connection yesterday.

Nevtheless, we are in a good position for tomorrow and we think that we have regained say half of the lost day in the customs. The propulsion team (Kjell and Peter) also arrives tonight one day after schedule. I hope that they also can catch up, they have a few days until they are on the critical path.

Written by

Staffan Persson

2010-06-15 / 12:04:24

Installing satellites in cleanroom

We have now unpacked most of the equipment an are installing EGSE and satellites in the cleanroom. We are still a very limited crew, only Jonas, Krister and myself since three guys missed the flight from Moscow yesterday, so we have a lot to do.
I just checked the shock recorder of Mango. It looks like it had a nice ride despite the road from Orsk. In fact the road transport did not show at all in the event log (trig level set to 2g). Good marks for the trailer suspension.

Krister unpacking
Getting the cleanroom in order

Shock recorder
One shock event

Written by

Staffan Persson

2010-06-15 / 12:04:24