Check out and Possible student sat sensors for in-situ in lower...

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1 Check out and Possible student sat sensors for in-situ in lower... Assoc Profs PhD Jesper A. Larsen & Jens Dalsgaard Nielsen Managers for Student Satellite Programme Aalborg University Denmark QB50/JDN-AAU No. 1 of 22

2 Agenda Discussion of Nature of experiments Some sensor/experiments suggestions for student cubesats to be developed by students QB50/JDN-AAU No. 2 of 22

3 The nature of sensoring Launch will be a great succes!!! Just after - In orbit, separation, ready for start of operation QB50/JDN-AAU No. 3 of 22

4 The nature of sensoring Launch will be a great succes!!! Just after - In orbit, separation, ready for start of operation Then Check out and commision of satellite 1) Does sensor xyz work correct? 2) Does sensor xyz measure something? a)calibration b)... QB50/JDN-AAU No. 4 of 22

5 AAUSAT-II an example A gamma ray burst detector sensor based on a solid CdZnTe (Cadmium Zinc Telluride) crystal. (kindly provided by DTU Space) 10 x 10 x 4 mm, < 5 grams. Detection range from 5 to 300 KeV Very interesting and difficult payload QB50/JDN-AAU No. 5 of 22

6 AAUSAT-II an example A gamma ray burst detector sensor based on a solid CdZnTe (Cadmium Zinc Telluride) crystal. (kindly provided by DTU Space) 10 x 10 x 4 mm, < 5 grams. Detection range from 5 to 300 KeV Very interesting and difficult payload Nature of gamma ray bursts duration from 30 msec to 1000 sec (0.3sec and 20 sec is duration peaks) CGRO mission measured 3000 in 9 years ~= 3 a day hm... QB50/JDN-AAU No. 6 of 22

7 AAUSAT-II gamma ray burst detector - II Q1: when do you know it is working? Q2: when do you know when it is not working? Q3: is no measurements due to broken sensor or just no events? Q3: how to you optimise/adjust the experiment? Q4: when do you go for plan B,C,... The origin of problem Nature of occurence of gamma ray bursts MAY BE VERY DIFFICULT TO SOLVE! QB50/JDN-AAU No. 7 of 22

8 Generalisation Experiments may/shall... have a kind of continous generation of values or at least many events/minute/hour be easy to test and validate in orbit be easy to modify/adjust in orbit be robust in perspective of (mis)adjustments be easy to test in realistic environment be able to calibrate/reconfigure/... from SW before accepting the payload for a mission QB50/JDN-AAU No. 8 of 22

9 Another Concern: Attitude Is correct measurement dependent on attitude of satellite? Is Attitude Determination sufficient? measurement may be synchronised with tumbling case: taking a picture May be difficult to obtain right position rely on right non controlled tumbling of satellite Is Attitude Control a must? Accuracy? Timing Duration of measurements (0.1msec to 10 minuttes?) QB50/JDN-AAU No. 9 of 22

10 Experiment Data Downlink Budget Considerations We do have many very interesting experiments Experiment Data Downlink Budget and 50(fifthy) satellites in orbit Some simple (non correct) math: VKI passes: approx 8 minutes 4-6 times every 24 hour... ~=45 minutes downlink a day when passing Europe Using 43X Mhz amateur radio space band: max 4800/9600 baud for radio link 9600 baud gives 60 kb/min or 2.7MB/day 50 satellites -> 54kB/sat a day!!! QB50/JDN-AAU No. 10 of 22

11 Communication, Genso,... Genso will give more bandwidth An Europe, an American and an Asian branch the Beacon case: Each satellite a 1 sec beacon every minuttes 1 second duration what is left? SO WE HAVE A STARTING POINT FOR A SOLUTION :-) Solutions must be based on a common understanding and communication scheme A very interesting project QB50/JDN-AAU No. 11 of 22

12 Communication and Planning of Operations Payload down link requirements onboard storage,... Onboard pre processing,sorting,... Autonomous swarm organisation and negotiation Next generation protocols downlink basic common command set? plannin of science flight plans Maybe the most important issues to obtain a success? Big and very interesting challenge QB50/JDN-AAU No. 12 of 22

13 Some of the rest Power no nuclear plant onboard only 1-2 W in total weight size camera long lenses hm deployable sensors (like mag field sensors) environment temperature noise, EMC... Sensor (again) counting photons? - hm and maby many many more QB50/JDN-AAU No. 13 of 22

14 ! QB50/JDN-AAU No. 14 of 22

15 What the scientists expect from student space QB50/JDN-AAU No. 15 of 22

16 What the scientists expect from student space QB50/JDN-AAU No. 16 of 22

17 What they may get... (acc to the students) QB50/JDN-AAU No. 17 of 22

18 What they may get... (acc to the students) QB50/JDN-AAU No. 18 of 22

19 Ionosphere Electron Density Measurements using GPS and GALILEO proposed by Per Høeg, Denmark QB50/JDN-AAU No. 19 of 22

20 GPS and GALILEO Receiver Satellite Navigation Systems (GNSS) G GNSS Radio Occultation Method E L E P S a r t h O QB50/JDN-AAU No. 20 of 22

21 GPS and GALILEO Measurements of Ionosphere Electron Density Unique Ionosphere electron density Ne measurements and TEC (Total Electron Content) GPS and GALILEO receiver for monitoring the changes of Ne and TEC during the decent of the satellite through the Ionosphere Data analysis uses the radio occultation technique and tomography that is also able to determine the altitude profiles of Ne Ne profile Global Ne tomography GPS occultations QB50/JDN-AAU No. 21 of 22

22 GPS, Galileo Ionsphere responsible for 40% of position error Ready when Galileo will be in orbit Hot stuff AAUSAT3/NAVIS indicates it is possible to do QB50/JDN-AAU No. 22 of 22

23 AIS Automatic Identification System 162 Mhz communication two channels Feasibility study HW and SDR based system Detection Algorithms Statistics (ground/space comparison) Very hot topic on International Scene Bexus09 proposed by AAUSAT3 - AAU, Denmark QB50/JDN-AAU No. 23 of 22

24 AAUSAT3/NAVIS at Bexus 09 campaign (Esrange) QB50/JDN-AAU No. 24 of 22

25 AAUSAT3/NAVIS How does satellit movement influence on AIS signals doopler, fading, antennas decoding, algorithms, influence from the 300 km below Multiple satellites?! Science! QB50/JDN-AAU No. 25 of 22

26 Albedo and Climate Albedo from earth on moon is an important Climate measurement Today earth based telescopes are under construction for this purpose Some initial tech specs 16 bit pixel resolution 2 degr picture field Onboard processing 10 msec expose time proposed by DMI Danish Metorological Deparment QB50/JDN-AAU No. 26 of 22

27 Sharing of knowledge? Thanks to AAUSAT3/NAVIS students! QB50/JDN-AAU No. 27 of 22