Astropi specifiactions

[julien.launay]

Hello,

Could you tell me the precise conditions of use of the astropi.
Is it always fixed? Is that astronauts can be removed to carry out an experiment?
Do astronauts can use astropi when the proposed experiment. What time do they have to carry out the proposed experiments.
What is the very exact positioning in the astropi iss. Ref for the compass, accelerometers, gyro. Reference 3 specific axes.
What is the duration of a maximum experiences?
Which differences between the 2 raspberry? do they have the same sensors?
could you confirm me that the cameras are out of work, we can't use them? If we can used them, could you tell me where are they pointing to?

Thank you for your answers.
Your sincerely

Julien Launay

[bensimmo]

You might need to look at the ESA website and see if they know where they will be.
I would assume in the same places as they where when the original UK competition was run and the same restrictions. Have a look back on the details and outcomes for that.

There are cameras on each and I've seen no mention of them being out of use.
The difference between the AsteoPi is one has the NoIR camera and the other the standard camera. Just remember these are the older V1 cameras.

At this stage it's just a proposed outline for and idea for a project and I'm sure specifics may be given later.

Maybe these and the pictures will help
https://www.raspberrypi.org/learning/as ... -analysis/
This gives location and a map among lots of other things

Specs before they went up iirc
https://www.raspberrypi.org/blog/astro-pi-tech-specs/

[Davespice]

Bonjour Julien, thanks for your questions. I'll try to take each one in turn below.

Is it always fixed? Is that astronauts can be removed to carry out an experiment?

There is one Astro Pi hard-mounted on a multi-use bracket in the Columbus module. A second one was mounted onto a hatch window in Node 2 but is now in storage. The crew can remove it from the bracket but constraints on crew time would mean that this activity would depend on them doing it in their free time which cannot be guaranteed.
https://www.flickr.com/photos/timpeake/ ... 3026581031

Do astronauts can use astropi when the proposed experiment. What time do they have to carry out the proposed experiments.

The Astro Pi will mainly be doing automated processing without the involvement of the crew. The crew time we do have allocated for Astro Pi is mainly for deployment and stowage activities. Despite this we have found the crew to be highly engaged in Astro Pi activities and willing to interact with student experiments, but this would depend on the personal choices of the crew member.

What is the very exact positioning in the astropi iss. Ref for the compass, accelerometers, gyro. Reference 3 specific axes.

It lives in the starboard end-code of the Columbus module. The exact position can be seen in this picture: https://www.flickr.com/photos/timpeake/25225355364/ (look closely in front of Tim's nose). This resource explains the IMU sensor and which axes are which: https://www.raspberrypi.org/learning/as ... ovement.md

What is the duration of a maximum experiences?

In previous missions we have let student code run for 7 days at a time, however this time around there will be code from every ESA member country. So I believe you will get one full day of run time in space so we can get through more programs in the time we have allocated.

Which differences between the 2 raspberry? do they have the same sensors?

The sensors are not part of the Raspberry Pi computer, they reside on the Sense HAT which is an add on board. The Sense HATs on ground are identical to the ones in space. However the Raspberry Pi in space is a B+ so it may be that code you write on a Pi 2 or 3 might run slower on a B+. For a closer look at Raspberry Pi products go here: https://www.raspberrypi.org/products/

could you confirm me that the cameras are out of work, we can't use them? If we can used them, could you tell me where are they pointing to?

No the cameras are working fine, they can be used for pictures and videos. However we have found that experiments for detecting radiation have not been successful because of the thick aluminium case. The camera points out of the bottom of the unit, it's located in the middle of the heat sink on the base. So usually the Astro Pi in Columbus will have it's camera pointing at the bulkhead.

I suggest you have a look at some of the previous science results here: https://astro-pi.org/competition/science-results/
There are links to the code they used and the data they received back from the ISS.

There is a slightly out of date FAQ on the Astro Pi website here too which may answer some of your other questions: https://astro-pi.org/coding-challenges/challenge-faqs/

I hope this helps.
Dave

[julien.launay]

Hello,

Thank you for your answers.
I note that on the photo which shows the installation of the astropi, it is not perfectly parallel to a reference position of the ISS wall.
Would it be possible to ask the crew to properly position the module by setting parallel to a reference axis of the ISS.
It would take the exact position with respect to an axis of the ISS

I noticed that there were several different functions to read the temperature or humidity, pressure.
sense.get_temperature_from_humidity ()
sense.get_humidity ()
I imagine that these two functions do not reference the same sensor?

What is the maximum file size that can be saved on astropi. Could you tell me where it is possible to save a file? its tree? format of the file name?

your sincerely.

Julien Launay

[julien.launay]

Hello,

Can you tell me why they choose the altitude of 400km for the ISS? no too far from the earth?

How long last a reboost?

thanks.

Your sincerely.

Julien Launay

[bensimmo]

Have a look at the datalogging with the SenseHAT a hy are now called.
It wilshow you a way to log from all he sensors.

The two temperature sensors are both integrated with their respective chip, see the detailed chip specs.
Be aware you may also want to have a look at the data linked to show how they vary and they are a measure of the two in an aluminium box above a pi processor. and LEDs.

I guess you can ask them to do anything, no idea if they would do it. I guess it's about time and practicality.
Try asking the ESA about that sort of hands on approach.

[bensimmo]

Hello,

Can you tell me why they choose the altitude of 400km for the ISS? no too far from the earth?

How long last a reboost?

thanks.

Your sincerely.

Julien Launay

Edit/ post before seemed to have been mangled ..

For a reboost have a look at the log files linked to (first link in my first post) and try work it out.
It depends on what is attached at the time I guess.
http://www.astro-pi.org

400km is an approx measurement, at the moment I think it's near the lowest it has been. It really needs the Shuttle to get it back up high again iirc. But ask or look on the ESA website before that, or go learn a bit about the ISS itself.

But it'll be something like.
The mass of it, it's angular velocity, not falling down too quick, can talk to it and do science stuff and get rockets up and down from there. No doubt £₱€$¥ are involved to. Keeps out of the way a shards of stuff more easily too.

[jamesh]

Hello,

Can you tell me why they choose the altitude of 400km for the ISS? no too far from the earth?

How long last a reboost?

thanks.

Your sincerely.

Julien Launay

There are generic ISS questions, not RaspberryPi related - I suggest trying the NASA website and/or ESA, and/or Wikipedia for information like that as you are more likely to find the information you need.