What Mobile chats with Dr Chris Bridges of Surrey Space Centre about the impending launch of the world’s first smartphone-run satellite
On February 25th, the first smartphone-run satellite, STRaND-1, will launch into space, watched closely by its builders, a team of volunteers from the University of Surrey’s Surrey Space Centre (SSC) and commercial spacecraft manufacturer Surrey Satellite Technology Limited (SSTL).
Lead engineer and project manager Dr Chris Bridges talked What Mobile through the plans for the new satellite, which, while initially piloted by an on-board computer, would gradually have control handed over to the Google Nexus One smartphone stowed on board.
For more, see What Mobile’s story here.
First off, why blast a smartphone into space?
Most satellite technology that we want to use has to be very reliable, preferably low cost, low mass and it has to be resilient to a lot of the environment [in space]. The smart phone developments from Google, Apple and other manufacturers almost counter some of the harsh environments here on Earth.
So if someone leaves their smart phone on the dash board of their car in the middle of a Texas summer, you know it’s going to get to 50 degrees easily, which is one of the hottest environments that we’re anticipating it seeing in space. You also then have the ultra cold environment of space so when we’re behind the Earth and we’re not in the sun’s view then it will get very very cold, down to about -20 and of course if you’re in Russia I’m sure there’s absolutely no problem of it getting down to -20.
We want our satellites and our smart phones to be low power and there’s such a good synergy between these things – they’ve now got to a point whereby this consumer driven market is really paving the way of all of our technologies, that it makes sense just to leverage all of this investment and all this technology into our satellites and see if we can try and upgrade them and push the boundaries even further.
Short term, what do you hope to achieve with launching the STRaND-1 satellite? Testing apps, the phone’s accelerometer and the like?
We slowly want to see whether or not the phone can work as an on-board computer – collecting and storing data and processing it so thrusters can be fired or wheels turned in order to spin the satellite- we slowly want to see whether or not the phone can do those functions that we anticipate it can do and how the components react in that environment.
When we test on the ground, all of the tests occur individually and at separate times, but when we’re in space it all happens at the same time, so we’ll hand over control slowly to see what happens and just make sure our software is flexible enough that if we need to upload anything new, then we can.
The main one that we use which is collecting telemetry, or, on a space craft, the house keeping data, and if you’re developing on phones here on the ground it would be all your log files, what’s happening to the hardware, how much memory you are using, what are the sensors doing, all these sorts of things – that will tell us about the satellite essentially.
Here on the ground when we have our mobile phones and use them for games, compasses etc they actually use scientific instruments, accelerometers and as well, the magnetometer which can detect where the Earth’s magnetic field is. That’s very useful on a satellite because then we can know where we’re pointing so if we take a picture we want to make sure it’s not in deep space, but actually pointing at the Earth.
We’ll also be seeing if we can create a random number for when we communicate to the ground, used for instance for encryption, from high energy particles deposited on the phone’s screen, creating a spot. Essentially this energy when deposited can change zeros to ones and ones to zeros, that kind of thing. If you’ve got a big area like a touch screen then if there’s lots of these events happening at once then actually it will create a random environment.
Speaking of tests, what did you do? Bung it in an oven?
We have special chambers since on a space craft you have not just a thermal environment but also a vacuum. We have also done radiation testing, or total ionising dose radiation tests, which tests one of the two ‘big’ phenomena in space, where the physical structure of the components are changed due to ionisation – so for instance if you had transistors it could change perhaps their voltage for switching on and off.
Why Android?
It’s open source – Android is something that’s really accessible, we can get lots of people involved by writing apps; we had a Facebook competition where we essentially said if you had a phone up in space running this operating system, which app would you make, and picked the four best ones.
Have you changed the phone at all?
The phone is pretty much unmodified apart from a few pieces to do with connection. It’s protected through some layers of aluminium and the main satellite body itself. A layer of aluminium actually does wonders.
The operating system hasn’t changed – it’s running Android 2.3.4, so quite an old one, which goes to show you how fast technology moves in comparison to space really – space tends to operate much slower. We started testing on this phone, and every time a new phone comes out, things change and then invalidate all your tests.
We have slimmed down the OS a little, removing things we don’t need to make it more controlled as to what’s running, such as Bluetooth drivers.
What’s this about a screaming app?
What we’re trying to do is detect the vibrations that come out of the app – whenever a speaker is projecting any sound it does vibrate.
It’s also a way to generate outreach; we want people to talk about the tech, we want them to think about what they could do in space. It’s just another way of getting people interested in space, even if it is a little gimmicky.
We’ve played around with it loads but when you’ve got an office and all you can hear is things screaming, we turn it off pretty quick.
Is this the future of satellite technology?
We want to test whether or not these components and these new memory chips and the new sensors and things can be actually really be used on the space craft because typically a flight computer, for instance, can set you back anywhere from $10000 to $25000 pounds, so if I can get a $25 Snapdragon processor that I know works, and then I can build new systems with those devices to much more and at low power, then why not try it?
But someone’s got to take the first risk because the thing about space is there’s this catch 22, whereby unless it’s flown before, we won’t fly it.
What’s next?
I plan to sleep for a few days.
I’m trying to arrange for a webcast of the launch [in India]. As the project manager I should probably be here because I also run the ground station on the uni campus.
I’ve begun doing similar tests with the Xbox Kinect for STRaND-2. One of the things I’ve been studying is how you go about in-orbit inspection.
So if you wanted to inspect, for instance, a satellite that costs $1bn and you wanted to know what’s happening with it or you think something’s damaged, then we’re going to try and come up with a low cost way to view these things and see what’s happening.
The reason we’ve chosen the Kinect is often when you’re in space either you’re going to see the Sun, in which case your sensors are completely blinded with light or you’re in complete pitch blackness so there’s really only about a quarter of the orbit where there’s actually any real usable data where you can physically see the actual sat and the rest of it is either too bright or too dark, so by using Xbox Kinect which uses Lidar, which is essentially laser ranging, then we don’t have to worry about it – we can see in the dark.
Lastly, what’s your poison, smartphone-wise?
I use a Samsung Galaxy S2 – very happy with it.
If you could pick a phone to blast into space, which would it be?
I would probably pick a newer Android with a gyroscope.
Want more RAM with that?
512MB in space terms is huge, so we’re used to using things much much smaller than that. So the technology we fly on sats is a good couple of decades older than what we have on Earth and that’s because they know it works in space so that’s what they launch.
For more, check out the SSC’s Facebook page, which has videos of how the phone fits into the satellite and more.
The specs:
Body: 19×59.8.11,5mm, 130g
Display: 480 x 800 pixels, 3.7 inches
Hardware: Snapdragon 1GHZ Scorpion, 512 MB RAM
OS: Android 2.3.4
Camera: 5MP
