Raspberry Pi

[kruland]

Hey Kevin,

Did you see that Android 4.0 has been ported to Raspberry pi? Maybe you can have a rocket which runs OpenRocket! BTW - where did you get yours?

Kevin

[ClayD]

i wonder if this would run the ALTOS program for the telemetrum?

[rockets4kids]

i wonder if this would run the ALTOS program for the telemetrum?

The Telemetrum uses an 8051 MCU core which is rather old and simple and you could probably run it under an 8051 emulator on the Pi, but that is rather absurd...

[ClayD]

I mean running altos.... which is the interface program... basicly acting as the ground station in-lieu of the laptop.

[rockets4kids]

I mean running altos.... which is the interface program... basicly acting as the ground station in-lieu of the laptop.

The ground station software is written in Java, so I don't see any reason why that wouldn't run on the Pi. But then you are left adding a keyboard, mouse, display, and power source, and putting it all together in a case. It would be a whole lot easier to just use a laptop or tablet. Again, you can do it, but it still doesn't make a whole lot of sense.

[ClayD]

yes, making your own ground station is an extra step. i am not that familiar to know if the JRE would work with the linux version...

its a really cool toy tho!

[DM1975]

Man I am "tech-dumb". I wish I knew what all you guys were jibba jabberin about.

[Nerull]

Why? It seems like a rather logical argument to me. This is an excellent example of the KISS principle. To me, using the Pi for any typical rocketry applications would be like replacing the plastic flap governer on a two stroke Briggs and Stratton with a PLC setup.

Failure resistance is about hardware resilience and redundancy. Striving for small size, low power and light weight can make hardware more failure prone, not less.

The Pi is not suitable for a flight computer, but there are a lot more possibilities than that. Only two people seem to be stuck in the flight-computer only mindset, and they seem to be the two people busy declaring nothing could possibly work.

[troj]

Did you see that Android 4.0 has been ported to Raspberry pi? Maybe you can have a rocket which runs OpenRocket! BTW - where did you get yours?

Interesting! I may have to give that a try on another flash drive. I expect a touch interface transferred to a mouse/keyboard will be an epic fail (Windows 8), though.

Mine came from Element 14; it actually came 3 weeks earlier than they last said it would.

I ordered mine back in April; lead times are now about 5 weeks, from what I understand.

-Kevin

[RadManCF]

The Pi is not suitable for a flight computer, but there are a lot more possibilities than that. Only two people seem to be stuck in the flight-computer only mindset, and they seem to be the two people busy declaring nothing could possibly work.

I agree fully, there's a reason I said typical rocketry applications. I focused on the pi's defficiencies in those areas simply because they are perhaps the first things one thinks of when you say electronic payload. That said, I might consider using a pi for something atypical, if it were beyond the abilities of arduino. Like a windshear detection device. Or maybe a full blown weather station.

[CarVac]

Hah, then you could control not only airstarting, but groundstarting: it ignites once the wind dies down for five seconds, and cancels if the wind picks back up.

[RadManCF]

Hah, then you could control not only airstarting, but groundstarting: it ignites once the wind dies down for five seconds, and cancels if the wind picks back up.

I'd think it would be more cost effective to put that control logic in the launch pad. I say the pad, not the controler, because due to minimum personnel distances, conditions could be different at each. I don't know how this would work with the countdown requirement, though.

[CarVac]

You have it start the countdown as soon as the wind dies, and if the wind picks back up it would stop automatically.

[RadManCF]

You have it start the countdown as soon as the wind dies, and if the wind picks back up it would stop automatically.

I guess that would work. It could be made backward compatible with existing launch control systems- use the firing current to tell the pi to initiate countdown when wind allows. Alternately, a new launch control system could be built around a pi.
I've kicked around ideas for an "Integrated Range Control System" that would combine launch control, communications, and fire suppression into a centrally controled modular system. The pi could be very well suited to this... and probably one of the cheapest components...

[Timothy Allen]

Have fun with your computer. You could use it to control servos for flight stability or to direct you landing. You could control your ejection charges or to monitor that your ejection charges went off and to fire a secondary. You could buy some antennas and try to build a GPS. You could flash LEDs, or play music over a speaker. Whatever you do don't be practical, practical is boring and usually doesn't involve rocket fuel.

[sylvie369]

You have it start the countdown as soon as the wind dies, and if the wind picks back up it would stop automatically.

So in the future we'll hear the LCO say "5-4-3-2-1 ok, computer, you have my permission to launch when ready".

[ClayD]

So in the future we'll hear the LCO say "5-4-3-2-1 ok, computer, you have my permission to launch when ready".

It would have to be passive imo.... where the LCO would have to have the launch button held the entire time, and allow the computer to launch, but stiffle the computer launching if the button is not held down. *this would be required to comply with the safetycodes launch system criteria...*

That way the LCO still has no-go control in the even something changes like a car on the highway, plane, or person not doing what they are suposed to be doing.....

[RandyM]

Interesting! I may have to give that a try on another flash drive. I expect a touch interface transferred to a mouse/keyboard will be an epic fail (Windows 8), though.

Mine came from Element 14; it actually came 3 weeks earlier than they last said it would.

I ordered mine back in April; lead times are now about 5 weeks, from what I understand.

-Kevin

I ordered mine on July 27th and go it on August 8th. Looks like they are caught up for now. Not sure what I'm going to do with it, but I'm a geek. What can I say. I'm sure at some point, it will fly in a rocket of mine.

It will only be there to collect data, just not sure what data it will collect yet.

[GuySmith]

Got mine yesterday evening. Up and running, next is to install openoffice, java and openrocket ...

[troj]

Got mine yesterday evening. Up and running, next is to install openoffice, java and openrocket ...

What distro are you running? As far as I know, all the Java installs use soft float, which is slow on the Pi. Oracle says they're working on a hard float install, which will perform a lot better, at which point OpenRocket and such will perform better.

-Kevin

[GuySmith]

I am using the soft float. I had heard it was slow, but wanted to give it a shot to see if it was at least useable.

[troj]

I am using the soft float. I had heard it was slow, but wanted to give it a shot to see if it was at least useable.

Let me know how it works, after you try it. I've not yet installed it on mine.

-Kevin

[troj]

BTW, I also ordered a Gertboard for mine.

-Kevin

[GuySmith]

Nice! For COTS, it would be hard to beat. Bit of overkill for me though.

[GuySmith]

Well, after a few mis-steps I now have the system running Openoffice, java AND Openrocket. Openoffice runs very well for my tastes, not blazing fast but not irritatingly slow either. Openrocket does run fairly slow - I would not use it in this envirnment as my primary development platform, however, I find it quite effective for field operations to check out changes made while prepping for flight. All in all I am happy with the results so far.

[kruland]

GuySmith,

What parts of OpenRocket appear slow? Is it the initial startup, execution of simulations, or general UI responsiveness?

Kevin

[GuySmith]

Kevin,

The initial startup and execution of the simulations are a little slow, the UI responses were fine. I haven't tried the plots yet - I will get to those tonight. The startup and execution is only objectionable when compared to today's instant gratification culture with multi-GB memory and multi-core multi-GHz CPUs. Coming from an era where computers only existed in large businesses and colleges, it is more than acceptable to me. I just wanted people to not expect blazing performance from this platform. The fact that it runs at all impresses me the most.

Guy

[kruland]

Kevin,

The initial startup and execution of the simulations are a little slow, the UI responses were fine. I haven't tried the plots yet - I will get to those tonight. The startup and execution is only objectionable when compared to today's instant gratification culture with multi-GB memory and multi-core multi-GHz CPUs. Coming from an era where computers only existed in large businesses and colleges, it is more than acceptable to me. I just wanted people to not expect blazing performance from this platform. The fact that it runs at all impresses me the most.

Guy

Guy, It's probably more related to floating point performance than memory.

Kevin

[GuySmith]

Kevin,

I agree. Once the hard-float versions of Openoffice and Java are released, I will re-image the sdcard, but this works passably well for the mean time.

Guy

[mdoering]

I had the exact same ideas for when I get one...

I see this having more of a "smart rocket" system, as in one that monitors it's stability in flight, and can adjust accordingly. Also, one that can look with a camera while under decent and steer itself away from trees....

With this kind of computing power, the possibilities are endless. Overkill for "normal" applications, but who wants to be normal?

I have a feeling that wouldn't be legal... I think at that point the term "guided missile" is more appropriate than "amateur rocket"

Being a computer geek, I'd love to throw a Raspberry Pi in a rocket and have it do things... but then again, my sprinklers run on shell scripts and relays with a custom HTML5 GUI (and native iOS app)...