Raspberry Pi anyone?

Worth keeping an eye on this. The first small (credit card), powerful, low power consumption and cheap(£21) computer which would fit easily in one of our submarines.

Active sonar pond mapping anyone?
Intelligent underwater video - pattern recognition?

It already has an interface board available for motors etc.

Speaks Linux.

Apparently the Farnell site crashed yesterday because of demand but I have registered my interest.

David

I suspect so? You going to phone your sub or is it going to "phone home"?

David

Well my Raspberry Pi has finally aririved after many months.
First impressions are very good. Fast, works straight out of the box and only £24.

This message has of course been posted using it!

The only problem is a crick in the neck from gazing up at very old telly on the wall which I am using as a monitor!

David

I was thinking of getting one but I was told that it won't interface with a dumb ass,!!!!!

Actually if you want a simple guide (and you don't mind swallowing your pride enough to take advice from a teenager!) Have a look at:


https://www.youtube.com/watch?v=28CqDKjtppg

(The last bit of the tutorial covers setting up the initial passwords and the Graphical User Interface in (Debian) Linux - which is the only tricky bit in the setup process.)

David

PS I would say that buying a Pi would be a cheap route for any one wanting a home computer (So that you can browse this Forum) but the £24 is only part of the cost you also need a mouse, keyboard and a router. )(and a TV)

The Raspberry Pi is moving on well. Freely available now and lots of projects associated with it.

I'm afraid that mine is now just hanging off the main television as a media player (For iplayer etc.) but at a moments notice I could start programming (If we aren't watching television!)

To get an idea of what is happening have a look at this:

http://www.themagpi.com/#

Have a read of issue 4 of the free online magazine.You will see an article on attaching an accelerometer (that's not many steps away from level control on a submarine) and also the interesting fact that the next (simpler, cheaper) model of the Raspberry Pi will only draw 200mA (So even better for use in a submarine.) A camera is also coming within the next 3 months.

The current model draws 700mA which is still OK.

David

https://youtu.be/a234ivx7LDE

Now sonar anyone?? Wonderful stuff!

David

Just a quick heads up on my progress with the Pi. (I have had a good play over Christmas because my second Pi arrived just before Christmas. The first one is now permanently hanging off our TV providing iplayer etc.)

I have now got the following bits of hardware plugged in and working:

A 16x2 LCD display. (I see that others are starting to use small 3.5inch screens (Used for car reverse cameras and about £20. May be a better bet.))

A Webcam (VX800).

(At this point I took a phone call from Trevor (Thank you Trevor - good to speak!)

A Velleman P8055 board which plugs into the USB port and provides digital and analogue input and output.

A wifi USB dongle.

Car charger by USB

I run the Pi on a network using remote access from a laptop (using Putty and VNC software. This works well and avoids needing a separate monitor and keyboard.)

I am not quite sure where it is all heading though! What we have is a very, small and cheap (About £25)computer with low power consumption. Has to have some use in submarines!!??

I am still a little bit limited by my lack of know how in Linux and Python language.

Hi David,
Raspberry and all the other flavours of pie I understand completely, and having done as you suggested in your post of Aug 15 I've got some idea of what this collection of electronic components does, though as a seasoned eBay buyer would have thought that a £25 computor could be got by an easier method!! Might be useful if linked to gps device you could rig automatic running around the pond!
Seriously though, as it can be configured as a 3 axis accelerometer that has got to have a use in a boat so I'll be looking into that.
Further to our conversation this morning I have spent some time toying with the pump it's valve and the other solenoids of which I spoke, and have now destroyed the coil as it will not lift against elevated pressures, ah! the smell of scorched laquer.I tried the pump against a gauge but the range was a bit to high for accurate readings and I think that the output is too low for my projected use, I shall rig up a monometer to measure the pump output accurately and also the 'stall' pressure of the coffee machine solenoid and also the pressure that the valve lifts automatically. Further consideration of the various bits of available kit lead me to think about a gas solenoid valve of the type used in automobile gas conversions, they are available cheaply as new, or even cheaper from the local 'scrappy, and they're 12volts.

Trevor

I have just been trying out the new Raspberry Pi camera. (A late birthday present to myself!) It is tiny (about the size of a 2p coin) but has incredible resolution (I think I saw 5 megapixel quoted.) and under £20.

Some initial sample pics of our garden:

https://s1079.photobucket.com/user/david_forrest1/library/Photobucket%20Desktop%20-%20SAMSUNG/Raspberry%20Pi%20Camera

Just the job for underwater camera experiments - I measured  a reasonable 0.25 amps current draw and the whole thing is still the size of a thick credit card.

I know you can get "spy" type cameras but this is a much more flexible approach (programmable for video/still pictures/intervals etc). You could communicate with it from a laptop for downloads etc. by wifi on the surface.

Just the job for someone out there trying out cameras for ROVs, I would have thought.

David

Just been having another look at the Raspberry Pi and bought the latest version - the Raspberry Pi the 3 B and it really flies!

Gives Desktop speeds.

I still can't see any submarine applications but it does now make a very good browser or media streamer ( which can be controlled by Smartphone as a remote) and which could keep you occupied these coming winter nights!

David

Can't a Raspberry Pie do the same things Arduino can do?

salmon wrote:Can't a Raspberry Pie do the same things Arduino can do?

A raspberry pi is much more than an arduino...

arduino has the horse power of an old 1990's era Palm Pilot (16mhz 32 bit cpu, 32kb of shared ram/storage), and has zero capacity off the shelf for anything besides general hack type things (read an input, process data, set an output) it has a boot-loader, but no OS.  it can be expanded to drive simple LCD displays, read SD cards, emulate a keyboard or mouse, but that's about it.

raspberry pi is as powerful as an early 2000s Desktop PC (900mhz quad core 32bit cpu, 1gb ram, 8gb+ storage), and can connect to a standard HDMI LCD display, keyboard and mouse, has ethernet, USB, microSD slot, and is fully capable of running a complete Linux installation.  It also happens to have several general i/o pins, like an arduino.

a raspberry pi would be a good start for a main CPU running an autonomous submarine, controlling as many arduinos as needed to work the parts.

the raspberry pi retails for $35-$50, with some competitors as low as $20...
the arduino (real true arduino) retails for $20-$35, with clones as low as $2.00

last, but not least....

you can install the complete arduino development environment (including libraries) on a raspberry pi...

Yes, so we don't have much on a model sub that needs all that power - video, sonar??

Actually I mentioned the video idea in an earlier post but a Gopro probably does a better job overall.

David