A question of lego..

[dryfter]

Does anyone know what the current status of Lego robotics and interfacing with Linux is like?
Let me explain..

My house has suffered a few power or gas failures recently. They have been entirely our fault, due to the pre-pay meter running out.
burritob suggested we should hook a webcam up and keep track of the credit that way. Hell, we might even be able to do OCR on it. As I have spare linux-compatible webcams, this would be fine, except that one of the meters needs you to press a button in order to display remaining credit.

So, I'm wondering what state Lego Robotics stuff is like these days. It all came along too late after my childhood for me to have played with it, but any excuse to get some out again is good.

Does anyone know if you can directly control stuff though? Eg. I want to write a program, that will run on Linux, that can give the Lego commands to turn motors and stuff, so I could put the webcam on a sliding rail that moves between the two meters, and has another motor that extends a rod to push the "display credit" button.
Is that sort of thing possible? I think I've seen Mindstorms demos that looked like it was all standalone - eg. you program it once, but then it just runs off and executes the program, rather than continues to receive input from the PC. I would need to have interaction with the PC though, in order to take the webcam shot at the correct time.

Any suggestions on other technology to use?

Comments

[vatine]

I have successfully used kermit to talk to a Lego Mindstorm PCX.

[wintrmute.livejournal.com]

What kind of stuff can you actually do with a Lego Mindstorm controller?
I gather they have support for various lego-brick sensors and actuators, but do they have any data I/O ports? (ie. to signal to the PC that "I'm in place, take picture now", or to receive a "picture taken, please move to position #2 now" message)

I guess it might be possible to hack something up with a parallel port pretending to be a light-brick, and then have the mindstorm controller blink messages across at 1bps, but that seems a bit of a kludge.

[vatine]

They've got a serial port to the PC. The "standard" Mindstorm load is pretty boring, but there's a Forth you can snag. IIRC, I've also had a scheme REPL on the PCX, interacting via the (IR) serial port.

Can't say I recall any of the specs, I'm afraid, been a while since I poked at it last.

[miss_squiddy]

I *think* there's a new technix set with a computer interface. You should be able to have a look at that on the lego website. There's even a build program on there so you can work out which bits you'll need and order them as a kit :)

It may also be worth checking out Make magazine and seeing if there's anything in their online archives.

[alexmc.livejournal.com]

There is a whole new wave of Lego Mindstorms-like products being launched soon.

I think this is probably a technical solution for a human problem - just feed your meter regularly once a week.

[wintrmute.livejournal.com]

this is probably a technical solution for a human problem.

Oh, absolutely! :)

[maelorin]

we used to put a coin in the slot everytime we passed through the front door. (thsi was back in the 70s when we lived in the uk for a couple of years)

coincidentally, the only thing never stolen on our estate were 50p coins. you could have a bucket with 1000 of them, and you're place could be stripped clean, but the coins would be left to keep you warm.

as a fellow techgeek, i applaud your interest in a technologicla solution - thing is - you'd still have to rememebr ot feed the 'bot so it had somehtign to feed the meter with.

is there anywhere in that godforsaken place that has moved on from the 70s yet?

[wintrmute.livejournal.com]

I believe there are places that have moved on to the 21st century.. however you need a million pounds just to be able to move in, let alone live there.

[maelorin]

ah. so ingerland hasn't changed much. great.

hope your new job is good/fun/interesting/doesn't-make-you-want-to-scream :)

i'mn enjoying part-time academicness ... being a technerd at a tech-oriented uni is fun.

[wintrmute.livejournal.com]

the new job (started today) is good so far.
They have some new projects that I'm going to be working on that are really quite cool, and more interesting than I was expecting, actually!

[maelorin]

yay!

[arriving at work shouldn't be worse than the trip to get there.]

i'm enjoying my work and figure everyone else should too :)

[martling.livejournal.com]

Works fine. We did this with it, which is actually a pretty similar project. We used leJOS on the RCX brick, other options include brickOS or TinyVM.

Communications go via the IR tower. I seem to recall some fiddling to get the Linux driver for the USB tower to work, but the serial ones were fine and the USB driver has probably been sorted now.

[wintrmute.livejournal.com]

Thanks - and I'm very impressed at the shopping robots!

[karohemd.livejournal.com]

That has to be the most geekish post I've read in a while. At least the best one that has an actual everyday use. :o)

[barbedwirekiss.livejournal.com]

Any suggestions on other technology to use?

Yeah, a clock and a finger.

Works like this:

- Clock buzzes to wake you up in the morning.
- You get up
- You do normal morning type stuff
- You then use 'finger' to push button and read meter
- If meter reading too low, get extra credit
- Repeat

Simple, effective, already used a gazillion times over and requires no extra kit or preocedural debugging! :)

Good luck with "the project" though. It'd be interesting to see the end result.

[barbedwirekiss.livejournal.com]

s/preocedural/procedural/

*doh!*

[wintrmute.livejournal.com]

yes, but I get geek points if I can have an MRTG graph showing the power usage of the house. (Which might be possible via OCR of the webcam image of the credit remaining..)

[voofy.livejournal.com]

I've got a better one,
call the electricity company and say you'd like the prepay meter taken out and replaced with a normal meter that you get bills for quarterly, and pay by direct debit.

[wintrmute.livejournal.com]

last time we tried that one, the landlord nixed it.

[maelorin]

of *course* they did.

they don't have to live there.

[chiselwright.livejournal.com]

This really isn't Toby's world though is it ... something more like:

- stay up until after 2am, geeking or gaming
- clock buzzes to wake Toby up in the morning
- clock buzzes a bit more
- some strange buzzing noise, what on earth is it?
- sleep a while longer, with this strange dream about lots of buzzing bees
- wake up mid-morning, send an SMS to say you're going to be late for work
- turn of annoying buzzing alarm clock
- geek a bit
- head out to work in a rush

No time for that whole meter stuff ;-)

Speaking of work, hope the new job goes well for you next week Mr C. It's been a pleasure sitting next to you in the orifice all this time.

[feanelwa.livejournal.com]

A whiteboard with a pen on which you can write "It is X's turn to buy more electricity!"

[maelorin]

ooh! lo-tech.

but ... have you seen what geeks do with whiteboards? code, schematics, proposed designs for the robots we *must* have ...

[feanelwa.livejournal.com]

Yes, I am one. You need to write the rest of the message in permanent pen, and only the name in temporary, so it doesn't get rubbed off.

[maelorin]

and have the board in the right location :)

[poggs.livejournal.com]

You mean you don't have an SNMP-manageable meter?

[wintrmute.livejournal.com]

That would be far too helpful of the companies to provide..

[cybermuppet.livejournal.com]

Wouldn't it be easier to get the meters changed? Afterall, pre-pay meters are for poor people :/

[wintrmute.livejournal.com]

We asked about this when we first moved in, and our landlord firmly said we weren't allowed to change them! I'm fairly sure it's none of his business, but it's less fun to put an inordinate amount of effort into pressuring him into allowing it, than just find a stupid technical solution.

but yeah.. we really should work on changing the meters over somehow.

[cybermuppet.livejournal.com]

I don't think it's his decision: they belong to the utility companies and you are their customer not him.

[wintrmute.livejournal.com]

however, work done to the house needs to be approved by him.

[cybermuppet.livejournal.com]

Except it's not: The electricity meter in particular is attached to a board that is also the property of the electricity supply company.

Since it costs nothing to revert to a pre-payment meter I can't see what the fuss is about.

[xxsimplethingxx.livejournal.com]

Let me try that again (with the right url in my clipboard!.. and btw wtf does "check spelling and preview" not actually preview?!)

I saw this article recently and thought you might be interested.

[wintrmute.livejournal.com]

thanks!
That's the next-gen Lego tech.. it's been talked about for a while, but it's still only coming out at the end of the year! :(
The current-gen Lego stuff is *still* selling for lots of money, sadly, even though it's about to be superceded.. (more's the pity.. in the end I didn't buy any lego mindstorms stuff, as even 2nd hand on ebay, it sells for 150-190 quid.. which is a lot for something to just check the gas meter.. I mean, we could just put 150 quid ON THE METER and never have to check it again! :)

[maelorin]

Any suggestions on other technology to use?

removals van?