Raspberry Pi

[al_cam]

Got email on Monday to say mine was despatched (from RS) after nearly 10 weeks.

Checked today and the Parcelfarce website says it has been delivered - even shows forged signature which is nothing like mine!

Trouble is, I live in the middle of nowhere and Parcelfarce deliver here all the time so know where it is and I was in at the time they say they delivered. Something seriously dodgy going on.

[SupremeSpod]

I finally got my arse into gear and did something with my RPI last night. Picked up a cheap class 10 16gb sd cart in pc world then installed XBMC on it. I now have it talking to my serviio media server and it works a treat. My tv even talks back to it over the HDMI so the remote control will control it and when the RPI is shut down it turns off the tv, all very neat

Clever, init?

[al_cam]

I see the Model A is now available. a whole £6.04 cheaper than the B (on RS at least)

link

no ethernet connector (or chip), only 1 USB and only 256Mb RAM, main attraction is that it uses a lot less power but I can't help feel it is largely a waste of time. I think they missed an opportunity to also remove the RCA and audio sockets and replace the full size SD slot with a microSD one and reduce the size of the thing (and further reduce the cost and power consumption)

Anyway, my sons and I (well mainly I) have been having fun making a Pi controlled lego car controlled with an android app. Currently no steering and uses 2 lego motors which rotate at different speeds so it doesn't go in a straight line. Need to design some kind of lego steering system and add some gears to distribute the power from a single motor to the wheels but not sure a single motor is powerful enough by the time you make a car big enough to hold the pi, an L298N, a battery for the Pi and one for the motors.

If anyone is remotely interested I can share what I have done so far. it's a great learning project for kids - although a bit beyond an 8 year old's grasp. My kid's pals nearly wet themselves when they see it though - it is pretty cool.

Al.

[SupremeSpod]

I see the Model A is now available. a whole £6.04 cheaper than the B (on RS at least)

link

no ethernet connector (or chip), only 1 USB and only 256Mb RAM, main attraction is that it uses a lot less power but I can't help feel it is largely a waste of time. I think they missed an opportunity to also remove the RCA and audio sockets and replace the full size SD slot with a microSD one and reduce the size of the thing (and further reduce the cost and power consumption)

Anyway, my sons and I (well mainly I) have been having fun making a Pi controlled lego car controlled with an android app. Currently no steering and uses 2 lego motors which rotate at different speeds so it doesn't go in a straight line. Need to design some kind of lego steering system and add some gears to distribute the power from a single motor to the wheels but not sure a single motor is powerful enough by the time you make a car big enough to hold the pi, an L298N, a battery for the Pi and one for the motors.

If anyone is remotely interested I can share what I have done so far. it's a great learning project for kids - although a bit beyond an 8 year old's grasp. My kid's pals nearly wet themselves when they see it though - it is pretty cool.

Al.

How about building a trailer for the battery?

[Platypus]

Referring back to a project I did at school 30 years ago, could you monitor the rotation of the wheels and adjust so that they rotate at the same rate thereby allowing it to drive in a straight line?

In fact with such a mechanism, could you vary the motor speeds to deliberately to steer it?

IIRC we did something with a light sensor.

The Lego NXT motor seems to have sensor capability, NXT Sensor Guide

[vetran]

Referring back to a project I did at school 30 years ago, could you monitor the rotation of the wheels and adjust so that they rotate at the same rate thereby allowing it to drive in a straight line?

In fact with such a mechanism, could you vary the motor speeds to deliberately to steer it?

IIRC we did something with a light sensor.

The Lego NXT motor seems to have sensor capability, NXT Sensor Guide

get a cheap ball mouse to take apart.

It will have 2 slotted wheels and a slotted IR opto switch that produces a pulse each time the slot passes.

Or a magnet and hall effect device(1 per revolution) pretty sure someone has done that on raspb pi.

[al_cam]

Thanks all for your suggestions. I will definitely investigate the other goodies lego NXT has to offer.

I have improved things significantly by using older lego motors and also by running both motors from the same outputs on the L298N (which also frees the other outputs for the steering). The difference in speed was a combination of both things but mostly the modern motors.

Now to sort the steering out...

Al.

[al_cam]

The ZeitBuggies I inflict on the esteemed customers are steered using the drive motors, with a castor type thingie at the front.

Right one on to go left, Left one on to go right, both on to go forwards.

Simples & avoids the requirement for a steering motor.

ZeitBuggies? sounds interesting - please tell more.

Interesting idea. As a quick experiment I did try something similar but with a fixed rear axle, it just ripped one of the motosr off. I assume your buggies don't go very fast as I imagine they could easily fall over (I'm laughing thinking of Top Gear now). I could easily make the whole 2 wheel rear axle rotatable though - can't wait until I get home now.

[Scrag Meister]

Was speaking to a friend of my daughter, who left after GCSEs and got an apprecticeship with some local government department. She loves IT.

They are trying to create an adult learning scheme to introduce programming using Raspberry Pi, presumably because it is a cheap machine, although she did say with a keyboard, screen, mouse, SD card etc it added to the price quite substantially.

They are looking at Python as the language, what builds do you use? Ubuntu unix? GUI? IDE?

I'm not a Python or Unix user.

I did say that the Pi is a bit of a geeky solution and not really aimed at the main stream, although with time, and some more user friendly setups it would improve.

[SupremeSpod]

I run "Raspbian" and try to stay clear of Python.

However, Python and "Minecraft" go together quite well