greetings everyone

[horar]

Hi from Tasmania,

I've already documented much of what I'm doing on my website

asmith.id.au/robotics.html

Mostly I develop web applications and databases such as

tracktype.org

however I do spend as much time as possible tinkering with robots too.

Cheers,
Andrew

[Bones]

Hi Andrew,
Nice work you have on your site.
I like the alloy robot "Ally". lol. I just got the name.

I like the site too. Nice and clean feel to it.
Except the google ads. lol.

Cheers
Bones

[Robotman]

Hi Andrew

Welcome. You might have to shout a little around here because we're all separated by such large distances! And I think all the different time zones don't help much either...

I've just been looking over your website. I'm curious as to exactly which herbs you've been growing in your hydroponics setup. You didn't really say

I'm curious to know more about your "tacho" for the GIR robot, especially the circuit details. The photo shows what looks to be a neat little circuit. Does it work reliably? Up to how many RPM will it operate? Does the black disc use Gray encoding?

Cheers
Botman

[michaelg]

Hi Andrew,

Welcome mate

[Dingo]

G'day and welcome.

GIR and Ally certainly look interesting.

[horar]

I've drawn up a schematic for the wheel encoders used by GIR. You can find it at asmith.id.au/images/wheel-encoder.png

For ALLY I'm working on a new method which directly measures the motor current in order to calculate speed of rotation and (hopefully) the wheel position. The schematic for that is at asmith.id.au/images/motor-sensor.png There is also a photo of the motor signal displayed on a 'scope at asmith.id.au/motor-sensor.html

[Robotman]

Thanks for the schematic of the wheel encoder, horar.

You are going to have some curvy looking graph tables to consult when using current consumption to determine motor rotation speed! I certainly wouldn't fancy trying to capture all that data under real world conditions - straight wood floor, straight shaggy carpet, straight grassy lawn, cornering on a concrete slope, cornering on a sloping grassy lawn, left then right and reverse, and finally doing it all again for the other motor. Phew!

Unless of course you are planning on having the robot autonomously learn how its motors behave. (Goal seeking and reward - if the robot gets there using the least amount of current then it has learnt the optimum motor control strategy.)

Cheers!
Botman

P.S. Has anyone guessed that I've recently been trying to use up *all* of the smilies that are available?