Let's Make Robots!

Rudolph's blog

Woohoo, more bot work done

A little more done, well, another phase started anyway, on my XMOS challenge bot(s).


From the bottom up, an ATMega168 @ 8MHz (with lilypad bootloader), a 74LS14 to put the schmitt trigger thingies on the wheel encoders, and a SN754410 H-Bridge to actually run the motors. Top-right is the KA378R05 3A LDO regulator.

Now to see if it actually works.


Servo+QRD1114 Wheel Encoder -- Fail!

I need wheel encoders on my current project. I believe that the gearing of the servo motors combined with the low weight of the robot won't allow the bot to roll by itself very much. Because of that I figure I don't really need full-tilt quadrature encoders. I also only have two of the QRD1114s, and I need two drive units, so each servo only gets one eye.

Finally doing some bot building

Yay, I finally am getting to work on my XMOS project. I've had a three foot stick of 1/2" x 3/4" aluminum angle stock for weeks now. Today I lopped two six inch lengths off, nibbled out some pockets for the servo housings, and drilled em. Reall impressive, eh? ;) At least it's moving along again.

Sneak Preview of Navigate & Map (NaM) (XMOS)

Well, here's the early beginnings of my Xmos project.

A dead PS2 mouse, a micro servo, a Sharp GP2D12, and a WowWee Bugbot.

Yes, this is half (well, okay, slightly less than half) of the project. Figure I'll just build one to start off. Once I make it work then it's easier to build the second one.

What to do...

17 no-longer-sterile tongue depressors, and five mini servos. This should be fun ;)


R3's eye, and trying to aim the robot

So I'm trying to add an "eye" to R3. Mechanically it's simple enough, I just stuck an LDR between ground and one of the analog inputs. Since the input has a built-in pullup resistor that should effectively create a voltage divider. No problem, that works as expected. Now I want the robot to spin in place, stopping every 45 degrees to take a light reading. Since the motors are just modified servos with no feedback it took some fiddling. After a bit of trial and error I find that running both motors for 300 millis rotates the bot 1/8 turn.

Another great idea that I didn't have

The Arduino Experimentation Kit (from oomlout) is a pretty damn slick thing. Usually I'm one of the shit talkers about Oomlout's stuff (they think a lot of their laser cut plastic). This thing isn't quite as pricey as I'd expect from them though. At 80 USD it _might_ actually be worth buying the kit instead of ordering parts from different places (and then paying multiple shipping charges).


aka Rudolph's Noisemaker Tool for Arduino

I wanted my current robot project to make cool bleeps bloops and other stupid noises. Instead of just doing it I spent three days writing software to make an easy job "easier". Well, okay, I spent two days doing it wrong, then switched to Python and tried again. This package is the end result. It consists of an Arduino sketch that makes noise from numbers, and a GUI Python frontend to make it "clickier" (oooh).

I really underestimated the creepiness...

So I've got "Dan" mostly built, just a few things remaining. Time to start working on the code.

As the title says, though, I really underestimated just how creepy this thing would look with this styrofoam doll head.


I'm gonna have to do something about that...


Here's my little prototype Arduino knockoff. I'm calling it the Pseuduino. Yeah, I know, the world doesn't need more Arduino knockoffs, but I don't care, I wanted one anyway! Besides, it was still cheaper than buying someone else's version (about 7-8 USD)(cheaper if futurlec would actually get parts delivered).