Let's Make Robots!

Chris the Carpenter's blog

CTC I am in the Make it Tweet Contest

Just thought I would drop a link...

I finally got around to Instructable'ing my Glen the Stove/ Twitter project. As it is, I needed to do so to enter in the Make it Tweet Contest. I did and I am.

Here is the linky-link.

Robot Test Facilities Have Been Provided...

Holy Geeze,

Did you guys know that there are places to do robot testing on just about every corner? They are all identical (everywhere) and can be counted on for solid, non-changing environments. They go by many names:

Prop Palm

Man, I am a sucker for cool little plastic boxes...

So, Nick from Gadget Gangster posted a link to this guy over on facebook...

Right off the bat, I wanted one! Then of course, I had to check out the supply house for the enclosure. That was a bad idea and yes, I am building yet another controller for walter.

Walter can play rock/paper/scissors!

We're gettin' somewhere...

This is Walter "docking" or stopping inside of a given area. I should say that in the video, Walter comes up quite short on the target. This is an issue with the beacon, not Walter. Walter judges distance from the beacon by judging the "size" of the beacon within the view of the camera. --As he gets closer, the dot of light gets bigger. When you put nice, fresh batteries in the beacon, it becomes super-duper bright and thus, Walter thinks he is closer than he is. I just need to get around to doing a bit of "regulation" on that beacon...


How to cut brass tube II --Making really short spacers

I used this trick for spacers as short as 1/8" and it worked fine. You would think that the brass tube would "drill itself" down, make the hole deeper and thus make longer spacers. In actuality, the blade prevents this from happening. The jig could be improved using real wood instead of MDF --a nice maple or ash would be great, but for now, it seems to work fine. The blade used in the video had already made around 40 cuts to the copper tube. --Pretty dull, actually and it still works fine.



Gilligan's "Delta Head" #fail

It's pretty simple, I have learned 3 things already in building a delta "pick and place" robot arm...

1) There seems to be a lot of math involved in making these guys move properly. I didn't know that going into this project. Hmm..

2) Every joint must deflect quite a bit, both ways, and in BOTH THE X AND Y directions. More than 45 degrees each way seems to be a minimum.

3) What Gareth is to polymorph, I am to brass tubing. Yes, after cutting (24) perfect spacers in a row, I am now the Tubing God. --Modest too!

Walter Jr. / Mini Me / Little Walter / Little Buddy / Gilligan

Yup, Walter needs a little buddy. With a WiiCamera onboard, Walter now has the ability to track and follow IR beacons and thus, could in theory, play follow-the-leader and hide-and-seek. But to play these games, he is going to need someone to play with! I bring you Walter Jr. aka Mini me aka Little Walter aka Little Buddy aka (the most famous "little buddy") Gilligan. The main deal with Gilligan is the fact that he has no budget. None. Nada. No money. He is going to have to be built out of whatever I have on hand.

Wii Camera and Easy PCB Etch How-To

Well, I got sick of having a lappy as a middle-man between my wiimote and my robot (via bluetooth). I decided to remove the camera itself and go with on-board i2c instead of sending BT data back and forth. Now, I have seen a lot of great "adapters" to go from the fine pitch of the wiicamera pins to "standard" pin spacing, but I need not only to adapt the pins, but also a good way to mount the device to the pan and tilt mechanism I have on Walter. I decided to etch a PCB for the task using, I think, the easiest PCB etching process around. Period.

Woo Hoo! New Tattoo!

Performance, Feedback, Revision.



Stringifying for Gareth

Here is my MP3 playing routine. It shows an int coming in, gettting converted to a string, and then assembled into a longer string which is then sent to the mp3 unit via serial. The only object you should need to make this work is "Numbers" with is sorta "Parallax standard".



Walter Update 2.11.11 Navigation Done

Woo Hoo! Navigation, headmoves and audio all about 90% there. There is still a lot of adding-to and cleaning up but it is very nice to be back to a solid base in which to work from. Much more personallity needs to be added, i.e. he should have something to say when getting stuck in a corner etc. The wiimote code I have been working on also needs to be added. The wiimote is being used solely for it's IR camera, using it to find an IR beacon. Basically, the beacon consists of 2 IR leds (constantly on) set 4" apart.

So my kid got me into programming...

I am learning Visual Basic.

Funny story, Phoenix somehow found a tutorial on youtube for programing a rock/paper/scissors game in VB. He was pretty excited about it, which is funny, Charlie is sorta the geek around here and the game itself really was not that spectactular. At any rate, we ended up downloading the editor and running the program. Went well, actually. I think he might actually get into this stuff.


Just got my boards back today. I did the seeedstudio 2x2 $20 deal and I guess I can't complain. No better or worse than SparkFun's boards, cheaper yes but almost 5 weeks to get them. At any rate, they are here and populated and work great. One of these guys is becoming a dedicated i2c servo-driver slave and another is going to be the new brain in the VEX transmitter. Super Nifty!

Gotta Start 'Em Young

I was putting together an order of PCB's to be made when my youngest, CharlieMac, became interested in the lay-out software I was using. I have to admit, it does look very cool when making a board --all those traces and pads, color coded... At any rate, I gave him a shot and he quickly (within 20 min) had figured out how the software worked. Being curious, I drew up a schematic on paper and gave it to him. Pretty simple, just a coin-flip circuit on a 08m. Ten minutes later, he had actually drawn it up... well! He got every connection correct.

Glen the Stove Project --Raw Materials

When I have mentioned my Glen the Stove project in the past, no less than 4 people told me that they just didn't believe that A) we actually use coal to heat the house or B) that anyone still used coal as a heat source. People do, and a big truck delivers it. Really, I am posting this video here for no other reason than the lift mechanism on the truck is awesome... It not only tilts like a regular dump truck, but it is part scissor-lift as well. They driver said the bed part of the truck was over 60 years old! Too cool.

LMR Live's Commitment to Quality

Always upgrading to bring you the best quality show you can get anywhere...

Propeller Journey 009

I2c is in the bag. Done.

Propeller Journey 008 maybe?

Encoders and The Man with Two Brains. (It was Dr. Huuhururrr by the way and I swear to God, I didn't have to look up the spelling).

So I am running 2 cogs now. One is running my motor and the PWM signal going to it. The other cog is keeping an eye on the encoder. I think the video is self-explainitory.


Prop Journey 005 SD cards and Serial data

Well, I can now get data from the computer into my propeller and write that data to the SD card. No fuss, no muss it is actually a very good system in terms of how Prop deals with data coming in. As I say in the video, this will be used to store all the pre-recorded "moves" that walter's head will do. I also mention in the video about EEPROMS --right now I can write a single byte to my EEPROMS every 5ms. The speed tests on the SD card put the write speed at 2M in .8 seconds. Think my resolution is going to get better?

CtC First Square Drawn with Little Bot

Yup, my "little bot" is up and running and has drawn his first square.  I am quite happy with the encoders and the absolute centering of the pen. I do think I need to do a bit more balancing of the motors (during the straight runs) and a bit more tidying up in general, but we are on the right track. Next on the list is to get my new lipo's installed (when they get here from China) and a servo to "pen-up" and "pen-down". From there, I would like to write a Processing program to allow me to draw a picture on the screen and send it off to the robot to draw.


CtC's Propeller Journey

Nick at Gadget Gangster was nice enough to get a Propeller chip (on a Gadget Gangster board) into my hands and I have now had a chance to start playing with it. Originally, a "review" of this board was planned and one still is but for now, I am simply documenting my journey into learning this chip and language. The propeller "system" and spin language are completly foregn to me so I am in a unique position of being a total beginner again.

Walter's new Navigation System (May I / Can I Go)

So here we go... I have been sick of "regular" navigation for quite a while now (more than a year now). The whole idea of "just keep going and if there is something there, react to it" is just not doing it for me any more. For the last year or so, I have been thinking about and working on a new system of "may I go". The theory is basic: Before you start going somewhere, check that there is somewhere to go! In the system I am using now, a 180 degree scan is performed and the sonar readings and angle is sent to processing.

Glen the Stove, Picaxe, Processing, Twitter and Thermsistors...

Yup, I got the Twitter-stove project done. The video is pretty self-explainatory and code is available upon request.

Glen the Stove on Twitter

It is a Nun... that changes colors.

Yes, I said a Nun...   ...and one who changes colors.

Give your Processing sketch a Voice!!

Hey Processing People!

I was playing around with my Twitter stuff and found this voice library at the processing website. Man, use this library! Nothing could possibly be simpler. There is the standard init stuff and then... ONE COMMAND!


That's it. Put anything you want between the ( )'s and it will be spoken. --I gotta say, for testing this is so much better than using a terminal.  --And the voice is not too bad either!


Dude, is that your plane there in the background? It is over his left sholder --with flames. I swear, the front end, the size and shape of the ailerons... I think they used the same plans!


Watch out for falling balls

I was looking at Pat's Chess bot post and noticed the link to the bearings he is using for his slides....

As a PSA, I thought you should all be warned:

CtC's Aurdino Journey

So I am in the Arduino water and have started to swim. I found a cheap off-brand Wii Nunchuk controller, made a PCB adapter for the plug and have it playing nice with my Duemilanove. I have also taken all the numbers coming from the nunchuk and converted them all to nice clean 0-255 ints. From there, I coded a serial receive loop so the whole unit could be used as a stand-alone plug-in to other devices. Basically, the chip just sits there and waits for a single character followed by a CR. I.e.

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Airplane Suggestion For a UAV

Hey guys,

Gareth and I were talking planes and UAV's the other day so I posted a quick video for him to watch showing one of my planes and why I thought it would be a good choice for a UAV. He suggested I post it for all, so I am.

The plane in the video is a Sky Surfer from Banana Hobby. Now, I personally hate Banana Hobby, but I must admit that this is one great deal on a plane... $160 gets you the plane, TX, charger, a brushless and an extra battery. The Sky Surfer is a rip-off of a Easystar which has been around for years.