Today's build - back to the CNC

For today's build I leave 3D printing behind and return to using my CNC.  For a while now I've thought about doing linocut with the CNC and today I'm giving it a try for the first time.  I first hand drew a Hilbert curve in Inkscape, then used it to design a stamp layout.  I saved it as a .dxf file and took that into CamBam to generate the tool paths and the gcode file.  I didn't know how things would go, so instead of testing it on an expensive piece of linoleum I first cut a piece of 1/2 inch plywood.  This is what it looked like after a little post processing to get rid of some fuzzies.

Next it was on to cutting the linoleum.  This is what it looks like with no post processing other than cleaning off the chips.  Linoleum cuts like a dream.  It doesn't make dust but chips, it doesn't fuzz like wood, it doesn't melt like plastics. The next step is to do some block printing with the linocut.

So, here's the result of that printing.  I have a lot to learn about block printing, I did about 10 prints and although not perfect, this is the best of the bunch.  It's printed on greeting card paper designed for a printer so it has a score line down the middle to fold and envelopes that match the size once folded.  I also did some prints of hand cut blocks that were smaller and did get some of those to come out great, so maybe smaller is the way to go for now.

Finished a woodworking project today

This long term project has taken several months but I finally finished it today.  It's a hairdryer and curling iron rack for my wife.  I made it from a piece of reclaimed maple butcher block table top.  The glue had failed on the top and left me with a bunch of 2x2 maple blanks.  I processed them and glued them up into wider stock for the rack.  The joints are simple glued up grooves with no mechanical fasteners.  It's held to the wall with toggle bolts in the drywall.

Yesterday's build - a world apart from robots

I actually started this build months ago when I did the coptic stitching on all the pages for my new journal.  Yesterday I finished it with my first attempt at binding the pages into a cover.  I also cut the linocut for the cover yesterday.  For a first attempt I'm pretty happy.

One day robot

In all my time building robots I've never built a line follower and thought it was about time. I figured the electronics from a Snappy type robot would work as a line follower, so I decided to give it a try.  I built up another board, re-configuring the light sensors to look at the floor this time.  Then I designed and printed a new chassis.  This is the result...

The software turned out to be incredibly simple, I just added about eight lines of code to the light seeking code running Snappy, and abracadabra the robot follows lines...

Snappy got his name from one of the Smurfs - I'll have to go through the list again and find another one for this guy.

Another Robot is Born Today

I posted stills of this little guy a while back when I finished the 3D printing and assembly but couldn't put up any video because I still had some soldering to do.  Well I got that done this evening, and he's up and running now.

His name is Snappy (one of the Smurfs) and he's a real simple ATTINY45 based light seeking robot.  I've got parts to build 7 or 8 more of these, so you may see some other variations in the future, but as is I'm pretty happy with him.

Sunday's build

Today I scratch built a FliteTest Mini Scout while watching the NFL playoffs.  It's small enough that I can fly it in the neighborhood park that's within walking distance of my house.  The build was pretty straight forward and went without a hitch.  I can't wait for the weather to cooperate so I can maiden it.

Introducing Pablo

Well, I'm calling my build of a BoB complete (for now), and I've named him Pablo.  I have another robot named Stella - after the character in the Streetcar Named Desire.  I also happen to have named my CNC machine Stanlee - after the famous Stan Lee of Marvel Comics.  I didn't know it at the time, but in the play Streetcar, Stella's husband is Stanley - So I thought it might be cool to stick with the Streetcar theme and name this little guy Pablo - after one of Stanley's poker buddies.

I had originally thought I would put leds in his eyes, but decided that would be too much and instead printed his eyes and pupils and just glued them on.  I installed his on/off switch in his backside, and I'm calling him done.  All he does right now is walk and I've got ideas for other behaviors, so I'll probably pick him up again some day for further work, but for now he is what he is.

One day build

Yesterday I not only got BoB's mouth working, I designed, printed, and assembled this.  It's an RC pan mount for my Mobius camera.  It's designed to be temporarily mounted to RC vehicles for onboard footage, and is inspired by Andrew Newton's video.  I won't go so far as to say everything on the design turned out as intended, and I will probably tweak some things and reprint it, but all in all I'd call it a successful one day build.

BoB's mouth - Custom PCB fabricated and installed

This morning I got the chance to etch, drill, build, test, install, and program the custom PCB that drives the led array for BoB's mouth.  These first couple images are of the board being tested on the bench, before going into the robot.

The leds mount to the back of the board and are spaced to fit in the holes printed into the robot's body.  This meant mounting the board was a simple matter of press fitting the leds into the holes, soldering up power, ground, data, and clock, and adding a few lines of code to the walking program to produce a simple pattern on the array.

The next step is to do *something* with the eyes - what I haven't decided yet, and decide on a name.

BoB's mouth prototyped

So the standard 3D print for the BoB robot comes with eight 3mm holes for the robot's mouth.  I've got some flat topped 3mm leds that go perfectly in these holes, so I figured that's what I'd do with them.  I want to be able to make patterns on the array and so need to be able to individually light each led.  Doing this directly with the Arduino eats up all the available I/O, and doesn't leave any room for expansion, so I got some MCP23008 I/O expander chips.  I figured I'd be making a custom board to handle the leds, so I ordered the SOIC package from Digikey.  I got a chance to work with them today and using an Adafruit SMT breakout pcb for SOIC I breadboarded the circuit and used the Adafruit supplied MCP23008 library to write some Larson scanner software.

The next step is to design and fabricate a custom board to fit the chip, leds, resistors, and all the connections into BoB's head.  After that he gets "eyes" with an ultrasonic sensor.

Newest build

We are visiting family over the holidays, and my father in law has a collection of some pretty nice tools.  I typically come with a project in mind so I have something to do while we're here, and this is the project for this trip.  It's a custom designed RC flight box with space for my transmitter, parts, tools, batteries, and propellers.  I didn't want to spend a lot of effort on it, not knowing how I'd like the design, so the construction is dead simple 1/2 inch ply wood with glue and nailed butt joints.  As you can see I still need a dowel for the handle.

Air boat on ice

Last summer I built an airboat out of pink insulation foam and scrap 1/8 plywood. With a -2 degree wind chill the pond is kind of "stiff" so I took the boat out onto the ice.  Turns out it runs pretty fast, but not really in a straight line for very long!

Newest Robot

On black Friday I got a great deal on a 3D printer.  One robot I've always liked that requires 3D printing is a BoB.  The design files for the mechanics are available on Thingiverse.  So not long after I got my printer set up and had a couple of prints under my belt my BoB came out.  Four 9-gram servos and some small screws later and the mechanics were done.  Everything went together without a hitch.

Then I added an Arduino Pro Mini, a boost regulator, a battery pack, a switch, and about an hour of programming.

I've got the 3mm leds for the mouth and the ultra-sonic sensor for the eyes, adding them is next, but that will have to wait until I get home from Christmas travels.

Testing my new Mobius action camera

I got a Mobius action camera for my birthday the other day.  I plan to use it mostly to flying video, but recently the weather has not cooperated.  Wanting to see it work, I mounted it on Clifford the little red robot and shot some video from his point of view.

Clifford the little red robot has new code

When I build robots I typically concentrate on the hardware and only write enough code to test the hardware works as I'd like.  I initially built this robot about 4-5 years ago, and he never really did anything interesting because I never invested much time in the software.

In the past few weeks I've spent some time programming the little guy, and have him to a state I can show to folks...

I have the motors, wheel encoders, servo, and ultrasonic distance sensor all working in a pretty well integrated behavior.  I still have some more work to do to smooth out the motion.  He moves in discrete steps now because the wheel encoders don't handle overshoot and I can't let him build up much momentum.

He's controlled with a Microchip PIC16F684 micro-controller programmed in assembly language with Microchip's MPLABX IDE.  I designed, etched, and built the board myself.  His body was purchased from Sparkfun.

Long time no post - making new boards

For the past couple years I've been building and flying RC airplanes.  Recently I've been thinking about getting into night flying.  Doing so would take lots of LEDs on a plane, so I've been building an LED driver circuit.  I just got the parts in the mail today and put together the driver above.  It will drive 11 different led circuits and is the size of a 24 pin 0.6 inch DIP.  I chemically etched the board using toner transfer and hand soldered all the SMD parts.  The Eagle files are up on Google drive if you're interested.

Holiday Hacking Bender - Day 6 - Project 2

I've been thinking about this project for a long time.  Many years ago (mid to late nineties) I took a lot art classes just for fun.  I explored a lot of media including drawing, ceramics, photography (we used a thing called "film" back then), but my favorite was jewelry.  I did mostly fabrication, and specialized in lockets and other enclosures.  One enclosure I've always been fascinated by is the reliquary. I'm not sure of the Webster's definition, but I see them as a small secure places to keep something ancient and treasured.  Now, one of the things I've always held with that group of ancient and treasured objects are stones containing carved petroglyphs.  I'm thinking a stone bearing a personal totem encased in a wearable reliquary would be a brilliant piece of jewelry.

Jump forward to today, or at least the recent past, when I finish putting my ShapeOko together, and the first thing that occurs to me is "I wonder if I can get it to carve petroglyphs?".  Today's project is the beginning of that exploration. I don't want the glyphs to look machined, so I'm attempting to build a vibratory hammer type thing.  This version is a simple electromagnet with a hardened steel plunger retracted with a rubber band.  After playing with this today, I'm not sure I can get this design to go fast enough.  I might need to go to active position control of the plunger.  Right now the control circuit is a 555 driving a TIP120 - pretty simple.

Holiday Hacking Bender - Day 6 - Project 1

The first project of the day was pretty simple, but meant a lot.  A couple of months ago my son Nathan spent his allowance on a Raspberry Pi.  He mostly got it because he heard he could learn to program Minecraft on it, but he's also into Snap-Circuits, and other geek stuff, so for Christmas I got him a pi case, cobbler, and getting started book from Adafruit.  He also got his own soldering kit, so this morning I helped him through putting together his cobbler and getting his pi into the case.  The he wrote some python to make Das Blinken Lite Machine.

Holiday Hacking Bender - Day 5

Not Such a Good Day

I had planned another wood working project for the day, but couldn't stand the idea of doing it with the state my shop was in.  I spent a great deal of the day cleaning and organizing the shop, and ran out of energy before I got anything made.  Yes - things were quite the mess, and still not completely straight.  I need to build some tool cabinets before I'll be able to organize everything the way I'd like.  I will make up for the lapse by making two projects today, day six.

Holiday Hacking Bender - Day 4

What you see is the result of today's efforts from the electronics department. Things went pretty well there, and I feel pretty good about the build. The brown board on the left is obviously an Arduino clone. I build the little "micro shield" to provide a robust plug in for an I2C interface. The little green board on the right holds an MLX90614ESF-AAA Infrared Temperature Sensor. It's connected to the micro shield with an upcycled USB cable, so the sensor can be some distance from the Arduino.  Right now it's just running an example sketch I shamelessly stole from bldr.blog.  Then, not being satisfied with stealing only a little I went out to an Australian Robotics site I found through ThingSpeak and stole some more code to post the temperature data to a channel on ThingSpeak.

So, the electronics department delivered, and the software department, after having been abused by assembly language programming all day yesterday, lost all sense of moral direction and stole everything, so in a way they delivered.  The manufacturing guys though, just couldn't pull it off today.  I had intended to build a desk lamp like articulated arm to hold the temperature sensor in varying places and orientations.  I got the design done, the g-code is even available, but my CNC just would not cut the parts.  After two attempts, each of which took more than an hour of cutting time. I decided to just give up.  I think the machine has a problem with static build up or is haunted, because on longer cuts it just intermittently looses its mind.

Anyway, that's all for day four, see you again tomorrow.