Thursday, May 18, 2017

Creeper Chassis

I'm working on a project for my "Minecraft for Makers" book. It's a robot version of the iconic Minecraft monster, the Creeper.

I began with the Bogie Runt Rover kit from Servo City, which is 100% compatible with Actobotics channels. I'll put an Arduino, motor shield, and battery pack underneath the ABS plate, with a servo turning the head with a 1/4"x12" steel rod.

Building the guts of a robot that needs very specific outside proportions to look right, was definitely a challenge. It amounted to figuring out where to attach the wooden "skin" to the chassis so that it looks perfect as well as functions right.

I'm also designing a simple controller that I can use for multiple projects.

Monday, April 27, 2015

Actobotics Expert Challenge--Parts List

 I'm participating in the Actobotics Expert Challenge , where five builders each gets $1,000 in parts to build a labor-saving or home automation machine. I just ordered my parts and when they come I'll do an unboxing, but here are some standouts:

 Channel: Actobotics' signature element is the channel and I bought a bunch. I got a pair of 24-inchers just because; I didn't need them for my project. The chassis consists of mostly 18" and 9" channels, and I bought 4 and 7 of these, repectively. I got some channel mount gearboxes that use 3.75" channel legths if you don't have them in a bigger one, so I grabbed two of these. Finally, I'll be moving a platform with a belt and pulley, so I got a 1.5" channel length for the pulley.

 Servos: I messed up and failed to buy a continuous rotation servo to move the belt, so I'll have to figure that out later. I made up for it buy buying the aforementioned channel mount servos, which are ridiculously expensive and probably more powerful than I really need. Pricewise, they're $125 each when you factor in servo programming and gearbox assembly.

I mentioned that I didn't buy a servo to turn the pulley. That is not 100% correct because I did spring for this rather sweet HS-646WP waterproof servo, has 161 oz-in of torque, and can be immersed up to 1 meter. The only probably is, the servo has only the stock 90 degrees of rotation and would need to be reprogrammed for continuous rotation. If I don't have time, I'll just buy an el-cheapo continuous rotation servo because the motor's robustness really doesn't matter that much in this application.

Bearings & Shafts: The platform the belt is connected to rolls on rather cool linear ball bearings with 8mm inner and 15mm outer dimensions. I got 8mm x 300mm shafts for them to run on, as well as clamping hubs for each end to secure them. Now that I write this, I think I may have forgotten to buy the hardware (presumably tube clamps) to attach the bearings to the platform. However, I may just end up 3D printing some.

Attachments: Part of my difficulty in choosing my parts was that I had a hard time visualizing how to attach things together. What sort of mount would I need for this element of the project? What kind of attachments do I need to bolt things together? Not being completely sure what I'd need, I got a whole bunch of screw plates, the attachment of choice for Actobotics. I got 10 large screw plates and 20 dual screw plates, plus 48 single screw plates. For screws I opted for Actobotics-standard 6-32 socket-head screws; I got 200 of these, all in .375". I have a bunch of other sizes already, but found myself always running short of the smaller screws, which is mostly what Actobotics uses.

I have a lot more observations to make about my order, but that's good for now! I'm excited to be a part of this fun contest.

Thursday, January 1, 2015

Trinket EDC Contest

I'm hoping to submit a project to the Hackaday Trinket EDC contest, the deadline of which is coming up. My project is mostly done so I feel fairly confident, unless it flat-out doesn't work, that I'll be able to finish in time. Basically, it's a simple Trinket-based digital synth that fits inside a Nivea tin. I created a PCB and manufactured it through OSH Park. So far so good!

Wednesday, December 10, 2014

What's in my Bag?

I wrote a short piece for Cool Tools describing some tools and gear that I haul around when I'm working on projects. It was fun thinking about the stuff I use on a daily basis, and fun writing about it! Thanks to Mark Frauenfelder for the opportunity.

Monday, December 8, 2014

Maker Pro is Off to Print

Maker Pro is a book of essays I worked on this summer. There are a bunch of really fantastic essayists, interviewers, and interviewees who contributed and I'm very stoked how it turned out.
And it is off to print now! I can't wait to see it as a physical book--it's always a thrill. If you're interested in checking it out, you can buy it on Amazon and (likely) the Maker Shed.

Sunday, November 16, 2014

Unboxing the Makeblock 3D Printer

I recently was sent a Makeblock Constructor 3D printer.

It’s version 1 of a clever and ambitious project by Makeblock, a Shenzhen-based OSHW startup that primarily manufactures a set of awesome beams. The beams are extruded aluminum, a variant of t-slot, with some great added features like threaded slots, threaded end-holes, and mounting holes along their length with the same spacing as Lego Technic beams.

What Makeblock did was add RepRap hardware (a RAMPS shield and LCD display) to a Makeblock chassis, calling it the Makeblock Constructor. It sounds like a great approach to get into the field of 3D printing!

The first thing you should know is that the Constructor is a kit; you’ll get two big boxes of aluminum beams, stepper motors, wires, and so on--400 parts total. The kit doesn’t have anything super challenging in terms of tool or skill use. Being able to drive screws and follow directions will get you through the kit. However, there is a lot of it. You could build it in a day if you worked hard at it.

So, I got my sample kit and opened it up to see what was inside:

In a future post I’ll describe actually building the kit.

Saturday, October 11, 2014

The Locksmith's Apprentice

I’ve been writing fiction forever, mostly for my own amusement and never shared with anyone. About three years ago, I finally decided that I wanted to write a fun and quick novel to publish, just to prove to myself that I could. So I wrote a book I wanted to read, which is a frequent suggestion of successful writers. Apparently I wanted to read an adventure with a plucky thief as the hero, a stalwart heart in a magical and perilous fantasy realm. Titled The Locksmith’s Apprentice, it’s story in the pulpy fantasy tradition of Michael Shea's Nifft the Lean, Fritz Leiber's Nehwon books, and Michael Moorcock's epic fantasies. It’s chock full of manipulative sorcerers, assassins, priests, plots, and duels.

I had help along the way. My wife Elise has always been super supportive of my writing, particularly of “non-earning” stuff like fiction. My friend Drew read a chapter a week, sometimes more, and this really encouraged me to keep going. My mom Barbara read the first draft, as did Adam, Jude, Xander, Cam, and Ned. My mom and Ned also supplied really valuable proofing.

I want to especially thank Cam Treeby, who drew up some cool concept art for The Locksmith’s Apprentice before I had even finished three-quarters of the book. It was very inspiring to see characters who had scenes yet to be written. Cam is a paratrooper-turned-illustrator with a very deft pen and ink style. You can see his work all around the Hack Factory, where he is an active volunteer. I strongly urge you to hire Cam to do art for you!

After thinking about it and looking for an agent, I decided to self-publish the book on Amazon, mostly because I didn’t have any contacts in the fiction publishing world. All of my books were technical up to this point: robots, Legos, microcontrollers. I just wanted to get it out there and move on to the next project. If it doesn’t sell, so be it!

That said (ahem) I’d really love it if you would buy my book on Amazon. I don’t have it anywhere else right now, but if you can read a Kindle book, you can get The Locksmith’s Apprentice.

Thanks to everyone who made this possible!