International Tabletop Day 2014

International tabletop day

International Tabletop Day

Want to hang out with a group of fun geeky people at a Hackerspace and play some awesome games? How about homemade snacks and homebrew beer? Still not awesome enough for you? Well, how about we hack an Xbox Kinect and scan you, then 3D print a custom game piece with your face on it, or make custom game counters on a laser cutter?

Come on by Pumping Station: One, Chicago’s biggest Hackerspace, on April 5th and have some fun and maybe even learn a few skills! Bring your favorite games, or if you want some supreme geeky-points, bring a game you designed and play-test it with us [we can even discuss how to spruce-up your game with lasercut or 3D printed pieces, hint-hint]!

This event is public, so bring your family, friends, or just awesome gamers you know and wanna hang out with! If you want to take part in making the 3D printed game pieces, or laser cutting custom counters, we do ask for a minimum of $1 suggested donation to cover materials. If you want to see this stuff continue into the future, please donate more! Proceeds will go to Pumping Station: One’s donation box.

31

03 2014

CNC Steampunk Harp – Getting Your Guts in a Knot – Part 3

 

Elizabeth and Ryan with a fully strung harp

Elizabeth and Ryan with a fully strung harp

[See Part 2]

At long last, the CNC Steampunk Harp that Elizabeth and I have been building is, at least functionally, finished! In previous posts, I documented the process of routing pockets in the side of the harp using PS:One’s CNC router, and our road trip to Sector67 in Madison, WI to use their seriously awesome laser cutter. This completed the work on all wooden parts of the harp, and so I could finally assemble it.

First, I had to glue the stiffener boards to the back of the sound board and used the drill press to make holes for the 33 strings. Gluing the sound board to the harp body required a lot of fast work: driving nails to hold the sound board in place, flipping it over and trying to wipe out the dripping glue while only having access to the inside via small holes, flipping it over to drive more nails, rinse, lather, repeat… all the while, the glue is starting to set. Then I glued the trim strips in place that covered all the nails. After that glue dried, I used a 1/4″ roundover bit on a router to clean up the sides of the sound box, and… oops! To my horror, I realized I forgot a step in the directions that said I was supposed to use extra nails to reinforce the area where the sound board joins the base near the pillar. Seeing as the harp has over 1000 lbs tension on the sound board and I really don’t want it pulling itself apart, I used the pneumatic nailer to shoot brads through the lower front trim strip. Then I needed to use wood putty to cover the brads. Oh, and did I mention that the angle of the nail gun wasn’t quite right and the brads poked through the bottom? So I had to bend them over with a nail set and cover those holes as well with wood putty. You live, you learn….

Read the rest of this entry →

25

03 2014

Caught in the Shop

I was walking through the shop tonight and saw something awesome happening. I took some crappy photos to show you (and I’m not sorry about it!).

That's a big piece of metal

Our Cold Metals area host, Mike, holding a big piece of metal. He’s going to turn it into a smaller piece of metal.

DSC_5730

Mike and Dean work on centering the piece.

DSC_5723

This is the part they’re trying to reproduce. This is a pulley for our new(ish) Johnson horizontal band saw. You’ll note that it’s bent. It’s also incorrectly sized, so there’s a bushing that’s been inserted that you can’t see. This bushing has no key, so the pulley was fairly noisy and inefficient.

 

 

25

03 2014

NERP: Playing with the BeagleBone Black

NERP is not exclusively Raspberry Pi, the small computer interest group at Pumping Station:One in Chicago. NERP meets every other Monday at 7pm at Pumping Station:One, 3519 N. Elston Ave. in Chicago.

Tonight at NERP, we’ll be playing with the BeagleBone Black. We’ll compare the look and feel of an original Angstrom Linux install with a fresh Debian Wheesy install. Beagles and their kin are complicated little devices, and there’s lots to see and try out (and fix) for a newbie user. We’ll sniff around the Beagle install and hardware just to pick up some landmarks for future projects and ideas.

 

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/
Doors open at 6:30pm. The next meeting is March 17th, 2014. NERP is free and open to the public.
Ed Bennett ed @ kinetics and electronics com
Tags: electronics, embedded, NERP, Open Source, raspberry pi, hackerspace, Beagle Bone, Element14, Pumping Station One

 

17

03 2014

Adding digital speed indication to a drill press.

There’s a big bin of 5 digit, 7-segment displays sitting in our electronics lab. It’s the sort of thing that cries out for a project. I found one that’s the perfect shape for a digital speed readout for our big drill press, whose mechanical RPM indicator was broken.

2014-02-16 18.26.53

Testing out the display PCB. It’s got 3 16 bit shift registers.

The display was pretty simple to reverse-engineer. There’s a header on the back that’s connected directly to the relevant pins on the first shift register. Apply power, fire up a basic sketch built around shiftOut(), and away we go.

2014-03-10 21.16.13

My test rig, showing that the RPMs pretty close.

My code (patches welcome!) is not terribly complex. Basically I use a Hall effect sensor to trigger an interrupt every time a magnet glued to a wheel in the drill press passes. The time between interrupts is used to calculate RPM.

2014-03-13 21.25.16

Magnet + Hall effect sensor.

All told, I spent maybe four or five hours on this project. It’s probably the simplest possible solution to the problem, and my total investment is less than $10 in parts. And we’ve got an accurate readout of the speed of this big drill press.

2014-03-13 18.49.28

Complete system.

I’m out

-loans

13

03 2014

NERP: At Last — A JavaScript MCU!

NERP: At Last — A JavaScript MCU!

NERP is not exclusively Raspberry Pi, the small computer interest group at Pumping Station:One in Chicago. NERP meets every other Monday at 7pm at Pumping Station:One, 3519 N. Elston Ave. in Chicago.

It was time, perhaps past time for a JavaSscript microcontroller to appear. Tonight Drew Fustini will show us a high-level overview of the Espruino. The Espruino controller board is just emerging from Kickstarter and can be ordered through one of their distributors. http://www.espruino.com/
Lots of people know JavaScript and its programming environment, and many of those people could be convinced to try their hand at using a microcontroller if they could use their preferred programming language – in a Web IDE. This is important stuff, but the really striking thing is that event-driven processes are now in easy reach of people who need the capability but don’t want to learn a real time operating system. A very common question people in their first hour of Arduino programming will ask is “Now how do I blink two LED’s?”. Having spent a lot of time teaching Arduino 101, I can say that it’s always an awkward moment when you say “Well, you can, but it’s really involved”. JavaScript combined with a bit of Arduino vernacular solves the problem in a way that might be expected in an event-driven system. It’s wonderfully short and simple. Snagged and slightly edited from the espruio.com site:

function toggle1() {
on1 = !on1;
digitalWrite(LED1, on1);
}

function toggle2() {
on2 = !on2;
digitalWrite(LED2, on2);
}

setInterval(toggle1, 400);
setInterval(toggle2, 456);

Each time you called setInterval(), it returned a different number. If you want to change how fast the interval runs (or cancel it altogether) you need to use this number:
changeInterval(1,1000);
or
clearInterval(1);
[end quote]

Almost predictably the CPU is an ARM M-series like so many other of the 32-bit MCU convenience platforms. For instance an M3 type is used in the Espruino and an M4 type is used in the Teensy 3.1. It is unclear to me whether portability of code will carry across different chip makers, but the M3 vs M4 difference per se may not matter. From Element14's community site:

...most features of the Cortex-M3 and M4 are the same with the significant difference that Cortex-M4 has DSP extensions and an optional FPU. There is nearly no need for modification of hardware and software to migrate from M3 to M4. [http://www.element14.com/community/docs/DOC-36208/l/migrating-from-cortex-m3-to-cortex-m4-by-element14 ]


Like the relationship between the Arduino and the ATMega MCU’s from Atmel, there is an Espruino board and Espruino libraries. Also similarly, the libraries are open source and theoretically portable to other boards using the same or similar chip. Some possibilities labeled as “unsupported” are listed on the Espruino site.
Will it become common to pick your ARM board and then pick your development system?

–----------

Also tonight, Ed will talk about some of the issues in making a clock that uses a funky, antique digital display called a “one-plane readout”.

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/
Doors open at 6:30pm. The next meeting is March 3rd, 2014. NERP is free and open to the public.
Ed Bennett ed @ kinetics and electronics com
Tags: electronics, embedded, NERP, Open Source, raspberry pi, hackerspace, Beagle Bone, Element14, Pumping Station One

03

03 2014

Bike Night – Fixing bikes in February

Hello everyone!  It’s been cold.  It’s been snowy.  But some of you people are still riding your bicycles.  Being cold and snowy doesn’t stop the need for maintenance.  Every other week is Bike Night at PS:1, and we’ve got our doors open for you.

Sometimes we bring in things to show off.  Sometimes we teach.  Usually we work on interesting bike projects.  (Learning how to wrap bars, building a bike from the frame up, etc) Last night was playing bike doctor more than “here’s fun stuff to work on.”  We had two patients last night.

Bike maintenance at PumpingStation

Bike maintenance at PumpingStation: One

 

 

 

 

 

 

 

Patient #1 received a new chain and sprockets to replace a stretched set.  And, the rider discovered the magic of clipless pedals last year, so replaced his platforms with some SPD pedals.

Patient #2 had some cheesy short term replacement pedals replaced with some very nice platforms, and had it’s headset rebuilt.

Does your bike need a tuneup?  Do you have questions about picking a new bike this spring?  Do you want to learn a new bicycle related skill?  Come visit us, we’ll be gathering in the shop March 5 at 7PM.

-Nerobro

20

02 2014

NERP: Spark Core – Warm and Fuzzy Computing

Monday Feb 17th at 7pm Jeff Camealy will present his talk “How to control your electric blanket with a Spark Core”. He describes his use case: “The Spark Core is a small Arduino compatible chip with built in WiFi and Cloud connectivity. This functionally can be used to easily create a device that can be controlled remotely. We’ll see how we can use the Spark Core Cloud to create an iPhone App to direct your blanket from the comfort of your .. blanket.”

nerp_spark-core-2

Lest Jeff sell himself short, it should be said that he’s spotted a technology that’s powerful and significant, but also somewhat strange. Until now the Arduino programming environment hasn’t often been associated with cloud computing. It’s not clear to me whether this is a niche application, or the start of a trend in small embedded controllers. Not surprisingly, the ARM architecture continues to insinuate itself into every corner of embedded control. The Spark Core uses an STMicroelectronics STM32F103 ARM M3 running at 72 MHz. The WiFi is provided by a TI SimpleLink CC3000 module. If you don’t like the cloud you can use the Spark Core as an ordinary USB-programmed controller that has WiFi. The spark.io site contains these [edited] points to help in understanding what the Spark Core does:

The Spark Core is a tiny, open source Wi-Fi development board that makes it easy to create Internet connected hardware. The Core is all you need to get started; power it over USB and in minutes you’ll be controlling LEDs, switches and motors and collecting data from sensors over the Internet!

There’s no need to ever plug the Core into your computer; you can write code in our web IDE and download it wirelessly to the Core. The Core uses Wiring, the same programming language that Arduino uses. Plus, with an accessory called the Shield Shield, you can connect the Core to a standard Arduino shield.

The Cloud is the mother ship that the Spark Core connects to when it comes online. Once the Core is paired with the Cloud, it becomes accessible from anywhere in the world through our open but secure REST API. Cloud service comes free for life with the Core. [excerpts from https://www.spark.io/]

Excitement!

Thanks to Drew Fustini and the kind folks at element14, we’ll have a drawing for a fully assembled Gertboard. “Gertboard is the ideal add-on for Raspberry Pi. Designed by Gert van Loo, it is a flexible experimenter board that plugs directly into your Raspberry Pi, and out into the physical world…” [element14]

NERP is not exclusively raspberry pi, the small computer interest group at Pumping Station:One in Chicago. Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/

NERP meets every other Monday at 7pm at Pumping Station:One, 3519 N. Elston Ave. in Chicago. Doors open at 6:30pm. The next meeting is Feb 17th, 2014. NERP is free and open to the public.

Ed Bennett ed @ kinetics and electronics com
Tags: electronics, embedded, NERP, Open Source, raspberry pi, hackerspace, Beagle Bone, Element14,
Pumping Station One

14

02 2014

NERP: Teensy 3.X – a 32-bit ARM microcontroller board for <20$

The Teensy name has been around for several years in the land of 8-bit MCU boards, but the 32-bit Arm platform introduced in Teensy v3.0, is a game-changer. PJRC (http://pjrc.com/teensy/teensy31.html)sent a few Teensy 3.0′s to Anna (our Electronics area host) at PS:1 with no discussion or fanfare. Thank-you, PJRC.

AT NERP TONIGHT, Ed will show the Teensy 3.0 hardware, Arduino tools, and some sample programs. After that introduction to the Teensy 3.0, Colorado Rob will show how he programs the Teensy 3.1 with a combination of tools and utilities from Eclipse, GNU, Freescale (manufacturers of the Teensy ARM MCU), and freeRTOS. ALSO – We’ll also raffle a new in box original aka white BeagleBone. Thanks to Drew for the donation!

The Teensy 3.X’s cost less than $20 and include all the peripherals you expect in a regular MCU. Some specs on the Teensy 3.1 are:

MCU MK20DX256VLH7 Cortex-M4, 72Mhz (96MHz overclocked), 256k flash, 64k RAM, 2k EEPROM, 34 dio pins, 21 analog input pins, etc.

The Teensy 3.0 is (mostly) pin compatible with the 3.1. The v3.0 uses an MK20DX128VLH5 MCU with 34 dio pins, 14 analog input pins, etc. Other spec values are one-half or less of the ‘DX256VLH7.

The 32-bit ARM chips are internally much more complicated than 8-bit processors, but the user doesn’t have to be aware of this when programming them. The Teensyduino IDE from PJRC provides a familiar user interface and Arduino(TM) libraries that make getting from zero to blinky very easy. There are additional libraries that provide access to some of the ARM-specific resources such as the USB port.

I’ve been exploring the v3.0 samples and am pleased with their sale price and performance. My setup is the basic Arduino install + Teensyduino on Linux. After doing the Arduino install I played with some sample code that does HID mouse and keyboard emulation on USB. Making it work was pretty straightforward.

Colorodo Rob writes:

I have been playing around with the Teensy 3.1 for a few days. It’s an ARM board for $17.
http://store.oshpark.com/products/teensy-3-1

My thoughts on it so far are that the CPU is way overkill for most embedded things that you’d program with the Arduino programming environment and library.* Also, there is a huge increase in complexity to overcome to program if using “real tools”. But the Arduino tools are easy to set up and use. But for my embedded project, the Freescale CPU it uses has the potential to save a bit of money. Even though the CPU costs more than the AVR part I currently use, it includes a USB controller and a voltage regulator, so those component costs go away. I’ve been following a tutorial for setting up a dev tool chain for these CPUs using Eclipse, GCC and Freescale’s tools:

http://mcuoneclipse.com/2013/07/20/dyi-free-toolchain-for-kinetis-part-1-gnu-arm-build-tools/

I’m looking at FreeRTOS (modified GPL) now. I’ve just gotten the ADC working with DMA which is pretty cool. My completion handler gets called when there are 32 samples ready for me, which is what I need for the carrier detect algorithm. The Freescale tools are pretty powerful for what they allow you to do, and an RTOS provides interesting departure from the sequential programming typical of Arduino development.

*Rob and I differ on this point…

NERP is not exclusively raspberry pi, the small computer interest group at Pumping Station:One in Chicago.

Find NERP and Pumping Station:One
at http://www.meetup.com/NERP-Not-Exclusively-Raspberry-Pi/
and http://pumpingstationone.org/

NERP meets every other Monday at 7pm at Pumping Station:One, 3519 N. Elston Ave. in Chicago.Doors open at 6:30pm.The next meeting is Feb 3rd, 2014. NERP is free and open to the public.
Ed Bennett ed @ kinetics and electronics com
Tags: electronics, embedded, NERP, Open Source, raspberry pi, hackerspace, Beagle Bone, Element14,
Pumping Station One

03

02 2014

CNC Steampunk Harp – The Sector67 Field Trip – Part 2

 

Finished Sound Board

Finished Sound Board

[See Part 1]

The sound board of the harp had always been the wild card. Elizabeth and I began the project last year knowing that we’d want to use a laser cutter to etch it with some kind of Victorianesque steampunk design involving gears. And we knew that PS:One’s Epilog, with its 24″ x 12″ bed and no feedthrough capability, simply couldn’t fit a 49″ sound board. While design focused on the brass panels, as we did have access to a CNC router, the sound board was left for later, especially because we didn’t know if we could find a smaller laser cutter with feedthrough, meaning we needed a design that could be etched in pieces, or a large laser cutter that could engrave the entire sound board at once.

Elizabeth and I were planning a trip to Madison, WI, and we heard rumors that Sector67 had a colossal Chinese import laser cutter. I reached out to them asking if they would be willing to help with this project, and Chris Meyer, director of Sector 67, responded, inviting us to their space. Knowing what we had to work with, Elizabeth was able to create the design in Adobe Illustrator. Read the rest of this entry →

01

02 2014