Friday, June 28, 2013

Jumping bead chain: Slow motion doesn't always help

This video shows a weird phenomenon where a chain literally jumps out of a container as it spills onto the ground.  The theory is that the weight of the falling side pulls the chain out and in order for the chain to get out of the container it must go up before it goes down.  Since it can't change directions instantaneously it actually pulls itself up a bit before going down.  The super slow motion video is quite cool, but doesn't do much to make the phenomenon more understandable, at least for me.  (Don't get me wrong.  I still really want a super slow motion camera) It all looks quite magical.  I would love to try this, but I have no idea where to find 100 ft of bead chain.

Thursday, June 27, 2013

Twelve Tones of Vi Hart

Vi Hart's latest video, Twelve Tones, requires a bit of work to watch.  Unlike her previous videos, this one is 30 minutes long and it explores math-a-musical theory at some depth.  It is mind bending and numbing and worthy of all 30 minutes, but be prepared.   You need to be ready to spend a half an hour of intensely focused time to get the most out of it.  Enjoy the journey.

NASA IRIS Mission to launch this afternoon - see it live today!

Our star, the Sun that we see everyday, still holds plenty of mystery to us.  On that has been quite perplexing has to do with the temperature.  We know that at the surface it is very hot and that as you move away from the surface into the photosphere, it gets cooler, but strangely as you continue out through the atmosphere to the corona, it gets hotter again... several times that of the hottest spots on the Sun itself.  It isn't clear exactly what the mechanism is for this.

To help figure out this and other questions about old Sol, NASA has created the IRIS mission (Interface Region Imaging Spectrograph).  It is a satellite that will orbit the Earth in a polar orbit so that is always is exposed to the Sun and use its specialized instruments to examine the Sun.  It will launch today at 6:37pm PT.  We will be heading over to NASA to watch it live, but it will also be available online or on cable on NASA TV.

NASA Says:
IRIS will make use of high-resolution images, data and advanced computer models to unravel how matter, light, and energy move from the sun’s 6000 K surface to its million K outer atmosphere or corona. A fundamentally mysterious region that helps drive heat into the corona, this area has been notoriously hard to study. IRIS will be able to tease apart what's happening there better than has ever been done before.

The mission has three objectives:

1. Which types of non-thermal energy dominate in the chromosphere and beyond?
2. How does the chromosphere regulate mass and energy supply to corona and heliosphere?
3. How do magnetic flux and matter rise through the lower atmosphere, and what role does flux emergence play in flares and mass ejections?
More of the science of the mission is detailed here.

One of the really interesting things about this mission is how the spacecraft will get into orbit.  Rather than lifting off from a standing start as most space missions do, this one will be carried aloft by an L-1011 jumbo jet.  The plane will take from Vandenberg Air Force Base and take an hour to fly out over the ocean and gain altitude.  At a height of 39,000ft it will drop the Pegasus XL, a rocket that will boost the IRIS into orbit in a mere 13 minutes.  This launch method should save significant amounts of fuel and cost compared to a traditional launch.

Departure is planned to occur at 6:27 p.m. PDT and the drop of the Pegasus XL is targeted for 7:27 p.m. PDT on June 27.

You can watch live on the web starting at 6pm PT on NASA TV.

IRIS Mission home page
NASA IRIS Mission Web Site
NASA IRIS MIssion Overview
IRIS Educational Study Guide

(all photos courtesy of NASA)

Tuesday, June 25, 2013

Ice cube tricks for your entertainment

Ice Ice Baby!
In anticipation of a warm summer, we've been telling you about some chilly summertime ideas.  This post is similar and I hope you enjoy it, but it is particularly for my family.  You see, when I was but a wee tot, back in 19mumblemumble, one summer afternoon in a small town in Ohio, we had some drinks with ice cubes in them.  We drank these drinks with straws.  After the drinks were gone, there were a few ice cubes in the bottom of the glass.  Rather than waiting for the ice to melt, we found that blowing warm breath through the straws into the ice cube would make it turn to liquid more quickly.  Because the straw directed your warm breath in a particular spot on the ice cube, we soon found that you could basically drill holes in the ice with our breath.
Straw balanced by ice
As we played around, someone made a hole all the way through the ice cube.  This is where the fun began.   We found that you could balance the straw sideways across the rim of your glass with an ice cube suspended over the glass by the straw.  If you didn't center your straw, you would have a long bit of straw on one side being balanced by the weight of the ice cube.  As the ice cube melted, the weight distribution would change until, suddenly, the straw would tip over.  Based on this simple mechanism, we started creating machines.  When an ice cube melted, it would cause a straw to drop another ice cube onto a fork that would act as a lever to lift something else up and so on.  In the end we created an ice cube powered Rube Goldberg machine on our dinner table to build a sandwich.  The trickiest part was getting the toothpick to stick into the sandwich.  I'm sorry to say that this all happened before the internet and YouTube, so there is no history of this event other than what I have written here.

The video below is the closest I've seen to the ice cube shenanigans we performed that day.  It is only vaguely reminiscent of our fun day, and really is much more a rip-off of Eepybird (of Coke and Mentos fame including the two arm victory salute at the end).  Of course, even that is relevant for my family since our ice cube incident happened during a time when we hung out with Fritz Grobe of Eepybird before he got all famous and stuff.  Still it is entertaining and I hope you enjoy it.

For comparison here is the Eepybird video.... just sayin....

Controversies aside, summer is officially here and I hope the warm days make you appreciate the miracle of the ice in your freezer.  The ability to create ice through refrigeration (which we take for granted) has a long history that includes notables such as Benjamin Franklin and Michael Faraday.  During the winter it is so plentiful that in Sweden they build hotels out of it (see below), but during the hot summer, it is the technological miracle of refrigeration keeps our food and medicine from spoiling, gives us air conditioning and ice and generally makes life much more pleasant.  So during a particularly hot day this summer, take some ice out of your freezer and think about just how awesome it is that you can play with it as it melts away.  Enjoy!
Widdikay and Bix hanging out in the Ice Hotel in northern Sweden

Monday, June 24, 2013

It's time for Maker Camp

Are you a teen (or do you know a teen, or do you occasionally feel like a teen) looking for something interesting to do this summer?  You might want to try the virtual Maker Camp.  It's free on Google+.  It promises "30 days of awesome DIY projects and cool virtual field trips."  The camp runs from July 8th to August 16th on your computer screen. To join in on the fun follow Make on Google+ at  BTW, don't just watch... get out there and make something too...  We certainly will be checking it out here at Digital Diner.

Sunday, June 23, 2013

Ice Cream Sandwiches: You're doing it wrong!

I thought I knew how to make an ice cream sandwich, but it turns out I was completely wrong.  This is the proper technique.  Clearly I have spent my life merely watching shadows on the wall.  Excuse me, I think I need to step out to grab a pint of Ben and Jerry's,

Friday, June 21, 2013

3D Printable houses could be in your future

3D printers are awesome, but do you know just how awesome?  Imagine a giant 3D printer, so larger it can print a house.  That's right a house. The idea is that a large scale 3D printer that prints in concrete could extrude an entire house in about a day.  The video below tells some of the details of a system called Contour Crafting that does just that.

The cool thing about this, in addition to it being inexpensive, high quality and no requiring a lot of highly skilled labor is that these homes can be customized in software at no additional cost.  The nozzle squirts the concrete over here instead of over there and I've got a home theater where you had a study.   I think there may be something here.

I will say that  in the video, professor Khoshnevis also talks about incorporating wiring and piples into the building.  I think they need to be very careful here.  Stewart Brand's book How Buildings Learn talks about the different time scales of different parts of the home and the dangers of tying them to each other (wiring and pipes change faster than walls and thus combining them may cause problems).  I think there may be some work to do to understand all the implications of a printed house, but it certainly sounds compelling overall.  I think I'll go find a CAD program and start designing my dream house.

Read more here

what happens when you can make a camera that can track objects at really high speed?

This video is very impressive system developed by the folks at University of Tokyo.  It uses high speed video processing to track a ball at super high speed and directs mirrors to make a stable, high resolution image with the moving ball perfectly centered.   It gives you a very different feeling when you are looking at the scene almost from the point of view of the ball.  I especially like the addition of the projector to project an image into the ball.  Very impressive.  Finally we will be able to track the ball in golf/table tennis and the puck in hockey.

Tuesday, June 18, 2013

Dolphin rings make bath time so much fun!

Bubble rings, or dolphin rings or toroidal vortex rings, are cool circles of air that travel through the water sort of like smoke rings in the air.  This fellow at Cornell has figured out how to create dolphin rings in the water and in this video he shows you how to do it.

OK, it's all wonderful that this guy can make those ring, but did you see what the dolphins were doing?  No really... did you see that?  Wow!  I've never seen anything like it!  Here's another video on the phenomenon.

Apparently it's not just dolphins that make these and they aren't only in the water.  Bubble rings can be found in more places than you might expect.  Color me amazed.

Monday, June 17, 2013

I spotted Stanford's self-driving car

I saw Shelly headed over to Stanford last week
Last week on my way home from work, I spotted VW/Stanford's latest self-driving Audi TTS, Shelly.  These are the folks that brought us Stanley, the car that won the DARPA Grand Challenge back in 2005.  I managed to snap a picture (above) as it exited the highway.  The whole process would have been much easier if I had a self-driving car myself so that I could concentrate on taking pictures... maybe some day.  In the mean time, it was pretty cool to see this car since is is the one that raced up Pike's Peak and topped 120MPH on a track in Sacramento last fall... all driving itself.  Apparently the lap time on the track was comparable to that of a professional driver.  When I saw it on highway 280 last week, it was driving pretty gingerly; carefully using its turn signal and moving over to the exit ramp.

While self-driving cars aren't exactly common, one does see them around ever since they got the green light last fall.  There is always a driver in the driver's seat, but when in self-driving mode, they don't have their hands on the wheel.  It seems like I see the Google cars out driving fairly frequently, but this was my first time seeing the Stanford car.  It looks much more like a production ready vehicle because it doesn't have the big Street View camera on its roof.  I think it is all pretty exciting.

Those of you outside of Silicon Valley may not be quite so used to self-driving cars.  If you do, here is a little hint.  Don't get into an accident with one.  If you do, they have enough sensors and cameras to prove beyond the shadow of a doubt that you were at fault.

Workshop Weekend This Weekend

Workshop Weekend is happening this weekend in Oakland.  It's a fun maker-style event with classes in a bunch of topics including Arduino programming, genetic engineering, making ice cream with liquid nitrogen and cheesemaking.  Of course, if you are one of the few people who haven't yet taken the Awesome Aeroponics class, where you get to build your own hightech garden, that in itself is a reason to go.  It's certainly a fun and productive way to spend your weekend.  Hope to see you there.

For more information see the Workshop Weekend website

Wednesday, June 12, 2013

Ender's Trailer Recreated

Often movie trailers are pretty amazing.  After all, they take just the best parts of the movie and cram them all into a very short, intense couple of minutes.  So, if you want to make an amazing movie, you should make something like another movie's trailer.  Well, the folks at Cinefix do just that.  Most recently, they have recreated the trailer to the upcoming movie "Ender's Game."  (By the way, if you haven't read the book, you really should)
The video above shows a shot-for-shot remake of the Ender's Game trailer compared to the original.  It is very impressive.  Below is a behind-the-scenes video that describes how the project was done from start to finish.  I found that one even more impressive and particularly inspirational.  Take a look for yourself and enjoy!

Tuesday, June 11, 2013

Instant Ice Magic - Water Bending

This seems like the perfect way to amuse yourself and amaze your friends on a warm summer day.  It's a little bit science and a little bit magic, and it's literally cool.  It's instant ice!

It's pretty nifty to watch as the water molecules align themselves into a giant ice crystal right before your eyes.  We all know that  water freezes at 32˚ F (0˚ C), but the truth is a little more complicated.  You see water crystals form most easily if they have another ice crystal to connect to.  Usually this process is started ("nucleation") by building onto an impurity in the water.  Very pure water can get into a metastable state that is still liquid while it is below freezing.  A good whack on the bottle is enough to start the process off and then the ice crystals start forming on each other and you get to watch as the ice crystal grows right in front of you.  Try it and enjoy.  Let us know how it goes.

Monday, June 10, 2013

Underground Bicycle Parking

The video above shows a pretty cool bicycle parking system in Japan.  Apparently, in order to keep things neat, tidy and safe above ground, they have created a system to whisk your bicycle underground for safe keeping while you go about your business.  Pretty cool if you ask me.

Garden Monitoring Gadgets

A Previous Year's Tomatoes from our Garden

Note:  This is just a teaser.  A full how-to will follow some time in the future.

As regular readers know, we here at Digital Diner have grown tomatoes and veggies every summer for years.  Recently, we've been experimenting with hydroponics.  It has been pretty amazing seeing how our hydroponics plants perform compared to our more traditional, geoponic garden.  We are still learning, but the results are quite impressive with plants growing much faster, with no herbicides or pesticides and using only a fraction of the water of standard gardening.  There are some complexities, like understanding how to manipulate the nutrients etc, but overall, we have been mightily impressed.

The trusty old SunSPOT
watching over the tomatoes
One of the downsides of this type of gardening is that the plants have trouble quickly if there are any problems with the system.  If a pump or a fogger fails, in a matter of a couple hours the plants wilt and suffer dramatically.  For this reason, Widdakay and I decided to work on a system for monitoring our plants and providing live feedback on the web.  We could have used a prepackged system like Pachube COSM Xively which is designed for collecting sensor data, but what fun would that be?  No, we have to design our own system.  We have some experience with this since for years we have been montoring the tomato plants with some SunSPOTs and soil moisture sensors.  Now we have conceptualized a rather complex system and started to implement it.  It is still a work in progress, but we got far enough yesterday that I thought I'd report on it now.

To start with, we like graphs.  The graph below shows live feed from the sensors in our hydroponic garden.  Right now we have only two sensors connected, but we can easily support several more.  The blue line shows the water level in our ebb and flow hydroponic system.  When it goes high it means that the pump has turned on and water is pumped into the system.  When it drops down, it means water is draining out of the system.  In this type of hydroponic system that cycle occurs regularly when things are working correctly.  When the water level gets too low (due to evaporation) the pump wont turn on and we will see it here in the graph.  Later we will implement some sort of alerts to tell us of this condition, but for now it's just a graph.
The black line shows moisture level in one of our aeroponic systems.  It is using a soil moisture sensor, so it isn't exactly designed for measuring humidity, but it sort of works.  Generally speaking, if that line goes to zero for too long, it means that the fogger is not doing its job and we need to take action. If all is going well, the graph is being updated every few seconds while you watch right now and you should see the blue line periodically bouncing up and down while the black line squiggles around somewhere above 0.  If not, either we are working on the system right now, or we have a problem.

Note that you can scroll around, looking back over historical data, by moving the bar at the bottom.  You can change the time scale by dragging the sides of the region at bottom or clicking one of the buttons along the top left to look at the last 5 minutes, 30 minutes, 6 hours, 1 day or week.

The technology involved in making this system is quite complex, but amazingly quite available to us common folks.  The basic system architecture is shown in the diagram below:

Moisture sensor inside an aeroponic system
We use some inexpensive soil moisture sensors that we found at Jameco.  The systems we are measuring are hydroponic, which means there is no soil, still these sensors fit our needs pretty well.  We connected these to a ChipKit Uno 32.  The ChipKit is a new gadget here at the Diner.  It is a device that is code compatible with an Arduino Uno, but with a much faster PIC32 CPU and with a bit more I/O.  (Stay tuned for full review after we get more experience, but so far we like it).  We chose it for this task because it gives us up to 12 analog inputs compared to only 6 on an Arduino Uno.  A simple C program on this board collects the sensor data every 10 seconds through the analog inputs and sends it over the USB port to a Raspberry Pi.  (We may try replacing the Raspberry Pi with a BeagleBone Black in the future)  The Raspberry Pi runs a Python program that massages the data into appropriate formats and then connects over WiFi to stuff the data into a MySQL database on a server.  We then use a little Javascript and a very cool package called highcharts (free for personal and non-profit use) to plot the data from the database and handle the live updates.

ChipKit being installed on the ebb and flow system

All the code is in a GitHub repository that we will publish here when we get a little further along on the project.  For now, just let us gloat a little about the cool live graphs we got working this weekend.

Monday, June 3, 2013

This is a clever way for kids to learn to design electronic circuits

We've seen some great electronic design tools for kids come and go.  LightUp is a new one that uses magnetic components to create circuits that literally stick together.  That is great, but we've seen it before.  What LightUp brings that is new and quite clever is an augmented reality interface that allows the user to point a smart phone at the circuit and see animated "electrons" move around on their circuit to understand the flow of electricity.  Using the phone's camera and a little bit of augmented reality magic, the app can analyze the circuit and identify problems or illustrate the flow of electricity.  It looks very impressive tool to visualize and debug designs.  LightUp is a KickStarter that is doing quite well so far.  Take a look at the video below to see it in action.

Thanks Nacho