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.

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

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!

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.

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.

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

Super Awesome Sylvia hearts you

The latest from the ever-effervescent Super Awesome Sylvia has you building a necklace that displays your heartbeat.  I think it could do with some more elegant packaging if you wanted to wear it on a regular basis, but I really like the idea of biometric jewelry.

If you haven't experienced Super Awesome Sylvia, it is worth your while to check out her site.

I've never seen a flying car like this before

This is a rather unique model flying car.  It is both a wheeled vehicle and a quadcopter.  Some of the design ideas are really interesting.  For example, this is the first time I've seen anyone use the space inside a hubless wheel effectively (in this case to hold the quadcopter propellors).  The wheels and props are flexible and nearly impossible to break.  It may not be the best car or quadcopter I've ever seen, but it is certainly the best combination of the two I've ever seen.

See the Kickstarter here.