Blaine's Blog | tech_ramblings.random()

Creating a new site to consolidate NFL stats, RankRecord.net

22nd September, 2015 · iblaine · 1 Comment

For this NFL season I created a site to consolidate NFL rankings, RankRecord.net. The goal is to create one page that automatically updates itself with all the rankings I normally check during the season. Over time I’ll add other sports but for the next few months it’ll be football stats. Currently the site will automatically consume various NFL Power Ranking results, add the results in MySQL then push the ranking values to a .csv to be used with D3.

The D3 graph is setup to be dynamic such that it will consume any number of sources such as ESPN, FoxNews, Bleacher Report, etc. If a new source is introduced to the graph, then the graph will automatically create a new column of option boxes for that new source. This is good because it eliminates the need to modify the graph each time a new source is added. However there’s a cost and that is color management. Ideally each team has their own color but there’s no limit to the number of lines on a graph. So to make each line color, the colors are chosen from an array. The site is also not very mobile friendly. It is what it is. But the backend is cool.

The dots in the d3 chart are red if the team loses and green for a win. The colors are dynamically chosen because the source data is dynamically created. One week there may be a dozen sources of power rankings, the next there may be a few. So…it’s a work in progress…

Frame construction for the Walking Bike

10th September, 2015 · iblaine · Leave a comment

Part 1: Building a Walking Bike / StrandBeest Bike

Part 2: Leg construction for the Strandbeest Bike

Part 3: Frame construction for the Walking Bike

Part 4: The Walking Bike is Finished!

Each walking leg of the walking bike consisted started with long metal pipes. Pieces were cut from the pipe, fit onto the jig, then welded together. More or less we were building legs one bone at a time and eventually we had built four legs. Not too difficult of a process, just time consuming.

The crankshaft was put together in pieces. Having 4 walking legs more or less dictated the shape of the crankshaft. We wanted two feet on the ground at all times. This mock up using a wire kicked off that process.

These pieces would eventually make up the crankshaft. The difficult part about making the crankshaft is it had to be precise. There were a lot of pieces that went into this one crankshaft. So mistakes would add up. To make matters worse, the heat from the welder bent the crankshaft. After each weld we essentially had to start from scratch, bending the crankshaft into the necessary shape.

The brackets were to attach the legs to the crankshaft. The legs were pushed by rods much like a connecting rod in a car engine. To get the rods to attach to the crankshaft, we had to build brackets. The brackets are metal clips that are held together by small bolts.

The purpose of the hub is to attach the crankshaft to a chain. We cut the hub out of 1/4 steel.

The push rods that will connect to the walking legs are being completed.

Here the legs are being dissasembled in preparation for buliding the frame.

We ended up going with a bike from Walmart. The legs themselves can be detached and attached to most bike with a few bolts but this bike is more or less the permanent home.

Removing the spokes from the rear wheel hub.

The legs attach to the frame in many locations. The frame attached to the bike in two locations. Not pictured here, but the frame will eventually have a rear wheel hub. Then the top of the frame attached to the seat post.

The start of the crankshaft is a collection of un attached pieces. Here magents are being used to hold the pieces in place to prepare for a weld.

The welding heat would bend the crankshaft out of place so we tried our best to reheat it to its proper shape.

Fitting the frame to the bike for the first time.

Some mistakes were made along the way. For exmample, bolts were used in the leg joints. And the bolts were too long to fit through the frame. The bolts were cut. The bolts clearly did not fit the frame once things were put together.

Back to the frame. While the frame could marry the bigs to the walking legs, the frame needed support to do so. Here welds are being put in place to keep the walking legs from bending.

Bushings are used to minimize the friction when the legs move. To do that plastic pushings were used from www.igus.com. I ordered a little of every bushing that may help then did a bulk order for those that were eventually used. Wherever there is a point where metal touches metal, bushing are used to decrease the friction. In all there are around 120 bushings used for the 4 walking legs.

Riding the bike for the first time.

The feet of the bike were made by cutting a pipe in half, cutting strips off a bike tire, then using a rivot to attach the rubber to the pipe.

2 coats of Metal Finish
2 coats of Carbon Mist…more or less black with gold flakes.
2 coats of Clear

Painting was done over the course of two weeks.

This bottom part of the frame attaches to the rear bike hub.

This top part of the frame attaches to the bike post.

Packing up the bike for a demonstration across town.

The walking bike finally assembled.

By coincidence, the 2015 Solstice parade in Santa Barbara was right around the same time the bike was finished. And the theme for the year was Aliens.

Building a Hovercraft

2nd September, 2015 · iblaine · Leave a comment

So…circa ~2000 two friends and I built a hovercraft. I’m resurrecting those photos because it was such a cool project. Why build a hovercraft? As Daryl put it, we wanted to see if those ads in the back of Popular Mechanics were real. And we were young with a lot of free time.

Here is a summary of the construction process that went into building this hovercraft.

Concept
What would we build, who would be involved, where would the hovercraft be built, what kind of tools were available, what tools would need to be acquired, what would be the cost, how long would it take to build.
Preparation
Buy the hovercraft blueprint, buy materials, buy equipment, set up the construction area.
Frame Construction
Construct the wire frame of the hovercraft.
Hull Construction part 1 of 2
Create the sides and bottom of the hovercraft.
Lift Duct Construction
Create the lift duct cavity.
Thrust Duct Construction
Create a thrust duct frame.
Propeller Construction
Fabricate a lift propeller and a thrust propeller.
Fiberglass
Coat the hovercraft in fiberglass.
Lift motor mechanics
Acquire a lift motor, mount a propeller onto the motor then mount that to the lift duct.
Thrust motor mechanics
Acquire a thrust motor, mount a propeller onto the motor then mount that to the rear of the hovercraft.
Operational mechanics
Create mechanics to operate engines and steering.
Steering mechanism
Create foam fiberglass fins to steer the hovercraft.
Cockpit assembly
Create a place for a driver and passenger to sit as well a create mechanics needed to operate the hovercraft.
Skirt construction
Create a skirt from rubber and attach the skirt to the hovercraft.
Flotation
Add inflatable plastic containers to the hull of the hovercraft for floatation.
Hull Construction part 2 of 2
Create the top of the hovercraft and walls of the cockpit.
Testing and water proofing
Test the hovercraft and implement water proofing to allow the electronics to operate in salt water conditions.
Trailer construction
Create a trailer that will transport the hovercraft and add any necessary lighting/turn signals.
Painting
Paint the trailer and hovercraft.
DMV visits
Work with the DMV to license the trailer for use on the streets and license the hovercraft as an amphibious vehicle.
Maintenance
Every hour of operation required about 3 hours of repairs. Most repairs went towards patching the lift skirt and fixing dents in the propellers.

That sums up the major categories of effort that went into construction of this hovercraft. The entire process did not have any major hang ups. At first it was frustrating to come across situations that were not explicitly explained in the blueprints. Over time it became more comfortable to improvise.

Obscure observations that came up while building the hovercraft.

The lift duct was particularly difficult because precision was important. The tips of the lift duct propellers needed to clear the lift duct by a few millimeters. To do this the lift duct had to be a near perfect circle. The lift duct started as a piece of ply wood, two feed wide, that was bent to form a circular tube. Making that tube a near perfect circle required a lot of trial and error. The lift propeller spun at a high RPM so any contact between the propeller and lift duct would have been catastrophic.
Faith in the blueprints solved many problems. The propellers were a good example of this. Making propellers out of wood blocks did not make much sense at first but the directions were good enough to overcome my doubts.
Deviating from the blueprints was ok. Situations did arise where the blueprints did not have answers and it was ok to create our own solutions.
Bigger is better. The engines used in this hovercraft were near the top of the allowable limits. Were I to do this again then I would have tried to use the biggest engines possible.
Lastly, building the hovercraft was more fun than driving the hovercraft. It’s a douche thing to say the journey is more important than the destination, particularly if it is said to calm someone that is frustrated, but it’s true. Once the hovercraft was built we could take it out at will but we could never go back and rebuild it. Building it was a experience that we couldn’t relive even if we wanted to.

Observations that came up while driving the hovercraft.

It is like driving a car on ice.
It is very noisy.
It is very dirty.
Water can be treated like solid ground.
You must anticipate any change in motion, turning or stopping well in advance.
The use of hovercrafts in public is a gray issue where Park Rangers don’t mind and others mind a lot.

Ruppert, Daryl & myself looking through blueprints. The blueprints just came in the mail and it was at this point we had to come up with a materials list.

Frame construction was a gradual process. Over time pieces of wood became a rib, several ribs became a cage, and a framed cage became a hovercraft.

The lift duct construction was one of the more challenging aspects of this project. Precision was paramount.

The propellers began as blocks of wood that were glued together then shaped. It was a time consuming process. The propellers were ultimately covered in fiberglass to reduce wear and tear. However each hour of operation probably required a fresh coat or two of fiberglass.

Here is the boat trailer that would eventually become the hovercraft trailer.

The rudders were made from foam, wood and fiberglass. A heated electrical wire was used to shape the foam. After some shaping, fiberglass was added for strength.

Sending the hovercraft off for paint

Putting the rudders and thrust duct together

It was at this moment we were able to test the hovercraft for the first time. We pushed it around the driveway to make sure it could float

Adding the thrust motor

A local TV film crew saw us riding the hovercraft then did a segment on us.

Here is Daryl driving the hovercraft at a local lake

The Newspress did an article on the hovercraft.

Finally, here are some log entries for those times where the hovercraft was taken out.

Location	Description
San Marcos High School	Very first trial and the thing worked. We were running out of daylight and needed someplace to test out both engines simultaneously so we set up in the parking lot of the high school across the street. We did not have a throttle for the thrust yet so one person steered while the other pulled the bicycle cable that controlled the thrust engine. We were all shocked to see it hover and accelerate for the first time. It moved over speed bumps and those cement blocks in front of parking spaces like they were not even there. We also decided that braking is definitely a very significant issue so engine cutoff switches will be needed. We kicked up a lot of gravel and dirt. Dirt gets everywhere, inside the craft your hair, ears, everywhere. The key here is to find surfaces that do not have as much gravel.
Storke Field	The Santa Barbara Newspress came out to do an article. UCSB was on spring break so we decided to try out Stork Field by Harder Stadium. The craft moved sluggishly on grass. On grass air may be leaking through the blades of grass. We all took turns, including Rupert, Daryl, the reporter, cameraman, and myself. The article can be found here, Page 1 and Page 2.
Storke Field	Telemundo Channel 47 contacted us on doing an article for their news channel. We went out to Storke Field again. The guy on the tractor cutting the field was nice enough to stand by for a few minutes. The hovercraft moves at maybe 25mph on this grass. The news segment appeared on TV in Spanish, I need to digitize it or get a translator. The camera man didn’t speak English very well but that was cool because driving the hovercraft is pretty simple when there’s nothing to run into.
Lake Cachuma	We arrived at Lake Cachuma on April Fools day of all days and were not let in the park. That day we were told that the craft “had to be certified by the Coast Guard to enter the park.” So the parks people cried about Lake Cachuma being unsafe if people touch the water. But the craft does have a CF number and HIN(kinda like a VIN for your car) from the DMV. I went through the laws put up by the Coast Guard and confirmed over many phone calls that our hovercraft does meet all boating regulations. What could be safer for a lake then something that does floats on water? So Lake Cachuma would not let us on the reservoir because the bass fisherman were jealous that they didn’t have such a cool boat. Actually County Parks rule 2687c states something like to operate on a lake the craft must be determined to be of standard design as determined by the director or a deputy for canoes, kayaks, rafts, and/or inflatables. In a nut shell anybody dressed up in a funny hat can do whatever they want. We all disagree with this. So we took off to Storke Field again. Jeremy, Daryl & I set up a slalom course – no problem at low speeds. Then we decided to try it for the first time at the beach. We launched at Goleta Beach and everything looked great. But as we got close the salt water, the engines cut out. Salt water is more conductive than fresh water and we now know that the salt water shorted out the electrical system in both engines.
Goleta Beach	We tested the engine by dousing it with water then spraying the engines with salt water. So we went off to the beach with high hopes. We encountered the same problems with salt water as the day before. However the problems were less severe as we encapsulated the spark plugs in thicker rubber boots. It was a bit embarrassing to draw a crowd then get it stuck in water and take 10 minutes yanking cords to restart the engines.
Goleta Beach	The craft now works fine over salt water. We insulated all electrical contacts with silicon gel. It was a bit nerve racking to see it hover for the first time over the ocean but it never cut out. I learned how not to maneuver the craft by trying to drive through an inlet and running into the cliff. A hole was punctured into the bottom of the craft. It is now repaired to where that part of the hull is a bit stronger. We let some random UCSB engineering student try it out then Daryl took out a guy with his 9-year old son. He then emailed Daryl to say that his 9-year old son has been putting lego hovercrafts together ever since that day.
Goleta Beach	Had a nice day at the beach for a few hours. We gave rides to a lot of friends in the Henchmyn band. Unfortunately some student drivers got a little too close to the beach goers and a county parks guy was there to tell us to take the hovercraft home. That and Daryl scaring several hundred birds in the air ruined our welcome. It is pretty amazing every time the hovercraft goes from land to water – almost like watching someone walk on water.
Goleta Beach	KEYT Channel 3 came out to film us at the beach. We got it running on a foggy day with low tide. It runs very fast on wet sand. Daryl was driving pretty fast along the wet sand and thought he could make it between the columns of the Goleta Pier. Well it was great for the camera up to the point where Daryl decided that wasn’t a good idea and turned around. But the craft was moving too fast and did not slow down in time before bumping into the pier. And once again the County Parks guy was there to advise us to get insurance before returning. The incident with the pier scratched up the lift prop and the lift engine mount. The lesson here is to be more careful when on smooth surfaces.

Ashley Madison Statistics

21st August, 2015 · iblaine · Leave a comment

The average age for users is 37. That seems surprisingly low.
Users are more likely to create an account on a date near their birthday but not on their birthday.
User profile captions are pretty funny.

The average age for an Ashley Madison user is 37. That’s surprising given Ashley Madison has been around since 2001. Also interesting is the high number of members aged 38 and 51. My guess is those are fake accounts. There are 34 million accounts and some analysis puts the number of legit accounts at ~800,000.

Here are the some popular profile captions.

Here’s a graph showing that users are more likely to create an account on a date near their birthday but not on their birthday…interesting…

Also, in a hypothetical situation where I had the Ashley Madison data, I would probably do something like this…

Spin up a cheap Amazon cluster and upload data to the new instance.
Write a script to convert a MySQL table dump to a tsv file.
Spin up a cheap Redshift cluster and import tsv files.

Point being the Ashley Madison data is delivered as large MySQL dump files and loading large MySQL dump files is a chore. You would be better off converting the MySQL dump files into a more flexible format like tab delimited files then using Redshift or Hadoop.

The Walking Bike is Finished!

31st July, 2015 · iblaine · Leave a comment

Part 1: Building a Walking Bike / StrandBeest Bike

Part 2: Leg construction for the Strandbeest Bike

Part 3: Frame construction for the Walking Bike

Part 4: The Walking Bike is Finished!

The Strandbeest Bike has been completed, finally. Here is its final form as well as some videos of the assembly. I’ll follow up later with info about the bearings, crankshaft and other construction that I missed in previous posts…