Water Jouncers

Background

I really have no idea why I thought of this. The kids woke me up early and I couldn't fall back to sleep. While laying in bed this morning I got a bunch of ideas. My brain is a single-thread processor. It's like a railroad track but there are a million switches. I think along one thread, sometimes detouring on tangents, evaluating ideas more deeply or completely switching directions on a new but related thought. I often backtrack and take different switches that I marked as interesting along the way. Conversations are like this. Jenn and I sometimes find it fun to trace conversations backwards and see all the different switch points.

Anyways, I'm sure there was some half-logical track that got me onto running across the water.

The Idea

A stilt contraption that displaces water allowing you to run across a water surface. First solve the mechanics of water displacement and find workable human input scenarios. One possible answer is to displace lager surface area like a lizard. Problem is with retraction speed. Evaluate an artificial webbed foot that expands on contract, putting force into springs. Then upon contraction the springs pull the webbing in and propel the foot out of the hole of displaced water. Or maybe the actual foot never enters the hole. Maybe it's only the mechanical device goes into the pocket, and the springs pull it out again, reset by the force of every step.

Progress

11/27/2014

Lizard that can run on water

Robot that can run on water

Just for Fun:

Fake but Fun

Jeff's Miracle Boots

No-Boat Water Skis

Background

The Aquaskipper has proven that human power can propel a person above the water using hydro foils. People have attempted self-propelled water skis in the past, but the designs were all horrible. The Mythbusters' Adam Savage tried a typical approach of floating pontoons with flaps for propulsion. They turned out to be unstable and not mobile. What we need a good, functional design.

The Idea

I need to sit down and determine the physics required to keep a person on top of the water using a combination of buoyancy and propulsion. Then I need to explore the design space around these two factors and design water skis that operate similar to the principals used in the Aquaskipper. In my mind I envision something like cross-country skis for water. Cross-water skis?

Progress

11/27/2014:

A Purely Buoyant Solution - Archimedes' Principle

Put simply, the buoyant force on a submerged object is equal to the weight of displaced water. For a purely buoyant design this means displacing enough water to hold up a person. Assuming a weight of 80 kg (roughly the average American male) at standard temperature and pressure, this means displacing approximately 80 liters of water. Sounds like a large volume, but that equates to two skis that are 25 cm wide, 10 cm deep and 160 cm long. So I guess Adam Savage had it about right with his big dorky skis (for the record I was rooting FOR him).

In my opinion this is the worst way to design these skis. This is the maximum footprint of a workable design, so we should be able to stay well below that size by requiring the person to move to stay afloat. More like the Auqaskipper which uses little buoyant force.

A Purely Dynamic Solution - Barefoot Skiing

A rule of thumb for barefoot skiing speeds says take your weight in pounds, divide by two and add 20 miles per hour. This gives around 37.5 mph or 60 kph. That's really fast. The Aquaskipper obviously goes much slower than that. I found a paper on water skiing biomechanics that showed a chart of rope load that was half the skier's weight while going 15 kph.

Arduino Decibel Alarm for Noisy Kids

Background

My wife and I are night-owls but our children are early risers. We used to get up with them every morning, but have slowly trained them to do their morning routine by themselves. The only problem with this arrangement is when the kids decide to reenact "Lord of the Flies." They can get very noisy, interrupting my precious sleep. I get really cranky when I haven't had enough sleep. The kids are very responsive when I tell them to be quiet, but they quickly return to their activities and resume their loud volumes before I can drift back to happy land.

If my wife or me sits down with the kids and constantly reminds them to be quiet, then they do pretty well. But then only one of us gets to sleep (usually me). I just wish there was some kind of electronic babysitter that could tend the to the kids' volume during that hour between six and seven in the morning.

The Idea

Use an electret microphone on an Arduino to listen to the kids as they play. When their noise level goes too high then it will trigger a recorded message that will encourage the kids to be quiet.

This could be used in multiple ways. If noise a single, short noise spike is detected (like a shriek) then it could play a nice recording of Dad saying, "Remember to be quiet kiddies." If the volume is steadily rising it could say, "Hey, your getting out of control, time to do something more quiet like reading a book." Finally, if the volume stays steadily loud it could play something truly frightening.

Progress

11/27/2014 - I've got an Arduino, and an SD card kit that can be used to play MP3 files. I just need to find a suitable speaker and microphone. Instead of a speaker I've got an FM transmitter that can be connected to the Arduino and I could turn on the radio to a blank channel. I think a speaker would be easier, and more portable.

Hardware Device to Make a DVD Player Act Like a Hard Drive

Background

I'm always in the pursuit to maximize the utility and convenience of my Home Theater PC (HTPC). For me this means finding a balance between cost, performance, footprint and versatility. I want to be able to play DVDs, watch Netflix, YouTube and possibly even some light gaming. This is all available on a Windows platform, but that comes with the cost of a Windows license and the hardware to keep up with Windows bloat. I've tried Linux, but it just doesn't support Netflix reliably. Android has everything except DVD support. There are some new Android mini PCs that would work great if I could just find a compatible DVD player.

While searching for DVD drives I found other people who want to access DVDs on other devices. It seems that hard drives will work on EVERYTHING...TVs, phones, tablets, computers, etc. Why can't DVDs have the same support?!

The Idea

We could solve everyone's DVD problems by creating a hardware device sits between the DVD player and the computer / TV / android device. The device would read the DVD player but make it look like a hard drive to the computer.

I know that this device is 100% possible. In the worst case scenario the device is a mini computer that plays the DVD and transcodes it into an MPEG file. I guess basically a hardware transcoder. That's not cost effective. To be cost effective it would have to operate on a very low level, reading the DVD to see what options are available, then present them as a limited set of files on a hard drive, each file name representing a different set of movie options.

I think the biggest hurdle is solving the problem at the file transfer level. You have to present files that are readable by the computer, which for really stupid devices means video and audio files. Dumb devices only know how to read different file formats, so how do you convert the request for a byte stream into a DVD read? It may not be possible to get that low. Maybe transcoding is the closest you can get.

Progress

 11/27/14 -I really don't have the background to research this device right now, and I'm not interested in learning that low level programming, so this idea is gonna sit on the shelf, probably forever.

A Study of Adhesion Strength in 3D Printing

Background

I'm having terrible adhesion problems on my new 3D Printer. It's keeping me from making progress on other projects that rely on 3D printed parts. While researching a fix I discovered that this is a universal problem among hobbyists, and everyone has their own solution including glue mixtures, taping schemes, heated beds of varied temperatures, cleaning solutions, various print bed materials, calibration routines, etc. I understand that everyone has a slightly different build, and those builds will add variation. But I think that excuse is over-used because of the lack of usable data. The common theme seems to be people trying one thing after another until they find something that works. Very unscientific.

I really don't want to take a "shotgun" approach to this problem, but I don't really want to use my free time systematically designing and running experiments to collect the necessary scientific data. It would require a force gauge which costs around $100 for a decent unit, and I would rather burn that extra money on something more fun.

As an engineer I get this type of data from companies who are dedicated to performing experiments to collect data on heat capacities, enthalpies, transfer coefficients, etc. etc. etc. We just pay someone else to collect the data. I haven't found an entity in the 3D Printing world that has undertaken the science of all these little problems that hobbyists face.

The Idea

Since I'm losing my job in June 2015 I'll have some free time. I could probably dedicate myself to a systematic study of 3D Printing problems. I'd design and perform experiments on print adhesion using different substrates, temperatures, filaments, surface treatments, etc. Then I could publish and hopefully sell the information to pay for my time and the capitol required to perform the studies.

My big concern is how to distribute the content in a manner that will help pay for the time and capitol invested into the project. I'm a big believer in publishing this stuff for free, but there's so much work to be done I don't think I could afford to go unpaid for that long. Maybe I could get funding up front via KickStarter so I can reduce the risk of recovering a personal investment. That would also help reduce the risk of people just copying and redistributing the content. If it was paid for up front then I could just post the results for free. Otherwise I'd have to look into a distribution method to protect the copyright, like a website or cell phone app.

Progress

 11/10/14 - Just an idea so far. How do I gauge the potential interest from the community?