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Comment Industrial engines (Score 1) 543

Don't discount industrial engines. While automotive diesels are designed to operate at a wide range of RPMs, industrial engines are typically designed for a fixed speed purpose, such as powering a water pump to lift water from one canal to another for irrigation, or powering a generator, etc. An engine like this with a well tuned intake and exhaust can be extremely efficient and extremely quiet.
Google "Helmholtz Resonator Principle" for designing the intake and exhaust properly.

One that pops immediately to mind is a lightweight, but very torquey 3-cylinder Kubota Diesel engine, such as that used in the Urba-Centurion (128mpg DIY Diesel sports-car designed by Mechanix Illustrated back in the early '80s).
If that one isn't powerful enough, the company makes a wide range of similar engines.

Alternatively, try and find a wrecked VW TDI with a good powerplant, like the one the West Philadelphia high school students used to make a hybrid sports-car (K1 Attack, 0-60 in 4 seconds while burning 50mpg!)

As I suggested in a previous post (not sure if you read them all), please post in evalbum.com, as I'd love to watch your progress! :^)

Comment Kokam batteries (Score 1) 543

You should check out Kokam Li-Ion batteries. They've got some pretty impressive tech to improve their charge and discharge rates (you need the latter for high torque impulses required for standing-starts, especially if there are any hills in the area) and "ten-plus years of operational life". Just going to the first vendor that showed up in google, I see they now have a huge range of batteries all the way up to 240AH (@3.7V), so you could give your SUV an incredible range before needing the ICE range-extender.
The nicest thing about these, compared to the typical cylindrical Li-Ion cells that are popular with many of the DIY electric-car crowd, is these are large and rectangular with large tabs for electrodes, which makes them much easier to make carriers and contacts for, not to mention the battery control circuit savings (you'll need less of them if you have fewer/larger batteries).

Comment Go A/C! (Score 1) 543

Circuit Cellar Magazine issue 217 (August 2008) had an article titled Electric Vehicle Inverter Design (Build A System For Powering AC Induction Motors) by Dan Hall, Tristan Kasmer, Doug Krahn, Adam McIntyre, and Dena Ponech.
It should still be available from their website, though I think they charge a couple bucks for it now (it used to be freely downloadable as Kasmer-Krahn-McIntyre-Ponech-217.pdf).

This is a fantastic article discussing many different speed control methods used for A/C motors, and why the authors chose the one they did (very little motor noise and very natural feeling torque control, among other things). The article states "Obtaining a typical three-phase high-power inverter for driving an ACIM can cost between $8,000 and $25,000" then goes on to say "Any technically minded person should be able to complete this project for around $2,500".

While A/C seems odd at first due to losses within the inverter, apparently the increase in efficiency more than makes up for it... not to mention motor availability.
Before anyone replies that DC motors make more power, tell that to Tesla (and AC Propulsion, from whom Tesla licenses the powerplant design and creators of the tzero). ;^)

Good luck with your project, and please post pics and info to evalbum.com! (fantastic source of inspiration and information if you haven't been there)

Comment Personal use license gone? (Score 2) 75

(I just realized I accidentally posted A/C last night... reposting while logged in)

Before they changed the name ("Creo"? Really?) away from the extremely well established Pro/ENGINEER branding, they had a personal use license for $250. I just came up with a use for it (interesting timing for this announcement), and now I don't see this option available.
I did find the student license, but I'm not a student and the requirements are quite clear and specific - and I don't meet them.
I also found the Creo Elements/Direct Modeling Express for free (up to 60 parts, which suits my needs), but this doesn't appear to be the same software. Does anyone know if this still has the "sketcher" to rough draft the profile of the 3D parts? (I'll have to build a MS machine to even test it out - doubt it runs in Wine).

Granted, the last time I used Pro/E was ~1994 (on Solaris) and the UI has changed dramatically at least twice since then, so I'll have to re-learn it anyways.
I actually liked the original UI... when they changed it to meet Microsoft's requirements (when they first offered it on MS windows), I thought it was a horrible turn to an inefficient design. Don't get me wrong, I understand the reasoning (make it "familiar" to windows users), but the change made it much less efficient to use even though the learning curve was shallower.

Yes, I agree with other postings, it's a shame they dropped Linux support.
I just googled "3d cad linux" and the top advertisement is titled "3D CAD Linux - Flexible, Easy-To-Use Application | PTC.com" with a link to www.ptc.com/Free-Download, which leads you to download 2 options, 32bit and 64bit windows software. That's kind of a dirty advert method for a company as well established as PTC...

Comment Re:Including your SSN? (Score 1) 62

You've just described South Florida, and the reason why our car insurance is among the most costly in the nation (we're back and forth at the top over the years with New York and California).

Remember the "don't go to work" protest against the politicians who wanted to round up and deport all illegal aliens back in 2006? (if not, google "Un Dia Sin Inmigrantes") The day collectively called in sick? The freeways during rush hour down here were as empty as 4am on a Sunday!

If it's not obvious, I agree with the person to which I'm replying - Drivers Licenses should be just that, but are instead being used in ways that are detrimental to the original purpose.
Florida has increased the difficulty in getting a driver's license, but not in a way that matters to its purpose. Check out the blue box at the bottom of this page: http://www.flhsmv.gov/html/dlnew.html
Why do I say that it's not a change that matters to its purpose? Because the "driving test" they only put those under 18 though consists of driving through a parking lot! Seriously! (if you're over 18, you don't get tested)
For an eye-opener, google "rudest drivers in America".
I took the test in FL during a summer vacation before I had my MI driver's license... in Michigan, I had to drive though some very confusing and highly congested rush-hour traffic in the middle of Pontiac for my driver's test. Quite a contrast.

A (poorly) trained monkey could get a driver's license in FL, but only if he had enough proof of identity!

Comment One solution was invented decades ago... (Score 1) 117

I can't remember if it was Popular Science, Popular Mechanics or Mechanix Illustrated, but at least 25 years ago I read an article about an invention that would be ideal for such a spill.
It was a large dome that floated mostly underwater, with a cupula sticking out of the top with baffles that directed waves into the center.
The wave action essentially pumped the oil floating on the surface (and water) into the dome, and since the oil floats, the water was pushed out of the bottom. It was designed to be deployed as an array for very large spills such as this one.

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