Thursday, March 26, 2009

Wait Until The Last Possible Moment

Here is some good system level advice as it pertains to electronic engineering. I think it is true of other branches of engineering as well.
System-level design is all about thinking early and implementing later. So why not apply what we already know? We even have statistics. Fifteen years ago, I was part of projects where we measured how effective methods like manual code inspection were in preventing bugs from propagating into the next project phase.

Everybody seems to know and agree that it becomes more difficult to find and fix defects the further a project has progressed. More recently, studies sponsored by NASA show that an embedded software bug introduced in the requirements phase is 130 times more expensive to fix during integration and 368 times more expensive after rollout of the embedded device.
So what do you do? Prototypes for one. And not just hardware. Software too. Sometimes it is only in the process of implementing a solution that you come up with a better idea. How do you make sure that idea does not wind up on the drafting room floor? Delay the decision to commit big resources to the last possible moment. Which means a manager must not only be a master of technology. The manager must also be a master of logistics and the PERT Chart.

You also have to recognize the pressures to decide quickly: top management asks, "what is your plan?" and you have to say "I don't have one yet, I'm looking at the options." It requires a lot of trust. And a lot of program time discipline when it comes to execution because you will be using a lot of your project time margin to make sure you get it right the first time.

Wednesday, March 4, 2009

A Big Motor For The Electric Navy

Here is something I should have posted here a while ago.

Superconducting Motor

Last week I did a post on the the science of electric motors that featured a learning kit for kids that provided the parts required for a kid (of any age) interested in the science and technology of electric motors to build a small one. I'd estimate that the motor, which you could hold in in the palm of your hand, produced less than 1/1,000th of a horsepower. Here is a motor whose power is about ten orders of magnitude bigger. And that is a whole lot bigger.

The Next Big Future reports on the really big motor that uses high temperature superconductors.
American Superconductor Corporation, a leading energy technologies company, and Northrop Grumman Corporation announced today at the Surface Navy Association’s 21st National Symposium the successful completion of full-power testing of the world’s first 36.5 megawatt (49,000 horsepower) high temperature superconductor (HTS) ship propulsion motor at the U.S. Navy’s Integrated Power System Land-Based Test Site in Philadelphia. This is the first successful full-power test of an electric propulsion motor sized for a large Navy combatant and, at 36.5 megawatts, doubled the Navy’s power rating test record.
The Business Wire tells a little more of the story.
This system was designed and built under a contract from the Office of Naval Research to demonstrate the efficacy of HTS motors as the primary propulsion technology for future Navy all-electric ships and submarines. Naval Sea Systems Command (NAVSEA) funded and led the successful testing of the motor.

Incorporating coils of HTS wire that are able to carry 150 times the power of similar-sized copper wire, the motor is less than half the size of conventional motors used on the first two DDG-1000 hulls and will reduce ship weight by nearly 200 metric tons. It will help make new ships more fuel-efficient and free up space for additional warfighting capability.

“The successful load test of our HTS motor marks the beginning of a new era in ship propulsion technology,” said Dan McGahn, senior vice president and general manager of AMSC Superconductors. “This motor provides the U.S. Navy with a truly transformational capability relative to size, stealth, endurance and survivability, providing our Navy with a clear performance advantage for years to come. We are grateful for the steadfast support from the Office of Naval Research, Naval Sea Systems Command and the Naval Surface Warfare Center.”
A different branch of the Navy, Naval Air Warfare Center Weapons Division, is funding work that may lead to a shipborne fusion power reactor. Which would be kinda handy to have to power two or four of those electric motors turning the screws of an aircraft carrier. You can read about the latest contract for development of the Bussard Naval Fusion Reactor at IEC Fusion Technology.

And that is not the only electric propulsion system that future aircraft carriers will use. There is also the electric catapult being developed by General Atomics (GA).
GA and its Team have completed the Program Definition and Risk Reduction (PDRR) phase of the Navy's electromagnetic aircraft launch system (EMALS) program and have been selected to perform the System Development and Demonstration phase. The goal of the EMALS SDD phase is to develop the existing design chosen during PDRR into an integrated shipboard system that is both operationally suitable and effective, thus replacing steam catapults with an electric system that will reduce maintenance and provide flexibility and growth potential for carrier aviation throughout the 21st century.The GA Team EMALS design is a robust, highly reliable launch system that will meet or exceed all Navy performance goals. This design will provide significant reductions in installed weight, volume, and workload compared to the existing steam catapult. The design uses state-of-the-art technologies that we believe will demonstrate our system is affordable and producible.
There are more details at the link.

And guess what else the US Navy is working on? A real honest to God beam weapon. The Free Electron Laser
The Navy is pushing ahead with a five-year, $163 million dollar plan to bring the "Holy Grail" of energy weapons up to battlefield strength.

For decades, scientists have been slowly working on a laser that never runs out of shots -- and can be "tuned" to blast through the air, at just the right wavelength. For most of that time, all they could get was a laser at lightbulb-strength. But in 2004, researchers at the Thomas Jefferson National Accelerator Facility finally managed to assemble a "Free Electron Laser," or FEL, that could generate 10,000 watts of power. Now, the Navy has started an effort to design and build a new FEL, 10 times as strong. That would bring the laser up to 100 kilowatts -- what's considered the minimum threshold for weapons-grade. But it would also be just a stepping stone, on the way to an energy weapon as powerful as any produced. If ray gun researchers can get the thing to work, that is.
And lest we leave out projectile weapons how about an offshoot of the electric aircraft catapult. The rail gun which fires projectiles with electricity at a muzzle velocity of better than 8,000 ft per second.
The Navy is researching rail guns because they would weigh less than conventional ones, and since they rely on electromagnetics to fire rounds, you wouldn't need a big, dangerous pile of explosives stored in a magazine. All of that means a lighter ship, and a much more deadly ship: a combat-ready rail gun would be able to fire Mach 5 projectiles over 200 miles with pinpoint accuracy, hitting 5 meter targets.

Yesterday's test firing at the Naval Surface Warfare Center Dahlgren Division used just some of the potential 32-megajoules the laboratory test gun is capable of, and that's only half the 64-megajoules the Navy is aiming at for the final weapon.
If you follow the link you can watch some really cool videos.

It looks like the US Navy has a plan. And you know? I just love it when a plan comes together.

H/T just_an_observer at Talk Polywell