Posts Tagged ‘aerospace engineer’

Commemorating a Special Day – Apollo 11

Friday, July 20th, 2012
Upshot of the Apollo 11 Lunar Excursion Module, the Eagle

History and Heroism Infuse the Apollo 11 Lunar Landing!

A Day to Remember!

July 20th 1969 was a special day for this future Aerospace Engineer, in more ways than one. While not aware at the time that was to be my profession, I was a totally engrossed in America’s space program. And so, despite ample distractions, which I will describe later, I found myself planted in front of the television set on that muggy mid-summer evening. I watched history unfold, and heroism manifest, as it was captured and conveyed back to Earth; grainy chunks of rasterized black, white and gray imagery on that screen – breathless.

That was the day that man landed on the moon.

Visionary and Powerful Leadership

It was the crowning event of the American quest set in motion by President Kennedy during his special address to Congress in which he said that “…this nation should commit itself to achieving the goal, before the decade is out, of landing a man on the moon and returning him safely to the earth.” Beautiful, inspirational leadership, and a simple yet elegant system specification as well. To read the entire speech is to witness the power of effective leadership, meted out respectfully mindful of the balance of powers between our three branches of government. A balance of power, and relationships between the branches as established and constrained by our US Constitution. The mission to the moon, and the occasion of this speech, were not for mere pyrotechnic display, or theater, respectively. On the contrary, the President was asking for resources from the Congress in the name of national security. Kennedy cited the extreme stresses of the time, in the midst of the Cold War, and recognizing the on-going struggle between freedom and tyranny taking place on the world stage.

Failed Leadership and Floundering

Kennedy’s strength at the time saddens me, now when considering in contrast, the profound weakness of our current president. Bowing as he does before world leaders, apologizing for, and denying American exceptionalism, abandoning our allies, and decimating our current space program to the point of shambles – we now rely on Russian transport to ferry our astronauts to and from the International Space Station. Pitiful.

Heroism Manifest

As for heroism though, I am continually inspired by that of Neil Armstrong, Buzz Aldrin and Michael Collins – the crew of Apollo 11. To me this is the height of human achievement, exemplary performance under pressure, and a testament to the quality of the human spirit. A spirit which is capable to aspire to, and to accomplish great things. At the bottom of this post I have embedded an annotated video clip of the final 13 of descent and landing on the moon. Armstrong, Aldrin and Mission Control acting in perfect coordination. This is heroism exemplified – Armstrong at the control, Aldrin as co-pilot monitoring systems, and Mission Control coolly and professionally executed mission operations per procedure.

Using computer systems that would be dwarfed in comparison to even the simplest mobile phones of today, they prevailed. The entire video transfixes me, but in particular the last three minutes are absolutely riveting. As Armstrong assesses the suitability of the landing zone he in fact has to make manual flight adjustments to avoid boulder fields. Meanwhile Aldrin is calmly reporting systems status – with master alarms going off, no less! The guidance system was being overloaded, but because of robust software design the descent could continue. Regardless, dealing with master alarms in the final seconds of the landing on man’s greatest adventure to date had to be unnerving – still they steadied on. When they landed the Eagle Lunar Module had less than 25 seconds of fuel remaining. Incredible!

Landing, and then the words: “Houston, Tranquility Base here. The Eagle has landed.”

A Special Gift for a delighted Birthday Boy

As for my other distractions; that day also happened to an anniversary of my own birthday – no need to tell you which anniversary, we’ll let that be a mystery. I am not sure where I stand on the concept of destiny – I don’t actually think that being born on a day that later would also be the day of the first moon landing made me be an aerospace engineer. How I became that is a story for another day.

I can’t deny though, the power of inspiration that I draw from this. Coincidences like this could have had an influence on such choices. But all of that speculation aside I do know that year after year it makes my birthday feel all that more special to me. Not only can I celebrate life, but I can share remembrance of a moment steeped in history and heroism – a moment in time when, as a result of strong vision and leadership, and of near perfect human execution, a great thing was accomplished!

Watch the video here; embedded link provided for your viewing and your appreciation, the annotated video of the Apollo 11 descent and landing:

In addition, the wikipedia entry for this mission is also very interesting.

I find this event inspirational; how does it affect you?

Good News/Bad News in Space

Wednesday, July 18th, 2012

Good News – NASA’s Next Generation Crew Vehicle is in Testing!

Good News, Bad News, in Space?

While starting to research a post lamenting the sad state of affairs with regard to US Manned Spaceflight I stumbled upon a bit of good news. So instead of a standalone bad news post, this turned into a good news/bad news post. Let’s start with the bad news, to get it out of the way.

US Needs Russia for Transport to ISS

Since the demise of the US Space Shuttle program, the United States has relied on the Russians to provide transportation of our astronauts to and from the International Space Station. The latest trip is ferried our Sunita Williams as a result of a successful docking of the Soyuz capsule with the ISS as reported by Fox News.

As a child of the space age, I grew up in an era when American exceptionalism, including, if not led by our accomplishments is space, was embraced and celebrated. Not so much now, when in America, starting with the office of president our past accomplishments almost seem a source of shame, and are downplayed and even used as cause for apology to the world. Regardless it galls me that we find ourselves as a space-faring nation having to depend on the Russians for transport.

I guess it could be worse; I suppose that absent a Russian program we could enlist the services of the Chinese? How does that sound to you?

Good News – Orion is in the Pipeline

In contrast with that gloomy outlook, witness the other side of the coin – progress is being made on the Orion program. According to the story on NASA’s website:

“A C-17 plane dropped a test version of Orion from an altitude of 25,000 feet above the U.S. Army Yuma Proving Ground in southwestern Arizona. This test was the second to use an Orion craft that mimics the full size and shape of the spacecraft. Orion’s drogue chutes were deployed between 15,000 feet and 20,000 feet, followed by the pilot parachutes, which deployed the main landing parachutes. Orion descended about 25 feet per second, well below its maximum designed touchdown speed, when it landed on the desert floor.”

Despite our current dependence for astronautic ferrying, developments in the Orion program are hopeful signs that US standing in space will improve. Whether such progress will be sufficient to keep pace with other nations who are advancing in space, such as the Chinese in particular is up for debate.

Given how important space capabilities are to our national defense, I remain skeptical as to its sufficiency; what do you think?

Building 6

Tuesday, July 10th, 2012

Big building, where the shuttle was built

I could not have imagined a more ideal first job out of college for a young aerospace engineer. The Space Shuttle was still young, new and exciting. It had only launched three times when I had arrived for my first day of work in Building 6 of the Rockwell International plant in Downey, California. The front of the massive building was an impressive sight facing Lakewood Boulevard. Major sub-assemblies were being built in that factory – during my tour of the plant on that first day I was walking among the cockpit/crew station structure in their various states of emergence. The space program still captured attention – each mission was being followed closely.

It was odd that on my very first day I felt both young and old at the same time. Old in that, now well past high school age, I was now a college graduate starting a real career in the aerospace industry. Young on the other hand in that I was the most junior person in the First Stage Ascent, Guidance, Navigation and Control group. As we posed for our group picture, which was coincidentally being taken on my first day, I was surrounded by engineering veterans, most of whom had built their career during the Apollo era. I remember being stunned that some of there faces seemed familiar as fixtures in the behind-the-scenes footage shown in various Apollo era mission control room newsreel footage. White shirts, thin ties, pocket protectors abounded; not cliches, but real – this was the fashion of the day. I may have been the youngest new recruit, but that would change, and soon others would be added.

Space still mattered, and its workforce was growing, and it would continue to grow – at least for a time.

Rockwell International as a corporate entity is long since gone, having been bought by Boeing in the late 1990’s, but Building 6 still remains. Supporting just a fraction of the number of jobs, the site now hosts a film production company that you’ve never heard of before. Turns out buildings like this now retain value, not as monuments and museums to a once proud US space program, but as backdrop for Hollywood. Old plants such as this shuttle factory are ideal for filming when the director needs a dilapidated industrial setting.

So not surprisingly, in a region famous for film, Southern California once again has more of future in entertainment, than in space.

Continuum

Monday, July 9th, 2012
a diagram to illustrate the concept of a continuum

Continuums are Cool!

It is always good to know where you are. This knowledge provides context which can help you make good decisions. It can also help you predict how your environment might affect you physically. This is true in life, in general, but it is also true in science. As an aerospace engineer I am interested in the science of aerodynamics, where environmental context is critically important.

Environment is so important in aerodynamics because aerospace vehicles behave differently depending on where they are. Clearly an airplane and an earth-orbiting satellite operate in different regimes. One way to distinguish flight regimes is determine whether there exists a continuum.

According to wiktionary a continuum is defined as “a continuous series, or whole, no part of which is noticeably different from its adjacent parts, although the ends or extremes of it are very different from each other.”

In practical terms earth’s atmosphere is a continuum. The air is composed of many molecular particles that interact with one another. At sea level these particles are very close and densely packed. High in the atmosphere though, the particles are much less densely packed and are farther apart from one another.

The average distance between particles is called the mean free path. Gravity affects these particles and tends to pull them down to the surface, so they collect densely at sea level and the mean free path is short. With increasing altitude the mean free path increases, for a variety of reasons. Mean free path is one of two important paramters need to the define a continuum.

To discuss the second parameter I need to establish the idea of a simple airplane. The simplest airplane I can think of is a flying disk, so, imagine a frisbee. The diameter of the frisbee is the same as its chord length.For a traditional wing the chord length is the front-to-back distance from its leading edge to its trailing edge. Chord length is the second parameter needed to define continuum.

For the purposes of aerodynamics there is a continuum when the mean free path of the surrounding atmosphere is shorter than the chord length of a object under consideration, in this case, our frisbee.

Once the mean free path exceeds the chord length then there is no continuum anymore. In effect the regime is no longer atmospheric, but rather, space. The physical changes from sea level to the boundary of space are gradual; beyond that boundary the change transitioning to space is abrupt, and calls for a different type of design for any vehicle.

I find this concept compelling for its similarity to other things in life. The ageing process – a continuum. The way we learn – a continuum. Our position in life changes more often like a continuum rather than abruptly. There are many others.

Not all things in life, but many, we experience as a continuum.

I am often amazed at how the things I learned in becoming an engineer have relevance outside of their strict application in science.

 

 

Best Robotic Legs Ever?

Friday, July 6th, 2012

A very interesting development has been reported by the Daily Disruption News Desk regarding robotic legs that are claimed to “fully model walking in a biologically accurate manner.” This will come as good news for spinal cord injury patients. Those of us who follow developments in artificial intelligence and robotics will likely take note as well.

I read this account with fascination, and immediately wanted to sketch out my understanding in model form. Extending the colloquialism, to a hammer, everything is a nail – to a systems engineer, everything must be modeled. As conveyed in the article, human walking is controlled by a neural network called the central pattern generator (CPG), which is anatomically located in the lumbar region. It’s purpose is to generate rhythmic muscle signals. The researchers said in its simplest form the CPG can be modeled by a neuron pair that each fire signals in alternating fashion.

To complete this model in addition to the neural architecture, the robot needs muscle-skeleton and sensory feedback components. Roughly, this system can be modeled as shown:

I could be wrong, but this is how I understand the Robotic Leg System!

Co-author of the study Dr Theresa Klein was quoted as saying “…we were able to produce a walking gait, without balance, which mimicked human walking with only a simple half-centre controlling the hips and a set of reflex responses controlling the lower limb.”

So, did you catch that? That was quite a surprising statement. Two things are totally counter intuitive to me. First, she said the robot works “without balance.” Does that mean that this robot does not need an “inner ear” to balance? Second, the CPG apparently apparently converts coarse motor commands into forces applied at the hip joint only. The “dangling part of the leg, the lower limb, just follows reflexively, implementing easily programmable commands that simple follow what is happening up stream at the hip.

Another implication of this analysis is that the brain proper plays less of a role in controlling gait that I would have guessed.

This would be a good time to confess that I could be totally wrong in my interpretation of this research and its result; I am learning as I go.

Speaking of which, the CPG model of this study is apparently a good facsimile of how gait is refined from early childhood steps through later improvement during the maturing process. The CPG in humans gets better over time as it learns the best walk to walk by repetition.

This is exciting as I can see similarities between this system and what I am learning in my Udacity.com artificial intelligence class. The evolving understanding of complex bio-mechanical systems as well as advances in AI make this a great time to be a student of such things.

That’s my OODA Loop, and Yes, I am Happy to See You!

Friday, June 22nd, 2012

Having introduced the OODA Loop yesterday it’s now time to examine how its application is relevant in my life currently.

Traditionally associated with military tactics in aerial combat, this recurring decision-making cycle consists of these steps – Observe, Orient, Decide and Act. Information from each step feeds forward into successive steps. Similarly, results of each increment feed back directly to the Observe step since they represent significant changes in the overall situation.

This has proven effective in the stress of combat because correctly applied it allows the pilot to respond effectively to the environment and to his opponent. He will defeat the enemy and perhaps most importantly, he will likely survive the encounter.

While I am not engaged in aerial combat presently, I do find myself in a rather stressful situation. I am currently unemployed; my economic survival and readiness for my future are in question. As such, it occurred to me to revisit the OODA Loop with the following question in mind – could I apply it to my present circumstances?

Here’s what’s going on with my OODA Loop, mid-cycle:

Observe – Relevant aspects of my observable environment include, [1] a US economy in a deep and severe recession, with sparse, if any at all, indications of near-term improvement, [2] an aerospace industry that is stagnant with no major US government acquisitions on the horizon, [3] a personal economy that includes mortgage commitments, and retirement savings which, although “above average” will not be sufficient on their own, especially in light of likely Social Security and Medicare reform.

Without making my age an inordinately large part of this conversation I will say that I am too young to take early retirement, but I’ve been around long enough to become vulnerable in terms of age and wage discrimination in my former industry.

If the preceding observations seems overly negative, I will assert that I do have useful skills accrued over my undergraduate education and professional career. These are reusable skills that can be leveraged and repurposed.

Orient – A large part of my orientation step depends on the quality of, and my interactions with my immediate and extended network, and with friends, one of whom has assisted me in a role as my mentor. The interim result of my orientation step is an awareness that [1] software solutions are ubiquitous with little prospect that software’s role in our lives will diminish, [2] modern personal computers are incredibly capable and can be leveraged to host powerful development environments, [3] the open source software movement has produced vast volumes of free software, [4] delivery systems, most notably cloud-based computing have revolutionized how software can be distributed, [5] the internet itself stores expansive resources to learn many things, including software development, [6] new means of “knowledge delivery” are beginning to emerge, most notably Udacity.com, a free, online university taught by world-class professors, from institutions such as MIT and Stanford. Did I mention it was free, and world-class?

Decide – Based on my observe and orient steps I have decided on this path: I will prepare myself to become a hybrid of a systems engineer and a software developer, by following a jointly determined (by myself and my mentor) learning curriculum, using my “powerful laptop” along with open source software development tools fashioned to implement a linux-python-java-groovy-grails-MySQL ramp in order to develop value-added solutions to customers ranging from small business to large-scale aerospace, delivered whenever possible as a hardware/software appliance bundle, or as software-as-a-service (SaaS).

Act – Based on the above plan I will learn specific software skills through [1] self-directed study using borrowed books and the internet, and through [2] successive classes at Udacity.com. Associated actions, on a parallel path to the software learning include, learning the basics of business, and business development through interaction with my network, and by attendance at various meetups and user’s groups. In addition I will be revisiting selected liberal arts educational objectives that weren’t part of my aerospace engineering eduction.

As a result of actions, taken above, more feedback is directed to the Observe step and the cycle repeats.

Note, to tell this story, it has been streamlined. In reality I have already been doing this over the course of a year. I have been through roughly four complete cycles, and this post represents a distillation. At this point I am effectively entering a new Act step which will include enrollment and completion of several Udacity.com courses for the next hexamester that starts Monday the 26th of June. Having completed Dr Peter Norvig’s most recent class, cs212, the Design of Computer Programs I have Observed, Oriented, and then I Decided on the next classes. Note that the classes I will take are different than what I might have expected to take prior to the last cycle through the OODA Loop.

This is an experiment-in-progress, but so far, I’d say it has been effective for me. In my opinion it is a flexible, agile approach. With current economic stresses and uncertainties, combined with concerns over the long term prospects for traditional employment models in corporate America, I believe that this kind of method is as applicable, now, to people in my situation, as it was when first formulated by John Boyd for application to aerial combat.

Is there an OODA Loop in your Future?

Thursday, June 21st, 2012

Being out and about in today's dismal economyJohn Boyd’s OODA Loop as Data Flow Diagram by Michael LaRue presents an array of opportunities and challenges. Since the word displaced is a euphemism for laid-off/unemployed, let's face it, restoring an income stream is one of the most important of those challenges. One way or another, doing that will require some situational assessment and decision-making.

Regardless of how well an aerospace engineering degree and decades of professional experience may equip a person, there is no silver bullet solution, or natural growth path towards a comfortable future, once displaced. A person in this position has to be resourceful and purposeful in moving forward.

Presented with this exact situation myself, I wondered what decision-making framework from my prior experience might serve well? Fortunately for me, something came to mind pretty quickly, the famous OODA loop!

My exposure to this concept came while working on an enhanced threat assessment feature of the Space-Based Space Surveillance system. Don't worry, it's unclassified, or at least it was at the time.

Briefly, OODA is a method for effective decision-making which is composed of a recurring cycle of the following steps: Observe – Orient – Decide – Act. This loop was created by Air Force Colonel John Boyd for application to military tactics in aerial combat. To paraphrase, the objective is to defeat an enemy in combat, and survive, by operating at a tempo faster than their ability to effectively make their own decisions. An excellent introduction to the subject can be found within this wikipedia entry.

For a person in my position, this seems like useful strategy to employ. If you are in a similar situation and don't think it's good, then perhaps you married rich, are already otherwise financially independent, or you've got a better idea yourself. If that's the case I'd love to hear from you; let me in on your secret, please!

To illustrate the OODA Loop I've created a Data Flow Diagram. This is a notation by Tom DeMarco in his excellent book, Structured Analysis and System Specification. I've used this notation frequently, to great effect in my aerospace engineering days. Most other times I've seen it presented though, it's been in a classical flowchart style. Rather than just regurgitate that form, I thought a fresh look might be helpful.

In my next post I will outline how I've applied, and will continue to apply, this approach, to the ongoing process of recreating myself for my future.

Until then, if you've lacking for something constructive to do, at least start doing the first of the two O's – start observing your environment and your circumstances. What could be more important that being aware of where you're at?