Sunday, June 30, 2019

Tribute to Apollo Program in Houston

As part of the celebration of  the 50 year anniversary Apollo 11, the zenith of the agency's existence, NASA's historic Apollo Mission Operations Control Room 2 ("MOCR 2" - pronounced "mo'-ker") is set to reopen to the public next week.  Viewing (from the visitor's gallery, via tram tours departing from Space Center Houston) starts tomorrow, July 1, 2019.   If you're in the area, or don't consider it a big deal to go, it's probably worth your time. 

Ars Technica has the story.
For the past two years, historians and engineers from the Kansas Cosmosphere's Spaceworks team have been lovingly restoring and detailing the 1,200-pound (544kg) historic sage green Ford-Philco consoles that populated the control room—repairing damage from decades of casual neglect and also adding in the correct control panels so that each console now correctly mirrors how it would have been configured for an Apollo flight.

Ars was invited to view the restored MOCR 2 last week as the final finishing restoration touches were still being applied. We conducted some interviews and shot some photos while technicians and construction workers bustled around us, hammering and screwing the last bits and bobs into place. The room's lighting system was in the process of being worked on, and the room flickered several times between fully illuminated daytime lighting and dim twilight—providing an even more accurate glimpse of what it might have looked like during an actual mission.
MOCR 2 was where controllers sat and ran every Apollo flight except for Apollo 7. "The Eagle has landed" and "Houston, we've had a problem" both happened in MOCR 2.  It's not quite that simple, though.  Apollo flights lasted from 1968 through the end of 1972, and the room changed over those years.  Naturally, NASA wanted it to be exactly like it was at its best and most capable. 
To start with, each console has been rebuilt to resemble its Apollo 15 configuration, down to, in many cases, even having period-correct labels on individual panels and buttons. The MOCR changed a bit in between flights, and NASA chose to go with an Apollo 15 configuration rather than an Apollo 11 configuration for a couple of reasons—the first and most important is that there's a large amount of Apollo 15 documentation readily available, including a complete MCC configuration guide that details all the panels and button layouts (documentation for earlier mission configurations is more difficult to come by).

Further, Apollos 15, 16, and 17 were "J" missions, which were the most complex of all the Apollo flights. Configuring the room Apollo 15-style meant having the most stuff on display and provided the best showcase of MOCR 2's capabilities and design.

The consoles are beautifully done, rigged up for the first time in decades with functioning lighting and screens. Tetley explained that rather than reconnecting the buttons' built-in lighting, technicians had painstakingly wired new LEDs inside each individual button so that their lighting could be managed by a central Crestron automation controller. The screens themselves are LCDs dressed with a new fascia, though the original tube displays have been saved and preserved elsewhere. While we were taking pictures, the screens mostly showed off the same handful of Apollo-era displays (which were all dead-on accurate, even down to the typeface). Tetley explained that during an actual tour, the console screens will run through preprogrammed sequences of static images and video.
In any sort of reenactment, the difference between great and "also ran" is the level of details.  Workers found scraps of original carpet and wallpaper that weren't faded or degraded over time, but that aren't available today.  The carpet was recreated by a different company.  The supplier of the wallpaper was bought up by another company in the intervening years.  "But they went to that company," she continued, "and they found the roller in their warehouse." With a bit of retooling, the company was able to churn out a custom order of new vintage wallpaper for the room. "This is an exact copy of the wallpaper that we have."

But that isn't the most extreme portion of the work.
Perhaps the most bonkers bit of restoration has to do with the ashtrays that decorate the consoles, exactly as they did in the '60s. They were empty when we did our photo shoot, but the restoration team has plans for those, as well. "We're going to have cigarettes, cigarette butts," she said, laughing. "All the cigarette butts that were found when they cleaned the consoles and when they cleaned under the floor, we saved all those. I have people smoking cigars and they have to lay them out so they don't stink. So those'll be put back in."

That commitment to authenticity extended even to the dressings applied to the consoles, which are each festooned with three-ring binders (empty when we took our pictures but set to be stuffed full of correct and accurate mission logs and procedures before the room reopens), ashtrays, mugs, thermoses, empty cigarette cartons, and soda cans. Tetley and team even located the correct brands of tobacco products for each of the controllers—Ars reached out in email to former EECOM controller Sy Liebergot about the can of tobacco on the EECOM console and whether it belonged to him or his counterpart John Aaron, and we got a fast response: "The can of Mac Baren's burley is pipe tobacco," he replied. "So it was probably mine since John smoked cigarettes."
People who don't follow the space program are probably not aware that the Johnson Space Flight Center in Houston is strictly the result of Lyndon Johnson's work in the Senate; truly an act of "bringing home the bacon" to his constituency in Texas.  Originally, flight control was from Cape Canaveral (before the assassination of JFK).  When the new Flight Center in Houston was constructed, control was on the Cape until liftoff, when authority transferred to Houston.  As a result, there are virtually identical consoles and other electronics at the Kennedy Space Center, inside the Vehicle Assembly Building. 

I think the restored MOCR 2 exhibit would be an interesting thing to see.  Houston is pretty much a two day drive from here - the mapping programs tell me it's 18-1/2 hours with good traffic.  A bit far for me to drop in.  As I said in the lead in, if you're in Texas, or it's within your easy, "let's go see it" distance, it seems like it would be worth seeing. 

(Standing at the top row of the MOCR looking forward. The consoles are all lit via internal LEDs powered by a Crestron commercial lighting system, and the positions are all dressed to appear as if the controllers had all gotten up mid-shift and walked out and left all their stuff behind. )

Saturday, June 29, 2019

Saying Goodbye to Pride Month

I think these will be the first words I've ever written about pride month.  For a simple reason: I don't believe in their premise.  According to National Today website (a place that lists all of those "today is National whatever day" holidays):
June is Pride Month, a month to celebrate gay, lesbian, bisexual, transgender, queer, and asexual people, plus all other sexual orientations and genders. 
So pardon me if I don't play along. 

My definition of pride doesn't include sexual orientation in any way whatsoever.  Pride is for things an individual has accomplished.  Pride doesn't extend to nationality, race, or anything a person has no control over (which clearly includes any of those sexual orientations they celebrate if people are truly "born that way").  I don't see how pride could have anything to do with who or what you have sex with.

For example, I have no pride in my nationalities - I had nothing to do with choosing them.  I enjoy the foods and what I know of the customs of both halves of my background, but probably no more than I enjoy the foods of nationalities I have no ties to at all.  I have no pride in any of my parents' accomplishments.  I appreciate that my families migrated to this country and I'm thankful I live here, but simply living here is no reason for pride.  Doing something for the country would be something to take pride in. 

I suppose McThag's post made me think of this.  I suspect the reaction of the people who parade for pride month to my ideas would be to call me a hater.  I don't hate you or your sexuality; I simply don't care about it.  I don't care about anybody's sexuality.  Why should I care?  What consenting adults do in private is so far down on a list of things I care about, it's hard to express.  My current circle of friends are all similar ages to me (I can't think of any younger than about 50) and are all heterosexual married couples.  I don't care about their sexuality either. 

And here's something that might mess with Pride Month paraders: I don't care if you hate me.  You're wasting your life and energy if you do, but if you want to waste your life that's your call.

Friday, June 28, 2019

Everything's Free In The Clown Show

Author Gary Doan at the Libertarian Republic watched the Democratic Clown Posse debates so that you don't have to.  Why?  To keep a running tally of all the things they're promising to give away.
The Democratic primary has become an election for High School President, where everyone is promising vending machines in the cafeteria and larger towels in the locker-rooms. There are so many proposed “free” programs that it may be difficult to keep track without someone compiling them.
And this was just for the first night - Wednesday!  One or more of them promised all of the following as free stuff. 
*Alternate Energy
*Sick Days
*Doubling the EIC
*Family Leave
*Certain Lending
*Foreign Aid
*Mental Health Counseling
*Military Engagements
*Increases To Current Entitlement Programs
*Money For Everyone, Monthly, Just Because [Note: I believe he's referring to Universal Basic Income (UBI) another form of welfare.  SiG]
This reminds me of the time I agreed with Obama.  I'll never forget that day.  It was back in 2009, in an interview with Steve Scully on CSPAN, Scully said, "at what point do we run out of money?" and Obama said, "well, we're out of money now".  It was remarkably honest for any politician.  The exact exchange (for those anal-retentive about misquotes) was:
SCULLY: You know the numbers, $1.7 trillion debt, a national deficit of $11 trillion. At what point do we run out of money?

OBAMA: Well, we are out of money now. We are operating in deep deficits, not caused by any decisions we’ve made on health care so far. This is a consequence of the crisis that we’ve seen and in fact our failure to make some good decisions on health care over the last several decades.
Note that Scully used the wrong words: $1.7 trillion was the annual deficit and $11 trillion the national debt. The situation is far worse now than it was then.  The annual deficit is probably going to be over $1 trillion again, which is better than '09's $1.7T, but the total debt is double what it was back then, $22.4 trillion. (Doubled in just 10 years...)

In a nation with that kind of debt, where does the money come from for all this stuff?  You know it means higher taxes and fees for everything because as RA Heinlein put it, "TANSTAAFL": There Ain't No Such Thing As A Free Lunch, or in this case a free college, free health care, free housing, free Universal Basic Income. Contrary to what the Modern Monetary Theory folks say, we can't just create whatever money we want out of thin air and spend it indefinitely. 

The clown show is just starting.  There are more debates and more pandering to the extreme ends of the socialist spectrum for over another year. 

Pure MMT.  Make up money out of nothing and pay for it.  Which is a good way to end up with money worth less than toilet paper, like Venezuela today.

Thursday, June 27, 2019

Webster Update #2

Most of the shop time in the last couple of weeks was spent on the cylinder. The prints say "12L14 Steel or Cast Iron". I ended up buying 1018 Cold Rolled Steel on my shopping session, so that's what it's made out of.   (Not included in the two weeks was time spent on the side project, drilling out the brass bushing and so on - or other little things going on)

In this photo, you'll note four (#4-40) screws that fasten the frame to the cylinder.  I spent some time trying to figure out how to locate the holes for those screw holes, given the tools I have, and eventually decided to chuck up the cylinder on my Sherline rotary table and drill the four holes as a bolt circle. I did the tapping using my drill press as a vertical guide and then spotted and drilled the other two holes on the drill press.

Overall view with the cylinder and frame resting on the Sherline/A2ZCNC mill.  That large hole on the right is for the spark plug.  The three holes on the side facing the camera, below the centerline of the cylinder, are for the intake and exhaust valves, made as a separate subassembly. 

The cylinder isn't "Done done"; it's about .010" short of the .873 recommended in the drawings. I managed to break my telescopic gauge for measuring the Internal Diameter and am awaiting the replacement. I still have to make the piston and lap that to the match the cylinder.  Both piston and cylinder are intended to end up 0.875", but with them being custom fit to each other rather than interchangeable parts, they could really be any size.  For small, one at a time engines like this, it's pretty common to custom fit the piston to the cylinder.  While a lot of guys make cast iron piston rings in various ways, there are hi temperature polymer rings (Viton is the brand) that work well.  The design doesn't call for any kind of piston rings.

Wednesday, June 26, 2019

A Quiet SpaceX First

Early Tuesday morning was the first night launch of the SpaceX Falcon Heavy.  When we first heard about the launch it was to be Monday night at 11:30 PM EDT, and night launches are always worth watching (when the weather allows).  Sometime around 11:00 or so, they reset the time to later in the launch window, 2:30 AM EDT, so we set an alarm and went to bed.

The mission was complex, with the Falcon Heavy deploying two dozen satellites in a variety of orbits.
Today's launch kicked off a particularly complicated flight, as the satellites onboard needed to be injected into three distinct orbits. All told, the maneuvers required that the rocket's second-stage booster fire four times, with the final deployment scheduled to occur about 3.5 hours after launch. The complicated delivery pattern also dictated the night-launch window, Air Force officials confirmed before the liftoff.
The launch was spectacular, and for the first time, we could watch the return to launch site burns of the two side rockets.  Quite visible in the dark.  The stages returned to SpaceX's twin landing pads on Cape Canaveral, and while trees kept us from seeing the final burns, the sonic booms of the twin boosters going subsonic rattled the house assertively.  A minute or so later, the attempt to recover the core booster on their drone ship OCISLY (Of Course I Still Love You) failed.
The core booster's miss was no big surprise. SpaceX representatives had repeatedly stressed that its touchdown would be the most difficult of the dozens that Falcon 9 and Falcon Heavy first stages have attempted over the past few years, because today's mission required higher-than-normal speeds. Indeed, Of Course I Still Love You was stationed twice as far from shore this morning as it normally is during sea-landing attempts.
About that "twice as far from shore" as normal - the number I've heard somewhere was that it was 775 miles offshore.  This video shows the three booster recoveries.

The new accomplishment in this mission was that SpaceX's unusual way of trying to recover the payload fairings was partially successful.  Their approach is a chase boat with a net on it to catch the falling hardware.  They successfully recovered one of the two halves of the fairing.
The company's net-equipped boat, Ms. Tree (formerly known as Mr. Steven), caught the powerful rocket's falling payload fairing off the Florida coast in the wee hours of yesterday morning (June 25), SpaceX representatives said.

This was a first for the speedy boat, which had come close on multiple occasions but had never managed to seal the deal.

In the net on the left, just below the light, is a light colored chunk with a square edge.  That's the half fairing.  This is an worthwhile thing to do if the company is really trying to scavenge costs out of the process of launching hardware into space.
Payload fairings protect satellites during launch and are jettisoned after rockets reach space. The fairings SpaceX uses for the Heavy and the company's workhorse Falcon 9 rocket, which fall back to Earth in two pieces, cost about $6 million each, company founder and CEO Elon Musk has said.

There's thus ample motivation to recover and reuse this expensive hardware. Indeed, SpaceX equips both fairing halves with parachutes and small steering thrusters, to bring the gear down softly and under control. 
It has been said many times that rocket launching is a tough business.  The safety margins on the hardware are small and the environment is unforgiving.  You have to get used to disappointment.  I'm sure the SpaceX engineers would have rather recovered all three boosters (the two side boosters were used on the Heavy's first mission, so this was their second flight).  I'm sure they would have rather recovered both sides of the fairing.  What the engineers will do is what we always do: study the failures to find what went wrong and what can be done to increase the chance of success next time, without raising prices too much.

Tuesday, June 25, 2019

Solid State Batteries Double Their Energy Density

We learn from Electronic Design magazine this week that a German company called Imec has recently announced they doubled the energy density of their solid state batteries.  Solid state batteries, as the name implies, aren't filled with a liquid (or gel) electrolyte.  They hold the promise of overcoming some of the drawbacks of the very common Lithium Ion batteries.
Solid-state batteries are an emerging option. Believed to be capable of higher energy density (2.5X), faster charging, and more charge/discharge cycles, solid-state batteries are promising candidates for resolving the intrinsic drawbacks of current lithium-ion batteries, such as electrolyte leakage, flammability, and limited energy density.

The major benefits of solid-state battery technology comes from the use of solid electrodes and a solid electrolyte instead of the liquid or polymer electrolytes found in lithium-ion or lithium-polymer batteries.

At the recently concluded European Electric Vehicle Batteries Summit (June 17-19, Berlin) Imec announced a solid-state Li-metal battery cell with an energy density of 400 Wh/liter at a charging speed of 0.5C (two hours), claimed to be a record combination for a solid-state battery. By way of review, charge and discharge rates of a battery are governed by C-rates. The capacity of a battery is commonly rated at 1C, meaning that a fully charged battery rated at 1 Ah should provide 1 A for one hour.
While I appreciate the detail of 400 Watt*Hours/liter, it's not a unit I'm familiar with.  Wikipedia tells me existing Lithium Ion (wet chemistry) batteries have a volumetric energy density in the range of  250 to 620 W·hours/l.  Until now, I've only used numbers for specific energy density in Watt*Hours/kilogram.  They tell me that typical numbers are 100 to 250 W·h/kg, but we've seen numbers of over 400 W*h/kg in these pages.  (note: since it's not likely to be seen as political, this is the sort of fact that Wikipedia can be trusted on)

Imec reports that it continues to follow its roadmap to reach densities over 1000 W*h/l at a charging speed of 2-3C (less than half an hour) by 2024.  1000 W*h/l is quite a bit (61%) better than the numbers Wikipedia offered for current Li-ion batteries.

As I reported back in May of '17,
While battery makers desperately try to figure out how to reach a specific energy of 450 Wh/kg (Watt-hours per kilogram), gasoline already offers 12,000 Wh/kg.

Imec built this solid state battery prototyping lab at the EnergyVille Campus (EnergyVille is a collaboration between the Flemish research partners KU Leuven, VITO, Imec and the University of Hasselt in the field of sustainable energy) and was set up in Genk, Belgium jointly with the University of Hasselt. The pilot line allows manufacturing of small prototype cells of up to 5-Ah capacity.
The facility includes a 300-m2 (3230 ft2) battery-assembly pilot line with a dry room of 100 m2 (1080 ft2) (the manufacture of lithium-ion batteries requires some processing steps to be carried out in a dry room, where the moisture content remains below 100 parts per million; the design and operation of such a dry room adds to the battery’s cost).

Monday, June 24, 2019

About That Entertaining Little Side Project

At the end of the little piece I wrote about making router template bushings for my friend, I said,
Actually, it could be interesting to try to make some of these bushings on my CNC lathe.  I have no brass, but I have aluminum and cold rolled steel in a size that could make some.  Hmmm...
While working on the cylinder for my Webster Engine, I started with a piece of steel (cold rolled steel - CRS) longer than I needed, so that I could be sure that I had plenty to hold in the lathe chuck's jaws.  When I cut off the excess, I noticed that the brass collar for the router bushing almost would screw onto it.  The cutoff steel was small in diameter by just under 1/32", perhaps the depth of the threads (?) but it has been staring at me for days, daring me to try to thread it, saying, "what do you make of me?" and I finally broke down to try. 

The piece of steel I cut off is 1.148" diameter, while the bushing that I measured across the tops of the threads (major diameter) was 1.175, or .027" bigger.  I went back to the CNC threading lathe setup I got working last winter and had a reasonable guess at the thread parameters ready within a few minutes.  Ran the code and no one would be more surprised than I am that the collar threaded on first try.

The collar (brass) works, but the issue is that the tops of the threads don't have the expected, 60 degree, upside down Vee profile they should.  Instead, they're flat topped from not being cut deep enough. I backed off the collar a few turns so you can see it. 

This piece is all the wrong size and shape, it's really just a silly experiment, but it's not like I don't have dozens of little cutoffs like this piece of steel all over the shop.  One with threads is No Big Deal.  But I think if I started out with the real part to get some better dimensions of the threading, I could convince the CNC lathe to turn out a few of these.

Sunday, June 23, 2019

Something Old, Something New

Last Tuesday, I wrote a piece on the destruction of the west focused on the first Third World State, California.

The point of that piece wasn't California per se, it was that the liberal policies embodied there, as perhaps nowhere else, were ending the western way of life with a return to two tiered society common to the middle ages.  A rich class of nobility and a vast underclass of peasants.

Again, this isn't unique to California they're just leading the way into the dystopian future.  Over the years, I've said (and more often hinted) that what I see in the future is not just an economic collapse due to the world's unsustainable debt levels.  I see a real chance for another Dark Ages.  Progressive academicians are pushing Postmodernism which is an assault on the idea of objective reality.  Postmodernists lead us to the modern "my truth" and "your truth"; the idea that there isn't anything other than our perceptions of things.  That works fine for "what's your favorite color?" but is completely wrong for "what's the speed of light?", "will this virus survive in air?" or any interactions with the real world.  No matter how sincerely one believes there's no gravity, simply walking off the top of a building will ensure that they discover their belief is wrong.  There is no "my truth" when it comes to reality.

Postmodernism is the kind of idea that leads people to say, "you have to be a Ph.D. to be that stupid".

Almost two years ago, I wrote a piece on this trend that I still think gets to the heart of it.  I'm going to take advantage of the editor's chair and repost that here with minor edits to shorten it and help readability.

Quote of the Day

From David P. Goldman at PJ Media in his article, "The Triumph of Inequality" (hat tip to Sense of Events):
The great divide is not between black and white, or male and female. We are turning into two races: Eloi who play video games and Morlocks who program them.  ...
If you enlarge the definition of Morlocks from the people who program video games to the people who design the computers those games run on; the hard drives and other components in those computers, and all the other engineers and technicians of all kinds: electrical, mechanical, aerospace, and more, I'm there with him.  I have as much respect for a mechanic who can keep a modern jet engine running optimally as the team who designed it.

Goldman goes on to draw a few contrasts.
Three hundred years ago, pretty much everyone knew how their technology worked. Europe had lived for a millennium on the innovations of the Carolingian Renaissance: the water wheel, the horse collar, and three-field crop rotation. Everyone knew how a water wheel worked. Water pushed the paddles and gears turned the millstones. Not everyone knew how a steam engine worked, but a lot of people did. The same applied to internal combustion engines.

Not only were those technologies easy to understand: They were easy to make. Any competent carpenter could build a water wheel. The Wright brothers built their first airplane in a bicycle shop. Henry Ford made his first internal combustion engine out of spare parts in a backroom at the Edison Illuminating Company of Detroit.

How many people know how a computer works? ... To build a competitive integrated circuit now requires a multi-billion-dollar plant. A numerically minuscule elite invents the technologies we use every day, and a handful of large corporations access the capital required to manufacture them.
He argues that today's technology is too complex.  It's true that as recently as the early 1960s, only a couple of guys were required to design a state of the art radio, (I've met some of them) while today's equivalent radios require a team of hardware and software engineers, with each of those broad categories having several specializations.  It's the rare engineer who can understand all of those domains and design every piece.  To do so is discouraged in the industry for the simple reason that the product gets on the market faster when a team works in parallel than if one guy does everything one subsection at a time.

To dwell on this is to miss the big point: that "numerically minuscule elite" leads all progress in our world and for a nation to have real influence, they need to ruthlessly select for them in a free market of education and ideas.  To deny the opportunity to compete for that education to some portion of its citizens is likely self-defeating, but only the best should advance. Meritocracy, not equality.
Today there are two billion Asians whose parents were immured in utter backwardness who now have a chance at the brass ring. China graduates four times as many STEM bachelors as the United States and twice as many PhDs; a generation ago the Chinese university system had just begun to pick itself up out of the ruins of the Cultural Revolution
Part of the glue that held the Chinese imperial system together these past three thousand years is the chance that every Chinese has to get rich by passing what used to be the Mandarin examination.
The byword in American education is "No child left behind." In Singapore, it's "You must be exceptional to survive."
America is at a distinct disadvantage to Asia.  We are numerically quite a bit smaller than China or India.  That means fewer to choose from to find that minuscule fraction.  

While the idiots on the left are consumed with equality of outcomes for everyone, rather than the equality of opportunities, Goldman gives the simple, inescapably true message that we should ruthlessly search for excellence instead. 
If we focus on equality rather than excellence, we will be overwhelmed by the rest of the world.  A generation from now there will be a word for an American who works for an Asian: "Employed." Our future lies in the talented few, not the mediocre masses -- and if we repudiate them, the future will repudiate us.
Are we headed for another dark ages?  Cloistered in the future equivalents of monasteries may be the people who know how to do things: the Morlocks.

A commenter there retold a story that I know I've seen before, and I'll bet most of you have, too.
I remember a story about how some archeologists excavated a Roman villa in East Anglia and found that while it was occupied by Romans soon after the conquest of Brittania it had all the comforts of civilization including central heating. As they continued to excavate they found strange burn marks in what was the great room which were accurately dated to a time three or four generations after the Romans left. Why the burn marks? Campfires. Within 100 years the people living there had forgotten how to make central heating work. They had probably forgotten that it existed at all.

Similarly, records kept by the Romans showed agricultural productivity for the same area three times what it would be when the Domesday Book started keeping records again. The farmers after the fall of Rome not only COULDN'T achieve that productivity, they didn't know it existed in the first place.

A modern generation Digital Signal Processor chip.  It takes the industrial might of billion dollar companies along with teams of engineers to design and make these.  If society collapses, I can easily see us losing the knowledge of how to make these.  I can see after a generation without them, people not being able to imagine they existed at all.

An aspect I didn't specifically mention in there might be apparent if you think about it.  There's a handful of companies that make these DSP chips.  An even smaller handful make high performance analog electronics.  The number of people who design these parts is shockingly small.  How many?  I honestly don't know, but I wouldn't be surprised if the all the principal engineers who run the teams of lower level engineers that turn their conceptual designs into silicon could fit into a good-sized convention center.   

Saturday, June 22, 2019

Open Source Drone Hardware Software Competition

Semiconductor manufacturer NXP has announced a set of open competitions among drone developers called the HoverGames.  The first is to develop software to allow drones to help fire fighters and is going on right now. 

Join the first HoverGames Challenge: Fight Fire with Flyers

Fires cause billions in damage, destroy entire towns and forests and put countless lives in danger, including first responders at the front line.

Join the first HoverGames Challenge and build a robotic drone system to help firefighters in their mission of saving and protecting lives. The NXP HoverGames drone development kit includes everything you need to get started on your flying robot. The Fight Fire challenge ends Oct. 31. See official rules for details.
NXP's practical interest here is to highlight their flight management unit (FMU), based on their Kinetis K66 Arm Cortex-M4 microcontroller.  Secondarily, they might get some open source software to use out of the contests.  They offer kits but use of their kits isn't mandatory.
The NXP Flight Management Unit.

The FMU is based on PX4 open-source software. PX4 grew out of the Linux community. 
PX4 is an open source flight control software for drones and other unmanned vehicles. The project provides a flexible set of tools for drone developers to share technologies to create tailored solutions for drone applications. PX4 provides a standard to deliver drone hardware support and software stack, allowing an ecosystem to build and maintain hardware and software in a scalable way.

Historically, PX4 grew from the PIXHAWK project at ETH Zurich, which the PIXHAWK MAV was specifically designed to be a research platform for computer vision based flight control. The project now counts more than 300 global contributors and is used by some of the world’s most-innovative companies, across a wide range of drone industry applications. The open source community around the Pixhawk open autopilot hardware and the PX4 flight stack is the largest industry-backed development community in the drone space today.

Even with the PX4 open source software, anyone who has spent time integrating hardware and software will tell you that your troubles are just starting.  That's where the kits come in: one of the most painful aspects of developing the hardware/software combination, getting them to talk to each other, has been done and the drone is close to being flyable as received.   (It might be flyable - I don't think the website was very clear on that).
In particular, all of the kit’s parts have been integrated, which is a big task. Developers could spend months just getting hardware and software to the point where a drone is flying. This includes the use of the PX4 autopilot software that’s managed by, which is also part of the Linux Foundation. In addition, hosts projects like MAVLink, a communication protocol used by PX4, and a ground-station control system.

A host like an i.MX 8 or NVIDIA Jetson TX2 running the Robot Operating System (ROS) can control the PX4 system via MAVLink using MAVROS. The FMU has headroom for applications, but it lacks the horsepower to analyze video streams that one of these other hosts can easily handle.
The assembled HoverGames carbon-fiber platform can build on PX4 software, enabling developers to concentrate on the problem instead of worrying about integration. The NXP web site lists the almost ready to fly kit at $460.

A sample of some drones already flying the PX4 software.  

The open source aspects of the HoverGames aren't even slightly surprising. I'm also willing to bet there's some really good software out there that's being kept proprietary for the company that wants to sell or lease it; these companies won't be involved in the HoverGames.  Still worth keeping an eye on. 

Friday, June 21, 2019

With Apologies

Offered with deepest apologies to the late, great, Glenn Frey and (of course) Jackson Browne.   And Brigid

Any image that combines bad jokes, Star Trek and Eagles references has to be posted here. 

Thursday, June 20, 2019

Men In Black - International

22 years ago, the Men in Black comic books came to the big screen, led by Will Smith and Tommy Lee Jones.  As always, with a successful first film, a sequel came with MIB II in '02 and MIB 3 came 10 years later in '12.  Although neither one of us ever read the comics, goofy sci fi is right up our alley and we saw them all. 

I started hearing about an extension of the franchise several months ago, and more details since then.  Men in Black: International opened last weekend to a worldwide gross of $104 Million versus an estimated production cost of $110 M.  I think it's safe to think there will probably be another sequel. 

From the view of the cast, this is virtually a complete reboot.  Only Emma Thompson, who headed the New York office as Agent O in MIB 3, comes from the previous movies.  The new agents are straight outta the Marvel Universe, Chris Hemsworth (Thor) as Agent H and one of the fan favorites from Thor Ragnarok, Tessa Thompson (Valkyrie) as Agent M.  As I've mentioned many times, I thought Thor Ragnarok was the peak of the Marvel movies.

MIB: International comes close.  First off, I've become a fan of Chris Hemsworth.  For a guy who could easily play the "too good looking to be true" action hero, he has a self-deprecating quality that comes across well on screen.  (It's rumored the "beer belly Thor" from Endgame was his idea - and that idea really struck me funny).  To be honest, I didn't think much of Tessa Thompson in Ragnarok.  She was important to the plot, but I just didn't notice her much.  In this movie, I thought she had a good on-screen personality and brought the character to life.  In the IMDB universe, they talk about pairing the two of them for their "on-screen chemistry" in Ragnarok and moving that to the MIB universe.  Ms. Thompson brings up the point that all of the other MIB movies are "buddy films" that are all about the relationship between the two main characters, agents J and K and this one becomes a buddy film, as well.

The movie opens with Agent M (Molly) as a young girl.  Her family has an encounter with some aliens and are visited by the MiB.  A mainstay of the movie franchise is the agents flash a "Neuralyzer" in the eyes of witnesses, which wipes the memories of what they've just seen so that the general public doesn't get terrified that aliens live among us all the time.  When the agents Neuralyze her parents, Molly is hiding behind curtains talking to the furry little alien in her room.  She grows up constantly searching for everything she can learn about the mysterious MiB, eventually tracking them down and walking into MiB headquarters to try and join.

The plot of the movie concerns a problem in the organization.  There's a leak from MiB in London where they send Probationary Agent M on assignment.  As always, the fate of the world is at stake as different alien races bring their hostilities to Earth.  As always, tons of sight gags, many different alien costumes, alien weapons, amazing MiB technology, and lots of witty one-liners.  

Definitely worth the time to go see.  Left me wishing there was a bit more movie; at 114 minutes, not quite two hours duration, it's much shorter than Avengers Endgame.

Chris Hemsworth and Tessa Thompson riding a rocket-powered, levitating "motorcycle" through the streets of Marrakesh.

Wednesday, June 19, 2019

Reparations and the Gun Control Fight?

As you've undoubtedly heard, the House Democrats today held hearings to great fanfare to discuss creating a committee to study reparations for slavery.  It is safe to say that while some may claim being descendants of slaves, nobody today has been directly injured or damaged by slavery in the US.  It's equally safe to say that nobody alive today owned any slaves in the US. 

Considering that the population of the country is ten times larger than it was when slavery was legal, it's also safe to say that most of the people in the country weren't remotely involved in slavery in the US- they came to the country after the end of slavery.  That's the case with my family.  Neither side of my family came into the US until the 19-teens.  Is it somehow "fair" to demand payment from someone who wasn't involved in the situation - to give to someone wasn't involved in the situation?  One can imagine a person who had been a slave in another country but somehow made it to the US and now will be taxed to pay reparations to someone who wasn't in this country, either, but belongs to the "affronted class".  

How far back do we go?  Only since 1776?  Slavery wasn't a US institution; it has existed for all of recorded history.  The US and Europe in the last 150 years are the first societies to get rid of slavery.  I've heard that in the entire 350 years of the African slave trade, 12 Million slaves were sold out of Africa.  Of those, about 350,000 ended up in the US (most ended up in Brazil).  Today, there are more than 20 million slaves, largely in Islamic countries.  That's right - more slaves in captivity today than in the entire years of the African slave trade.   

I'm afraid from what I heard that the congress critters hearing the testimonies have mental images of the historical story that are bad caricatures of the reality.

So what does that have to do with the gun control fight?

Very simple.  Nobody likes being punished for things they didn't do.  One of the most common quips when the anti-2A forces start talking about new controls is, "my guns and I didn't do anything - why are you punishing me?"  Sorry to hear about your bad day in wherever, but my guns are in my safe and we're all hundreds of miles from the shooting.  Why do you think you get to regulate me?  

One of the moments most dripping with irony in the last 16 months was last April when Marjory Stoneman Douglas High School in Parkland demanded students carry clear backpacks, and the students bitterly complained about being deprived of privacy.  The same students who were blaming the millions of American gun owners and the NRA, all of whom had absolutely nothing to do with the February shooting, started complaining they were being punished for the actions of others.  And yet they seemingly didn't realize that was exactly what they themselves had been doing. 

They didn't like it.  Nobody likes getting punished for things they didn't do.

It seems to me that if we could invoke that imagery and create that feeling in the "man on the street", the voters that politicians are rallying to support their gun controls might lose the support.  It's a place where internet memes and guerilla marketing could make a difference. 

(1860 Census - the population today is a bit over 10x that.  Source)

Tuesday, June 18, 2019

The Destruction of the West - California in the Lead

Thanks to lead-in from 90 Mile From Tyranny, we find an epic piece written by Victor Davis Hanson in National Review, "California: America's First Third World State".

California, as the biggest liberal enclave in the US, stands out from the rest of the states in the way that it seems to strive to attain the ideal social structure that so-called progressives long for:  a medieval society of royalty and peasants (as long as they're the ones on top).  In modern terms that means no middle class, just a wealthy, nobility class and a much larger lower (or under) class of indentured servants who keep them in power.

VDH opens with this trenchant observation:
Third World symptomologies are predictably corrupt government, unequal or nonexistent applicability of the law, two rather than three classes, and the return of medieval diseases. Third World nations suffer from high taxes and poor social services, premodern infrastructure and utilities, poor transportation, tribalism, gangs, and lack of security.

Another chief characteristic of a Third World society is the official denial of all of the above, and a vindictive, almost hysterical state response to anyone who points out those obvious tragedies. Another is massive out-migration. Residents prefer almost any country other than their own. Think Somalia, Venezuela, Cuba, Libya, or Guatemala.
It's really worth reading the whole thing, but VDH puts together a strong case to back his points.  I'll excerpt a few here.
By many criteria, 21st-century California is both the poorest and the richest state in the union. Almost a quarter of the population lives below the poverty line. Another fifth is categorized as near the poverty level — facts not true during the latter 20th century. A third of the nation’s welfare recipients now live in California. The state has the highest homeless population in the nation (135,000). About 22 percent of the nation’s total homeless population reside in the state — whose economy is the largest in the U.S., fueling the greatest numbers of American billionaires and high-income zip codes.

But by some indicators, the California middle class is shrinking — because of massive regulation, high taxation, green zoning, and accompanying high housing prices. Out-migration from the state remains largely a phenomenon of the middle and upper-middle classes. Millions have left California in the past 30 years, replaced by indigent and often illegal immigrants, often along with the young, affluent, and single.
California’s transportation system, to be honest, remains in near ruins. Despite the highest gas taxes in the nation, none of its major trans-state freeways — not the 99, not I-5, not the 101 — after 70 years off use, are yet completed with six lanes, resulting in dangerous bottlenecks and wrecks. Driving the 99 south of Visalia, or the 101 near Paso Robles, or the 5 north of Coalinga is right out of Road Warrior — but not as dangerous as the fossilized two-line feeder lines such as 152 into Gilroy, or the 41 west of Kettleman City. The unspoken transportation credo of Jerry Brown’s aggregate 16 years as governor apparently was “If you don’t build it, maybe they won’t need it.”
In 1973, when I first visited and lived in Greece, the roads were medieval. The old Hellinikon Airport was dysfunctional, if not creepy. Highway rest stops were filthy. I have lived in or visited Greece in the ensuing 45 years since, including occasionally after the 2008 meltdown and European Union standoff. And yet today, the freeways, chief airport, and rest stops of relatively poor Greece are in far better shape than are California’s. LAX’s poor road access, traffic, uncleanness, crowds, and chaos seem premodern compared with the current Athenian airport.
Power outrages are characteristic of Third World countries. Here in California we are advised to brace for lots of them, given that our antiquated grid apparently contributes to brush fires on hot days. As a native, I do not remember a single instance of our 20th-century state utilities shutting down service in the manner that they now routinely promise.
California’s cycles of wet boom years and dry bust years continue because the state refuses to build three or four additional large reservoirs that have been planned for more than a half-century, and that would store enough water to keep California functional through even the worst drought. The rationale is either that it is more sophisticated to allow millions of acre-feet of melted snow to run into the sea, or it is better to have a high-speed-rail line from Merced to Bakersfield than an additional 10 million acre-feet of water storage, or droughts ensure more state control through rationing and green social-policy remedies.
California schools are usually in the bottom decile of national rankings. No one in polite conversation asks why that is so, given that the state’s K–12 schools used to be among the most competitive in the United States.

Yet, again in medieval fashion, the professional schools and science and technology departments of California’s premier research universities — Cal Tech, Stanford, UC Berkeley, UCLA, USC — are among the highest-rated in the world. Imagine something like the scribal oases of Padua, Oxford, or Paris in an otherwise frightening 13th century. If one wishes to be schooled as an electrical engineer or cancer researcher, California is an attractive place; if one wishes to be a knowledgeable graduate of a public elementary and high school, it most certainly is not.
California now has the nation’s highest basket of sales, gas, and income taxes. With a state surplus, and a slowing economy, one would think that the legislature and governor would pause before even considering raising more taxes. After all, new federal tax law limits write-offs of state and local taxes to $10,000 — radically spiking upper-bracket Californians’ federal tax liabilities.

Yet the rule in California is to punish the upper middle class while pandering to the rich and romanticizing the poor. Thus, the legislature is now considering a punitive new inheritance tax, and it just imposed an Internet sales tax.
What caused this lunacy?

A polarity of importing massive poverty from south of the border while pandering to those who control unprecedented wealth in Silicon Valley, Hollywood, the tourism industry, and the marquee universities. Massive green regulations and boutique zoning, soaring taxes, increasing crime, identity politics and tribalism, and radical one-party progressive government were force multipliers. It is common to blame California Republicans for their own demise. They have much to account for, but in some sense, the state simply deported conservative voters and imported their left-wing replacements.
Go read the rest.  Yes, I left some. 

In many issues and at many times, California has started changes that filtered into the rest of the country.  Many of the movements that are pushing California into third world status are elsewhere in the country.  Seattle.  Chicago.  Portland.  New York City.  Jersey City.  New Orleans.  And others.  These things VDH describes should be flashing warning signs, saying "don't do what they did", yet too many seem to want to go down the path into the third world. 

Monday, June 17, 2019

Confidential to New York Democrats - The Vietnamese Communists Saw Rent Control was Stupid

According to the Marginal Revolution, rent controls are returning to New York (hat tip to FEE)
The bills announced on Tuesday night by the Democratic leaders of the State Senate and the Assembly would abolish rules that let building owners deregulate apartments and close loopholes that permit them to raise rents.

The legislation would directly impact almost one million rent-regulated apartments in New York City, which account for more than 40 percent of the city’s rental stock, and allow other municipalities statewide beyond New York City and its suburbs to adopt their own regulations…

The rent regulation package, which is expected to be approved before the end of the week, is perhaps the most resonant symbol of the change in power in Albany since Democrats took complete control in November.
It turns out that actual communists are smarter about their failures than the American "wannabe communists".  In the 20 years after the Vietnam war, the communist leadership realized that rent controls destroyed Hanoi more effectively than US bombs ever could. 
NEW DELHI—A “romantic conception of socialism” … destroyed Vietnam’s economy in the years after the Vietnam war, Foreign Minister Nguyen Co Thach said Friday.

Addressing a crowded news conference in the Indian capital, Mr. Thach admitted that controls … had artificially encouraged demand and discouraged supply…. House rents had … been kept low … so all the houses in Hanoi had fallen into disrepair, said Mr. Thach.

“The Americans couldn’t destroy Hanoi, but we have destroyed our city by very low rents. We realized it was stupid and that we must change policy,” he said.

—From a news report in Journal of Commerce, quoted in Dan Seligman, “Keeping Up,” Fortune, February 27, 1989.
Fee does a little Economics 101 on the subject that might help your denser friends who want rent controls.

I'm sure the socialists will say it's the nasty, greedy landlords, or the Big Renters manipulating the city that force this, not the invisible hand of the free market.  I was saying elsewhere today that you never hear the Democratic Socialists say that if someone is manipulating the cities that government is at fault, too.  It's stupid to only blame someone paying a kickback (also known as a bribe) when taking the bribe is a crime just like paying one.  Corruption is a crime for both parties.  Monopolistic practices are a crime for both the company and the government regulators.

Everybody has been in the situation where the rent was higher than they'd like.  I've got that tee-shirt, too.  The free market is always better at fixing things like the supply of rental units than government committees will be.  Yes, it's an axiom. 


Sunday, June 16, 2019

Entertaining Little Side Project

Although my main project in the shop is the Webster engine, I still can and do use the shop for other little things.  I had one of those this week. 

Last year I mentioned a friend I have who makes wooden signs for entertainment and a little supplemental income.  He had brought me an idea for an improvement to his setups, making a version of his plastic templates out of aluminum that can be dropped onto a wood blank and help him fixture it much faster.  A few weeks ago, he came to me with another idea.  It concerns the metal bushings that sign routing kits use (example product and photo).

It's important to point out that this view of the bushing is upside down.  That circular, brass disk with a protruding collar is down in contact with the template while he's cutting.  That disk is also in plane with the base of the router so that it slides smoothly, without tipping catching, or getting stuck on an edge.  

He had noticed that sometimes it seemed the raised collar (which is sized to be just a few thousandths larger than the outside diameter of the router's cutter) wasn't allowing him to move the router properly because wood chips would get stuck between the bushing and the template.  He reasoned that even though he had a vacuum attached to the router, the brass covered the chips and there was no way for the vacuum to get at them. 

So he asked me if it would be possible to perhaps mill out sectors of the bushing leaving enough metal so that it was still a working bushing.  I thought about this for a while and said I could do a few different diameters but not everything he had - the end mills to cut out a partial groove might not be available in every size that we'd need.  I countered that there'd almost certainly be any size drill bit one would ever need and that I could drill an array of holes - kind of like the lug nut holes in a tire rim. 

We pondered and I went home with a damaged sample to draw it up in CAD and play with clearances for given drill bit sizes. 

This week, I drilled the holes in the sample piece and then brought it back over for him to try.  This was designed by determining the radius of the circle of holes (in CAD), chucking the bushing in the rotary table, and drilling a hole every 45 degrees at that radius.  The bushing surface is now mostly open space. 

Playing in CAD told me that for this size bushing, for 1/4" diameter router bit, the largest drill bit I'd feel comfortable using was 7/32" - 0.219".  I haven't tried to see how much room there is for other sizes, and it might be that three arcs cut out with an end mill while spinning the rotary table.  If I had another of these, I might try to do that with a 3/16" (0.188") end mill (I think I have one...) cutting three arcs. 

Actually, it could be interesting to try to make some of these bushings on my CNC lathe.  I have no brass, but I have aluminum and cold rolled steel in a size that could make some.  Hmmm... 

Saturday, June 15, 2019

Congrats to Canadian Space Agency and SpaceX

I noticed this story on the ARS Technica Rocket Report last week and waited for this week to see if the scheduled launch took place.  With a diversion to the Tesla and SpaceX fan website, Teslarati
As early as June 12, SpaceX will attempt to launch a trio of Canadian satellites worth $1 billion from Vandenberg Air Force Base. Built by Maxar for the Canadian Space Agency, the Radarsat Constellation Mission comprises three remote-sensing spacecraft designed with large surface-scanning radars as their primary payload
The launch took place on the 12th, with a beautiful remote view of the rocket breaking through the morning fog (video here).

The video is over an hour long, but if you watch until the booster lands back on Vandenberg AFB, that's near the 20:30 minute mark, with liftoff at almost 12:38.

The launch and booster recovery are not the reason for this post.  The $1 Billion dollar mission is from an agency that has an annual budget of about $250 Million.  That's right, four years worth of the agency's entire budget for this mission, which boggles my mind.  It's not surprising that they spent a bit of time haggling with SpaceX to find a "lightly used" booster and get the lowest price they could with what they thought to be their highest chances of success.  This is the part Teslarati adds:
From an external perspective, forgoing a twice or thrice-flown Falcon 9 Block 5 booster after nearly a dozen successful demonstrations does not exactly appear to be a rational decision. However, whether it was motivated by conservatism, risk-aversion, or something else, Maxar and CSA likely have every contractual right to demand certain conditions, as long as they accept the consequences of those requirements. In the case of RCM, the customers accepted what they likely knew would be months of guaranteed delays to minimize something they perceived as a risk.

To some extent, it’s hard to blame them. After going more than $400M over budget, the Maxar-built trio of upgraded Radarsat satellites are expected to end up costing more than $1 billion. CSA’s annual budget typically stands around $250M, meaning that this single launch is equivalent to four years of space agency’s entire budget. A failed launch would be a huge setback. Additionally, RCM will likely become the most valuable payload ever launched by SpaceX, beating out the Air Force’s ~$600M GPS III SV01 spacecraft by a huge margin. For RCM, mission assurance is definitively second to none. 
A few hours after the launch, prime contractor Maxar said the satellites were "performing according to plan.", so it sounds like the mission is a success. 

Again, congrats to the Canadian Space Agency, Maxar and SpaceX. 

Friday, June 14, 2019

The Days of Trillion Dollar Deficits Are Returning

During the Obama years, deficits of a trillion dollars were not uncommon (example).  You may think that the economy is fundamentally different today, and that annual deficits are shrinking.  Despite that fact that Trump's tax cuts led to record tax revenues, it looks like we'll be close to a $1Trillion deficit for this fiscal year.  Maybe over that.  We'll hit the trillion dollar limit if the next four months of 2019 transpire along the same average spending per month as the first eight months did.
The gap between the amount the government takes in and spends came in at $207.8 billion last month, the Treasury Department said (pdf) Wednesday, nearly 42% higher than a year earlier. The increase happened in part because of June 1 falling on a Saturday, a non-business day, meaning some benefit payments were made earlier than usual.

Lawmakers typically try to reduce the deficit when the economy is strong, but recent legislation has taken it in the opposite direction. In the first eight months of the fiscal year, the deficit increased about 39% from a year earlier to $738.6 billion.
Let me show my work.   Eight months is 8/12 or 2/3 of the year.  Multiply the deficit through eight months by the reciprocal of 2/3 (3/2) to extrapolate the same spending rate to the year and your calculator tells you $1.1 Trillion deficit this year.  It's not a great way to determine the deficit for the year because each month doesn't necessarily have the same spending as every other month - but it gets you "close enough".

As a matter of interest, while looking for some background information on this topic, I ran into a piece I posted in February of '18, "Ron Paul Was Right" that offered a prediction for this year's deficit that's remarkably close to what I just derived.  The article started with a quote from Senator Paul saying that the government spends closer to $2 Million/minute.
The Committee for a Responsible Federal Budget (CRFB), an independent think tank, projects that the deficit for FY '19 will balloon to $1.2 trillion in FY 2019, or $2.3 million per minute.
I don't know exactly whom to pin this deficit spending on.  The House starts spending, and they're all Nancy's little babbling numb nuts.  The Senate is in Stupid Party control, where spending bills can be modified, and President Tariff keeps talking about adding a trillion dollars of spending on infrastructure - although there are no real details to relay to you

In the end, it probably doesn't matter who did it because the pattern over the years is that the party out of power complains about deficits and spending until they get power, and then the roles switch.  Now the party out of power has economists telling them it doesn't matter and they can spend whatever they want.  They can't run out of dollars like the football stadium can't run out of points.  When they eventually get power back, it's going to be a fun experiment to watch.  From another planet. 

I tend to believe that things that can't go on forever won't go on forever and that all bubbles pop.  Eventually "political reality" collides with real reality.  There is a real world, with real consequences.  It's not all in our minds.  Economic collapses happen around the world all the time.  I've been predicting one for nine years, now.  So don't look at me. 

One thing is certain.  With record tax revenues, that's a vivid demonstration that it's not that we don't tax enough -- "It's the spending, stupid!!"

(I have to admit the way I report on economics isn't as ... interesting to read as John Wilder, who puts his economic plots on pictures of girls in bikinis)

Wednesday, June 12, 2019

Because I Like the Name

It's natural that the news in the tech world tends to focus on the glamorous aspects: self driving cars, 5G wireless networks, autonomous AI, sexbots and so on.  In reality, a lot of applications are pretty mundane.  Autonomous monitors that could survey a section of forest or some amount of land and work on its own for days or weeks at a time would solve a few problems.

With that in mind, let's introduce SlothBot - an autonomous robot under development at Georgia Tech and inspired by a sloth:

“In robotics, it seems we are always pushing for faster, more agile and more extreme robots,” said Magnus Egerstedt, the Steve W. Chaddick School Chair of the School of Electrical and Computer Engineering at the Georgia Institute of Technology and principal investigator for Slothbot. “But there are many applications where there is no need to be fast. You just have to be out there persistently over long periods of time, observing what’s going on.”

Based on what Egerstedt called the “theory of slowness,” Graduate Research Assistant Gennaro Notomista designed SlothBot together with his colleague, Yousef Emam, using 3D-printed parts for the gearing and wire-switching mechanisms needed to crawl through a network of wires in the trees. The greatest challenge for a wire-crawling robot is switching from one cable to another without falling, Notomista said.
SlothBot consists of two plastic bodies connected by an actuated hinge with one body holding a couple of small solar panels.  SlothBot doesn't swing between branches like its namesake; instead, wires or ropes are pre-strung in areas the robots will operate.  Each body houses a driving motor connected to a rim on which a tire is mounted. The use of wheels for locomotion is simple, energy efficient and safer than other types of wire-based locomotion, the researchers say.

So far, SlothBot has operated in a network of cables on the Georgia Tech campus. Next, a new 3D-printed shell – that makes the robot look more like a sloth – will protect the motors, gears, actuators, cameras, computer and other components from the rain and wind. That will set the stage for longer-term studies in the tree canopy at the Atlanta Botanical Garden, where Egerstedt hopes visitors will see a SlothBot monitoring conditions as early as this fall.
Real-life sloths are small mammals that live in jungle canopies of South and Central America. Making their living by eating tree leaves, the animals can survive on the daily caloric equivalent of a small potato. With their slow metabolism, sloths rest as much 22 hours a day and seldom descend from the trees where they can spend their entire lives.

“The life of a sloth is pretty slow-moving and there’s not a lot of excitement on a day-to-day level,” said Jonathan Pauli, an associate professor in the Department of Forest & Wildlife Ecology at the University of Wisconsin-Madison, who has consulted with the Georgia Tech team on the project. “The nice thing about a very slow life history is that you don’t really need a lot of energy input. You can have a long duration and persistence in a limited area with very little energy inputs over a long period of time.”

(Two-toed sloth using cables on Georgia Tech campus as a Sloth Monorail)

The operational plan for the SlothBot is exactly that last sentence: hang around for a long time in a small area, observe and record, then move to an area of bright sun to recharge.
The researchers also hope to test SlothBot in a cacao plantation in Costa Rica that is already home to real sloths. “The cables used to move cacao have become a sloth superhighway because the animals find them useful to move around,” Egerstedt said. “If all goes well, we will deploy SlothBots along the cables to monitor the sloths.”
About 12 years ago, I consulted to local school on the radio system for a monitor like this that would be left in the field and then report back from time to time.  Energy usage becomes a major concern - budgeting how big the battery is, how much power individual systems are allowed and a lot of tough, systems engineering questions.  Egerstedt is no stranger to these decisions.
Egerstedt is known for algorithms that drive swarms of small wheeled or flying robots. But during a visit to Costa Rica, he became interested in sloths and began developing what he calls “a theory of slowness” together with Professor Ron Arkin in Georgia Tech’s School of Interactive Computing. The theory leverages the benefits of energy efficiency.

“If you are doing things like environmental monitoring, you want to be out in the forest for months,” Egerstedt said. “That changes the way you think about control systems at a high level.”

Flying robots are already used for environmental monitoring, but their high energy needs mean they cannot linger for long. Wheeled robots can get by with less energy, but they can get stuck in mud or be hampered by tree roots, and cannot get a big picture view from the ground.

“The thing that costs energy more than anything else is movement,” Egerstedt said. “Moving is much more expensive than sensing or thinking. For environmental robots, you should only move when you absolutely have to. We had to think about what that would be like.”

Closeup of SlothBot showing the 3D printed gears. 

There's a video of SlothBot in motion

Tuesday, June 11, 2019

A Webster Update

I've completed the next part on the Webster engine I've started building.  The first part was almost two weeks ago, May 30.  That's a long time to make a plate with seven holes in it, but there have been some extenuating circumstances.  The Game of the Other Thrones kept me out of the shop a couple of days itself.  

Top side: 

The part fought me in some ways, too.  There's an obvious rectangle of four holes on the left, with a pair of smaller holes mixed in with them.  The smaller ones get tapped 6-32 and one of them fought me bitterly.  It's a long story centered on breaking the tap.  The Click Of Doom happened when I started to back the tap out, which I guess means the chip had clogged the tap.  I was tapping on the mill's table, where the holes were drilled, and had a 1/8 dowel pin in the drill chuck on the mill which went into the gap on the top of the wrench holding the tap.  I'd advance the tap 1/2 turn then lower the pin to keep the tap very close to perfectly vertical, and I must have not backed the tap out often enough.  I'm fairly sure I had not backed it completely out yet and this was going to be the first.

Well, that's probably TMI, but I need to tap a lot of 6-32 blind holes in this thing and I'm pretty sure the only taps I've ever broken were 6-32.   I've also read it's the hardest common thread for tapping; something about the ratio of the depth of the thread to root diameter.  I need to buy some more 6-32 taps - I only have one left.  Maybe a gross will get me through.

Bottom side:

The rectangular pattern holes and the big one in the upper left in this view get a countersink that required I buy a new set of 82 degree countersinks; everything I own is 90 degree.  It's not an optical delusion that the bottom looks like a better finish.  I should have noticed that and machined it with that side up.  I'll see if some finish work can pretty it up. 

The next parts are modeled and ready to machine.  These are two side plates made from 5/16" thick aluminum. 

The faint green outline represents the sheet they'll be cut from, the two parts are in blue and the red lines are the tool paths for cutting out the two parts from one small plate. 

I have another piece of metal ready to work on, the cylinder, which is cold rolled steel.  I've done a little work on that, but barely scratched the surface (if you'll pardon the pun).  Not quite sure which part gets the attention to get completed first.  There are arguments in favor of both. 

Monday, June 10, 2019

A Rather Unusual Saturday

We did a first for us and went to a weekend concert in the biggest auditorium in the area, the King Center for Performing Arts

But you don't care about where we went; you want to know whom we went to see, right?  The "first for us" is we went to see Weird Al Yankovic on his Strings Attached Tour that started a few days ago.  Al was in town a few years ago and we didn't go; ever since then Mrs. Graybeard has talked about not missing him if he comes back.  Last January when she saw he was coming it was a natural to grab tickets before they sold out.  And it was sold out.
I feel a disturbance in the force... as if hundreds of people are closing their browser tabs.
The reason for the name is that the concerts use (what they called) a 39 piece symphony orchestra.  Rather than bring a symphony on the road with them - with all the complications that entails for travel, accommodations and so on - they use a local orchestra.  I assume the musicians get the music and program they'll be playing long in advance. 

Confessing that I would actually pay money to see Weird Al probably lowers some of your opinions of me (and for many, nothing could make your opinions of me lower), but I've had a soft spot for music parodies since Alan Sherman in 1963.  I appreciate clever language, puns and lyrics that lead to vivid visualizations, but it simply has to fit the meter of the song! 

The reason for the tour is a new album so the tour itself is a bunch of old favorites and new music (Mental Floss says this is Al's biggest selling record ever).  They didn't play all my favorites - Al has been doing this for over 30 years, there isn't enough time to play everything - but they played a lot of good stuff and it was a very enjoyable show.  It's entertainment, after all, and Al tries to be entertaining.  In addition to the symphony, there's just an eight person act band, one guitar, one bass, one keyboardist a drummer and three women doing backup singing.  They mix in a bit of multimedia by way of a large slide show or video in the background.

The show starts with the symphony playing favorite songs, like the themes from various movies (Indiana Jones, Superman, and a few more) - then everyone took off for 20 minutes.  The orchestra plays backup throughout the evening.  Al uses a lot of energy in the show, and is performing for about 90 minutes including an encore of one of his big songs, The Saga Begins.  He does several costume changes, and there are moments where Al basically goes into the first few rows and plays with the audience.  This is "optional at extra cost" - the VIP package that includes meeting Al and the band after the show, pictures, and a few mementos.   

The craptastic iPhone picture of Al during The Saga Begins is a reminder of the only thing about the evening that really torqued me off.  On the King Center's web page, they say that interchangeable lens cameras aren't allowed, or a camera with a lens bigger than 6", so I brought my point and shoot camera, which isn't going to challenge the image quality of a long lens on a good camera, but is going to be sharper than the cellphone.  The event security guys wouldn't let me in with it.  I quoted chapter and verse of that page, and took it up the chain of command as far as I could, but (of course) they were not going to allow me to challenge their authoritah.