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Posted by Jack Crossfire | Jul 11, 2017 @ 12:20 AM | 14,902 Views
The Shot Well was interviewed on the space show here http://www.thespaceshow.com/show/22-...wynne-shotwell . Here, she revealed they're renaming the ITS back to the BFR, big f*cking rocket. There was 1 of the few references to her husband, so the internet needs to stop writing Ms. They've fired the scaled raptor engine over 25 times, but have not even decided what its full size should be. The full size is determined by the knee in cost/performance & is converging on 2.5x the scaled size of 200,000lbf. They're now considering another Falcon 9 revision with raptors. Still impressive that the scaled raptor is as powerful as the final merlin. They could just swap in the scaled ones.


Their mane focus is the falcon heavy demo flight, dragon 2, & falcon 9 block 5. Then there's faring recovery, stage 2 recovery. There's no material investment on the BFR, the lunar flight, or any of the other stuff on Musk's twitter feed. There wasn't anything on what happened to the carbon fiber tank besides they're still trying. The Falcon 9 block 5 has valves rated for many cycles & tanks rated for many more pressure cycles. They're doing "some work" on the octaweb. Blocks below 5 can only fly 3 times.


It seems if Musk put just the effort on boring & hyperloop on the BFR, it would be a headline maker, but Tesla still isn't making money & there aren't enough roads to drive the number of cars he needs to sell. People are going to put a lot more...Continue Reading
Posted by Jack Crossfire | Jul 09, 2017 @ 06:15 PM | 3,771 Views
After much studying, the decision was made to restart the party with a $300 gopro hero 4 black. There are an awful a lot of action cams & ambiguous chicken scratch to digest, but here are the facts a lion can discern:

All the sub $100 action cams by noname Chinese brands have truly awful, hazy, blurry picture quality. The pros are still far beyond in picture quality. Extracting stills was a big deal & it requires the best picture quality.

The Yi 4k is a brick, doesn't have 1920x1440, & wouldn't fit in the Feiyu. While it has effective image stabilization & high quality, it should be considered a full size camcorder.

The hero 4 session has an inferior picture to all the full size 'pros. The hero 5 session costs as much as a full size hero 4. The sessions don't fit in the Feiyu mini 3D.

The hero 4 black does 4k 30fps but has no viewfinder. The silver has the viewfinder but does 4k in 15fps. Lions have never ever regretted not having a rear viewfinder on an action cam, not even enough to bother using the wifi preview or wiring an offboard screen to it.

Gopro is still the only one offering 1920x1440, the solid gold format & the only format lions ever used. The 1920x1440 format was the only way to extract stills from video & stabilize without cropping.

The hero 4 was the last one which fit in the Feiyu.

The hero 5 achieves image stabilization by cropping & it's not effective.

The hero 5 is bigger & heavier than all the other 'pros, on account of waterproofing. All the corporations are building waterproofing into every gadget because water damage is a big cause of returns.

The full size 'pros are as light as the sessions if powered without a battery. There are many conflicting rumors about how to power a pro without a battery. The problem is the current generation no longer understands ohms law.

There was a very limited supply of hero 4's at $300. That price was a steal for a 'pro.
Posted by Jack Crossfire | Jul 09, 2017 @ 02:08 AM | 15,192 Views
The truck finally got a dual battery setup with polarized Dean connectors. This didn't require a fuse. The problem was having live, exposed contacts when only 1 battery was used. For the top connector, the solution was terminating it with another Dean connector with the terminals wrapped. The bottom connector doesn't have a cover.


To plug in the batteries, the top connector must be covered & the bottom battery must go in 1st. Then the top battery can go in. To remove the batteries, the top connector must be unplugged & covered before removing the bottom battery. If the bottom battery is unplugged 1st, its live contacts are right next to aluminum, causing a fire after the explosion.


This arrangement with water, speaker, shirt, & polecam used 7166mAh to go 12.5 miles. It was an extraordinarily bad 573mAh per mile. The last mile was hauling food. The newest battery once again discharged more than the oldest battery. Its maximum range would be only 16 miles. The water was drained throughout the 1st 7 miles.


Replacing the aluminum with plastic angle rod is a leading theory, but the lack of shock absorbers may be sapping energy.
Posted by Jack Crossfire | Jul 09, 2017 @ 12:17 AM | 16,088 Views
Polecam with 808 #18 keychain cam (2 min 24 sec)



So ordered the smallest, cheapest $30 camera available for the polecam. It turned out to be the 808 #18 keychain cam from 5 years ago but this wasn't labeled on the amazon & for someone who lived 40 years ago, it was hard to believe something that obsolete was still being sold. Progress has slowed immensely.


Techmoan already moaned about how horrible it was & how great the mobius cam was. Its 1st drive was with 2 batteries, so a direct comparison with the stability of the gopro wasn't possible. It was stable, but still wobbled. It fell over once because of a curb. Would actually say the increase in stability was negligible. The vehicle & pole are so much heavier than the camera, it's probably not worth using a keychain cam for any reason besides longer recording time.



It recorded for exactly 1 hour, but could record for many hours by soldering in an external battery. Now, the mobius cam is $70 & roughly the same size, but it was already clear that polecam would be the only form of videography from now on, whether it was crusty vlogs or cinematic shorts. There would be no reason to use a micro camera.
Posted by Jack Crossfire | Jul 07, 2017 @ 03:14 AM | 3,208 Views
So the lunchbox was loaded with 2 batteries, 20oz of water, a shirt, speaker, cheap camera, & phone. The headlights were off. It went 5.65 miles at 9min/mile, 5.85 miles at 8min/mile, & .3 miles hauling burritos. The 5.65 miles took 3111mAh or 531mAh/mile. The 6.15 miles took 3435mAh or 558mAh/mile. So if it drove at 9min/mile, it would probably only go 17 miles compared to the previous lunchbox going over 20 miles with the headlights on. Another 2 battery test without water bottle is needed.


The other tests without water bottle were with 1 battery, a shirt, speaker, phone & no headlights. Those were around 400mAh/mile. The range would be 22 miles. The aluminum should be replaced with plastic. The tires should be locked to the wheels.


Given the low current of these vehicles, 18650 cells may be a better power source.
Posted by Jack Crossfire | Jul 03, 2017 @ 02:28 AM | 2,751 Views
Polecam 3 (3 min 47 sec)



It lasted 4 years. While riding on polecam 3 after finishing recording, it flipped backward & crashed into the street. The pole amplified the impact speed like a baseball bat. Lowering the lunchbox didn't make it as stable as hoped. A heavy payload & polecam made it quite undriveable. The polecam alone made it less stable, but it still managed to drive 9 miles. The string still loosened after 5 miles & had to be retightened.


A gopro sized cam 40" above street level, with no enclosure, is the maximum for the lunchbox to be driveable. The height wasn't unbearable. In fact, this is a popular height for many productions & it's taller than all the single women of lion age, today. A keychain cam might go higher, but the need to duct tape 2 carbon fiber rods & add extra battery power might negate its weight.


The lion kingdom never paid for a camera for 7 years. The pace resumed last month, with the cheapest still photo camera available. After destroying a few in quad copters, 7 years ago, it was decided there was enough value & it was long enough since the last camera got destroyed to give them another go. Despite being 3 years obsolete, the picture quality got rave reviews compared to any modern phone cam.


There won't be a gopro replacement for a long time. The brushless gimbal may remane dormant. The gopro was dormant for most of its life, with only sporadic sessions attached to a brushless gimbal or a vehicle. Because the view from the polecam is so much better than street level & the gopro size is too unstable, a keychain cam may suffice. The only way a gopro replacement could materialize is for a handheld gimbal movie or if there was a way to protect it without a full enclosure.
Posted by Jack Crossfire | Jul 02, 2017 @ 05:34 PM | 2,143 Views
Replacing the knots with clover hitches & trucker's hitches got polecam 1 a lot more rigid. The entire rigging became a single length of string. It was about as rigid as solid carbon fiber. The mane problem with solid carbon fiber is the attachment points would have flexed. It really is a problem only 3D printing or multi axis milling could solve. A 3D printed coupling would have then been heavier than string.


Experience & SpaceX photos have revealed you can't drill small holes into carbon fiber. Loads applied to it have to be spread over a large area. It can only be bonded to adhesives.


The video was as stable as a pole cam could get. The rigid pole didn't oscillate any more than the steering did on its own. The string dug into the plastic & started loosening anyway. The gopro needs heavier string, but this requires removing more material. Because of the need for stabilization, a long form video would be low definition, so it would be better done with a pinhead camera.


Polecam 2 (3 min 32 sec)

Posted by Jack Crossfire | Jul 02, 2017 @ 02:54 AM | 2,402 Views
Polecam 1 was a failure. The rigging came loose, allowing it to oscillate. The erratic steering amplified the problem. Even a perfectly rigid pole might have oscillated.


Polecam 1 (1 min 57 sec)

Posted by Jack Crossfire | Jun 28, 2017 @ 11:48 PM | 2,592 Views
It's quite clear that the lunchbox steering has been hunting, ever since the encounter with Asian capitalism. A rear wheel was damaged, so it bounces up & down. This makes the gyro oscillate, which makes the steering erratic. Its damaged state is a good time to try more aggressive techniques of locking the tires to the wheels.


The lion kingdom started seriously considering installing a camera & sound system for making eye level vlogs from the vehicle. 10 mile runs can get extremely boring & a lot of thoughts come through a lion's mind. It would be a much smaller camera than a gopro, suspended by a guywired carbon fiber rod. There are now lots of keychain cameras advertising "1080p" for under $40. Wireless headset microphones are now under $50.


Then of course, there's the DJI Mavic. There is a way to make a 1 handed remote control for it & fix the altitude so it follows an athlete semi autonomously. It would be 20 minutes at a time, but enough to capture a speed mile. There wouldn't be a way to drive a ground vehicle simultaneously. The Mavic would need to accurately track a speed. For $1000, the video would be watched by 20 people.
Posted by Jack Crossfire | Jun 25, 2017 @ 02:55 AM | 3,506 Views
The day had finally come to install short circuiting switches on the Mastech. Many circuits were fried because its current limiting was set too high. It was too much trouble to unplug the circuit & plug in a short circuiting wire to set it.


Despite looking simple from outside, the front panel is packed on the inside. There was only 1 place to squeeze the switches in. The LEDs had to be sandwiched between the switches & the plastic. At this time, another desire emerged to have switches for turning off the individual outputs without turning off the manes, but this would have been a much more incremental benefit than the short circuit switches.


With it all installed twice, the switches pointed at the current dial when they were shorting & pointed at the voltage dial when they were open. This was the most intuitive orientation. They worked very briefly, at low voltages & all current up to 5A. When the voltage was set to 30V, the switches quickly failed closed.


The switches open by a spring force which the human has no control over. The human can merely press the spring to make contact, but the spring must break contact by its own force. The spring had arc welded to the contact. It could be broken apart & reassembled, for the most part. Despite being rated for 6A 120V, the switches still failed at 30V 5A.


The best the internet can come up with is 120V AC ratings being equivalent to 14V DC, because in AC there is a zero crossing after 8ms to break the arc while in DC, the arc can continue. While the power supply limits current when quiescent, there is a very high inrush current when short circuiting it. The Chinese must have encountered the same problem, said "f*ck it" in Chinese & left out the short circuit switches.
Posted by Jack Crossfire | Jun 25, 2017 @ 02:09 AM | 3,412 Views
The lion kingdom long dreamed of a switch allowing a heat gun to blow cold air. It would cool hot glue. The deed was finally done. The wires were not intuitive. The big red & black pair didn't power the heating element, but probably powered the thermocouple. It was the tiny black pair connected to CON1.

Unfortunately, it takes a very long time for the heating element to cool off. The switch has to be off when it 1st comes on or it'll take 30 minutes to blow cold air. It does indeed cool hot glue.
Posted by Jack Crossfire | Jun 24, 2017 @ 03:48 AM | 2,782 Views
The story sounds great until you realize in order to reuse the 1st stage, they have to throw away 34% of the payload, according to Kiwipedia. There are no dual geostationary satellites at a time or payloads of opportunity like the Arianne 5.

Given this fact, let's calculate the cost of launching the same mass with reused 1st stages & expendable 1st stages. The shotwell said it costs "less than half" to reuse the 1st stage, which we'll assume means half. The 1st stage is 2/3 of the total cost, so that gives a total cost of 2/3 / 2 + 1/3 as the cost of a flight proven booster.

So the 1st launch of 1 payload costs 1 for each system. The later launches cost .667 for flight proven & 1 again for expendable. With these parameters, the cost/lb for flight proven approaches but never goes below the expendable system. The problem is the discount for a flight proven rocket exactly matches the reduction in payload.

As soon as the flight proven booster gets anywhere below 1/2 the cost of a new booster, it saves more than the reduction in payload & it becomes favorable. Just reducing the refurbished cost to 40% of a new 1st stage would barely start breaking even after 7 launches. If they miraculously got it to 10% of a new 1st stage, they would start saving huge amounts of money after 3 launches.

Even in the miraculous case, they wouldn't start saving money until 3 launches. So far, they've only gotten 2 launches from the reused 1st stages, so they're losing a huge amount of money. The future is still heavily dependent on new Falcon 9's being much cheaper than other rockets, with the hope that someday they can reuse just 1 booster for a whole year with much lower refurbishment costs.
Posted by Jack Crossfire | Jun 24, 2017 @ 02:19 AM | 2,964 Views
So Heroineclock II's mane problems were it had an offset crystal & it was calibrated from a computer RTC which itself was offset. It gained 5 minutes over 77 days. Its internal clock increments 250 times per second. Thus, it needed to subtract 5 * 60 * 250 ticks every 77 * 24 * 60 * 60 * 250 ticks or 1 tick every 22176 ticks.

Unfortunately, it had an existing trim factor of adding 1 tick every 10300 ticks, so the 2 trim factors need to be combined. The trick was to multiply 22176 * 10300. This predicts the existing trim factor adds 22176 ticks for every 22176 * 10300 ticks & the new trim factor subtracts 10300 ticks for every 22176 * 10300 ticks. Thus, the total change in ticks every 22176 * 10300 ticks would have to be 11876 or the addition of 1 tick every 19233 ticks. The new addition is less frequent than the old addition, so it satisfies the need to slow the clock down.

We still need to reduce the 19233 to 19230 make sure the clock doesn't run slow.
Posted by Jack Crossfire | Jun 22, 2017 @ 11:05 PM | 2,238 Views
After a few more days, a few hundred electrical & mechanical connections, the container was fastened. It's not as trivial as it looks. It hauled 3.6 lbs without flipping over. The wheels spun quite a bit on any uphill & it high centered. Because all the wheels are now fixed, it can now be supported by 2 front wheels & 1 rear wheel, leaving 1 rear wheel to spin.


The next step was installing a carbon fiber handle. After much debate, the decision was made to not make the handle removable. This limited objects to much smaller dimensions than the maximum, but clearly just as big as the previous container. The holes were cut just big enough to press fit the handle in. If they were expanded & cotter pins installed, the handle could be removable.

With the amount of material now removed from the original lunchbox, it was hardly worth its full price. The 1st drive was 6.8 miles. 3 miles had headlights & payload. 1 mile was at 10mph. It used 2777mAh.
Posted by Jack Crossfire | Jun 18, 2017 @ 08:17 PM | 2,913 Views
After 3 years, the lunchbox finally got run over by an H1B, as expected. It confirmed H1B's are indeed the lousiest drivers. It is a great irony how the most advanced software & the most money in the world is made by people who grew up with no modern appliances, still count in units of 100,000 instead of thousands or millions, & still eat with no utensils.

Didn't expect him to gun his $80,000 SUV, but he did. The human easily jumped in the middle of the road but the tiny, inconspicuous lunchbox didn't stand a chance. Amazingly, it still ran. There were some minor cracks, a broken spring & some bent plastic parts, but nothing that couldn't be worked around.

The lunchbox could easily have been put back on the road in its previous form, but it was a good time for the next long awaited mod. After much staring at walls, it was decided to replace the suspension with wood & replace much of the chassis with angle aluminum. This would lower the payload down to the wheels. Ideally, the wheels would have been raised higher on the existing chassis, but this would lower the battery down to the road.

Most of the chassis was ground off. The aluminum had to be ground away to make room for the motor. The aluminum ended up much heavier than ideal. There was enough room for a later step to expand the payload.


After 3 days, it was mostly complete. The suspention had to be rebuilt several times to get the measurements right. I bolts were key, but the 4-40 eye...Continue Reading
Posted by Jack Crossfire | Jun 16, 2017 @ 04:25 AM | 2,771 Views
Didn't realize Microsoft discontinued its flight simulator work in 2008. Considering the improvements in graphics hardware, the flight simulator was no longer the most immersive experience possible. What people want is immersion. The most difficult material to render accurately is human characters while the easiest is stationary landscapes. That limited the most immersive games before 1991 to flight simulators.


It was a miracle in 1991 when the 1st 1 mile resolution satellite photos started getting overlaid in the Aviator program that ran on Sun workstations. The immersion wouldn't compare with today's animated character games.
Posted by Jack Crossfire | Jun 13, 2017 @ 05:04 PM | 2,710 Views
With a 9 year old monitor & 7 year old PC, the pressure has mounted to do yet another upgrade. A modern monitor would have twice the resolution & much better color, for a lot less money. The pictures you see would look a lot better, rather than having erratic black levels & dull colors. The graphics card is 11 years old but was top of the line for it's time.


Besides the definite improvements available in picture quality, modern processors claim massive gains but no clockspeed increase. The 7 year old PC is a 3.2Ghz quad core AMD overclocked to 3.8Ghz. What does newegg show as the top end but 5 year old 4Ghz chips. The benchmarks show the Intel quad cores 3x faster & AMD octocores 2x faster than the old AMD, but benchmarks don't easily correlate with video playback.


The Macbook which runs Cinelerra 10% faster than the PC is only a 2.5Ghz Intel. 4k video editing on the top end Macs in the Apple store looked pretty slow. Performance gains may depend heavily on memory speed, which is independent of CPU speed. The 2.5Ghz Macbook may be very close to the 4Ghz top end, because of memory speed. Because of the amount of 4k video showing up, modern systems must be able to play it without hardware acceleration, at full resolution & bitrates. The old PC can decode the full 4k but only blit it to a reduced resolution window & decode it from a reduced bitrate. Heavy changes in detail make it studder.


Part of the upgrade would be returning to...Continue Reading
Posted by Jack Crossfire | Jun 09, 2017 @ 02:14 AM | 3,624 Views
Remember 4 years ago when drone delivery was just around the corner & Jeff Bezos was investing the billions in it that he now invests in Blue Origin? What about drone delivery which moves your luggage to the airport so you don't need to wait in line?
Posted by Jack Crossfire | Jun 04, 2017 @ 10:15 PM | 3,041 Views
Spacex vs spacex (3 min 22 sec)


You can infer more about the NROL-76 payload by comparing its launch against CRS-11.

The NROL-76 booster went to a much higher altitude but equivalent speed. NROL-76 was a slightly lighter payload, as shown by the faster liftoff. It had to burn a lot more fuel to land the 1st stage from the higher altitude, despite the lighter payload. CRS-11 was a 15,000 lb payload. 9000 of a Dragon mission is the Dragon system alone. The mass of the payload fairing is unknown, so it can't be directly compared to Dragon.


Estimating the mass of NROL-76 requires comparing the time it took to clear the tower to another communication satellite. SES-10 took off ever so slightly slower than NROL-76, so NROL-76 was a hair below 11,000lbs. The difference in speed was only obvious with Dragon launches, showing how the Dragon system was much heavier than a communication satellite with its fairing.


After launch, NROL-76 was detected in a 248mile circular orbit with 50deg inclination. There was no reason to go to the higher altitude besides concealing its orbit.



Falcon 9 nrol76 landing stabilized (3 min 32 sec)
...Continue Reading