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Archive for October, 2017
Posted by Jack Crossfire | Oct 31, 2017 @ 01:32 PM | 4,400 Views
Berkeley run 3 (5 min 18 sec)

Ever so slowly getting closer to the perfect video. Figured out by this point, no-one cares about the VR mode.
Posted by Jack Crossfire | Oct 29, 2017 @ 12:23 AM | 4,745 Views
Another go at fixing the steering oscillation through PID gains & gyro padding led nowhere, so the next theory was back to the culprit of the Ruckus oscillation: worn bearings. The plastic bearings were definitely loose & the lunchbox was much more stable when it was new. It'll be another long, slow UPS delivery to do what used to take a run to the hobby shop.

Then came the revelation that the right front inside tire was completely ground off again & the left front inside tire was wearing out much more slowly. The experiment in lowered suspension was still a disaster. There was a slight boost in efficiency, but they were now off on only the right side. It wasn't the camber or the toe in. This is a real stumper. Those tires are expensive.
Posted by Jack Crossfire | Oct 28, 2017 @ 12:49 AM | 4,743 Views
The quality is hopeless, compared to any other method. There's no way to survive watching a movie in VR goggles. Tried a phone with 2560x1440 resolution. The screen was chopped off in the corners & the screen door effect was more obvious than the 1920x1080 phone. As the pixels get smaller, the proportion comprised by the gaps grows. Only objects behind the screen are viewable. Objects in front of the screen are too close to your eyes, in the goggles.

They do have a niche. They're flat out, the only way to view 3D color images on a phone & they're cheaper than all the other methods. Medical visualization might benefit from this kind of portable 3D imaging. By the time smartphones appeared, the 3D craze was gone. Phone support for polarized glasses only lasted for the 1st few years, on some rare models. There are no shutter glasses with IR dongle commercially available for phones. The era of shutter glasses is over.

Lions are some of the few animals to have watched movies using shutter glasses as well as polarized glasses. The shutter glasses for IMAX were real painful & left a mark on your forehead. They had a small amount of ghosting, even with film. They had extra speakers in the goggles which did nothing. The only movies lions saw with shutter glasses were Space Station 3D & Titanic: ghosts of the abyss. They were quickly replaced by polarized glasses.
Posted by Jack Crossfire | Oct 26, 2017 @ 06:12 PM | 4,537 Views
The lion kingdom hasn't finished Passengers yet, but already knows how it ends. It's visually stunning & makes you think about the logic, but otherwise is a disaster on autopilot. It would have been infinitely better if the heroine was revived by an accident of fate rather than the man deciding his pleasure was more important than her survival. The importance of the man's desires is the premise of the entire movie. If you don't agree, it's a 2 hour wait until she finally finds out he woke her up on purpose.

It would have also been better if the heroine woke the man up, but this is not 1999 anymore & audiences are a lot more conservative.

The days are long gone when lions thought you could figure out someone was your true love just from watching her videos & writing. The idea of popping a woman out of hybernation & instantly having her fall in love with you, with no arguing, health problems, stepkids, or ex husbands, is insane. In reality, they would spend their lives on opposite ends of the ship. If no-one else is there to witness it, there is no economic benefit or social status to gain from the man & relationships don't happen. She certainly wouldn't have been in love with a guy who needed upgraded breakfasts from her gold plan.

Surely, they would have had kids & the kids would have continued to their destination, continuing their lives as it were, but the movie doesn't end that way. Perhaps it was a superposition of the audience's values that...Continue Reading
Posted by Jack Crossfire | Oct 23, 2017 @ 12:53 AM | 4,360 Views
EEVblog #1032 Part 4 - John Kenny Keysight Interview (32 min 14 sec)

This episode had a few good nuggets.

Home runs are few & far between when designing new products. It takes a lot of failures to get a win, no matter how good you are. Unfortunately, our industry is structured as 1 startup per product, rather than a bunch of products directly under 1 venture capital fund, so there's a massive overhead of breaking up & reconstituting new teams just to get the point of creating the failures. Many home runs fail because the extra step of reconstructing a new team failed.

The best easter egg in a device with no display is a message in morse code that's sounded in any way it can make sounds or blinked through LEDs.
Posted by Jack Crossfire | Oct 21, 2017 @ 02:08 AM | 5,549 Views
On the day the RS-25 & the BE-4 were both test fired, Musk's comeback was a picture of his shoes in front of a bunch of jack o lanterns.


Does he dress up at home? Based on the spynet, he wasn't at home. The pool didn't match, but it wasn't much different than his 1st mansion.


Bet you didn't know Elon Musk was slowly buying up an entire hillside on Chalon Rd, Bel Air. Is he going to build a launch pad? Is he going to build a massive transit center for his tunnels? Is he trying to get a better view of his rockets landing? Is he buying more room to store his toys?

It's probably more practical, like storing wealth in real estate. It's currently $100 million. It's not a very diverse portfolio, but more practical than a house in Idaho. To be sure, he doesn't really have $20 billion in cash. It's private equity valued at whatever the fed deems necessary to ensure total employment, but worthless if he sold it all at once.

Looking at the photo of the shiny shoes by the pool, the lion kingdom wondered how someone not much different than the rest of us could achieve so much more. He's not supremely intelligent like Steve Jurvetson, but only an incremental step above the rest of us. He's not very good at giving speeches or interviews. His highest formal education was 2 bachelor's degrees from UPenn, in economics & physics.

He has above normal intuition about problems & finding ways to solve them by rearranging existing technologies, but not by much. His 1st company was founded with $28,000 of his father's money, or $280,000 in today's doll hairs. Theoretically, his father also paid for all his education, leaving him debt free. Even then, if the lion kingdom had $280,000 of dad's money, it would probably go in a bond fund.
Posted by Jack Crossfire | Oct 20, 2017 @ 12:16 AM | 5,403 Views
This works quite well, for what it is. The iPhone 6+ gives 960x1080 in each eye, which is actually higher than the lion kingdom's 1st x86 computer which did 800x600 . The Samsung Galaxy 8 would give 1480x1440 in each eye, high enough to replace a Macbook air. The LG Tribute would give only 640x720 per eye.

The computer generated 3D scene in Goog Cardboard is quite convincing. Unfortunately, it's not so easy to get 3D videos which work in it. A rectangular 3D movie can disregard which way your head is pointing. A spherical movie needs to look behind different objects based on where your head is pointing.

The mane limitation is lack of software, now that the VR craze is over. Nothing works on the LG Tribute which is actually light & cheap enough to use in the long term. There's no way to play your own spherical photos on it. Youtube videos don't play on it. Any software needs a wireless gadget to replace the touchscreen.

Its mane use so far is viewing someone else's stereo rectangular photos in color. It's quite an improvement over the anaglyphs of 15 years ago, despite much lower resolution. A 10 year old lion would have gone crazy over them. Unfortunately, no video player is smart enough to wait for a magnetometer trigger to start playing, so it's already over by the time you get the goggles on.

At $11, it's not worth writing a custom app to make these goggles more useful. If they were really worth anything, the biggest payback would come in the...Continue Reading
Posted by Jack Crossfire | Oct 18, 2017 @ 03:59 PM | 4,694 Views
Stabilized spherecam at 10mph & timelapse (1 min 50 sec)

1st motion stabilized spherecam footage. No more black borders.

It could almost pass for usable. There was a lot of math in rotating the spherical image. The solution was in an obscure library


For motion tracking, the transformation needs to be centered around a movable pivot, so it really needs to do 3 transformations. It first moves the pivot point to the center of the image, then performs the requested transformation, then moves the pivot point back to the pivot point. The fastest solution on a modern CPU is applying 3 matrices to each pixel instead of copying the image 3 times. Combining the 3 matrices through multiplication didn't work, so it's a very slow process.

Stabilized spherecam with VR mode on (1 min 50 sec)
...Continue Reading
Posted by Jack Crossfire | Oct 15, 2017 @ 12:46 AM | 4,735 Views
Spherecam did its 1st 6 miler with some hops to 10mph. The steering was extremely erratic. The roll cage didn't have to be used. Steering oscillated enough for the video to be totally unusable without stabilization.
Posted by Jack Crossfire | Oct 14, 2017 @ 05:13 PM | 4,646 Views

The ones he answered weren't that bad. Impressive that they developed a new alloy for the turbopump & claim scaling the engine up will be a very simple process. Starting with a subscale engine may go down as one of those brilliant decisions which got us to the stars or might not, but it does require tooling for 2 engines. It's hard to believe the entire development programs for the F-1, RS-25, RS-68, RD-180 were done with the full scale engine.

Other mane points:
Header tanks will have such low heat leakage, they're planning on keeping them subcooled for all those months without active cooling.
The nose will be pointed towards the sun, so no view of Mars getting big in the window.
Development program will use full scale BFS's doing atmospheric hops like the grasshopper.
He expects to exceed airline safety because airlines only have 2 engines while the BFS will now have 3. It's more complicated than that, but classic Elon.
The RCS thrusters are based on the Raptor combustion chamber rather than a clean sheet design like the Dracos.
Posted by Jack Crossfire | Oct 14, 2017 @ 01:01 AM | 5,140 Views
Spherical video rover (2 min 56 sec)

It utilized the roll cage extensively. Acceleration had to be as slow as possible & it needed lots of ballast. It only fell over axially. It's not useful for high maneuverability. There's no hardware stabilization, but the equirectangular mode isn't very jarring. In VR mode, it would look awful. The equirectangular mode got a better response from viewers, so they'll just be uploaded in this mode.

A spherical cam can raise its height mathematically even if it isn't on a pole, but quality suffers. Another overhaul of the firmware got the acceleration to where it didn't flip over with the cam on. Starting the motor takes a very complex state machine, but it's amazing just how far you can go with sensorless motors. Steering & bumps are still going to be problematic.
Posted by Jack Crossfire | Oct 12, 2017 @ 04:12 PM | 4,747 Views
Stanford students during the longest economic boom were philosophizing a lot more than during the recessions. It was much more crowded at 8pm than it was, many years ago. Steve Jurvetson was mingling with students with stars in their eyes, supposedly members of a class he taught. This was the generation which would fill SOMA in the coming years while the rest of us drove the taxis their mobile apps dispatched.

He swaggered into the parking lot, taking a picture of the line of space fans which would disappear forever into his iCloud account & never be tweeted of course. Lions supposed as he got older, Jurvetson had to diverge from the wild cards like SpaceX which made him famous to more on target startups in pizza delivery & philosophy. The days of guys programming registers in basements were over. A modern entrepreneur was a philosopher. Steve was now keen on fitting in that crowd.

The presentation was the standard boilerplate. Shotwell seemed a bit more specific than past videos. The questions were the standard big pictures, nothing technical, manely from Steve & nothing from the lion. Though there was no new media on the BFR nor the layout of the 1st stage engines, she did say the 1st full size Raptor was under construction, a new factory was going to be built rather than converting the Hughes factory, & they were now heavily focused on BFR development.

The amount of dialog & urgency on such a far fetched spaceship was most...Continue Reading
Posted by Jack Crossfire | Oct 10, 2017 @ 11:57 PM | 4,505 Views
A 3rd rework put the camera as high as it could go. This required putting the fan under the camera & pointing the soft lens forward. A bit more effort could rotate lenses by rotating the entire assembly. Because the fan was underneath, the only way to give it airflow was to mount the protection farther away. It's not protected from a diagonal fall, but is fully protected from axial & sideways falls. Fortunately, no vehicle has ever flipped over diagonally. They've manely fallen sideways. The gopro death was an axial fall from accelerating.

It's reasonably unobstructed. What happens next is already known from decades of making camera systems. The test movie is too shaky to be useful so stabilization in the spherical domane is developed, over months & years. For now, the frat houses provide stabilization of spherical videos when played in a viewer but not equirectangular mode. There's unoptimized, 2 year old source code for doing it with mobius transforms.

How times have changed from 20 years ago when any idea had a recent example in source code.
Posted by Jack Crossfire | Oct 08, 2017 @ 09:00 PM | 4,582 Views
After much planning & other tasks needing the camera, the imagination once again became aluminum & duct tape. It's 1ft lower than last year's pole cam. A minimum amount of protection from falling on the lens was devised, which would obstruct as little of the view as possible. The good news is the current generation is used to seeing equipment & seams in a spherical photo. The camera needed more spacing below the cross to avoid being totally obstructed. A gopro could be mounted above the cross.
Posted by Jack Crossfire | Oct 08, 2017 @ 03:24 AM | 4,595 Views
Making a modular, elevated camera system for a rover has been as problematic as it was for copters. Right away, the h-king is too small for a pole cam. The pole needs to be lower than last year's experiments because the Gear 360 is heavier & experience showed the need to protect it. Any method of protecting the sphere cam is going to obstruct some of the frame, but a method using 2 sticks might protect it from a fall in any direction.

The sticking point is now attaching the pole to the vehicle. A sheet of material bolted to the vehicle is a real pain to install. A metal X is a leading contender. Then, the pole is simply lashed to the vehicle handle. It won't need guy wires because it's lower. Stabilization is nowhere on the radar. Getting good video has always required a larger vehicle than the budget allowed.
Posted by Jack Crossfire | Oct 06, 2017 @ 03:24 PM | 4,871 Views
20 years after the lion kingdom hatched the idea, someone finally used a 55" TV as a computer monitor. Doubt it'll last, because it's immediately obvious that he can't see the entire screen behind the clutter. There's no airflow. He has to sit too far away to see normal fonts. The DPI is 100. Not all programs scale to larger DPI, so 55" is the smallest 4k display which can display legible fonts.

It's cheaper than the 30" monitor lions have been using since 2008. A younger lion would have sprung for it & watched movies in fullscreen, in a dark room, in 1 shot. An older lion is concerned with practicality & only watches segments of movies in a window. The time spent watching movies in 1 shot has long been dedicated to the commute.
Posted by Jack Crossfire | Oct 06, 2017 @ 01:31 AM | 4,368 Views
2 years after the Accucel's 1st surgery to break out the balancing header, it was time to replace the buttons, which had manely stopped working. They graciously exposed all the buttons on a header. It merely entailed breaking them out on a very long ribbon cable. The 12 year old buttons from Heroineclock 1 were installed. They were heavily rusted. 2 of them didn't work. Fortunately, had another 2 buttons from a camera remote of long ago. They used to be a 30 minute run to Radio Shack. Now, the only way to get more of those is a 2 week order.

The Accucel's LCD is still broken, but hasn't degraded. It may end up being reverse engineered & replaced by a converter to drive a larger LCD. There's no evidence of what part it was, but it only has 4 data lines. It's been such a waste of time repairing this $35 antique, the process might as well keep going.
Posted by Jack Crossfire | Oct 01, 2017 @ 03:45 PM | 4,593 Views
In documenting airplane interiors, it quickly became obvious just how bad the Gear 360 is. Basically, it's useful for spherical video but only photos in a pinch.

Vintage F-16 cockpit:


Vintage C-130 cockpit:



C-130 cargo:



Vintage airplane cockpits are quite dear, because once they're scavenged & sent to the boneyard, they're gone for good.

The instrument details are completely lost, except for the flight engineer panel directly overhead, but it was sheered by the lens gap. The Gear was on a tripod with the intention of mounting it stationary in the middle of the cockpit. In reality, it would have been better on a handheld pole. The tripod was never used. Shots from the 4 seats close to their respective instruments would have been the best this camera could get.

Cargo planes have detail above & below, so something is always sheered. Objects are close & closer, making the parallax always sheer something. Fighter planes have detail only below. It would have been best to have the lens shear bisect between the canopy & instruments. Even better: have the N & S poles face the sides. There's still no obvious way the Gear 360 could have resolved the F-16 instruments.

The best quality sphere photos are still taken by a guy shooting a DSLR in every possible direction. It might be on the end of a pole, with exposure bracketing. The next highest step is a robotic mount. The next step is a Gear 360 on a pole. For airshows with large crowds waiting in line, there are probably better ways to utilize the Gear 360 like pointing it in different directions to defeat the sheering line.
Posted by Jack Crossfire | Oct 01, 2017 @ 12:57 AM | 4,575 Views
Kind of fitting after China declared its J-20 stealth fighter operational, the F-22 broke down during the demo. It flew much closer to the audience than the fleet week demo, which made it much harder to get in frame. It was very frustrating to hear it more than see it, since it was never in frame when you looked in the viewfinder & already gone by the time you looked away from the viewfinder. All the tents made it impossible to see before it was right in front.

After only 4 passes, it malfunctioned & had to land. The audience immediately left without waiting for the heritage pass. Being an airshow announcer must be a hard job, starting the narration while the seats are still empty, announcing hours of demos no-one cares about, & announcing the heritage pass after the F-22 broke down, while watching everyone leave.

Other than the mane attraction, the military cargo planes were all in Puerto Rico & there was no Thunderbird demo. The audience was clearly not having any of it & just waiting for the F-22.