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Posted by Jack Crossfire | Feb 20, 2018 @ 04:58 PM | 1,177 Views
Hands-On with Skydio R1 Autonomous Drone! (22 min 3 sec)







Really impressive demos from Skydio in Redwood City. Quad copter startups have been hit or miss & it looks like the same pile of plastic scrap that every startup besides Apple produces, but what they showed here was exactly what I wanted to do for years, with ground vehicles. It looks like it could really navigate most of the mobs I have had to navigate manually. They showed it briefly flying in front of the athlete, despite not having prior information about where the athlete was going. The flight time is undoubtedly very short & the $2500 is almost 1 month of rent.  As a $2500 consumer quad copter, it has no chance, but it would have a chance as a kit allowing developers to add autonomy to ground vehicles.


They're the 1st to consolidate a lot of the bits of research that were done in the vicon rooms for the last 10 years, into a complete product. They emphasized the demo of the fixed wing flying in a parking garage.  It's the 1st time anyone has shown the NVidia TX1 doing anything besides raising its stock price.


Not sure how well it would translate to a ground vehicle, because a ground vehicle needs to stay on a certain path. Prior knowledge of roughly where the athlete was going & where the path was might allow it to do the job. Suspect GPS has not improved enough to stay on a path without some other input.


It wouldn't translate well to a Casey Neistat application. His interest is...Continue Reading
Posted by Jack Crossfire | Feb 20, 2018 @ 04:08 AM | 1,507 Views
Obsolescence has been a big problem for reusability. They haven't been able to recover any more Falcon 9's lately, because of the plan to switch to block 5. If a product evolves too fast, there's no need to ever reuse it. They'll retire the 1st reusable Falcon 9 after only 26 launch attempts.


In 4 more years, they want to have the BFR doing all the satellite launches, but after Falcon Heavy launched, Elon sounded eager to continue improving the old Falcon 9. So maybe in another year, it'll be a Falcon 9 with longer 2nd stage that replaces block 5 & makes recovering block 5 worthless because of obsolescence.
Posted by Jack Crossfire | Feb 17, 2018 @ 02:45 PM | 1,855 Views
http://abc7news.com/technology/sky7-...ameda/3097474/

Can imagine the interview there would go like "Why do you want to work here instead of SpaceX?" followed by "Can you handle not getting into SpaceX?" But there are a lot of people who just want to build rockets for the sound, the power, & the thrill of putting anything in space rather than to solve problems or change the world, or be a viable business. In this case, it's probably good enough to get any employment they can find.

https://arstechnica.com/science/2017...0-hour-firing/

Of course, searching for the Astra rocket gives you the Ad Astra startup which has been trying to develop new engine technology for 20 years. Apparently, the biggest problems with this kind of engine are manetaining a vacuum to test it in & generating enough power to feed it.
There is no affordable space platform with the generating capacity or way to reach orbit cheaply enough to try many prototypes. Just reaching a 5 minute firing took half a century of extremely slow iterations. It's another example of what a revolution a rapidly & fully reusable rocket would be. If launching a 1/2 million lb nuclear reactor & daily iterations of engine hardware suddenly took a rational amount of money, engines like this could be tested in years rather than centuries.
Posted by Jack Crossfire | Feb 12, 2018 @ 12:17 AM | 2,250 Views
Despite the billions of other videos, there was still room for improvement.


Falcon Galactica (1 min 1 sec)



Falcon Heavy compositing (0 min 35 sec)
...Continue Reading
Posted by Jack Crossfire | Feb 07, 2018 @ 06:32 PM | 2,671 Views
The final shot as he heads to the asteroid belt. If I did it, it would have been a star heroine, but it shows how in times of giant leaps for mankind, just like in dating, we are all conservative.
Posted by Jack Crossfire | Feb 07, 2018 @ 12:12 AM | 1,286 Views
A bit ironic that the thousands of useless animations you have to watch to get a phone to turn on were written in Silicon Valley while the utilitarian firmware which brought us affordable access to space was written in LA.
Posted by Jack Crossfire | Feb 06, 2018 @ 05:26 PM | 1,369 Views
Maybe someday after the humans have all destroyed themselves, aliens will discover a Falcon 9 upper stage with a car orbiting between the sun & Mars, with a likeness of Earth's inhabitants in the driver seat, seemingly trying to achieve some vicarious trip. They'll wonder what we could have possibly wanted so bad.
Posted by Jack Crossfire | Feb 05, 2018 @ 02:55 AM | 1,551 Views
Just amazing how much effort went into mounting cameras & painting kapton covers black. They just put kapton bags where the tires used to be. The rumor is all the employees signed 1 of the panels. Most of the effort will never be seen by the public. It definitely wasn't tested in a vacuum chamber. We have a rare look at the pneumatic actuators for fairing separation. Each has its own gas tank to ensure it absolutely fires.
Posted by Jack Crossfire | Jan 19, 2018 @ 02:13 PM | 1,634 Views
20 years after viavoice began trying to push voice recognition to consumers & was an utter failure, voice recognition was rebranded as personal assistants with artificial intelligence & pushed a lot harder for the last several years. Lately, either people have got the Alexia bug or Jeff Bezos has been making a last ditch effort to promote it, much like his last ditch efforts to promote fire phone & kindle before they died. Nowadays, marketing has gotten good enough that you can't tell at all if people really crave something or if it's being pushed.


If there really was artificial intelligence anywhere near intelligent dialog to the level stock valuations reflect, it would have already changed everything.
Posted by Jack Crossfire | Jan 10, 2018 @ 05:36 PM | 2,032 Views
zuma fairing separation (0 min 59 sec)



2 halves are clearly visible in the enhanced uslaunchreport footage. There are 2 gas plumes & the 2 blobs move from right to left as they separate. The only thing you could presume is the bottom half not moving far enough away to clear the payload, but they proceeded with later launches as if nothing happened.

Meanwhile, the FH static fire was reduced from 15 to 12 seconds. The shuttle got 20 seconds, but faster data fidelity probably reduced the need.
Posted by Jack Crossfire | Jan 10, 2018 @ 01:12 AM | 1,947 Views
https://youtu.be/1HVIECDps1Y?t=2m41s


Multiply by 3 & you get tomorrow's Falcon Heavy static fire, the largest static fire since the Saturn V & the largest ever on a pad. There wasn't a static fire of the Delta IV heavy or the Ariane V. The shuttle was static fired only at 1.2 million lbs of thrust. The Saturn V was static fired on a test stand. Falcon Heavy #1 will be tested at 4.7 million lbs of thrust for 15 seconds.
Posted by Jack Crossfire | Jan 09, 2018 @ 05:49 PM | 1,897 Views
Some kids thought it was a block 5 in the final photo. It's ready for some kind of painting. The 1st block 5 is supposed to be #1046. Since block 5 engine testing was still going on recently , it's not visually different from a block 4, & #1044 was spotted in Fl*rida, it's probably #1045.
Posted by Jack Crossfire | Jan 04, 2018 @ 07:14 PM | 2,194 Views
The pattern of CNC milling actually looks like something from an advanced civilization. Perhaps it really did come from aliens.
Posted by Jack Crossfire | Jan 02, 2018 @ 02:11 PM | 3,598 Views
Dreamed about watching the 1st Falcon Heavy liftoff on a TV. Didn't see the engines ignite because the TV started by showing the wrong video. Someone changed it only after it was off the pad. It actually made it off the pad & was doing the pitch program. Then the right booster went out. The other 2 kept going & it strangely didn't terminate as it continued pitching over & Elon's car headed for the water. After the longest wait, it finally exploded. It seemed because the booster was the 1st to be reused from a geostationary mission, the additional stresses were an untested configuration.


Then dreamed about a 2nd Falcon Heavy liftoff which happened many years later because of the time needed to evaluate the failure & prepare 3 more boosters. It actually made it to orbit & the core stage was being shown returning to the boat. It started the landing burn real late & slowed down dramatically. As it neared the barge, it was oscillating a lot more than usual. After it hit the boat, it ended up falling over like an earlier launch & exploding. The extra mass in the center core was an untested configuration much like the earlier launches.
Posted by Jack Crossfire | Dec 28, 2017 @ 11:35 PM | 2,753 Views
The Delta IV heavy was a fascinating rocket, when it 1st came out. It looked like a classic giant movie spaceship when it lifted off & pitched over, revealing a row of 3 widely spaced engines. The space shuttle & Ariane 5 didn't look like classic movie spaceships, because they were obscured by solid rocket exhaust or mostly seen with just center engines after booster separation.


The Delta IV heavy never achieved its goal of economic, scalable capacity. Rather than repurposing the same cheap cores from smaller rockets, it probably matched SpaceX's experience of having to completely redesign the center core just for a handful of missions. Hopefully, making the boosters reusable will achieve better results.


Falcon Heavy will look even more massive when it pitches over. 27 engines making a rectangle of light will look like the rear end of a battlestar or a star destroyer only seen in movies until now. Then, when the side boosters separate & the opposing plumes of 3 engine burns interact, it should be a spectacular airshow.


Despite not coming close to the size of the rockets we once had, these triple core rockets are somewhat fascinating because of the potential to be affordable.
Posted by Jack Crossfire | Dec 22, 2017 @ 02:03 AM | 2,393 Views
So what would have happened if Musk said "Picture of FH payload soon" & it was YOUR CAR on the payload adapter? Are the Calif* license plates still attached? It wouldn't stand the loads if it was supported from the rear & the fairing wasn't wide enough to mount it flat, so it got mounted in a dealer pose.


The mane impact from this is that it's his own personal car which he probably drove many times, not something from a customer or a purpose built payload. It's probably going all the way to Mars orbit with the 2nd stage, so it'll be possible to track. It should be quite a sight, as the employees announce the mission milestones with the boss's car.
Posted by Jack Crossfire | Dec 18, 2017 @ 11:09 PM | 2,632 Views
A routine drive ended as a wheel rolled off. The lack of shock absorbers & shifting of payloads forward must have done it in. If it had just a few more stringers, it would last longer. That caused the tires to wear unevenly.
In this age, 10 years after the 3D printer craze, it's hard to believe there's still no way to make custom wheels.
Posted by Jack Crossfire | Dec 14, 2017 @ 10:22 PM | 2,492 Views
Our 1st & only view of the rebuilt LC40 from above. There's no evidence of the explosion, 16 months ago, nor a crater or burn marks. The mane intrigue is how many buildings are packed close to the launch mount, close enough to feel the exhaust heat & the force of the sound pressure waves. Vandypants isn't built up as much, near the launch mount.


Conventional wisdom is to be able to service the rocket as much as possible when it's on the launch mount, but instead of the traditional arrangement of a hangar far away & a mobile service structure, they've moved all the infrastructure as close as possible, weighing knowledge gained about the blast radius over time.
Posted by Jack Crossfire | Dec 14, 2017 @ 05:59 PM | 2,656 Views
https://hackaday.io/projects/hacker/269449

Started putting projects on hackaday.io. This is not to be confused with hackaday.com. The hackaday domanes are a confusing mess of illegible grey on black text, but the few readers might find it more useful. It feels like rcgroups has lost attention to the hackaday, eevblog, tested.com properties as the RC world has expanded from toys to industrial robots which control cameras, clean floors, deliver food, drive taxis, & train athletes. An RC vehicle is just as often found delivering food now as it was doing flat spins, 10 years ago.



Steering the lunchbox continues to be a brutal occupation. The stiction algorithm as implemented did nothing. It started becoming obvious that control feedback behaves like an equation. No matter how convoluted the feedback algorithm is, the result converges on the same answer in the long term, like an equation which always outputs a sine wave despite having 1 added & subtracted to it many times. This is why control theorists write their feedback algorithms in equation form. It makes it easier to see what changes reduce to 0.

The stiction problem is specifically caused by the servo saver absorbing much of the motion & less because of the linkages. The servo saver absorbs much motion in left turns but virtually no motion in right turns. Maybe the integral has to be kicked based on swings in the PWM output instead of the heading error.
Posted by Jack Crossfire | Dec 09, 2017 @ 06:05 PM | 2,114 Views
93 miles of driving after the stiction fix, it could once again no longer go in a straight line. The next step would be sending more diagnostics to the GUI, in realtime. It may not be seeing the deviation in heading required for it to kick the integral or it may be waiting for a deviation in the wrong direction. After drifting right for a while, it suddenly kicks left. Showing the realtime deviation in heading, what deviation it's waiting for, & the feedback is part of the solution.


Other ideas were adding noise to the feedback, because it seems to knock itself straight when it hits bumps.


The raspberry pi zero W was too good to be true. After integrating 10 of them without any issues, packed one in a static bag & commuted with it. It no longer detected wlan0.

dmesg|grep brcm went from showing

[ 35.073582] brcmfmac: F1 signature read @0x18000000=0x1541a9a6
[ 35.103366] usbcore: registered new interface driver brcmfmac
[ 35.519555] brcmfmac: Firmware version = wl0: Aug 7 2017 00:46:29 version 78
[ 35.520794] brcmfmac: brcmf_c_preinit_dcmds: CLM version = API: 12.2 Data: 7
[ 42.937355] brcmfmac: power management disabled

to

[ 35.693070] brcmfmac: F1 signature read @0x18000000=0x41e041e
[ 35.693567] brcmfmac: brcmf_chip_recognition: SB chip is not supported
[ 35.693580] brcmfmac: brcmf_sdio_probe_attach: brcmf_chip_attach failed!
[ 35.693592]...Continue Reading