That's a nice piece of motor engineering. It's well known that high ratio gearboxes for robots are a headache. Back driveability doesn't work, and tiny teeth are fragile. Comments on this go all the way back to Feynman writing about his time spent engineering automatic gunnery aiming systems in WWII. This new discovery is that gearbox problems mess up a machine learning system. It's trying to track gearbox noise and is using up all its learning capacity on that. This discovery means that robotics people can tap machine learning funding for motor and gearbox development. Robotics labs used to be really low-budget operations. No longer. What you really want is a direct drive motor, but those have to be large-diameter. They can be flat; that's a pancake motor. That's too large for fingers. So their compromise moves partly in that direction; the rotor is flatter, torques are higher, speeds are slower, and gearbox ratios are lower. As they point out, reflected inertia is the square of the gear ratio, because the gear ratio gets you both going out and coming back. So this is a bigger than linear win. Good back-drivabiilty means much less risk of gear breakage on overload. Some of the academic designs, such as harmonic drives and series elastic actuators, have huge gear ratios in a small space. That's OK for prototypes but not production. As I've mentioned before, "you cannot strip the teeth of a magnetic field", a line from a GE electric locomotive salesman around 1900. If an overload forces a motor backwards, nothing breaks. Would have been nice to hear more about the motor design. That's the real achievement here. There are CAD tools which understand electromagnetic fields now, so strange motor geometries are not as much of a trial and error and experience process as it once was. It's also respectable for an EE to work on rotating machinery again. That field matured around the 1960s, and until computers took over motor control, didn't change much.
This is manifestly false. My wife grew up in Shanghai, and you'll have to go quite some distance to find someone more critical of the PRC and CCP than she is. And it's with good reason. She grew up during the cultural revolution, and was largely raised by her grandmother because literally every other person in her extended family was in prison or work camp, not because of anything they had actually done wrong, but for political reasons because the whole family was blacklisted. And that's not just the old days. Her father died as a direct result of Chinese Covid policy. During the pandemic her cousins still in the country would ask her (on Skype) "is X true?", and largely their perception of what was going on was false. She would exfiltrate encrypted news reports to them - until those started getting blocked. Her dad's estate still has affairs that need to be resolved, but we've decided not to return to China until Xi is gone, as it's just not safe. It doesn't get much airplay, but there are currently a couple of hundred Americans who are being illegally detained in China right now. It's not worth the risk. My first trip to China was about 30 years ago, shortly after we got married. And back then, I would have said that you were right. Honestly, it felt like for the average person in their day-to-day-lives, the Chinese were less under the governmental thumb than we are. People from the countryside would bring their produce into the city to sell, or cook dumplings and buns to sell on the side of the street - stuff that in America we'd have to get permits for. It seemed that the oligarchy had an understanding with the people: let us control the big picture, and we'll look the other way for the little things. But Chinese politics is a pendulum swinging very widely. From Tienanmen Square and Tank Man, it had swung quite a bit the other way. But today, it's come back 180-degrees. Xi is really trying for a Cultural Revolution 2.0. These impressions largely match what I hear from other Chinese immigrants - except for Party members, who tend not to want to talk about it at all. I'm afraid that you've been listening to too much propaganda.
WWII didn’t start overnight. The Sturmabteilung (SA), also known as “The Brownshirts,” have a strong similarity to what we’re seeing with ICE and CBP. The SA were Hitler’s enforcers before the SS, during the 1920s and early 1930s. They were eventually usurped by the SS during “Night of the Long Knives” where SA leadership were executed by the SS. Largely because Hitler had felt threatened by the power Ernst Röhm had amassed (among other reasons). And the SA, like ICE, was made up largely of untrained sycophants and thugs who enjoy violence. They committed violence, harassed citizens, and had no consequences for doing so. They were also instrumental in laying the foundation for the genocide and atrocities committed by the Nazi party. It’s not a dishonor to their memories, or the atrocities committed, to call that out. It is not a dishonor to say there are stark and real similarities between the way the US is operating and treating civilians. I personally find the opposite, IMHO it is dishonors their memories to refuse to acknowledge the similarities. I’ve posted a comment similar to this one here before, and like how I ended it. I strongly encourage you to read about the history of Nazi Germany and how it came to happen. It wasn’t just a zero to death camps, it was 15 years in the making. That history is deeply shocking, as it is depressing, because the parallels and timelines are too similar for anything besides outright discomfort, sadness, and fear between it and the US. But without knowing it, we are ever more likely to repeat it. One final thing to note: the US has a history of extreme violence, slave patrols and the treatment of non-whites of the 19th century were an inspiration for Hitler.
↙ time adjusted for second-chance
Tell HN: MitID, Denmark's digital ID, was down
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