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FleshJeb

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Everything posted by FleshJeb

  1. On a scale of 1-10, I rate this "Mmmm Bork Bork Bork!" (Alternate rating: "Beaker sings Yellow")
  2. I can put forth better ideas any time I like: https://usnc.com/ultra-safe-nuclear-technologies-delivers-advanced-nuclear-thermal-propulsion-design-to-nasa/ referenced here: https://en.wikipedia.org/wiki/Propellant_depot#History_and_plans It's not like I called Starship a garbage scow, it's just got some glaringly obvious issues as a moon lander. (I also happen to think methalox is a bit of a dead-end technology beyond LEO.)
  3. I knew a "bear" that carried an M-14 in Vietnam. (Dave was a Marine and a giant nerd. He would have loved KSP if he hadn't passed on before the release.) Before we all get sent to moderator-hell, here is the latest ISS news. Spacewalk set for Nov 30: https://blogs.nasa.gov/spacestation/2021/11/23/spacewalk-preps-during-human-research-robotics-and-physics-today/
  4. I'd argue that for NASA, having a robust and well-tested orbital refueling system is a more important development than going to the moon. That's the key to the rest of the solar system. If I were them, I'd get that done, cancel the Starship lander, and re-open bidding for a more fit-for-purpose moon lander.
  5. Relax, you goobers. If they thought it were critical, they'd be delaying it by more than 4 days. They're probably going to run it through the same checklist that they did when they pulled it off the boat. It's like watching a kid fall off a bike: You look them over to make sure they're not leaking fluid and you put them back on the bike.
  6. I was being somewhat facetious. In an interpersonal conflict, the right solution is to just cut those people out of your life. I've attempted to edit the following to skip the politics, and be more about the game theory aspect: This was a ratcheting escalation that skipped too many teeth on the ratchet. If a satellite had been destroyed that was in a more reasonable orbit, very few people would have a problem with it. It also would have inferred that the capability for a more destructive action is there, and proved the point. Actually carrying out that more destructive action was both cause for condemnation AND a strategic mistake. It invites (justifies?) what I'll loosely call a "FAFO Response"--That's what happens when you're playing a game and egregiously violate the rules.
  7. People who argue like Stefanovich don't get punched in the face enough.
  8. @SOXBLOXIt's not fair to nerd-snipe me with physical geography. (It doesn't help that my favorite place in the world is in a high desert filled with escarpments and volcanoes.)
  9. The only conclusion I can draw is that human beings are ridiculous.
  10. Gravitational anomalies: What GPS equipment reports is latitude, longitude, and a height above a reference ellipsoid. To turn an ellipsoid height into a useful height, you compare it to the Geoid, which is a height map of the gravitational anomalies relative to the reference ellipsoid. It's basically a big database of values keyed to lat/long. "All points on a geoid surface have the same geopotential (the sum of gravitational potential energy and centrifugal potential energy). The force of gravity acts everywhere perpendicular to the geoid" 2 is the ellipsoid, 5 is the geoid: "the geoid's deviation from an ellipsoid ranges from +85 m (Iceland) to −106 m (southern India)" If you know your US geography, these geoid heights make sense: Here are some of the later steps in how GPS equipment shows a useful elevation (Orthometric Height): I'll think about that some more on a day when I haven't been building and measuring a network of very large triangles at a sewage treatment plant. Bonus: It's for deformation monitoring, so it's time-dependent. My brain (and the rest of me) hurts.
  11. For a given RPM, blade pitch determines your maximum speed. The torque of your trim flaps will be roughly proportional to your speed squared. So a good approximation is that trim flap angle is a function of your blade pitch. What I recommend for an easier build: Have enough torque to drive your blades at maximum RPM no matter what the pitch is. (Higher pitch requires more torque.) Then, instead of doing any math, figure out the parameters empirically. So, you would set up your blades on the H&N keys, and your trim flaps on your I&K keys. Get off the ground and get into level flight at a relatively low sustainable speed (low pitch). Play with your trim flaps until the SAS isn't working too hard to control the roll axis (Roll axis indicator in the middle). Write the pitch and trim numbers down. Repeat for a medium speed and a close to maximum speed. Set your KAL to your throttle, and manually plug the pitch and trim numbers on the timeline where you want them to be as a fraction of the throttle. You might have to use the curve setting to smooth it out and shift it around a bit after more testing. Single-props are always going to be a bit fussy, and the SAS will have to eat up some slop, but you can improve it greatly. You're going to want trim flaps (or any control surface) large enough that you don't have to deflect them more than 10 degrees, and preferably 5. They'll be much more draggy otherwise. If you have any more questions, feel free to ask. I'm a bit rusty, but I'll try to help.
  12. Sorry, I left the wrong impression due to my mental frame of reference. It’s not the moon doing that. I’m saying my best non-lab bench results have negligible drift over an 8+ hour day. Any drift I get is from differential heating as the sun moves. Comparison of forces involved: https://www.quora.com/How-does-the-Moons-gravity-affect-humans Hmm, check my math, I’m on my phone: arctan(0.0034/981) =0.000199 degrees. The best I can measure is 1/3600 degrees = 0.000278. Theoretically, if the moon moved 180 degrees relative to your position, you’d double the 0.000199, so I might be able to detect it with a bench test…provided I didn’t breathe, the building foundation was thermally isolated, and no mosquitoes farted. @kerbiloid You ninja’d me and we agree! Thats actually a significant amount. I wonder how astronomers maintain sub-arcsecond pointing? Gyros? Reference stars?
  13. I think it's more of a force vector problem. Take the force of gravity on an object on the surface of the Earth, and then the force of gravity imposed on that object by the Moon set at 90 degrees to the Earth vector. Then it's just arctan(F_m/F_e). Speaking as a surveyor, I can set an instrument up on a tripod, on dirt, in the sun, and expect it to hold about 5 arcseconds in the vertical all day. (The moon will have moved several degrees during this time.) This is presuming I've let everything heat up to thermal equilibrium first, and then leveled it. In practice, I usually see a 20 arcsecond drift because I don't have time for that, and it's got an internal compensator to apply corrections to to my angular measurements. In the worst-case scenarios, on a surface with a lot of thermal expansion (like asphalt), it can get to 2-3 arcminutes. Even then, the compensator can correct that if I'm doing lower-accuracy work.
  14. I appreciate that you often provide good food for thought and interesting sources. --- Carbon removal DOES seem to be being promoted as a panacea in order to delay making hard choices, and the article presents a solid critique. (This supports your criticism of Climate Remediation earlier in the thread.) My personal opinion is that it's not something we should rely on, but look at as a bonus should it ever become technologically and economically viable. Extra credit to make up for some of the inevitable policy failures we'll encounter. --- Shellenberger on the other hand...I spent a couple hours reading his articles, and then some criticism of his work. He DOES have compelling and valuable critiques of the apparent zeitgeist around climate change. His arguments get a bit rough in tone. I've found that people who engage in "argument from snideness" are ideologues who often misrepresent things in order to sell their position. The same critique applies to the more extreme purveyors of climate alarmism. This is an excellent, critical review of Shellenberger's latest climate book, and Peter Gleick's CV on climate science is VERY impressive: https://yaleclimateconnections.org/2020/07/review-bad-science-and-bad-arguments-abound-in-apocalypse-never/ Another critical review that I don't think is as well-presented, but adds valuable additional insights is here: https://lareviewofbooks.org/article/the-stories-michael-shellenberger-tells/ Ultimately, Shellenberger's entire career has been in Public Relations, not science, and even his own former co-author and fellow founder of the Breakthrough Institute, Ted Nordhaus has distanced himself from him. (Breakthrough has some decent, nuanced articles, BTW.)
  15. The alternative was to post something about Mark 48 ADCAPs and debris fields at the bottom of the Atlantic, but this is much more productive.
  16. Maybe 0.3 cm, per this (which also has other useful information):
  17. http://toughsf.blogspot.com/2017/02/how-to-live-on-other-planets-jupiter.html?m=1
  18. Currently 2/3 of the way through Garrison Keillor's collection of short stories, "The Book of Guys". The protagonists are all a bunch of miserable jerks, but I think any man who's lived a little will recognize parts of himself (or his past selves) in them. The stories are written in the style of what Ursula Le Guin calls "psychomyth", so they're quite surreal. If you like Vonnegut, you'll like this. I don't know if anyone under 40 can fully appreciate it, but I'm enjoying it. "Enjoying" is the wrong word--More like facepalming, wondering how I lived through it all, and appreciating the fact that I know better now.
  19. It's a vacuum chamber--Drain most of it, and the rest will boil when the chamber gets pumped down again. I had the halfway stupid-idea that maybe they don't. The whole assembly might be robust enough to just take the beating. The mass of the projectile is pretty miniscule compared to the whole rotor. I screen-capped a few images from renders of the design. (Which they list as 450 RPM = 47 rad/s) https://www.spinlaunch.com/orbital I did some research, and those types of bearings are typically instrumented, so they can keep an eye on the health and replace it before a critical failure. As it happens:
  20. At the time I created this account, I was leaning on MechJeb a lot to teach me how to play. FleshJeb is the meatbag who tells MechJeb what to do. (Also, It's vaguely dirty and hopefully unsettling.) I use a different username on every platform and try not to cross-identify myself. (Although a few people around here know my usernames on YouTube and Discord.) My PFP is a pixel-perfect copy of the default forum avatar, because I like being contrary.
  21. I'll step in for a second and say that I LIKE Kerbiloid, I just think he's wrong (and I can prove it). English isn't his first language and it's a heated discussion--Of course it's going to get messy. I've made quite a few editing mistakes in this thread that I only noticed after the fact. My perspective is that I'm LUCKY to be able to argue with someone who has made the effort to learn MY language. EDIT: Per Joe ninja'ing me, I'll do my refutation when I get done with work.
  22. Is it these? https://bugs.kerbalspaceprogram.com/issues/5250 "When the ore tanks are full and your craft is drilling and converting (via ISRU) at the same time, the drilling proceeds at the maximum rate, even though the utilization of ore may be slower than the extraction of ore. The excess ore is not stored and is simply wasted. This can become a big problem when mining asteroids due to their finite ore. This issue is independent of time warp." https://bugs.kerbalspaceprogram.com/issues/10125 Partially related to Bug #5250 - the fix left some related issues unaddressed When ore containers are filled, the actual ore depletion of the asteroid now matches the amount of ore actually being stored (and then processed), however the asteroid drill continues to report 100% (or whatever limited by other factors) load, which also gives full heat production and power consumption way beyound the actual work done by the drill. Even if the drill is actuallly producing nothing, when the storage is full and the converters are off. In comparison, surface drill reports actual load (and has its power consumption and heat production scaled to it) limited by the ability to store the ore in such situations with full ore tanks, that is being limited by ore conversion rate if ISRU converters are active and completely stopping if no ore is consumed. I'm big into conservation of mass/momentum in my physics sims. This is one of the many reasons I answer the KSP2 surveys as "Will not buy." I think I mentioned it to you privately, but I'm so done with dealing with poor performance and bugs that I haven't opened KSP since April.
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