Pds314

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  1. The goal of this challenge is to, starting at KSC, get as far north as possible with a stock AFK rover. Rules: 1. You may not control your rover once you exit the green square. Within the green square you may control it as normal. 2. Must be Kerbal'd. 3. Any propulsion method is allowed. 4. It is permitted that your rover crosses water to get to its destination. 5. The KAL-9000 is allowed. If you want to preprogram some crazy sequence of maneuvers into it, you can. 6. Remember, the challenge is farthest north. Not farthest distance traveled. 7. No hax. Stock rover. Stock physics. DLCs are allowed. 8. At least one Kerbal must be on rover at destination. 9. No prolonged ballistic or aerodynamic flight. By which I mean it shouldn't fly like a plane or rocket to its destination and then land there. Scoring: The score is measured by the latitude North.
  2. The Deep Space Kraken did this. No. Not a different crazy bug. The Far Lands was caused by the Kraken. It is the same bug in a different environment. The same thing can both eat your ship and turn your Minecraft terrain to swiss cheese.
  3. The original Kraken is well understood and doesn't just inhabit KSP but also other games such as Minecraft. It is known by many names but has different effects on different games. (In Minecraft, it created the Farlands and herobr- oh wait no he didn't exist.) Specifically, it has to do with floating point accuracy in physics computations. The way KSP stores physics information about a vessel is as 32-bit floating point numbers. Basically a binary version of scientific notation. One obvious problem we can see here is that when the exponent gets really large (i.e. the physical quantity being measured is a very big number), the precision degrades a lot and becomes more quantized. So if you're, say, 1000 km from whatever origin the position is based on, part positions can only be accurate to within about a meter. Well, if you have part positions with an error of a meter, they are gonna clip into each other and generate crazy phantom forces. Unfortunately, KSP is a game where the whole point is to explore space. This means that whatever fixed origin you could possibly choose would likely not just be 1000 km from the places you want to go but tens of millions of kilometers. The solution is that the game's physics NEVER deal in distances of thousands of kilometers. The origin of all physics calculations is the ship in question. However, the floating point Kraken manifested itself in other ways. It is not just position that is stored in floating point but velocity. At surprisingly reachable speeds, this could manifest as phantom force, torque, or other effects. The solution was to cap the velocity relative to the sphere or influence in question at 750 m/s, then operate in a different frame of reference above that speed. This is called the Krakensbane. It was supposed to kill the Kraken. Or at least contain it. Instead, it allowed us to unleash it. Landing leg physics was and is strange. First, it let us slowly ascend, hovering and gliding in a bizarre, mass-independent way (Kraken drives with more deadweight payload mass were actually typically better accelerating). These devices really came into their own above 750 m/s though. However, crossing this speed barrier with the landing legs extended would typically cause the device to explode, destroying the craft and often stopping whatever was leftdown to 1 m/s or so. At low speeds, the device could act almost like a wing or rotor. It could generate phantom lift and drag and could be flown around like a helicopter, but could not exceed about 150 m/s, even outside an atmosphere, without a high chance of self-destruction and excessive phantom drag. The device's behavior changed above 750 m/s. The craft would shake and accelerate at roughly 10-40 G in the direction the device was pointed until a landing gear broke and it spun out of control or until it was turned off. There are still functional devices but they now work by altitude instead of speed and enter a low speed mode gracefully when within roughly 150-300 meters of the ground. (Also the altitude where adjustible landing gear mod begins to stutter severely). As time went on, more floating point issues were fixed, including those in the transition between spheres of influence. And ultimately the original Kraken is pretty rare to nonexistent these days in KSP with the exception of common purely graphical bug that looks like macroscopic Z-fighting and mesh glitches, but new Krakens have been named based on other bugs that either destroy craft, cause phantom forces, or allow for reactionless drives.
  4. NEVER make a fairing the root part. I have found that doing so with a boat removes the fairing's buoyancy. Which is ashame because it means the only way to autostrut it is to make it the heaviest part. If I had to guess I would say root part fairings are similar to nonexistent fairings.
  5. We can easily get 15 km/s what do you mean? Ion drives have 40 km/s exhaust velocity. Just bolt an ion drive to some fuel tanks and RTGs, 4x timewarp, and let it burn boatloads of fuel overnight. 100 km/s is well within possibility. And even without ion drives, my high speed mission to Duna used a pretty crazy amount of Delta-V. 3500 for launch. 7500 for NTR transfer, something like 1500 for Duna ascent. And about 6000 to return to Kerbin. That's at least 17000 Delta-V without even considering the possible extra fuel with no lander.
  6. Or trying to land with a craft with marginal TWR. Or in a BDA dogfight, or reentering (in fire).
  7. Yes I'm aware, but the community maps don't use escape velocity or vis viva or anything else to compute them. Just learned experience by hopefully sane designs. Indeed, the most commonly used map says 3400 to LKO and 930 to Kerbin Escape. This totals 4330 Delta-V to Kerbin Escape. The actual escape velocity is 3431 m/s. And you are already at 174 m/s so the minimum delta-V a perfectly aerodynamic cannonball could need to escape Kerbin is actually 3257 m/s. The map overprovisions by 1070 m/s! This is to very crudely estimate turning, gravity, and aerodynamic losses. But these numbers are very beatable by high-TWR aerodynamically optimized designs. And likewise far too conservative for ungainly designs. Laythe is smaller than Tylo with equal surface gravity. Yet requires a nominal 3790 m/s to escape from by the community map. Compared with 3320 for Tylo. This is despite its escape velocity from the surface actually being 2801 m/s to Tylo's 3063. A 262 m/s difference.
  8. The community maps are not an exact science. Take Tylo: escape velocity is listed by the wiki at 3068 m/s. So in theory, a cannonball launched at that speed from the ground should reach Tylo escape. However, the recommended delta-V for Tylo ascent and escape is 2270+1050= 3320. So 250 m/s. Delta-v is assumed necessary for gravity and turning losses. Laythe, meanwhile, recommends a whopping 1000 or so Delta-V over the escape velocity. Depending on craft design, mission profile, and pilotting, you may need significantly more or less delta-V than the chart says.
  9. Real life year (365.24*24 hours) or Kerbin year (426*6 hours)?
  10. With the compact miraculously-efficient propellers and especially electric ducted fans in Breaking Ground, can an electric-ion plane reach orbit in a single stage from the runway? The goal of this challenge is to get a single-stage electric-ion vehicle from the runway to as high a speed, altitude, and if possible, Periapsis as possible. Should orbit be achieved, the goal will be to achieve orbit with the best remaining capability to reach further destinations.
  11. I just thought of something incredibly silly but kinda realistic. A pilot seat with a turret mounted to it with a 150 rpm 45 ACP gun that overheats after only 6 shots. Muzzle velocity of 300 m/s.
  12. Yeah we need lighter, smaller engines and weaker guns, and a mandatory open cockpit rule, but I'm definitely down for that. I'm thinking short rotary and inline engines in the 100-250 kg range, with minimum aircraft weights for fighters being 400 kg or so and heavy fighters being 850 kg. Static thrust should be around 3-8 kN but should drop off a lot with speed due to fixed pitch props. Basically you should be getting next to no thrust at 80 m/s and very low thrust well before that. With the option for single engine heavies being available as well. Does anyone know if any caliber besides 7.92 or .303 or similar was used in WWI?
  13. Just no discards. You can use stage or any other action groups or methods to order the burns, just don't lose parts.