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About jfrouleau

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  1. @OffsetIsMyName : I successfully replicated the bug you described. I confirm that there really is a force that come out of nowhere. Here is an example craft : https://kerbalx.com/jfrouleau/The-Magic-Rotor .
  2. I didn't try to spin the propeller in the wrong direction but my rotor had a very similar configuration as yours. My angle of attack was not zero because I wanted to produce lift so it was between 2 and 4 degrees. Under heavy load the blades pointed upward to 30 degrees. It produced way more lift than it should have and once airborne the thing was unstoppable even if I reduced the throttle. It exploded 2 or 3 seconds later. Thats all I know, I did not investigated further but it's certainly interesting if you can put 0 angle of attack and produce great lift. Further tests would be needed before we can RELEASE THE KRAKEN !!! :-) (I love to say that). I also tried at some point to make a Flettner rotor making a rotating cylinder out of control surfaces. The thing didn't work as expected. It turns out the lift vectors were completely in the wrong direction for an unknown reason. In this case the control surfaces were pointed parallel to the rotation axis, so 90 degrees instead of 30.
  3. @OffsetIsMyName : I once experienced too some weird propeller behavior that may related to what you described (or not). I was trying to build a really heavy lifter heli with 2 contra-rotating rotors. The blades were made with WINGS just like you. I tried a version with fixed blades and it lifted about 250t. Then I tried another version with flexing blades attached to klaws and this is when something unexplained happened. Using the same wings and the same angle of attack the thing could lift... Idk I was at 529t and it lifted without effort and was even accelerating upward before the force was too strong it it kaboomed. So I don't know how much this could have lifted if it wasn't exploding from too much vertical acceleration. The mysterious force manifested itself when the blades were lifted vertically at their maximum angle of about 30 degrees. This is what happens when you have 500t + holding on 8 blades. Perhaps there is a bug to be exploited here Unfortunately I deleted the craft because it was a failure.
  4. @OffsetIsMyName This is fantastic ! I didn't know that. I imagine by combining this with the klaw bug I found which allow it to flex more than 30 degrees (see an example here https://kerbalx.com/jfrouleau/Experimental-Spinning-Klaw-Copter) we could make an interesting F-35.
  5. jfrouleau

    Hue-H7 Lynx

    @luizopiloto I'm trying to make a new rotor with flapping blades but it always wobble and I can't figure out why. Do you have any tip to help balance the rotor ? I examined your helicopter and they are very stable. I wonder what the magic trick is. Never mind, I was stupid I just found the cause. The bearing hole was too large
  6. jfrouleau

    Hue-H7 Lynx

    Hi, I'm the creator of the original flapping blades demo. I indeed removed this demo from KerbalX since we can now find other examples of this tech thanks to Luizopiloto. However, I did not really adopted this technique after that because of the rolling force Azimech speak of. I found it a better design to keep the fixed blades but counter the pitch force with strong elevators on the tail which are far from the CoM and thus have a good mechanical advantage like a long lever. You are right about the maneuverability allowed by the fact that the craft is not tied to the rotor which is usually large and have a good amount of kinetic energy and is difficult to change its rotation axis much like a big gyroscope. There is one thing I had in mind is to use 2 articulated rotors spinning in opposite directions to cancel the rolling force. I tried a version with contra-rotating (same shaft) but then the rotor discs tilt in opposite directions and collide with each other. So the other option is to make them on separate shaft (counter-rotating) and... this is where I left my experimentation with this. Theorically this would make a helicopter with almost no pitch or roll force caused by dissymetry of lift but it is yet to be made. Maybe my next build ? Keep the creativity going guys :-) Oh it looks like this guy has done it ! Counter-rotating articulated rotors.
  7. @EpicSpaceTroll139 I posted something for you on KerbalX that might interest you. Flexible joint with fuel crossfeed https://kerbalx.com/jfrouleau/LV-T30-Gimbal-Test
  8. @EpicSpaceTroll139 I retested the flexible shaft this morning and it looks like you're right. The thing was already flexing the same way before I changed the staging. I probably just forgot to free one klaw the first time I tested it like an idiot. Still it bends to about 60 degrees for 2 klaws which is what I expect it to do before problems occur. For 90 degrees you would need 3 klaws like my synchropter use on each side. I verified for the fuel crossfeed and indeed the klaw doesn't have fuel crossfeed which makes me sad So yeah... back to the first idea unless you also put the fuel tank on that last part of the articulation with the engine. Sorry I couldn't help more.
  9. @EpicSpaceTroll139 I checked your craft on KerbalX because I have experience with klaws and it looks like its something I can help with. What I found is that only 1 of the 2 klaws actually flex (not always the same one) which is I think the source of the friction. Here I just changed the staging and that solved the problem. Both klaws are flexing and the rotation speed stays the same no matter the angle (till you reach the klaw max angle). When assembling a craft with klaws, the docking sequence is important and have an impact on the structure of the resulting craft. This is why I usually decouple and dock each component separately (multiple staging) to guarantee the docking sequence. My method is the following: I start with the outermost component and make my way to the center so that you don't dock a component which is "sandwiched" between 2 parts. In this case you start with the component at the left of the leftmost klaw (see picture). Then you dock the component with the leftmost klaw, then the one with the rightmost klaw, and so on... Also for what I know the klaw has a maximum flex angle of about 30 degrees on each side which gives a total amplitude of 60 degrees. Reading my notes, it looks like you even can dock a craft with itself using a klaw. I made this test once. This is quite surprising knowing that KSP represent crafts with a tree structure. I also found that using a rotating joint with klaw seems to limit the rotation speed like if the klaw had a maximum flex speed which limit the rotor performance. You could probably improve the performance by moving the turbine wheel / blower after the klaw joint so that the klaw just flex and don't rotate. The turbine wheel would rotate on the same axis as the propeller. Btw this is a very good idea you had ! I'm looking forward to see a craft using this mechanism of tilt rotor. I wish it works. Maybe a similar technique could be used to make a thrust vectoring wheesley actuated by ailerons or a 30 degrees gimbaled LV-T30 for a lower tech / lower cost space shuttle.
  10. Hi guys, I tried my helicopters in KSP 1.4 and they are broken too. They all break EXCEPT the KG-3 Barracuda which seems as reliable as it was. I couldn't say why but maybe we can find some elements of answer here. If I had to guess I'd say using heavy parts for the bearing is the lucky charm.
  11. May I have my name changed to jfrouleau
  12. jfrouleau

    Kerbal Spice Program

    I call it the flying hot-dog...
  13. jfrouleau

    Pulse Detonation Engine

    Hi, I was able to make this engine work again in KSP 0.90 with the following cfg and the latest Firespitter dll. I also added a variable speed to the rotor following the throttle and it should work in career mode. I kept the values of the original cfg. Enjoy ! PART { // --- General Parameters --- name = SM-Pulse-Detonation Engine module = Part author = SasquatchMarmalade // --- Asset Parameters --- mesh = model.mu // --- Node Definitions --- //node_stack_top = 0.0, 0.3820, 0.0, 0.0, 1.0, 0.0 node_attach = -0.6386, 0.0, 0.0, -1.0, 0.0, 0.0 // --- FX definitions --- fx_exhaustFlame_blue_small = 0.0, -10.3, 0.0, 0.0, 1.0, 0.0, running fx_smokeTrail_light = 0.0, -10.3, 0.0, 0.0, 1.0, 0.0, running fx_exhaustLight_blue = 0.0, -10.3, 0.0, 0.0, 1.0, 0.0, running fx_exhaustSparks_flameout = 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, flameout // --- Editor Parameters TechRequired = aerodynamicSystems entryCost = 4000 cost = 5000 category = Engine subcategory = 0 title = SM-Pulse-Detonation-Engine manufacturer = SM Aeronautics description = The basic operation of the PDE is similar to that of the pulse jet engine; however, the PDE uses detonation waves to combust the fuel and oxidizer mixture. This PDE includes the housing and intakes. // attachment rules: stack, srfAttach, allowStack, allowSrfAttach, allowCollision attachRules = 0,1,0,1,0 // --- Standard Part Parameters --- mass = 1.8 dragModelType = default maximum_drag = 0.1 minimum_drag = 0.1 angularDrag = 2 crashTolerance = 5 breakingForce = 200 breakingTorque = 200 maxTemp = 4000 MODULE { name = ModuleEngines thrustVectorTransformName = thrustTransform exhaustDamage = true ignitionThreshold = 0.01 minThrust = 0 maxThrust = 400 heatProduction = 1000 useEngineResponseTime = True engineAccelerationSpeed = 2 engineDecelerationSpeed = 2 fxOffset = 0, 0, 0 PROPELLANT { name = IntakeAir ratio = 10 } PROPELLANT { name = LiquidFuel ratio = 1 DrawGauge = True } atmosphereCurve { key = 0 3500 key = 1 3500 } } MODULE { name = ModuleAnimateHeat ThermalAnim = EmissiveAnim } MODULE { name = ModuleResourceIntake resourceName = IntakeAir checkForOxygen = true area = 0.04 intakeSpeed = 1000 intakeTransformName = Intake } RESOURCE { name = IntakeAir amount = 0.5 maxAmount = 0.5 } MODULE { name = ModuleAlternator RESOURCE { name = ElectricCharge rate = 1 } } MODULE { name = FXModuleAnimateThrottle animationName = DetLight dependOnEngineState = True //responseSpeed = 0.1 } // --- Firespitter Modules --- MODULE { name = FSengineSounds // The engine start sound engage = sound_vent_medium // The constant thrust independent background hum of an engine running = SM-PulseDetonationEngine/Sounds/sound_PDE // The thrust based pitched main engine sound power = SM-PulseDetonationEngine/Sounds/sound_PDE // The engine shutdown sound disengage = sound_vent_soft // Loss of fuel flameout sound. If you don’t have a separate sound, consider using the same as disengage. flameout = sound_explosion_low // The default pitch of the engine power sound. 1 is the same pitch as the original sound file. powerPitchBase = 1.0 // How much above the default pitch the power goes based on thrust. final pitch = powerPitchBase + (thrust * thrustAddedToPitch ) thrustAddedToPitch = 1.0 // How quickly the engine power sound volume ramps up from silent when started. set to 1 for immediate full volume. This value is added to the volume every 0.2 seconds until it reaches 1. powerFadeInSpeed = 0.005 // How long the volume is off after starting the engine, to allow the engage sound to be heard powerFadeInDelay = 0.5 // Thrust values below this level will yield a silent engine sound. 0.1 means 10% throttle is the cutoff. A 0.0 always keeps the sound on while the engine is running. powerLowerThreshold = 0.0 // Volume adjustment for the different sounds listed above runningVolume = 1.0 powerVolume = 1.0 engageVolume = 1.0 disengageVolume = 1.0 flameoutVolume = 1.0 warningVolume = 1.0 } MODULE { name = FSplanePropellerSpinner // The gameObject to Spin around its forwards axis. Can be a parent to other sub objects. propellerName = Nose // The propeller rotation speed in RPMs when the engine is ignited, independent of throttle. Positive or negative values can be used. Use 0 for a wholly throttle controlled rotation. rotationSpeed = -15 // The propeller rotation speed in RPMS that are added to the rotationSpeed according to the final thrust of the engine. i.e., higher throttle makes spinny thing go fast. thrustRPM = -240 } }
  14. Hi, I was building a rocket yesterday and wondered how to design a vessel with optimal staging. While having each stage delta-v is very useful, I never know when it's better to raise delta-v by using a bigger stage (tank + engine) or to add another stage. I think the optimal way may be to have the biggest delta-v with the less possible mass because we know that the more mass you have on your upper stages, the bigger the lower stages have to be to lift them off. So I have a suggestion for this mod if it's possible to implement it : having a delta-v to mass ratio displayed for each stage. The bigger the number, the more efficient the stage is for its weight in its current staging configuration. What do you guys think ? Would it be useful ? Or maybe there is a better way to do this.