dnbattley

I was not completely clear: they cannot survive, as is clear if you ascend a Kerbal on an EVA seat post a certain altitude (or else cheat them into another SOI) then they "pop". Plus you are expressly forbidden from removing the helmet in vacuum.

Interesting idea, but if they are holograms then they must have developed hard light technology (akin to Rimmer from Red Dwarf) since they do have an effect on Kerbal survivability in low pressure environments...

It launched like it had just had a space hopper put underneath it, you mean? I rest my case

Hate to contradict you on this comment my friend, but: Oh My Yes It Can!

We all know and love the Kerbal shape, with oversized head and bulbous helmet offering clipping challenges, or worse preventing access, to poorly placed EVA equipment like ladders. But it occurred to me today that the Kerbal helmet must, despite it's solid appearance, be inflatable. My reasoning is below: please tell me if you disagree. This also raises some interesting conclusions. * Reason 1: Helmets are removed and disappear. We all know helmets can be removed in Kerbin and Laythe atmospheres, and we see it disappear, but we don't question where it goes, nor how it can be pulled back out instantly. The inflation theory covers these by proposing that the helmet, once deflated, resembles little more than a sock and can be rolled up and put away. * Reason 2: junior airlocks are clearly too narrow to fit a rigid Kerbal helmet. We also know that they cannot remove their helmet in a vacuum. Yet a Kerbal can enter them. The only reasonable solution is that the helmet must be able to flex somehow as they enter the airlock and pressurise. * Reason 3: crash tolerance and bouncing. Dropping a Kerbal on their head is often survivable with an impressive bounce possible if dropped directly on their head. With an inflatable helmet this phenomenon is easily explained, where the pressure inside creates a protective balloon around the Kerbal's head. * Reason 4: floating. A Kerbal flies upwards from underwater at some speed. The buoyancy of the inflatable helmet provides an explanation of this. So the logic points towards helmets being inflatable, and not solid, but this raises some fascinating questions: 1 Is there an upper limit to Kerbal pressure tolerance? For the helmet to inflate and yet look solid, even on Eve, suggests that the helmet material is very tough and that extremely high air pressure exists inside. This raises interesting questions about the Kerbal physiologal ability to breathe at high pressure and also to withstand forces (which we were already aware was high from previous ground impact studies). 2 Does helmet clipping (e.g. around an EVA chair) matter? If the helmet is indeed able to compress, but the game is simply unequipped to visualise this, then should it be considered poor form? Provided the head itself is not clipped then the suggestion is that the helmet will "mould" to the available shape. 3 Thus the ability to place ladders on Eve landers that frustratingly prevent Kerbal ascent to the command module due to a minute overlap on helmet shape after a long and arduous journey with no quicksaves on route and not enough money in the bank to launch another mission should be considered a bug, and reported as such. ;) But what do you think? Does the inflatable helmet theory clear up a number of unanswered questions for you, or do you have a better suggestion. Please discuss below.

To be fair the challenger never explicitly forbade k-drives...

Hmmm, strange then. It was based on three LY-05 landing gears and an inflatable airlock...

I have found and squashed this bug: when thrusting in Kerbol SOI (particularly high SOI), the K-drive wheel breaks almost instantly. This doesn't happen in any planetary SOI (as far as my testing has determined). Therefore the solution is i) to make sure you are travelling from one planetary SOI to another wherever possible and/or ii) bring along an engineer...

August is over, but I have had the opportunity to return to KSP after something of a hiatus, and present my Tamed Kraken Spaceplane: veering away from true battery-less activity with some traditional SAS assistance (though I have some other ideas I'll be working on to advance that side of things), it takes the K-drive above to it's logical limit with a VERY easy and fun to fly spaceplane.

Very cool! I sometimes wonder how much "lostech" knowledge there is around the forum where contraptions have been discovered, explored, and then forgotten. It seems as if the design is fundamentally identical to the K-drives above, but as two separate crafts presumably timewarp was not possible, which would have limited its value beyond that of a curiosity.

Hmmm... You seem to have covered the same diagnostics I'd try, but one other thing is to try time warp after disabling SVI for both sides of the drive and see if that "snaps" anything back into position that has been pushed out. If course it may be that you have discovered a top end speed limit of the K-drive tech, after which the K bites back... If you share the save game I'd be happy to root around in there and see if I can see anything amiss in the vessel config, though that is potentially a long shot.

This may actually be possible, after a fashion, by using EVA seats and an automated "scraping" mechanism... I'll give it a try next time I'm near my computer.

I've never tried it, but there is a section of the save file where mods are listed as "true/false": might it be possible to disable active mods such as life support via that?

@Flying dutchman in case you weren't already aware, there is a way of generating exact symmetry for arbitrary rotational symmetry >8: It is particularly useful for creating gearing, but does have a tendency to invoke the kraken if you go too far (e.g. I have a series of 8, 16, 32, and 64 gear subassemblies, but 96 or 128-symmetry immediately and spectacularly kraken on launch, though this may just be that my radius/n - which I made constant to allow the gears to all mesh - ratio needs to be larger). Impressive. With a flywheel it might be able to maintain that speed, but the key will be to understand its ability to maintain RPM under load: I've struggled to maintain airspeed with my designs (admittedly based off a narrow-band scanner, rather than pistons) and stall shortly after take off.

Welcome to the movement! I am away from my computer to take a look at this at the moment, but is the piston not controlling the acceleration? If so then I'm afraid the battery in the probe core is critical in driving that, with the RTGs recharging that. You have mastered the fundamental design of the Kraken Drive, however, and so I look forward to seeing where you take it next!

One further postscript: on a whim I just tried to see if engine vectoring could be used to generate K-power, and in short it does, but only on a few engine types (most notably the vector)! I will definitely be investigating this further...

I shan't bother posting photos, but tonight I was able to take the Magic Carpet Mk4 (which makes primarily cosmetic improvements to Mk3, but also adjusts the KAL control system slightly and moves the command chair to below the main fuselage to more easily avoid crisping up Jeb under acceleration) on a longer mission to Eve - which, with the unlimited delta-V available, allowed me to arrive into stable Eve orbit a mere 9 days after launch. While atmospheric heating was a non issue (I could easily zero out velocity just before hitting the atmosphere), an ambitious sea landing under K-Power alone proved to be too much to ask (I will have to add a parachute!) and resulted in one of the drives becoming damaged (which, in turn, created a torque on thrust which made the vessel uncontrollable). However, the mission did successfully test the K-Drive through extended timewarps (across multiple SOIs, and including the descent into Eve during which I successfully tested its manoeuvring capability at x4 physical timewarp) with no ill-effects. I was unable to attempt an Eve take off on this version due to the damage on landing, but that will be the next milestone, after which it should definitively be capable of infinite travel anywhere within the Kerbol system... ...well ok, one photo, just for lols:

My current obsession with K-drive technology continues to yield reportable outcomes: the Magic Carpet, now on it's 3rd iteration, was taken for its inaugural spin this evening, and the mission was a complete success with all phases: launch -> orbit -> Kerbin escape -> retrograde orbit -> targeted approach -> safe landing, all completing successfully in a single take. The key innovation in the Magic Carpet range has been achieving true yaw/pitch control using only Kraken drive™ technology, rendering reaction wheels practically unnecessary and thus achieving true "battery-less" flight. The main thrust continues to develop unbelievable thrust (max recorded acceleration was 29G on this occasion), and while there are some potential improvements I can still make to its rather twitchy handling the upper atmosphere, I am coming close to a point where this project might be considered "complete" - at least until I regain the ability to record videos of the Magic Carpet in action (hopefully sometime later this month). Full mission report here: https://imgur.com/a/RBuzIsx Craft file: https://kerbalx.com/dnbattley/Magic-Carpet-Mk3

I am pleased to present what may be my most bizarre - and possibly greatest - battery-less creation so far: The Magic Carpet Mk1 Controlled, as you can see, via landing wheels and elevons, it is capable (in theory, at least) of both low level flight and interplanetary travel. I wont pretend it doesn't require some effort (due, in part, to limitations inherent in the axis controls), but with rudimentary pitch and yaw control, as well as vertical and horizontal translation, it is possible to fly with some moderate control even without any reaction wheels.

Wow thanks! I feel honoured to be associated with such esteemed company.

Et voilá - I present the Kraken Drive Mk 3 Lite The Infini-K-Drive of the Kraken Drive Mk3 Lite enables take off and landing on Kerbin without any electrical power. The normal ascent profile is to point straight upwards, with full throttle providing a gentle ascent to about 250m, then very rapid acceleration (throttling back is essential to avoid self-incineration) up to 20k, then coasting above the atmosphere, before heading where required (achieving orbit is not necessary). Here, the craft was cheated to Tylo orbit, and landed, to quickly test its performance landing without an atmosphere. Slowing down from orbital speeds is easy, but final touchdown is somewhat fiddly due to the very sensitive nature of the powerful drive: the structural panels offer a sufficiently generous impact tolerance, however, to make this work. Electrical usage (for stabilisation) is required only where there is no atmosphere - twin solar panels are deployed to ensure this doesn't drain the battery. Interestingly after taking off from Tylo the gentle ascent speed (10-20 m/s) continued up to c.2k, after which the high acceleration took over. Acceleration forces of 38G suggest this may not be the most comfortable way of flying. Craft file: https://kerbalx.com/dnbattley/Kraken-Drive-Mk3-Lite

I also just experimented with a k-drive design which successfully traverses the 300m barrier (whereupon it surges forward) and for some reason continues to accelerate even faster at higher altitudes. By LKO it has an estimated TWR of at least 15x or so. I'll post photos and the craft file tomorrow.

Surprisingly it is not particularly taxing, at least unless you crash. Most of my testing was done on a MacBook Pro 2015...

It may be good practice to demonstrate the feasibility of your challenge with a test design/alt-f12'd creation descending to Jool and highlighting its base requirements.

Might it not be prudent to unpin it then.... Mods?