Kaku II: Probe to Jool, and to orbit all it's moons.

[SunJumper]

In planning is a probe that will break into six to explore all of Jool's moons, with one to go into Jool's atmosphere.

The current design I'm considering is the flat OKTO, engineered to contain a small RTG, then two xenon tanks and an ion engine, powered by two Gigantor solar panels. Also attached are two antennae, assuming they can send signals as well. All parts will be slightly engineered to improve performance by a small amount (so that I will not require a 200 ton launcher).

Before I send that design, I'll send a pioneering probe to test the solar irradiance at Jool, and if it is sufficient, the Kaku II design will go ahead. The pioneering probe will mass about 400kg, and the combined Kaku II probe will mass at least 6000kg.

I will be using parts from the KW Rocketry pack as well as stock parts, and the engineered parts.

As for the Kaku I, it was a probe that was much smaller and much less capable, it missed the aerocapture, having lost contact 1,230,000km from Jool. Systems went online, to find the periapsis out at Pol. The capture was costly, leaving 200m/s in the tank, the craft executed a flyby of Pol, and is doing remote Joolian research. It was thought that an error in the autopilot's programming caused the incident.

And yes, this probe is named after Michio Kaku.

Edit:

I give up. The game is too buggy for me to launch such a mission.

Edited May 1, 2013 by SunJumper

[BossSquirrelz]

Nicely named after a brilliant man. Interesting mission plan, too!

[M5000]

Sit on down, It's story time with M5000 and some advice for a probe to Jool mission..

I actually did a Jool mission a while ago with the Iasillo-I probe.. It was supposed to be a mapping mission so I sent out a probe with like 4 or 5 of the larger KSPX Xenon tanks and then like 8 of the smaller 500-unit KSPX Xenon tanks, had something in the neighborhood of like 16Km/s of Delta-V... The probe itself was absolutely loaded with sciency stuff and mapping equipment and all kinds of bells and whistles, so had the mission gone better, I'd have all of the Jool system charted out.. Yeah but about that solar power far out at Jool....

Many problems occurred..

I used the KSPX larger ion engine which takes more electricity... So...

I didn't have enough solar power to be able to run my ion engines at full throttle no matter where I was, it would ALWAYS drain from the battery by some amount. (PUT A LOT OF SOLAR PANELS ON THERE. You are further out and it will have less sunlight to get to the probe.. So...

I had to run my ion engine at no more than 20% throttle at any given point, or the battery would begin to drain. I could run it in full-throttle bursts, but most of the burn had to be done at 20% throttle... So....

The burn times for even a small burn took about 4 in-game hours, no lie. About an hour or so on X4 physwarp. So....

Obviously I'm not gonna be making any quick corrections if something goes awry, of course in Kerbal spirit, that's exactly what happened. I found out I was going the wrong way in orbit around Jool AFTER I had already slowed down from my injection burn and obtained some form of a stable orbit. Reversing the direction would have taken pretty much all of my delta-V and a huge burn time, so I decided to try and roll with it, maybe slingshot around one of the planets and fix my direction... So....

As I come up on Pol, the first target, I'm going much faster than I ever thought I could. My encounter time was about 15 minutes as opposed to the normal 1-3 hours or so. A single ion engine at 20% or less throttle with a heavy, fuel and battery loaded probe armed to the teeth with science stuff being able to slow down from twice of Joolian orbital velocity down to Pol orbital velocity in 15 minutes? Not gonna happen. I flew right on by.. So....

I kept going, passed up Bop and had some fun, took some pictures to send back home via a tacky postcard saying "Wish you were here....No really, someone needs to come here and help me reverse my orbital direction, your insertion burn sucked!" So....

I went to my current favorite planet that I've only touched once, Vall. So I've got my beautiful encounter lined up and then I get this:

Oh.. Looks like I was just a tiny bit too precise with my maneuvers.. So...

This happened..

Then this happened:

And now I have a lovely desktop background...

The moral of the story is: Do your insertion burn correctly, and put more solar panels on your ion probes and spacecraft, because ion engines are hungry and greedy bastards. Like, whatever you think is going to be enough, solar panels, you probably need like twice as many.

[Murchadh]

I was building a sat/probe/launcher for Duna and then noticed that Jool is coming up slightly before Duna and had the "bright" idea to double the mission to both. The sat/probe has ~10k dV (ion) attached to a nuclear inserter (~6k dV). I actually redesigned the inserter to give it more oomph specifically for Jool but now you guys are giving me second thoughts. I totally like the idea of multiple cores for Jool and already have a design in my head for how I can further adapt the inserter to have a bunch of probe/sats peel off from side mounts. My probe/sat design weighs ~0.9t currently and I thought I seemed fine but maybe I should add moar solar panels (serves me right for testing the thing around Kerbin and not further away from the sun *facepalm*) ... but that would propabbly mean redesigning the probe/sat completely to be able to fit extra panels ... or I could just like go with a bunch of totally "expendable" probes. Like a MIRV, only less dangerous (or more... depending on which Kerbal you talk to). I think I can fit 12 onto my inserter, shoot them off into multiple trajectories once I get to Jool and go for the fire, forget, hope and pray approach... I mean since I have never been to Jool, might as well see what happens and let it be a surprise.

Anyway thanks for the ideas and tips.

PS> I totally love Kaku. He reminds me of my university Philosophy prof, he always looks like he knows something that no-one else does... (which he does) ... and enjoys the fact that he does.

[magnemoe]

If you want to carry sub probes I recommend nuclear engines. Ion engies don't like carry lots of payload. One option is to do like M5000 and have one probe who jump from moon to moon. I did an probe all mission, lander failed on Val an Tylo else the project was successful.

Have started an new game and plan to repeat it in much smaller scale, 400kg rovers over 1 ton for one, not including Tylo as target.

[SunJumper]

That's why I'm having six ion engines, one for each probe. I'll play with the Ant too.

[Murchadh]

@magnemoe: That is exactly what I am doing. Each probe has its own ion engine but the whole lot is carried by a "mothership" with a big fuel tank, sporting nuclear engines.

[SunJumper]

Well, the ion system is a go. The Pioneer has some 1300m/s left, and can probably make it to a Tylo orbit.

Funnily enough, 4:30AM today I built a design that brings 16km/s to Jool. It's in polar Laythe orbit now. Did I mention I'm aiming for a polar orbit on every body?

Edited April 29, 2013 by SunJumper

[M5000]

That's why I'm having six ion engines, one for each probe. I'll play with the Ant too.

I would never use the ant unless your plan on sending up a lot of fuel. The ISP is pretty much the worst of any engine in the game, worse than the Mainsail I think, even. I think the only thing that's worse with ISP is the SRBs... They produce no more thrust than an ion engine yet have a horrible ISP.

[SunJumper]

For small probes, I've managed to get up to 1.5km/s with the ant. It's useful for landing on bodies even as big as Vall.

But this doesn't matter as I'm using Ions anyway.

[hugix]

I made a mapping satellite for the entire Jool system based on the Cassini Huygens design.

It consisted of two parts. the main probe. With ISA mapsat and some other gizmo's. And a lander probe consisting of some battery's a chute and some science gizmo's doomed to make a soft landing on Laythe. the huygens probe.

After a perfect watery landing I went further to explore the system with Cassini. It was a blast. Except for the smallest moon I got all mapping info with ISA. (Except for some polar regions due to inclination changes for the next moon). I even got to crash the Cassini probe on Tylo. Which was very cool!

The probe entering the Joolian system

The huygens probe making it's way down to the Laythean surface (or Laythean waters)

Water it is

First encounter with Tylo

six probes is a cool idea but there is a lot that can go (will go) wrong! I learned a lot from my mission, I would suggest you do the same. The Joolian system is very crowded and complex. Be sure you know how to handle yourself.

[magnemoe]

I'm working on an follow up mission to Jool. With the new rover wheel I wound I could put wheels on an small fuel tank, and get an 1000m/s delta-v from an 500 kg lander/rover, almost 3000 m/s from an one ton one, how is overkill except on Tylo. Guess an drop tank would be better for this.

[SunJumper]

I'm working on an follow up mission to Jool. With the new rover wheel I wound I could put wheels on an small fuel tank, and get an 1000m/s delta-v from an 500 kg lander/rover, almost 3000 m/s from an one ton one, how is overkill except on Tylo. Guess an drop tank would be better for this.

I have a feeling you could orbit all the moons with 3 to 4 km/s, with sufficient flybys...

[magnemoe]

I have a feeling you could orbit all the moons with 3 to 4 km/s, with sufficient flybys...

Probably, for an minimum cost do an Laythe aerobrake, hohmann to Val then to Tylo, not sure if its best to do Bob or Pol first.

However if you want to drop rovers on all worlds this increase the mission profile a lot so lighten them gives an serious boost.

Thinking 1000m/s for Laythe, 2000 for Val, 4500 for Tylo and as small as possible for bob an pol.

[SunJumper]

I think one should visit Tylo first. If possible, use a Tylo gravity assist to capture into a Jool orbit, maybe even into a hohmann to Pol. Maybe one Pol boost (they are surprisingly effective) or two, capture at Pol. Escape Pol, Oberth to Bop, assist to remove some velocity, brake.

But whatever you do, if you're doing everything with one craft, visit Laythe last.

[SunJumper]

Also, never forget to correct your periapsis every time you enter a SOI.

[Boris_T_Roach]

For all your probing needs in a multi-moon system , BtAC industries can offer you no finer system that the original 'multiprobe'

However this is the slightly cheaper older version

The new version (no screen shot available as yet) holds 4 mapping capable probes of the same design, complete with their own mechjeb units to make navigation easier, and not the 1200 Dv of the mk1 probes

pictured, but an amazing 2300 Dv per probe, plus landing gear, parachutes, solar panels, RTGs, and a full suit of sciency type bits and bobs.

The carrier ship has been modified so it can arrive in the Jool system with about 1800 Dv left after braking into a Joolian orbit outside Tylo ready to deploy the probes either inwards or on a moon hopping flight to the outer moons

Remember , this design has enough Dv so that it does not need to do dangerous aero-braking manuvers to get into Jool orbit, with all the risks that involves, but arrives safely, calmly and ready to do science.

The only downside is that it needs to be launched in 3 sections from KSC and docked in orbit before it is ready to go do stuff

Boris

[SunJumper]

For all your probing needs in a multi-moon system , BtAC industries can offer you no finer system that the original 'multiprobe'

However this is the slightly cheaper older version

The new version (no screen shot available as yet) holds 4 mapping capable probes of the same design, complete with their own mechjeb units to make navigation easier, and not the 1200 Dv of the mk1 probes

pictured, but an amazing 2300 Dv per probe, plus landing gear, parachutes, solar panels, RTGs, and a full suit of sciency type bits and bobs.

The carrier ship has been modified so it can arrive in the Jool system with about 1800 Dv left after braking into a Joolian orbit outside Tylo ready to deploy the probes either inwards or on a moon hopping flight to the outer moons

Remember , this design has enough Dv so that it does not need to do dangerous aero-braking manuvers to get into Jool orbit, with all the risks that involves, but arrives safely, calmly and ready to do science.

The only downside is that it needs to be launched in 3 sections from KSC and docked in orbit before it is ready to go do stuff

Boris

Yeah, I would rather the payload at Jool to be 10t or less...

[magnemoe]

I would never use the ant unless your plan on sending up a lot of fuel. The ISP is pretty much the worst of any engine in the game, worse than the Mainsail I think, even. I think the only thing that's worse with ISP is the SRBs... They produce no more thrust than an ion engine yet have a horrible ISP.

Downside is that ions needs an 300kg solar panel to be useful and they weight 250kg themselves, nice for long range multiple target missions. Not for an satellite you deploy in orbit, here the ant and an oscar tank or two is perfect. for orbital adjustments. if you want to map target and move on the ion is usually better.

This rover and lander weight 530 kg, and can land on any light gravitation moon or place with atmosphere. add an toroidal tank or two and it can land everywhere except Tylo and still weight less than a ton. it uses the ksp-x in line version of the small radial engine.

[SunJumper]

I've decided to use an Ion engine based design for each sub-probe, that mass 760kg each. This makes for a Jool payload of about 8t.

[M5000]

Downside is that ions needs an 300kg solar panel to be useful and they weight 250kg themselves, nice for long range multiple target missions. Not for an satellite you deploy in orbit, here the ant and an oscar tank or two is perfect. for orbital adjustments. if you want to map target and move on the ion is usually better.

The ant is, admittedly, okay for a small landing engine for a one-time use probe, rover, or lander, but for anything that stays in orbit, or you need to have operational for a long time, the ion engine is the only way. That little rover you have is nice, but after it loses its fuel and hopping ability, what next? Ion engines can actually provide sufficient thrust for landing engines if the craft is light enough, which it is entirely possible, assuming you're on a small, non-atmospheric moon. (Mun, Minmus, Gilly, Bop, Pol, Eeloo possibly, You get the idea..)

[SunJumper]

The ant is, admittedly, okay for a small landing engine for a one-time use probe, rover, or lander, but for anything that stays in orbit, or you need to have operational for a long time, the ion engine is the only way. That little rover you have is nice, but after it loses its fuel and hopping ability, what next? Ion engines can actually provide sufficient thrust for landing engines if the craft is light enough, which it is entirely possible, assuming you're on a small, non-atmospheric moon. (Mun, Minmus, Gilly, Bop, Pol, Eeloo possibly, You get the idea..)

Actually, Ion Engine landings are impossible on the Mun and Eeloo, and incredibly impractical on Minmus and Bop.

[Tw1]

My Jool probes so far have been massive stacks of xenon, with plenty of batteries, and large solar panels, and the extra powerful ion engines from the pack on spaceport, which makes things easier, but less challenging.

Longer means more room for the sub-probes, and the Jool diver probe.

The sub-probes are as light as possible, and use RCS to land. Except for ones made for Tylo...

M5000, it is such a pity your probe was stuffed my a mistake like getting the wrong direction around Jool! May your next one do much better.

I also suggest planning your mission in a way that heavier things, (like tylo lander-probes) are dropped sooner rather than later, to maximise thrust and Delta V. And doing it from inner moons to outer moons, as a general rule.

That's the plan at least...

Edit: Pics!

With panels retracted. The LV-909 belongs to the Tylo lander.

My earlier one. That's a Fl-800 filled with xenon and batteries. It was overpowered when I downloaded it, and probably could do with a bit more cutting down before I get there.

With all those engines, it will be highly reliant on that internal battery.

The rover probes on both are cart mod based, both of these were launched pre-0.19

Edited May 1, 2013 by Tw1

[SunJumper]

My Jool probes so far have been massive stacks of xenon, with plenty of batteries, and large solar panels, and the extra powerful ion engines from the pack on spaceport, which makes things easier, but less challenging.

Longer means more room for the sub-probes, and the Jool diver probe.

The sub-probes are as light as possible, and use RCS to land. Except for ones made for Tylo...

M5000, it is such a pity your probe was stuffed my a mistake like getting the wrong direction around Jool! May your next one do much better.

I also suggest planning your mission in a way that heavier things, (like tylo lander-probes) are dropped sooner rather than later, to maximise thrust and Delta V. And doing it from inner moons to outer moons, as a general rule.

That's the plan at least...

I'd like to point out that my plan didn't involve landing on anything. The above photo shows me landed on Pol for the Rule of Cool. It wasn't even a part of the mission.