Eeloo Exploration Rover... for $9915

[koshelenkovv]

Yes, full cost of mission is $9915. Rocket consists of 28 parts and weights 25 tons.

I've done this mission as part of my own challenge ($100 000 space program). It was hard and had unexpected complications, but I've overcome its.

I really proud how it all came off

So I reposting flight report here too.

Here a rocket. Looks pretty, isn't it? It flexes at the launchpad like a spring.

But I know how to fly rubber rockets and almost had not have problems delivering it to orbit.

Liftoff!

I started LV-N, because without it rocket is uncontrollable. Anyway, at altitude of about 2km LV-N will have Isp higher than aerospikes.

It requires constant manual control and very gradual gravity turn or it will flip over. But this inconvenience lasts only for two minutes before staging occurs

Staging is slightly tricky. Upper part must be released when a tiny bit of fuel still left, and then it flies away on aerospikes.

(it's hard to simultaneously control rocket, watch for fuel, stage in right moment and make good screenshot of this)

Continuing ascent on nuke alone.

On LKO with over 7000 m/s dV left.

From this moment mission went awfully wrong.

First, plane correction ate 1200 m/s dV. In my first reconnaissance flight it was 1100 m/s, for second time it was a modest 300 m/s. I've lost 100 m/s on this.

Second, it seems that I will arrive too late.

After tweaking and fiddling with maneuver nodes I've managed to make correction at a price of extra 250 m/s.

And new surprise! Getting into orbit now costs enormous 2400 m/s dV.

First time I flew at Eeloo it was 1600, second time it was 1900 m/s. WHY so much right now?!

Looooong buuuuuurn is soooooo loooooong...

And finally! I'm in orbit with feeble engine and poor TWR and have only 1072 m/s of dV left.

Then SUDDENLY I've realised that I orbiting Eeloo opposite to its rotation. Bye-bye another 140 m/s dV.

The task: to land with 930 m/s dV with TWR slightly over 2.

For example, killing miserable 50 m/s of velocity will take only 22 seconds. Only.

I've killed all orbital velocity then all horizontal velocity and paused. Now I falling from 15 kilometers at 200 m/s and have only 500 m/s dV or 131 seconds of burn time left.

But it's enough for landing if I'll do it properly. VERY properly.

I've decided to make a suicide burn. Table shows altitude my ship must have to cancel any given velocity right before touchdown and how much burn time it will consume.

It went as planned. I have 200 m altitude margin.

Landed!

The I've switched to Space Center and when I've switched back something very nasty occurred: lander have fallen through the planet surface and falling to its center.

So, I was forced to repeat this nerve-whacking procedure.

It went not as smooth as first time. I ran short of 200 meters. Lander met the surface at 30 m/s and exploded, sending rover in flight. I quickly retracted solar panel in hope that it will not break and leveled rover in such a way that it will land on wheels, which have at least some suspension. Rover landed and decoupler underneath of it exploded, sending him in second, shorter, flight.

Luckily, nothing else got broken.

Sorry, no screenshots of all this madness, I was too busy saving poor little thing

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... AND SOOOO ...

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Meet Equilibrium, the Eeloo Exploration Rover!

Here he is, running downhills...

Jumping happily...

Contemplating the sunset.

[Wayfare]

I've seen minimalistic rover designs before but that, sir, takes the cake. Great work!

[DMagic]

Wow, fantastic efficiency in all stages of this design. That's what, six parts on that rover? Does it actually stay upright, or do you have to keep moving to keep it stable?

About that delta-v to capture at Eeloo, I think the difference is due to where in its orbit you are encountering it. Further away it should take less to get into orbit right? That's why Moho is such a beast to get into orbit around; it's so close to the sun. Also, from your screenshot, the your orbit intersects Eeloo's very far away from your apoapsis. You are going the slowest right at the peak of your orbit, so getting into orbit around another planet at any other time requires a lot more delta-v.

Edited May 22, 2013 by DMagic

[koshelenkovv]

Wow, fantastic efficiency in all stages of this design. That's what, six parts on that rover?

Seven - core, 2 wheels, solar panel, battery, cubic strut and antenna. Antenna and, theoretically, battery can be removed, but rover looks better with them.

Does it actually stay upright, or do you have to keep moving to keep it stable?

Moving does not matter, it falls anyway. But it falls really slow. Rover weights 176 kg on Kerbin and only 30 on Eeloo - it is so light and Eeloo gravity is so small that force of tiny internal SAS gyroscope is enough to keep it upright for few minutes.

I drive it with two hands - IJ for rover controls forward and backward, QE to steer (strangely, it cannot steer by the only two wheels), and occasionally WS to correct tilting on slopes or if tilt become dangerous.

The lid of solar panel must never touch ground on a speed, or it shatters. Rover can lean on it when staying on brakes (this is parking position).

Forward part is more rugged and can withstand impact with ground up to 15 m/s. Wheels survived several hops at over 20 m/s.

Edited May 22, 2013 by koshelenkovv