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Hypography X Prize Entry


TheBigDog

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Another problem is that it is required from the craft to shoot a descent video... Not much problem for apollo style lander, but how would airbag lander get itself on camera during descent? Maybe if there would be a camera on that thruster part, but how could we then send off all that bytes. Oh of course, if lander would already have its systems on, then its as simply as radio comunication. Or maybe there would be uplink antena on that part, and maybe it could be made for that part to stay in orbit for a whine longer, maybe even a few orbits?

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Another problem is that it is required from the craft to shoot a descent video... Not much problem for apollo style lander, but how would airbag lander get itself on camera during descent? Maybe if there would be a camera on that thruster part, but how could we then send off all that bytes. Oh of course, if lander would already have its systems on, then its as simply as radio comunication. Or maybe there would be uplink antena on that part, and maybe it could be made for that part to stay in orbit for a whine longer, maybe even a few orbits?

 

Yeah, when I read that descent and landing video requirement, I realized that it just about killed the idea of an airbag landing. Too bad. With the airbag landing you didn't have to be too fine with it. You could have used off the shelf, solid propellent, throw-away rockets.

 

Now we have to do a "gravity turn" landing.

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We can do better than the 5.7 km/sec from LEO to moon orbit figure you give.

 

We do it like this:

 

From LEO we place the craft into an orbit with an apogee of 322464 km. This places it within the Moon's Hill sphere.

 

Delta v required: 3.088km.sec

 

From here, we do a burn that reduces the relative velocity between the craft and the moon to 0.068km/sec. this will place it in an eccentric orbit around the moon with a perilune of 1835 km (100km above lunar surface)

 

Delta v: 0.727 km/sec

 

At perilune, we do a braking burn to circulize the orbit.

 

Delta v: 0.643 km/sec

 

Total delta v to moon orbit: 4.458 km/sec

 

 

With our best present chemical rockets (ISP 450), this gives us a mass ratio of 2.75. (compared to a mass ratio of 3.6 for the 5.7 km/sec figure.)

 

A Taurus XLS launch vehicle can deliver a payload of 1900 kg to LEO (price tag 32 million), meaning you could deliver 691 kg to Moon orbit

 

An Athena I can get 1805kg to LEO for a price tag of 17 million, allowing you to get 656 kg to the moon.

 

For the bargain price of 10 million, the Eurockot can get 1850 kg (673 kg to moon orbit) to LEO, but you have to launch from Russia.

OK, lets assume we go with the Eurocket, but we name the lander Alice and use the Ralph Kramden mission profile of "straight to the moon". Instead of going into lunar orbit we just aim for the middle and go straight into descent. What does that do to our deliverable mass, and does it simplify the mission profile?

 

Bill

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Another problem is that it is required from the craft to shoot a descent video... Not much problem for apollo style lander, but how would airbag lander get itself on camera during descent? Maybe if there would be a camera on that thruster part, but how could we then send off all that bytes. Oh of course, if lander would already have its systems on, then its as simply as radio comunication. Or maybe there would be uplink antena on that part, and maybe it could be made for that part to stay in orbit for a whine longer, maybe even a few orbits?

 

hmm I got an Idea. We put a camera "drone" outside, say as a result of one of the stages breaking off and the camera falls into orbit or something, and the camera has little thrusters. maneuvering, thrusters that will allow it to watch the lander. or we just have another satellite or something take a picture.

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What would be the velocity of the lander if no propulsion were used to slow it?

 

If we can get to a low enough orbit and kill all orbital velocity would it be possible to just crash, using materials to absorb the impact? The materials available today are quite extraordinary. It might even be possible to to use a self hardening foam or lightly inflated compartmentalized system.

 

Keep the lander pointed down, and have 20 meters of absorbtion material between you and the surface. No bounce, just splat.

 

This system would likely vastly simplify the design of the lander, allow for simple simulation of the results, and (without fuel and motor requirements) perhaps allow fora greater payload?

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What would be the velocity of the lander if no propulsion were used to slow it?

 

If we can get to a low enough orbit and kill all orbital velocity would it be possible to just crash, using materials to absorb the impact? The materials available today are quite extraordinary. It might even be possible to to use a self hardening foam or lightly inflated compartmentalized system.

 

Keep the lander pointed down, and have 20 meters of absorbtion material between you and the surface. No bounce, just splat.

 

This system would likely vastly simplify the design of the lander, allow for simple simulation of the results, and (without fuel and motor requirements) perhaps allow fora greater payload?

 

But, you must consider some things, wont it make the lander weigh more? thus we need to have a bigger propulsion system.

Air weighs something in space I THINK.... but I know for a fact, foam ways more than air, in space or on the ground. And how much foam comes in a canister or bottle or w/e. How much do we need?

If we could make something like a honeycomb spring thing that has flexible honey comb compartments, then we might be able to. or something like that.

just giving u somthing to think about.

-Theory

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What would be the velocity of the lander if no propulsion were used to slow it?

 

If we can get to a low enough orbit and kill all orbital velocity would it be possible to just crash, using materials to absorb the impact? The materials available today are quite extraordinary. It might even be possible to to use a self hardening foam or lightly inflated compartmentalized system.

 

Keep the lander pointed down, and have 20 meters of absorbtion material between you and the surface. No bounce, just splat.

 

This system would likely vastly simplify the design of the lander, allow for simple simulation of the results, and (without fuel and motor requirements) perhaps allow fora greater payload?

Ever do one of those contests in HS where you have to drop an egg in a contraption that prevents the egg from breaking? This would be the same thing on a more expensive scale. I was toying with the idea of a penetrator that would be designed to go deep into the moon. Have the rover encased inside and it crawls out the back end and up to the surface. Fun ideas, but I think that the energy you need to absorb is just too high, and the variable of what you are hitting is too unpredictable. There is also the problem of having the Google committee approve your mission. :xparty:

 

Another thought though, given a worst case scenario of hitting way to hard, how much should we prepare our engineering to withstand? Target a 1 m/s descent landing, but be able to survive 10 m/s landing?

 

Bill

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(Bolding mine)

If we can get to a low enough orbit and kill all orbital velocity would it be possible to just crash, using materials to absorb the impact?

This system would likely vastly simplify the design of the lander, allow for simple simulation of the results, and (without fuel and motor requirements) perhaps allow fora greater payload?

How do you plan to: 1) insert the vehicle into a low orbit? and 2) kill all orbital velocity? without a rocket motor and fuel?

 

Recall we’re dealing with the moon, so neither aerobraking (practically no atmosphere) nor electrodynamic propulsion (practically no magnetic field) are available alternatives, leaving the possibility of some sort of mechanical braking by bouncing/glancing/dragging something across the Moon’s rugged surface at several Km/s. I don’t think there’s any material capable of withstanding that!

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But, you must consider some things, wont it make the lander weigh more? thus we need to have a bigger propulsion system.

Air weighs something in space I THINK....

If humans are weightless in space, why do you think air would have weight?

but I know for a fact, foam ways more than air, in space or on the ground. And how much foam comes in a canister or bottle or w/e. How much do we need?

 

I think foam would be totally ineffective in space. What gives it its "squishy" quality is the air pockets inside. In the vacuum of space, the air would be instantly sucked out, leaving you with a tiny, shriveled mass.

If we could make something like a honeycomb spring thing that has flexible honey comb compartments, then we might be able to. or something like that.

just giving u somthing to think about.

-Theory

 

I like the spring idea, but perhaps instead of a honeycomb, a Buckminister Fuller inspired idea might help on the actual shape of it. :xparty:

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Another thought though, given a worst case scenario of hitting way to hard, how much should we prepare our engineering to withstand? Target a 1 m/s descent landing, but be able to survive 10 m/s landing?

 

Lunar surveyors used gravity turn and killed their engine about three meters above the surface. Surveyor 3 actually bounced back in accident, and the first jump was 10 meters. It survived of course and it was not that rugged. So it survived about 4-5m/s crash.

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What would be the velocity of the lander if no propulsion were used to slow it?

 

If we can get to a low enough orbit and kill all orbital velocity would it be possible to just crash, using materials to absorb the impact? The materials available today are quite extraordinary. It might even be possible to to use a self hardening foam or lightly inflated compartmentalized system.

 

Keep the lander pointed down, and have 20 meters of absorbtion material between you and the surface. No bounce, just splat.

 

This system would likely vastly simplify the design of the lander, allow for simple simulation of the results, and (without fuel and motor requirements) perhaps allow fora greater payload?

Even if all the problems that other people have pointed out about his idea are rectified, there is still one problem and that is that this has never been done before. Which means lots of designing and testing - means more $$$, more than we would save from rocketless/simplified design im betting.

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Even if all the problems that other people have pointed out about his idea are rectified, there is still one problem and that is that this has never been done before. Which means lots of designing and testing - means more $$$, more than we would save from rocketless/simplified design im betting.

Could be. But good design does not need testing.

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If humans are weightless in space, why do you think air would have weight?

 

We are not weightless in space ;). You still way 110 in space :hihi: as you do on earth. But there is no way to measure weight because all of our weight measurement equipment uses gravity.

Air is made up of molecules that are to small to weigh, and gravity has a neglectable effect on them. or something like that. :doh: Does a pinch of dust weigh something? Of course. Can you feel the weight of it in your hand? no.

now imagine that space is actually NOTHING. if you put air into nothing, does that make nothing weigh something? because air is held in by the atmosphere and gravity, it must weight something.

 

you think it weights nothing because you breath it, walk through it and live in it all day long.

 

Sorry about that. I do not know why I was wondering if Air weighted something..... it is a little weight though maybe I was thinking about if air was compressed in a tank....

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We are not weightless in space :D. You still way 110 in space :) as you do on earth. But there is no way to measure weight because all of our weight measurement equipment uses gravity.

Air is made up of molecules that are to small to weigh, and gravity has a neglectable effect on them. or something like that. :) Does a pinch of dust weigh something? Of course. Can you feel the weight of it in your hand? no.

now imagine that space is actually NOTHING. if you put air into nothing, does that make nothing weigh something? because air is held in by the atmosphere and gravity, it must weight something.

 

you think it weights nothing because you breath it, walk through it and live in it all day long.

 

Sorry about that. I do not know why I was wondering if Air weighted something..... it is a little weight though maybe I was thinking about if air was compressed in a tank....

 

I think you are confusing weight and mass. ;)

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air weighs a fair amount actually, and yes compressed air gets heavier by volume. It's a lot like water in that the pressure in general goes up as you get closer to the center of the planet.

 

 

good design does not need testing.
ANd Murphy will laugh in your face. :)
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We are not weightless in space :D. You still way 110 in space :)
I think you are confusing weight and mass. ;)
I agree, with freeztar: Theory5, you appear to be confusing the concepts of mass and weight. The mass of a body is defined by the force required to accelerate it by a give value (Force = Mass * Acceleration) Weight is a measure of force – the force exerted on a body by one or more other bodies due to gravity. Near Earth’s surface the acceleration of gravity is about g = 9.8 m/s/s, so Weight = Mass * g. For example, the weight of a 80 kg person on Earth’s surface is about 784 N.

 

The acceleration of gravity in the vicinity of a large primary body such as Earth is give by [math]g = \frac{\mu}{r^2}[/math] (where [math]\mu[/math] is the Earth’s standard gravitational parameter). So a body in Earth orbit does have weight. An object in a low earth orbit 350,000 m above the surface (which is about 40,075,020 m above its center), then, has about 98% of its surface weight. At a higher, “medium” orbit of 3,500,000 m, it’s about 85%, at a geosynchronous orbit of 35,786,000 m, about 28%.

 

Because objects in orbit are in free fall, they don’t experience their weight as an opposing force with the ground, which is why they are commonly, but incorrectly, referred to as “weightless”

 

Units of mass and weight are confused in most nonscientific language. People commonly use kilograms as a unit of weight, when they should use Newtons. In the peculiar English/American system, pounds are both a unit of mass and force - units used only for mass in this system are very obscure – the slug (1 pound = 1 slug * 1 foot/second/second) and the blob (1 pound = 1 blob * 1 inch/second/second) – all the more reason, IMHO, not to use this weird old system if you can avoid it. ;)

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