Hypography X Prize Entry

[Jay-qu]

170kg thats great

I got emailed the official guidelines this morning. I will attach them to this document.

NOTE these are not set in concrete and may be subject to change, until jan 2009, up until then anyone can make suggestions to change these guidelines to help make them more fair and iron out any loopholes.

[TheBigDog]

I am looking at a 4wd electric monster truck as my starting point. I am going to remove every cosmetic feature on the thing, reducing it to a remote controlled moving platform. I am going to fashion an array of batteries instead of the single one that it normally runs on. My goal is to give it a range of 10 km on a single charge, twice the distance requirement for the range bonus.

Control will be as follows: we will have a website that is actually hosted by the lander. From there we will be able to look at live camera shots from the rover, and issue commands to the rover. A command can be a series of maneuvers. We might tell it to turn 30 degrees, then move forward for 30 meters. It will begin the maneuver and continue until it is complete, or until it either gets a signal to stop. When it stops we will evaluate the position and send a signal for the next move. The lander will have a wheelbase of about half a meter. It will have a mast that extends up where the antenna for communication with the lander will be located. There will also be a probe used for recharging. I am considering having the lander able to auto guide the rover to the recharger, so once we get it close it can do the final distance with precision.

We can indicate what type of photography for it to take along the way. It will have the low resolution navigation cameras on all the time, but we can choose to activate the HD camera and give it specific instructions as needed. The HD camera will be used for the HD movies, panoramic shots, and extreme close ups. All photography will be stored locally on the rover and uploaded to the lander. The lander will then relay the files back to earth through it's website.

My goal is to be able to complete the requirements of the mission on the initial charge in the rover, and the initial charge on the lander. If the solar panels fail to deploy on the lander, or the recharger fails to function, we will still have a successful mission and qualify for the prize. Assuming that those systems don't fail we then aim at the bonus prizes.

There will be four rovers, so we have ample opportunities, even room for friendly competition on the team. We should be able to control all the landers simultaneously.

My vision of the lander is the Eiffel Tower. Tall with four feet in a wide stance. It will unfold itself in space and fall feet first toward the moon. The rovers will be attached under the center of the lander and lowered or dropped the last distance to the surface after we have touched down. The top or the tower will be the comm antenna for controlling the rovers as far out as possible. The solar array for the lander will be as high up as we can keep it. There will also need to be a high gain antenna that points at earth for communications. The solar array on the lander should be large enough to run the main communications, with enough excess to charge the landers. I think that we should actually have a large array of batteries on the lander so it is always in the act of charging the low ones. We then run of charged batteries and even recharge the rovers from charged batteries as needed. This of course is all open to debate.

All systems will have some automation. The solar array should be able to rotate for best angle to the sunlight. Just before it loses sunlight it should rotate into position for when the sun comes back into view and wait. When the sun warms the equipment and begins charging things everything will wake up again. This too can be on a timer as we will know pretty much exactly when it is going to happen. The rover I build will have a fail safe in case it loses contact with the tower. If it determines that it has been out of contact for a default time it will plot a reverse course to the lander and self navigate until it restores communications. It will be using low powered signals to transmit telemetry to the lander, the antennas on earth should be able to snoop on those signals, so if the rover cannot regain contact with the lander we should be able to at least observe what it is trying to do to regain contact. This of course can all be tested prior to launch.

But I am getting way ahead of myself. I went out today and looked at various RC cars to use as a base. Lots to learn and lots to do. Before any of that I need to finish cleaning the garage and build myself a good workshop.

This is too much fun!

Bill

[Janus]

Originally Posted by TheBigDog

What if we go Apollo style instead of airbags and rocket straight to the surface? There is a randomness to the airbag landing that really bothers me.

Bill

From what I can figure, you could land about that same 170 kg.

The problem is that that 170 kg includes the landing motor, landing gear, fuel tanks, atitude control system, and the additional frame work to mount them to.

Plus the need for a much more sophisticated landing control system.

Leaving us with a much smaller "working" payload delivered to the Moon.

[Roadam]

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?

[Janus]

Originally Posted by Roadam

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.

[TheBigDog]

Originally Posted by Janus

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

[Roadam]

If people at Eurockot could be persuaded to extend the third stage fuel tank and give our craft direft push to the moon(that 3 km/sec delta v), it would save us some heavy structure... Of course that would also limit our launch windows...

[Theory5]

Originally Posted by Roadam

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.

[Kayra]

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?

[Theory5]

Originally Posted by Kayra

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