Air. Shelter. Water. Food.

RobertDyck · 2017-05-06 00:33:31

Dook wrote:

RobertDyck wrote:
And so it continues: Dook vs The Mars Society
That would be a good movie script, kind of like the movie "Rudy".
Dook would be played by Brad Pitt.
RobertDyck would be played by the Matrix Revolutions Trainman guy, Bruce Spence.
Oldfart would be played by a Marty Feldman lookalike.

No, Dook would be played by a Marty Feldman lookalike.

I looked up Bruce Spence on IMDB; he had a busy career. I'll take that as a compliment. However, people who know me claim I look more like John de Lancie, who played "Q" on Star Trek.

Last edited by RobertDyck (2017-05-06 00:38:26)

Terraformer · 2017-05-06 04:04:56

Also, Frank Simmons in Stargate: SG1, and Discord in My Little Pony: Friendship is Magic. I guess this means you'd be a villainous character then, Robert?

I'm still waiting to find out how long Dook thinks Earth will be willing to maintain a base on Mars, shipping every single thing that's needed (food doesn't actually mass that much, ~200kg of staple carbohydrates per person-year, so why not ship staples if you're going to ship everything else?). I'm getting the impression that he thinks it will happen for centuries...

Dook · 2017-05-06 09:38:01

Terraformer wrote:

Also, Frank Simmons in Stargate: SG1, and Discord in My Little Pony: Friendship is Magic. I guess this means you'd be a villainous character then, Robert?
I'm still waiting to find out how long Dook thinks Earth will be willing to maintain a base on Mars, shipping every single thing that's needed (food doesn't actually mass that much, ~200kg of staple carbohydrates per person-year, so why not ship staples if you're going to ship everything else?). I'm getting the impression that he thinks it will happen for centuries...

How long will we be willing to maintain a base on Mars? If they are successful, for more than centuries. When would you get tired of sending supply rockets to Mars?

Being successful is:
Not having anyone die
Being able to grow enough food for themselves
Having the life support and power equipment work well with the crew able to maintain the systems without the need for emergency missions to send new equipment

If they can't achieve the above things then criticism of the mission would grow and they might have to come home.

If a Mars base was successful the only thing they would need would be a small shipment every two or three years of spare and repair parts, some extra unique food, new laptop computers full of new entertainment.

Terraformer · 2017-05-06 10:51:49

Plus replacement people, as people come home. Or are you imagining them being one way missions, of people too old to have children because we can't afford to have kids there?

When would you get tired of sending supply rockets to Mars?

When would you get tired of sending human missions to Luna? For the US, it takes about three years.

RobertDyck · 2017-05-06 11:29:30

Terraformer wrote:

Also, Frank Simmons in Stargate: SG1, and Discord in My Little Pony: Friendship is Magic. I guess this means you'd be a villainous character then, Robert?

When I attended the local science fiction convention and some people claimed I look like "Q", at first I took offence. He's the villain! However, after a while I just went with it. Bought a Star Trek TNG shirt with rank insignia claiming to be captain, just like "Q". Wear that with dress shoes, black pants, black T-shirt under the costume shirt, and a flip-phone on my belt that happens to look similar to a TNG tricorder. It's a way to have fun.

When I was a child some people asked which TV show character I want to be. I didn't want to be any character, I wanted to be more like Albert Einstein. But if I have to be any character, my favourite show as Star Trek, and if I had to choose a character from that show I would pick Zefram Cochrane, who lead a team of engineers who invented warp drive and built the first warp ship. My last name is Canadian, spelled "Dyck" but pronounced "Dick". That character's last name is "Cochrane". So I'm not a cock, I'm a dick. Close enough.

Terraformer wrote:

I'm still waiting to find out how long Dook thinks Earth will be willing to maintain a base on Mars, shipping every single thing that's needed (food doesn't actually mass that much, ~200kg of staple carbohydrates per person-year, so why not ship staples if you're going to ship everything else?). I'm getting the impression that he thinks it will happen for centuries...

Apollo took one presidential election. JFK strongly advocated Apollo to beat the Soviets. As GW Johnson points out, his vice president LBJ was actually the big space fan. LBJ continued the work when he became president. But the very next president, the first president of the opposite party, was Richard Nixon. He said publicly that he thought Apollo was a "ridiculous stunt". He campaigned that he had a secret plan to end the Vietnam war early. Turned out his plan was to cancel Apollo, gut NASA, give the money to the military for a "surge" in Vietnam. If you remember, it didn't work. But NASA has never recovered.

Richard Nixon was inaugurated in January 1969. Apollo 17 was the last flight to the Moon: December 1972. Yup, Terraformer is correct, it only took 3 years for America to stop supporting the Moon.

Last edited by RobertDyck (2017-05-06 19:04:11)

Oldfart1939 · 2017-05-06 11:41:53

Robert-

Also entering this picture was the hatred by Nixon of all things Kennedy. He felt that the 1960 election had been stolen from him by JFK. So...belated revenge by shutting down that legacy.

Looking at things differently, through the lens of hindsight--Apollo wasn't really designed to be a sustainable program, but a quick & dirty Flag & Footprints demonstration of technical superiority. Those were my Grad School years.

Dook · 2017-05-06 11:59:46

Terraformer wrote:

Plus replacement people, as people come home. Or are you imagining them being one way missions, of people too old to have children because we can't afford to have kids there?
When would you get tired of sending supply rockets to Mars?
When would you get tired of sending human missions to Luna? For the US, it takes about three years.

I think settling Mars should be a one way mission but I know NASA won't be able to do that.

Having to make rocket fuel on Mars means you have to get a tremendous amount of Martian ice and get the salt out of it. It's just not easy enough to do and the water that a settlement does get it will need for drinking and watering plants.

The people sent to settle Mars would not be old. They would be around 22 years old, just out of college. I don't think they should be able to have kids on Mars.

When would I get tired of send human missions to the moon? The Apollo Missions served their purpose. We don't need to go back to the moon. How many people did we leave there? It's the moon, what's interesting about it?

Last edited by Dook (2017-05-06 12:00:18)

Terraformer · 2017-05-06 12:43:53

Many people didn't get tired of human missions to the moon. They still got cancelled.

I've seen some crazy ideas on here - came up with quite a few myself - but a centuries government Mars mission has got to be one of the craziest.

Dook · 2017-05-06 12:55:45

Terraformer wrote:

Many people didn't get tired of human missions to the moon. They still got cancelled.
I've seen some crazy ideas on here - came up with quite a few myself - but a centuries government Mars mission has got to be one of the craziest.

No President or congress could cut the funding to a Mars settlement and allow them to die.

Could they bring them home and end the mission entirely? Yes. That would absolutely happen if settlers are not able to produce enough oxygen, food, and water, or if any of the crew died.

This is why I am so against inefficiency and trying to collect regolith or ice on Mars and trying to ship everything like forges, 3D printers that don't provide life support. Those things increase the risk of mission failure. The mission is survival, not the production of metal shelf brackets.

A centuries long government mission is one of the craziest ideas you've ever heard? When have humans ever stopped exploring? What day did that happen?

louis · 2017-05-06 14:17:53

Boil and condense...what's the problem?

Dook wrote:

Terraformer wrote:
Plus replacement people, as people come home. Or are you imagining them being one way missions, of people too old to have children because we can't afford to have kids there?
When would you get tired of sending supply rockets to Mars?
When would you get tired of sending human missions to Luna? For the US, it takes about three years.
I think settling Mars should be a one way mission but I know NASA won't be able to do that.
Having to make rocket fuel on Mars means you have to get a tremendous amount of Martian ice and get the salt out of it. It's just not easy enough to do and the water that a settlement does get it will need for drinking and watering plants.
The people sent to settle Mars would not be old. They would be around 22 years old, just out of college. I don't think they should be able to have kids on Mars.
When would I get tired of send human missions to the moon? The Apollo Missions served their purpose. We don't need to go back to the moon. How many people did we leave there? It's the moon, what's interesting about it?

Dook · 2017-05-06 14:33:00

louis wrote:

Boil and condense...what's the problem?
Dook wrote:
Terraformer wrote:
Plus replacement people, as people come home. Or are you imagining them being one way missions, of people too old to have children because we can't afford to have kids there?

When would you get tired of sending human missions to Luna? For the US, it takes about three years.
I think settling Mars should be a one way mission but I know NASA won't be able to do that.
Having to make rocket fuel on Mars means you have to get a tremendous amount of Martian ice and get the salt out of it. It's just not easy enough to do and the water that a settlement does get it will need for drinking and watering plants.
The people sent to settle Mars would not be old. They would be around 22 years old, just out of college. I don't think they should be able to have kids on Mars.
When would I get tired of send human missions to the moon? The Apollo Missions served their purpose. We don't need to go back to the moon. How many people did we leave there? It's the moon, what's interesting about it?

Boil and condense what? For what?

Did you post a reply here that was meant for a different topic?

kbd512 · 2017-05-06 15:22:43

Dook wrote:

The issue isn't the weight of the powder vs the part but the combined weight of all the parts that don't get used? Why wouldn't a new filter get used? Or new bearings? New acid plates for batteries? New o-rings for the accumulators? New electric motors? New vacuum pumps? New fan motors? New P sensors? Why wouldn't a new motherboard or hard drive get used? Are you saying those things will somehow last forever on Mars?

Component and System Operating Life

Nothing is going to last forever on Mars. Some things will last a lot longer than others. Seals and bearings are good examples of things that typically last a long time and don't weigh very much, so it'd be a good idea to take replacement parts manufactured on Earth. A printer could actually recondition the seals with less media mass and negate the need to bring multiple replacements, but let's go with the assumption that whatever is light and therefore cheap to bring should be brought. There haven't been many seals or bearings replaced aboard ISS and the temperature extremes and cycle frequency are even greater than on Mars, but ISS is not subject to the abrasive dust in the Martian atmosphere.

3D Printing Technology

3D printers of the sort I envision are light, therefore cheap to bring, and should be brought. The media will weigh more than the print heads by a substantial margin.

Robotics Technology

We're going to bring DARPA / NASA / General Motor's Robonaut 2 or R2 or probably NASA's new Valkyrie by the time we're actually ready to go to Mars. R2 is aboard ISS right now. Robots like R2 can handle tasks that are dangerous for humans to do or require extreme precision to accomplish. Space walks and 3D printing are good examples. The tasks R2 performs aboard ISS include manipulation of avionics and electronics, assembly / disassembly of equipment like avionics and life support systems using hand tools, interfacing with computer systems to run diagnostics, communicating problems to humans and mission control, and eventually space walks (requires thermal management upgrades to the chassis. More than two decades of development and testing are incorporated into this family of technologies.

Robonaut R2 Homepage

Robonaut 2 NASAfacts

Robonaut 2 NASAfacts Updates

R2 was designed by GM and NASA as a modular family of systems to perform tasks in space to assist humans. When R2 is attached to Centaur 2, R2 performs the same tasks your Marscat performs. Centaur 2 contains four 9.9kW electric motors and an adjustable center of gravity. Apart from the upper half of R2, Centaur 2 also mounts a removable bucket, dozer blade, or drill on the other end. When R2 is attached to Spider, which as the name suggests is a robotic lower appendage for R2 that has 8 legs and moves like a spider, to move across terrain that would be impassable for a wheeled vehicle like Centaur 2. In any event, we already have a robot to attach the print heads to.

Robonaut 2 weighs 490lbs with its legs attached. I think Centaur 2 is around 1,500lbs. Both can be tele-operated using VR or autonomously operated, combined (R2 torso attached to Centaur 2) or separate (Centaur 2 does its own thing). Valkyrie is only 300lbs with its legs attached, so the weight associated with robotic technology is improving. Valkyrie also requires a lot less electrical power than R2 and far fewer chips.

Current materials science, battery technology, and computer technology aim to reduce those weights and expand the capabilities of the robots by adding many more sensors and degrees of freedom for mobility, such that the robot moves like humans move. Very recently, polymer fibers that expand and contract like muscles were created.

A Micro-Muscular Break Through

Using Consumer Electronics in Space

The consumer electronics aboard ISS are routinely replaced with new units because the radiation environment of space is not kind to electronics. As a function of distance and launch opportunity, this is much more difficult to do when you're in a base on Mars vs in a space station circling around the Earth and the radiation will damage the electronics whether they're on or off.

Battery Technology

If you bring one lead-acid battery, it would weigh as much as all the 3D printer related stuff I want to bring, except for the robot. I seriously doubt anyone would bring lead-acid batteries to Mars, though. Lithium-ion batteries exceed the capabilities of Lead-acid batteries in every respect (weight, energy density, power density, cycle life, operating temperature range, and even cost if cycle life and weight are considered). When graphene batteries become available as commercial products, we'll use graphene for the exact same reasons we'd use Lithium-ion instead of Lead-acid.

Dook wrote:

A 3D printer and powder represents and entire parts warehouse? Which of the above things can a 3D printer make?

This was previously asked and answered.

Dook wrote:

The real issue is not weight of powder vs the weight of the part already made. They're exactly the same weight. As for size the powder actually takes up a bit more space because it's not compacted and full of air molecules. The issue is that you "think" the powder is lighter in weight than the pre-made object.

No, the issue is that you can't take spare parts for every single thing that could possibly break, or you will easily exceed the weight of the 3D printer and print media. Taking a single circuit board is not a big deal at all, but taking hundreds of boards creates a packaging problem. If you design the electronics in such a way that you basically have electronics inked onto credit card sized "modules", then you essentially eliminate the requirement to transport and manufacture inventories of specialized electronics.

We can basically use ink combinations of varying resistivity to create electronic circuits. The inked "electronic components" will be extraordinarily rad-hard compared to the chips, the actual circuitry is about as heavy as scotch tape (excluding the plastic credit cards they're printed onto), and it's very easy to "upgrade" by peeling the old electronic tape off the credit cards and printing new electronic tape onto the same credit cards. All of the cards would be plugged into a backplane board to create the computer, kinda like computers from the 1970's.

3D-printed microelectronics for integrated circuitry and passive wireless sensors

Dook · 2017-05-06 16:10:56

kbd512 wrote:

Dook wrote:
The issue isn't the weight of the powder vs the part but the combined weight of all the parts that don't get used? Why wouldn't a new filter get used? Or new bearings? New acid plates for batteries? New o-rings for the accumulators? New electric motors? New vacuum pumps? New fan motors? New P sensors? Why wouldn't a new motherboard or hard drive get used? Are you saying those things will somehow last forever on Mars?
Component and System Operating Life
Nothing is going to last forever on Mars. Some things will last a lot longer than others. Seals and bearings are good examples of things that typically last a long time and don't weigh very much, so it'd be a good idea to take replacement parts manufactured on Earth. A printer could actually recondition the seals with less media mass and negate the need to bring multiple replacements, but let's go with the assumption that whatever is light and therefore cheap to bring should be brought. There haven't been many seals or bearings replaced aboard ISS and the temperature extremes and cycle frequency are even greater than on Mars, but ISS is not subject to the abrasive dust in the Martian atmosphere.
3D Printing Technology
3D printers of the sort I envision are light, therefore cheap to bring, and should be brought. The media will weigh more than the print heads by a substantial margin.
Robotics Technology
We're going to bring DARPA / NASA / General Motor's Robonaut 2 or R2 or probably NASA's new Valkyrie by the time we're actually ready to go to Mars. R2 is aboard ISS right now. Robots like R2 can handle tasks that are dangerous for humans to do or require extreme precision to accomplish. Space walks and 3D printing are good examples. The tasks R2 performs aboard ISS include manipulation of avionics and electronics, assembly / disassembly of equipment like avionics and life support systems using hand tools, interfacing with computer systems to run diagnostics, communicating problems to humans and mission control, and eventually space walks (requires thermal management upgrades to the chassis. More than two decades of development and testing are incorporated into this family of technologies.
Robonaut R2 Homepage
Robonaut 2 NASAfacts
Robonaut 2 NASAfacts Updates
R2 was designed by GM and NASA as a modular family of systems to perform tasks in space to assist humans. When R2 is attached to Centaur 2, R2 performs the same tasks your Marscat performs. Centaur 2 contains four 9.9kW electric motors and an adjustable center of gravity. Apart from the upper half of R2, Centaur 2 also mounts a removable bucket, dozer blade, or drill on the other end. When R2 is attached to Spider, which as the name suggests is a robotic lower appendage for R2 that has 8 legs and moves like a spider, to move across terrain that would be impassable for a wheeled vehicle like Centaur 2. In any event, we already have a robot to attach the print heads to.
Robonaut 2 weighs 490lbs with its legs attached. I think Centaur 2 is around 1,500lbs. Both can be tele-operated using VR or autonomously operated, combined (R2 torso attached to Centaur 2) or separate (Centaur 2 does its own thing). Valkyrie is only 300lbs with its legs attached, so the weight associated with robotic technology is improving. Valkyrie also requires a lot less electrical power than R2 and far fewer chips.
Current materials science, battery technology, and computer technology aim to reduce those weights and expand the capabilities of the robots by adding many more sensors and degrees of freedom for mobility, such that the robot moves like humans move. Very recently, polymer fibers that expand and contract like muscles were created.
A Micro-Muscular Break Through
Using Consumer Electronics in Space
The consumer electronics aboard ISS are routinely replaced with new units because the radiation environment of space is not kind to electronics. As a function of distance and launch opportunity, this is much more difficult to do when you're in a base on Mars vs in a space station circling around the Earth and the radiation will damage the electronics whether they're on or off.
Battery Technology
If you bring one lead-acid battery, it would weigh as much as all the 3D printer related stuff I want to bring, except for the robot. I seriously doubt anyone would bring lead-acid batteries to Mars, though. Lithium-ion batteries exceed the capabilities of Lead-acid batteries in every respect (weight, energy density, power density, cycle life, operating temperature range, and even cost if cycle life and weight are considered). When graphene batteries become available as commercial products, we'll use graphene for the exact same reasons we'd use Lithium-ion instead of Lead-acid.
Dook wrote:
A 3D printer and powder represents and entire parts warehouse? Which of the above things can a 3D printer make?
This was previously asked and answered.
Dook wrote:
The real issue is not weight of powder vs the weight of the part already made. They're exactly the same weight. As for size the powder actually takes up a bit more space because it's not compacted and full of air molecules. The issue is that you "think" the powder is lighter in weight than the pre-made object.
No, the issue is that you can't take spare parts for every single thing that could possibly break, or you will easily exceed the weight of the 3D printer and print media. Taking a single circuit board is not a big deal at all, but taking hundreds of boards creates a packaging problem. If you design the electronics in such a way that you basically have electronics inked onto credit card sized "modules", then you essentially eliminate the requirement to transport and manufacture inventories of specialized electronics.
We can basically use ink combinations of varying resistivity to create electronic circuits. The inked "electronic components" will be extraordinarily rad-hard compared to the chips, the actual circuitry is about as heavy as scotch tape (excluding the plastic credit cards they're printed onto), and it's very easy to "upgrade" by peeling the old electronic tape off the credit cards and printing new electronic tape onto the same credit cards. All of the cards would be plugged into a backplane board to create the computer, kinda like computers from the 1970's.
3D-printed microelectronics for integrated circuitry and passive wireless sensors

A 3D printer could recondition seals? Seals weigh almost nothing. One 3D printer and it's powder will weigh more than a two hundred year supply of seals for every piece of equipment on Mars.

So, you think you can't take spare parts for life support systems but you can take multiple 3D printers and hundreds of pounds of powder even though the 3D printers can't make any of the high failure items that operate the life support?

To repair two Moxies we would need: two P sensors, two cryocoolers, two dust imagers, two vacuum pumps, ten accumulator o-ring sets, and two electronics boxes. All of that would weigh about 65 lbs total.

To repair the WAVAR we would need: one small motor, one magnetron, one wave guide, one electronics box. Those things would weigh about 20 lbs total.

So, with 85 lbs of parts I can repair two Moxies and one WAVAR unit. How much would your 3D printer and powder weigh and how many Moxies and WAVAR units can it fix?

Basically, you've put making shelf brackets on Mars as a higher priority than having backup components for life support systems that provide oxygen, water, and food.

Why is having a very small production ability on Mars so incredibly important to all of you even though it can't repair life support equipment? Are you under the impression that if they just have a 3D printer that they can somehow expand the base quicker and make all kinds of stuff?

Is the ISS using it's 3D printer to print new modules or solar panels? Nope. Hmm, I wonder why.

Lithium-ion batteries exceed lead-acid batteries? And they set themselves on fire too.

Taking hundreds of circuit boards would be a problem? Who said there was hundreds of circuit boards needed? The Moxie has an electronics box probably about the size of a normal computer. The WAVAR is probably the same.

What are you going to spray the silver onto, a fiberglass board, right? That fiberglass board has to be shipped from the Earth. You think you're saving rocket fuel by shipping the disassembled parts from the Earth and assembling them on Mars.

How many spare parts are you going to take for the 3D printer?

kbd512 · 2017-05-06 19:15:03

Dook,

One 3D print head to make electronics weighs less than a pound and a metal print head would weigh several pounds. The graphene-based conductive inks are literally some of the lightest materials in the world. Why do you think hundreds of pounds of powders are required to do anything useful with a printer? We're repairing or replacing electronics and small metal parts that go bad, threaded aluminum blocks that have their threads stripped, and reinforcing cracked or punctured pressure vessels. Hundreds of pounds of powder are not required to do any of that.

Aerospace manufacturers don't use 3D printers to make brackets, so this repeated nonsense about only being able to manufacture shelf brackets is provably false. Try a new argument that has some kind of validity.

What the hell is a "dust imager"? MOXIE doesn't "image" any "dust". It filters out dust. Do you mean a "dust filter"?

You said your Marscat would have two 30hp electric motors powered by Lead-acid batteries. Let's do some more basic math to show why your insistence on Lead-acid batteries weighs more than my 3D printing solution.

60hp is 44.75kW. An Interstate 12V battery stores 75AH and weighs 51.8lbs. That's 900Wh of electrical power storage. To run the Marscat for 1 hour, let's optimistically assume we only need 22kWh worth of electricity. That means 24 lead acid batteries are required to run the Marscat for slightly less than 1 hour.

22,000Wh / 900Wh = 24.4 75AH Lead-acid batteries

24 batteries * 51.8lbs = 1,243.2lbs of Lead-acid batteries

Interstate SLA1175

For comparison purposes, a SmartBattery 12V 260AH Lithium-ion battery weighs 80lbs. That's 3,120Wh of electrical power storage.

22,000Wh / 3,120Wh = 7.05

80lbs * 7 batteries = 560lbs

Smart Battery 12V 260AH Lithium Ion Battery

Those figures are for commercial products that anybody with money can purchase. Apples to apples, a SmartBattery 12V 75AH Lithium-ion battery weighs 25lbs and an Interstate 12V 75AH Lead-acid battery weighs 51.8lbs.

Here on Earth because there is oxygen in Earth's atmosphere and Lithium reacts with Oxygen when a cell ruptures. There is no significant amount of oxygen in the atmosphere on Mars. Mars seal level is equivalent to Earth's atmosphere at about 130,000ft. We use CO2 to extinguish electrical fires.

The Lithium-ion batteries are also capable of many more cycles than the Lead-acid batteries and have better cold temperature performance, just in case you needed to run the Marscat for more than a few months before the batteries quit working. With the 683lbs I saved by using batteries that would actually last 2 years in an environment like the surface of Mars, I can afford to deliver the print heads, the inks or powders, and the robot.

SpaceNut · 2017-05-06 19:52:43

RobertDyck wrote:

And so it continues: Dook vs The Mars Society

I see the saga still is in full color 3D mode

Dook wrote:

Could they bring them home and end the mission entirely? Yes. That would absolutely happen if settlers are not able to produce enough oxygen, food, and water, or if any of the crew died.
This is why I am so against inefficiency and trying to collect regolith or ice on Mars and trying to ship everything like forges, 3D printers that don't provide life support. Those things increase the risk of mission failure. The mission is survival, not the production of metal shelf brackets.

But with the aid of them we are able to build things that we will not need to ship on the next mission cycle and can make sure we have other things that we do need.

Dook wrote:

When have humans ever stopped exploring? What day did that happen?

When we started going around in circles in LEO....

3D printers:
The Free Beginner’s Guide

https://all3dp.com/best-3d-printer-fila … ood-metal/

Types of 3D Printing Materials

or

What materials do 3D Printers use?

https://blog.tinkercad.com/materialsguide/

https://www.shapeways.com/materials

3D Printing Materials: The Pros and Cons of Each Type

Yes they now are capable of rubber goods as well:

3D Printed Rubber Products

The strongest and highest temperature thermoplastics with quality finish

https://ninjatek.com/products/filaments/ninjaflex/

http://www.stratasys.com/materials/polyjet/rubber-like

https://www.llnl.gov/news/3d-printed-fo … -materials

Dook · 2017-05-06 20:09:50

kbd512 wrote:

Dook,
One 3D print head to make electronics weighs less than a pound and a metal print head would weigh several pounds. The graphene-based conductive inks are literally some of the lightest materials in the world. Why do you think hundreds of pounds of powders are required to do anything useful with a printer? We're repairing or replacing electronics and small metal parts that go bad, threaded aluminum blocks that have their threads stripped, and reinforcing cracked or punctured pressure vessels. Hundreds of pounds of powder are not required to do any of that.
Aerospace manufacturers don't use 3D printers to make brackets, so this repeated nonsense about only being able to manufacture shelf brackets is provably false. Try a new argument that has some kind of validity.
What the hell is a "dust imager"? MOXIE doesn't "image" any "dust". It filters out dust. Do you mean a "dust filter"?
You said your Marscat would have two 30hp electric motors powered by Lead-acid batteries. Let's do some more basic math to show why your insistence on Lead-acid batteries weighs more than my 3D printing solution.
60hp is 44.75kW. An Interstate 12V battery stores 75AH and weighs 51.8lbs. That's 900Wh of electrical power storage. To run the Marscat for 1 hour, let's optimistically assume we only need 22kWh worth of electricity. That means 24 lead acid batteries are required to run the Marscat for slightly less than 1 hour.
22,000Wh / 900Wh = 24.4 75AH Lead-acid batteries
24 batteries * 51.8lbs = 1,243.2lbs of Lead-acid batteries
Interstate SLA1175
For comparison purposes, a SmartBattery 12V 260AH Lithium-ion battery weighs 80lbs. That's 3,120Wh of electrical power storage.
22,000Wh / 3,120Wh = 7.05
80lbs * 7 batteries = 560lbs
Smart Battery 12V 260AH Lithium Ion Battery
Those figures are for commercial products that anybody with money can purchase. Apples to apples, a SmartBattery 12V 75AH Lithium-ion battery weighs 25lbs and an Interstate 12V 75AH Lead-acid battery weighs 51.8lbs.
Here on Earth because there is oxygen in Earth's atmosphere and Lithium reacts with Oxygen when a cell ruptures. There is no significant amount of oxygen in the atmosphere on Mars. Mars seal level is equivalent to Earth's atmosphere at about 130,000ft. We use CO2 to extinguish electrical fires.
The Lithium-ion batteries are also capable of many more cycles than the Lead-acid batteries and have better cold temperature performance, just in case you needed to run the Marscat for more than a few months before the batteries quit working. With the 683lbs I saved by using batteries that would actually last 2 years in an environment like the surface of Mars, I can afford to deliver the print heads, the inks or powders, and the robot.

Why do I think hundreds of pounds of powders are required? If you want to print metal components, not just circuits, then you need metal powder, not just conductive ink. You've said you would take multiple 3D printers. Plus, you've stated that we could print seals, so you need synthetic rubber and plastic.

Aerospace manufacturers don't use 3D printers to make brackets? So 3D printers can't even make brackets?

What the hell is a dust imager? Don't know, but there's one in the Moxie. Engineers always over-design things.

I would need 24 lead acid batteries to run the Marscat for one hour? No, I wouldn't. Deep cycle batteries have 900 cold cranking amps at 12 volts (Watts = Amps x Volts), so that is 10,800 watt hours, not 900 watt hours. I think eight to ten batteries would provide one or two hours a day of use and then they would be recharged. We don't want to run them down too much.

Lithium-ion batteries store more energy than lead-acid, there's no doubt about it, but they short out too often and catch fire. We can't have that on a spacecraft. Now, the lithium-ion batteries for the Marscat could possibly be assembled on Mars so there's no risk to the spacecraft in flight.

The lead-acid batteries for the Marscat and Long Range Rover could have the batteries empty of water and then add the water on Mars. That might provide more safety from any kind of short happening in any of those batteries from launch vibration or aero-capture.

Dook · 2017-05-06 20:18:09

SpaceNut wrote:

RobertDyck wrote:
And so it continues: Dook vs The Mars Society
I see the saga still is in full color 3D mode

Dook wrote:
Could they bring them home and end the mission entirely? Yes. That would absolutely happen if settlers are not able to produce enough oxygen, food, and water, or if any of the crew died.
This is why I am so against inefficiency and trying to collect regolith or ice on Mars and trying to ship everything like forges, 3D printers that don't provide life support. Those things increase the risk of mission failure. The mission is survival, not the production of metal shelf brackets.
But with the aid of them we are able to build things that we will not need to ship on the next mission cycle and can make sure we have other things that we do need.
Dook wrote:
When have humans ever stopped exploring? What day did that happen?
When we started going around in circles in LEO....

3D printers:
The Free Beginner’s Guide
https://all3dp.com/best-3d-printer-fila … ood-metal/
Types of 3D Printing Materials
or
What materials do 3D Printers use?
https://blog.tinkercad.com/materialsguide/
https://www.shapeways.com/materials
3D Printing Materials: The Pros and Cons of Each Type

Yes they now are capable of rubber goods as well:
3D Printed Rubber Products
The strongest and highest temperature thermoplastics with quality finish

https://ninjatek.com/products/filaments/ninjaflex/
http://www.stratasys.com/materials/polyjet/rubber-like
https://www.llnl.gov/news/3d-printed-fo … -materials

With the aid of 3D printers we are able to build things that we will not need to ship on the next mission cycle? 3D printers cannot make 95% of the life support equipment components. Also, the powder that has to be shipped from the Earth for the 3D printer weighs exactly the same as shipping the component already made.

So, if a 3D printer won't make any life support components then the only thing you can use it for is to make things that will not allow your settlement to grow. Growth is controlled by oxygen, water, food, and then shelter.

We started going around in circles in LEO? Yeah, the space shuttle was fine at first but we stuck with it for too long. Still, we have launched probes to other planets and rovers to Mars and Hubble and James Webb.

Can someone please give me a list of all the important things you would use a 3D printer to make on Mars?

Last edited by Dook (2017-05-06 20:18:41)

SpaceNut · 2017-05-06 21:07:11

What are the items that a " 3D printers cannot make 95% for life support equipment components. " that we can not make that will fail in less than 3 mars launch cycles? As that is how long it could take to get what you need to fix you equipment or to replace it.

Dook · 2017-05-06 21:28:28

SpaceNut wrote:

What are the items that a " 3D printers cannot make 95% for life support equipment components. " that we can not make that will fail in less than 3 mars launch cycles? As that is how long it could take to get what you need to fix you equipment or to replace it.

The most likely failure parts of a Moxie are: P sensor, dust imager, cryocooler, electronics box, vacuum pump, CO2 condenser, the SOXE, and O2 accumulator.

A 3D printer could make some electronic chips, the impeller blades for a vacuum pump and it's housing but not it's bearings or electric motor.

The most likely failure parts of a WAVAR are: electric motor, two magnetrons, two wave guides, rack and pinion, and the electronics box.

A 3D printer could make some electronic chips and short sections of iron that would have to be cut to provide a new rack and pinion section if it failed.

I don't know the CAMRAS so I can't go into it.

Will the life support fail in less than 3 Mars launch cycles? I doubt it but what if the Moxie does fail, can you hold your breath for 3 Mars launch cycles?

Last edited by Dook (2017-05-06 21:28:57)

SpaceNut · 2017-05-06 21:33:20

Ok and thank you, now off to research these and will reply tomorrow if time allows... good night....still fixing my earthly rover...as its inspection did not pass....Did front rotors/pads and back drums /shoes braking systems but still other things to clear in order to pass....

Dook · 2017-05-06 21:54:15

Okay, I looked at the CAMRAS and, near as I can tell, these are the main components:

Aluminum body
Dessicant wheel and small motor
Porous plastic beads coated with an amine
Two temperature sensors
Blower
Vacuum jumper hose
Absorbing bed
Desorbing bed
Seals
Air save tank
Electronics box

I don't believe the small 3D printer that makes electronics can make larger solid metal components. I could be wrong, but the small electronics one just sprays hot silver, whereas a 3D printer that spray metal powder uses a laser to melt the powder.

So, of the above CAMRAS components, a 3D printer for spraying hot silver for making electronics and another 3D printer with a laser for spraying metal can make some of the pieces of a blower, a vacuum hose, it might make seals if they are rubber seals, not if they are compression fibrous material seals, electric motor case, and it would make some electronics.

Last edited by Dook (2017-05-06 21:59:09)

RobertDyck · 2017-05-06 22:05:01

Apollo 11 landed on the Moon: July 20, 1969
Apollo 17 splashed down: December 19, 1972

That's how quick it was cancelled. Apollo used all expendable equipment.

Shuttle first launch: April 12, 1981
Shuttle last flight: July 21, 2011

It flew for 30 years. That's what you get with reusable equipment. Robert Zubrin wants a Mars mission with entirely expendable equipment. I argue for the interplanetary vehicle to be reusable. This is one reason why.

Skylab launch: May 14, 1973
Skylab first human mission, launch: May 25, 1973
Skylab last human mission, splashdown: February 8, 1974
Skylab uncontrolled deorbit and crash: July 11, 1979

Skylab was required crew to operate it. It had food, oxygen, water, and lithium hydroxide canisters to scrub CO2 for many more days than it was occupied. The 4th crew mission to Skylab was cancelled. This is what happens when you need constant resupply. And Skylab only required crew, it had on-board supplies for many more missions.

Last edited by RobertDyck (2017-05-06 22:08:57)

kbd512 · 2017-05-06 22:44:44

Dook wrote:

Why do I think hundreds of pounds of powders are required? If you want to print metal components, not just circuits, then you need metal powder, not just conductive ink. You've said you would take multiple 3D printers. Plus, you've stated that we could print seals, so you need synthetic rubber and plastic.

Do you need more or less material to resurface a piece of rubber?

Dook wrote:

Aerospace manufacturers don't use 3D printers to make brackets? So 3D printers can't even make brackets?

So you're still stuck on this bracket nonsense?

Dook wrote:

What the hell is a dust imager? Don't know, but there's one in the Moxie. Engineers always over-design things.

The engineers probably want to know how fast the dust degrades MOXIE by measuring the particulate sizes ingested. That way, they don't have to "over-design" a piece of production equipment. I don't have a "fly imager" in front of the radiator on my car, since the engineers determined about a century ago that the flies wouldn't hurt the radiator. It's a safe bet that a test apparatus from a science experiment has little to do with a piece of production hardware. The good news is that you won't need spare test equipment from a science experiment.

Dook wrote:

I would need 24 lead acid batteries to run the Marscat for one hour? No, I wouldn't. Deep cycle batteries have 900 cold cranking amps at 12 volts (Watts = Amps x Volts), so that is 10,800 watt hours, not 900 watt hours. I think eight to ten batteries would provide one or two hours a day of use and then they would be recharged. We don't want to run them down too much.

Battery capacity is measured in amp-hours, or "AH". If the capacity of a 12 volt battery is 75 amp-hours (75AH), then that means it can deliver a maximum of 75 amps of current for one hour at a voltage of 12 volts. You get less than that in real life, but I'm trying to keep this simple.

Cranking amps are a marketing tool used to tell people how fast their battery can discharge without using confusing them with terms like energy density (how many watts of power the battery can store for a given volume and mass) and power density (how many watts of power the battery can deliver in a given unit of time).

The "900 cold cranking amps" in your example means the battery can deliver a maximum of 10.8kW of electrical power to an electric starter motor (1hp = 745.7W, so 14.48hp, assuming 100% conversion efficiency), but if you try to discharge a 75AH Lead-acid battery that fast it'll be completely discharged in 5 minutes.

60 seconds * 60 minutes per hour = 3,600 seconds per hour

10,800 watt-hours divided by 3,600 seconds per hour = 3 watts per second

3 watts per second * 60 seconds = 180 watts per minute

180 watts per minute * 60 minutes = 10,800 watts per hour

P (power in watts) = I (current flow measured in terms of amperes or amps) * V (electrical potential difference measured in terms of volts)

900 (watt-hours) = 75 (amp-hours) * 12 volts

900 watts / 180 watts per minute = 5 minutes at a discharge rate of 10,800 watts per hour (900 cranking amps at 12 volts)

5 minutes is the maximum length of time any 12 volt 75AH battery (irrespective of what type it is, Lead-acid, Lithium-ion, Nickel Metal Hydride, Graphene, etc) would deliver current at a rate of 10.8kW per hour. Like I said previously, it's less than that in real life if you don't want to destroy the battery. Going past 80 DoD (Depth-of-Discharge) is typically not conducive to long battery life.

Peukert's Law also affects battery capacity as a function of discharge rate.

t = H(C / (IH))^k

t [time] = H [hours] ( C [capacity in amp-hours] / (I [current in amps] * H [hours]))^k [Peukert's exponent; differs for every battery]

The equation shown above does not account for temperature, number of cycles already completed (causes the Peukert exponent to increase), or self-discharge. This is just extra stuff for you to use to figure out exactly how long a battery can be discharged. You'll need to get the Peukert exponent from the manufacturer. If you get this information, then you can get a reasonably good idea of how the battery will actually perform. Temperature is also critical. Battery capacity diminishes in cold temperatures and increases in warmer temperatures up to a certain point.

Now that you know how to correctly calculate battery capacity, do you still want to use Lead-acid?

Dook wrote:

Lithium-ion batteries store more energy than lead-acid, there's no doubt about it, but they short out too often and catch fire. We can't have that on a spacecraft. Now, the lithium-ion batteries for the Marscat could possibly be assembled on Mars so there's no risk to the spacecraft in flight.

ISS uses lots of Lithium-ion batteries and there have been no fires aboard ISS from Lithium-ion batteries.

Dook wrote:

The lead-acid batteries for the Marscat and Long Range Rover could have the batteries empty of water and then add the water on Mars. That might provide more safety from any kind of short happening in any of those batteries from launch vibration or aero-capture.

Properly designed Lead-acid batteries won't short, either.

kbd512 · 2017-05-07 00:37:00

Dook wrote:

Okay, I looked at the CAMRAS and, near as I can tell, these are the main components:
Aluminum body
Dessicant wheel and small motor
Porous plastic beads coated with an amine
Two temperature sensors
Blower
Vacuum jumper hose
Absorbing bed
Desorbing bed
Seals
Air save tank
Electronics box
I don't believe the small 3D printer that makes electronics can make larger solid metal components. I could be wrong, but the small electronics one just sprays hot silver, whereas a 3D printer that spray metal powder uses a laser to melt the powder.
So, of the above CAMRAS components, a 3D printer for spraying hot silver for making electronics and another 3D printer with a laser for spraying metal can make some of the pieces of a blower, a vacuum hose, it might make seals if they are rubber seals, not if they are compression fibrous material seals, electric motor case, and it would make some electronics.

I am by no means suggesting that we don't take backup MOXIE, CAMRAS, or IWP units. I think triple redundant life support systems should be standard for any extended mission duration spacecraft, but that means 3 complete units. If more than 3 complete life support systems are required in a span of two years, then there are serious design issues to address and that should probably be done before the exploration phase begins. If you have to take an entire hardware store to Mars to ensure that whatever needs to be repaired gets repaired, then something is wrong with the basic design.

We already know how things fail and can even predict when things will fail from testing. I'm trying to account for stupid human mistakes (wrong parts sent; if you have different versions of the same equipment then the likelihood of this happening increases, replacement part still fails because of defective design, human accidentally broke a working unit doing something stupid during maintenance or operation) by sending 3D printers, not rebuilding entire pieces of life support equipment from scratch.

If a human damages a circuit board, a printer can repair the existing circuit board. If a circuit board was 3D printed to begin with, then another printer can literally unsolder and re-solder components on the board. Voxel's technology takes account of the fact that humans make mistakes.

If a human strips a thread on a screw hole, a printer can fill it in. The requirement for a second head to drill and re-thread the hole does not mean a gigantic drill press. After the filling in the hole with a metal print head, switch the tool to a drill, drill the hole, switch the tool to a tap, and then thread the hole. The colonists need tools to begin with and Robonaut was designed to use human hand tools. The difference is that humans aren't capable of repeatable movements requiring sub-millimeter precision or working outside 24/7 without food, water, or oxygen. Humans get tired, hot, cold, hungry, and thirsty. The robot never does.

If a human drops and breaks an aluminum plate of the kind that electronics, MOXIE, CAMRAS, and IWP use as chassis material, then the printer can weld the plates back together or repair the chip taken out of the plate with very little in the way of fixturing. There are a limited number of alloys typical to spacecraft electronics and life support equipment design and since we already have the engineering design specs for all the systems, we can probably remember to send the right kinds of powdered metals and screws or nuts and bolts.

We need 1 print head for circuitry, 1 print head for metals, 1 print head for plastics, and 1 print head for rubbers or sealants. The metal print head will be heavier and require more power than the rest. Volumetrically, the print heads are about the size of large screw driver handles. We'd have 1 print enclosure with XYZ axis servos for stationary printing (broken things inside the pressurized module) and 1 robot for mobile printing applications (broken things outside the pressurized module).

RobertDyck · 2017-05-07 03:24:16

What's up with this obsession about 3D printers? They're a tool. All tools are useful but have limits. Don't try to do everything with the same tool.

kbd512 wrote:

If a human damages a circuit board, a printer can repair the existing circuit board. If a circuit board was 3D printed to begin with, then another printer can literally unsolder and re-solder components on the board. Voxel's technology takes account of the fact that humans make mistakes.

You want to unsolder work done by a human, and do it over again by machine? What? That's backwards. The machine makes mistakes. A human has to check quality, and if the machine made a mistake the human fixes it. This sounds like you assume all humans are incompetent.

kbd512 wrote:

If a human strips a thread on a screw hole, a printer can fill it in.

Again, why the printer? Are you assuming crew don't have any skill? If a human strips a thread, a human can use an arc welder to fill the hole. Then either a drill press, or just a drill stand for a hand drill. Someone with skill can drill a vertical hole with a hand drill alone, no stand. Then use a hand tool called a tap to cut threads. The most complicated tool is the arc welder.

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