Blender Collaboration Large Ship Habitat Ring

tahanson43206 · 2022-08-15 12:57:33

There are three versions of "Large Ship" active in August of 2022.

The first is the original hammerhead shaped design created by RobertDyck, and developed over two years and counting.

The second is a dual-counter-rotating-habitat design under development by kbd512.

The third is a combination of the two, which I will attempt to develop.

All three have in common, a habitat ring where passengers and crew will spend most of their time.

RobertDyck has created models of the original hammerhead design in Blender, and posted images in the original Large Ship topic

This topic is designed to work with the NewMars Dropbox account.

My hope is that all three designers will collaborate in creating models of the Habitat Ring, suitable for 3D Printing at 1:1000 scale.

The original Large Ship Habitat Ring was specified as having a radius of (about) 37 meters, for a diameter of (about) 75 meters.

The width is specified as exactly 19 meters.

Other details of the original design may be found in the Large Ship topic.

My intention is to add them here as they are brought to my attention.

A 1:1000 scale model would be 75 millimeters in diameter, which is well within the capability of an ordinary home 3D Printer.

A typical low end 3D Printer has a print stage 200 millimeters on a side.

(th)

tahanson43206 · 2022-08-22 18:02:54

As planned, I have set up a shared folder in DropBox for models of the Large Ship Habitat ring.

I am making the assumption the same habitat ring will be acceptable to all three designers:

RobertDyck - Large Ship Unitary Rotation - originator of habitat specifications

kbd512 - Large Ship Counter Rotating habitats with a common axis of rotation

tahanson43206 - Large ship Counter Rotating habitats with parallel axles as designed by Dr. Cortel (( Adolf Cortel 2009) Double gyroscope. ))

All three of the folks listed should have update/edit privileges to the new folders.

My hope is that designs will be shared between the participants, improved as they are inspired, and stored with new names next to the originals.

(th)

tahanson43206 · 2022-08-25 07:37:00

This post is about maintaining stability of the rotating habitat ring as residents go about their daily activities.

Since nothing on this scale has been constructed, let alone put into service in space, it is pure speculation to imagine that the stability of the structure would not be impacted by movements inside the rotating mass. In contrast, we have thousands of years of human experience, and hundreds of years of technology development that confirm the wisdom of avoiding imbalance of rotating devices.

This post is ** specifically ** about a mechanism to provide a mass doppelganger for each resident, on the opposite side of the habitat.

Assuming the residence population is 250, as suggested by kbd512 in his alternate version of Large Ship....

and assuming the width of 19 meters as specified by RobertDyck for the width of the original Large Ship habitat ...

and assuming a width for each doppelganger track of 1 meter, then there would be 18 tracks across the width of the exterior of the ring's outer wall, and a population of 252 persons, then 14 layers would be required to provide a doppelganger for each resident.

While the population grows from zero to 250, unused doppelgangers would be parked in pairs on opposite sides of the habitat ring, distributed so that mass is balanced as the ring rotates.

Clearly the mass of the balance system would deduct from the ship mass budget, so designing for minimal mass for the tracks and control equipment is desirable.

Addendum... it has been suggested by contributors to the various Large Ship topics, that water might be used in a mechanism to deal with mass balance.

It seems reasonable to me to design the doppelganger equipment so that a capability of adjusting the mass by adding or subtracting water would allow the individual device to be fine tuned to the passenger or crew person to be served.

Each human will need to wear a device to broadcast location information to the Ship Control system, so it can move doppelgangers as needed.

(th)

RobertDyck · 2022-08-25 09:26:23

tahanson43206 wrote:

Each human will need to wear a device to broadcast location information to the Ship Control system, so it can move doppelgangers as needed.

Smartphone, with modified version of GPS. The ship will have Wifi, and short-range GPS transmitters that function within the ship.

tahanson43206 · 2022-08-25 11:23:14

For RobertDyck re #4

Thank you for your support of and contribution to this new topic ....

Your recommendation provides an opportunity for an electrical/electronics engineer with an interest in this problem, to contribute a specification for a GPS system that would operate inside a space vessel. While my knowledge of this field is necessarily limited, I have never heard even so much as a hint that anyone might be thinking along these line. On the ** other ** hand, perhaps the cellphone tower location system used by first responders to try to assist cell phone users may provide a direction to look.

It seems to me this would be an interesting technical problem for today's generation of engineering students.

On the third hand, such a system ** may ** already exist. For example, perhaps there is a system designed for use in Amazon (or other) automated warehouses to insure that the location of each piece of automated equipment is known with precision at all times.

If someone not already enrolled in the forum would care to add to this discussion, please check the Recruiting topic for procedure.

(th)

RobertDyck · 2022-08-25 12:09:17

My understanding is GPS satellites transmit a signal with a time code. To work with sub-meter precision, the time code must be so precise it has to be adjusted for time dilation due to orbital altitude in Earth's gravity well. Exact position of the satellite is encoded in the signal, as well as time it was transmitted. The GPS receiver records the exact time it was received. The difference in the two time stamps is the length of time for the signal to travel from the satellite to the receiver. Radio signals travel at the speed of light, so that gives distance from satellite to receiver. Doing this with at least 3 satellites then gives range from 3 known points. The distance can be represented as a sphere surrounding the satellite. Position of the receiver is the intersection of these spheres. To increase accuracy of the distance measurement, modern receivers record the signal not only to a wave of radio signal, but record the phase of the wave. That allows measurement to less than a wavelength of the radio signal.

From NIST: Time and Frequency from A to Z, G

Global Positioning System (GPS)
A constellation of satellites controlled and operated by the United States Department of Defense (USDOD). The constellation includes at least 24 satellites that orbit the Earth at a height of 20,200 km in six fixed planes inclined 55° from the equator. The orbital period is 11 h 58 m, which means that a satellite will orbit the earth twice per day. By processing signals received from the satellites, a GPS receiver can determine its own position with an uncertainty of less than 10 m.
All GPS satellites broadcast on at least two carrier frequencies: L1, at 1575.42 MHz, and L2, at 1227.6 MHz (newer satellites also broadcast on L5 at 1176 MHz). Each satellite broadcasts a spread-spectrum waveform, called a pseudo-random noise (PRN) code on L1 and L2, and each satellite is identified by the PRN code it transmits. There are two types of PRN codes. The first type is a coarse acquisition (C/A) code with a chip rate of 1023 chips per millisecond. The second type is a precision (P) code with a chip rate of 10230 chips per millisecond. The C/A code is broadcast on L1, and the P code is broadcast on both L1 and L2. GPS reception is line-of-sight, which means that the antenna must have a clear view of the sky. The signals can be received nearly anywhere on Earth where a clear sky view is available.

Wavelength is C / F, where C is speed of light, and F is frequency. Speed of light is 299792458 metres per second.
Using L1 frequency: 299792458 / 1575420000 = 0.190294 metres. So measuring distance precisely to one wavelength gives a distance of ±19 cm. Measuring phase allows even more precision.

Time measurement must be very precise. To measure to a single wavelength, the time must be measured to ± 1 / F seconds. Using L1 frequency, that's ±0.634751 nanoseconds.

Could this be done with small transmitters positioned in the ring around the ship?

Ps. Trying to get cheap by using commercial smartphones with a custom app instead of custom hardware.

tahanson43206 · 2022-09-04 19:58:22

Update during Zoom meeting 2022/09/04 ....

RobertDyck has uploaded a model of Large Ship to the NewMars Dropbox account.

I tried downloading the file to a computer that does NOT have Blender installed, and the operating system decided the file is an html file.

I'll try again tomorrow on a different computer.

kbd512 has agreed to use the habitat design as proposed by RobertDyck, and he confirmed that his ship design is intended to mount the counter rotating habitats on a common axle.

(th)

SpaceNut · 2022-09-04 21:35:40

That means the files extension was set on that machine to open with a browser by default.

tahanson43206 · 2022-09-04 21:45:59

For SpaceNut .... thanks for noting the curious behavior of Windows when presented the download from Dropbox.

Your insight about a default setting certainly makes sense ... I use Windows as little as possible.

Tomorrow I'll try the download on a Linux box, and expect better results.

***
The re-scan of Potholes is underway ... Based upon preliminary results from the first two test runs, it appears the "potholes" reported earlier may not be potholes at all, but instead a consequence of Internet delay combined with the script not handling the delays properly.

***
This note ** should ** go into Housekeeping, but I'll just report that investigation of "seeing" pixels on the screen using Simple OCR is looking more and more feasible.

***
This is the Blender topic, so I'll close with a comment that RobertDyck was kind enough to upload his Large Ship blender model to the Dropbox account. I've been looking for motivation to go back to work on the Large Ship (of which we now have three versions), so this file promises to be a helpful restart opportunity.

(th)

tahanson43206 · 2022-09-05 08:32:06

https://www.dropbox.com/s/z6t9vbomvabem … blend?dl=0

This is an experiment to see if the blender file uploaded by RobertDyck as the starting point for this topic is accessible.

The file ** should ** be available for viewing and downloading.

Works that evolve from this seed should credit the origin.

If all goes to plan, this topic will develop a model for the habitat ring of a family of vessel designs.

To repeat the options one more time:

1) Original hammer head design by RobertDyck - Unitary rotation
2) kbd512 "practical" design features two counter rotating habitats on a common axle
3) tahanson43206 design features two counter rotating habitats on parallel separate axles mounted in a frame

All three designs will (hopefully) employ the same basic habitat ring, although details will vary as the designs evolve.

The intention for this topic is to develop and publish 1:1000 scale models that can be 3D Printed by anyone with a modest 3D printer.

Update at 15:05 local time: Bravo! The model created by RobertDyck is working in Blender in Ubuntu 64 ...

I am confident it will work as well on Windows (64 bits) or Mac.

The version of blender I have is 3.0.1 ... no doubt there have been updates since.

To my knowledge we have no members other than RobertDyck and tahanson43206 able to work with Blender, but that could change.

Blender, like Fusion 360, ** does ** require a reasonably capable graphics card.

The program is free and can be downloaded from blender.org.

I will be happy to (attempt to) answer any questions members may have.

However, where I am ** really ** going with this is to (hopefully) interest younger humans who already know how to use Blender, and would like to work on a difficult, large scale project.

This topic is set up to focus on the habitat ring, which is common to all three Large Ship designs. However, the design of the several versions of Large Ship will take volunteer efforts by many folks who are willing to share their work as we go along.

All work should flow from the model created by RobertDyck, and credit that source.

Eventually, I expect this specification to become a standard for an entire fleet of Large Ships, able to carry a minimum of 500 passengers and crew.

If there is a reader of this forum who is not currently a member, and who would like to contribute to ** this ** topic, read the Recruiting topic for procedure.

(th)

tahanson43206 · 2022-09-05 21:03:03

Update at 22:57 after running more experiments with the Blender file created by RobertDyck as a model of the Unitary Rotation Large ship.

I downloaded Blender 2.79 to Windows 7. That is the latest version that will run on Version 7. I have Windows 10 but only use it for taxes, once a year.

Version 3.2.2 will run on Windows 10.

On the ** other ** hand, Blender 3.0.1 is running on Ubuntu 20.04.

The model would not load for Blender 2.79. I suspect it was created with a later version of Blender.

The model loads up nicely in Blender 3.0.1.

I made an stl file (a kind of linqua franca for 3D models) and will import that to the Windows 7 machine tomorrow.

Blender 2.79 should be able to import the stl file.

If anyone else is interested in working on this project, please jump in.

My immediate objective is to (try to) see the inner structure of the model. At this point I've been happy to see anything at all.

(th)

RobertDyck · 2022-09-06 03:32:08

I have Blender version 2.93.1. The file should work with any version of Blender 2.9. Unfortunately Blender does not have a "save as" option to save with other file types, such as older versions. Microsoft Word and Excel do, but Blender is not a Microsoft product. I can export to various formats. I have exported and uploaded Tiu.stl

tahanson43206 · 2022-09-10 12:09:59

For RobertDyck re #12

Thanks for uploading the stl! I missed your post! I've never set a "follow" on a topic, but am thinking of adding one for this topic.

In the mean time, I was able to make an stl using Blender 3+ on Ubuntu, and when I imported it to the Windows 7 machine, Blender 2.79 was able to import it. I have saved the recovered file as a .blend and would appreciate your opening it on your 2.93 system to see if it is intact.

I'd like to use that as the base version for future development, although at this point, I haven't attempted to take measurements.

During conversion between operating systems and versions of Blender, your original specifications may have been changed.

You ** should ** be able to confirm the numbers by downloading and opening the "recovered" .blend from the Dropbox.

Here is a link:
https://www.dropbox.com/s/46hxoaldbhaz1 … blend?dl=0

For anyone ... (and everyone) ... the link above points to a version of Large Ship that will open in 2.79, for those who are limited by circumstances to that version.

If there is someone in the readership who is interested in working on development of the Large Ship Habitat design, please check the Recruiting topic for details.

(th)

RobertDyck · 2022-09-10 13:28:17

Major problems. The ring is shown as a solid disk. It's not supposed to do that. In my version, the ring is composed as a solid disk but then has a "cut out" that is a smaller disk inside it. The upper deck is also a solid disk, and also has a "cut out" that is smaller. There are 3 cylinders that act as spokes, connecting the central hub to the outer ring. If you look in the "Scene Collection", none of this is there. All that exists is one solid disk.

tahanson43206 · 2022-09-10 13:46:41

For RobertDyck re #14

Thanks for taking a look at the output of the procedure.

The North Houston NSS meeting is in progress, so I'll take a look at the file later.

The key question (from my point of view) is whether the dimensions are preserved.

That is the key.

Everything else can be added back or modified as needed.

Update at 16:53 local time ...

For RobertDyck ... I changed the view from solid to wireframe, and the inner rings and the spokes jump right out.

There may be (I'm hoping) simple adjustments that can be made to the display to provide what you are looking for.

In any case, at ** this ** point, I'm looking for dimensions, so will be attempting to discover those from the "recover" version.

The version you sent out originally is loaded up with advanced features, so that I can't see anything at all (on one machine) and just a solid on the other. I'm trying to help to move the project back to a starting point from which a number of folks can build.

(th)

tahanson43206 · 2022-09-22 11:38:32

For RobertDyck re Model for Display at 25th Anniversary Convention

GW Johnson did ** not ** make a commitment one way or the other, but he ** did ** acknowledge my inquiry.

I asked if he might be willing to arrange for display of a Large Ship model (3D printed) if we can arrange to have one shipped to the convention site.

There may be a display space. Often there are at a sizable convention. The model might even be wired/tied to a wall poster, with a bit of text explaining what it is.

In any case, we have a couple of weeks to try to create a model if you are interested.

I have a suggestion for the view problem.... Since the translated and down-version model seems to have a solid exterior, we ** should ** be able to make that surface transparent, so the rendering will look as you have indicated you'd prefer.

I don't expect to have enough time to try to make a model of kbd512's design, by duplicating your model and arranging the pair on the same axle.

(th)

tahanson43206 · 2022-09-25 17:54:10

In preparation for tonight's Zoom session, I have configured an Ubuntu 22.04 instance on a 64 bit machine where Zoom runs. I installed Blender 3.3, and it showed the Large Ship (recovered) model just fine.

It might even show the original model, but that is something to try later.

(th)

New Mars Forums

Announcement

#1 2022-08-15 12:57:33

Blender Collaboration Large Ship Habitat Ring

#2 2022-08-22 18:02:54

Re: Blender Collaboration Large Ship Habitat Ring

#3 2022-08-25 07:37:00

Re: Blender Collaboration Large Ship Habitat Ring

#4 2022-08-25 09:26:23

Re: Blender Collaboration Large Ship Habitat Ring

#5 2022-08-25 11:23:14

Re: Blender Collaboration Large Ship Habitat Ring

#6 2022-08-25 12:09:17

Re: Blender Collaboration Large Ship Habitat Ring

#7 2022-09-04 19:58:22

Re: Blender Collaboration Large Ship Habitat Ring

#8 2022-09-04 21:35:40

Re: Blender Collaboration Large Ship Habitat Ring

#9 2022-09-04 21:45:59

Re: Blender Collaboration Large Ship Habitat Ring

#10 2022-09-05 08:32:06

Re: Blender Collaboration Large Ship Habitat Ring

#11 2022-09-05 21:03:03

Re: Blender Collaboration Large Ship Habitat Ring

#12 2022-09-06 03:32:08

Re: Blender Collaboration Large Ship Habitat Ring

#13 2022-09-10 12:09:59

Re: Blender Collaboration Large Ship Habitat Ring

#14 2022-09-10 13:28:17

Re: Blender Collaboration Large Ship Habitat Ring

#15 2022-09-10 13:46:41

Re: Blender Collaboration Large Ship Habitat Ring

#16 2022-09-22 11:38:32

Re: Blender Collaboration Large Ship Habitat Ring

#17 2022-09-25 17:54:10

Re: Blender Collaboration Large Ship Habitat Ring

Board footer