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16-Pearl
May 1, 2025
Question

Mathcad Community Challenge May 2025 - Spin Gravity!

  • May 1, 2025
  • 6 replies
  • 4738 views

Stanford_Torus_interior.jpg

 

This month’s challenge is based on spin gravity and emphasizes creativity!


Spin gravity is a method of creating the sense of gravity in a low- or zero- gravity environment using rotational movement. During this circular motion, objects with mass feel a fictitious centrifugal force “pushing” them away from the center. This force can feel like the gravity we experience on Earth.

 

You can either design your own space station / vehicle or choose one (or more) from science fiction books, television shows, movies, video games, or other media. Then create a Mathcad worksheet to calculate the following:

  • Radius of your spinning object.
  • Centrifugal acceleration in both distance units per second squared and g’s (acceleration due to gravity at the earth’s surface). Note that your vehicle / station does not need to be 1g. Less than 1g makes it easier to move. More than 1g would help improve your jump shot on your eventual return to Earth.
  • Angular velocity in radians, degrees, and revolutions per time unit. Don’t spin too fast, or you will make people feel sick!
  • Tangential velocity.

 

Examples from popular media include:

  • Books: Ringworld, Rendezvous with Rama, The Expanse series, The Culture series, The Moon is a Harsh Mistress, and The Forever War.
  • Video games: Halo, Prey, and Kerbal Space Program.
  • Television shows: Babylon 5, The Expanse, and For All Mankind.
  • Film: 2001: A Space Odyssey, Interstellar, The Martian, Elysium, Mission to Mars, and Zeta Gundam.

 

In “real” science, O’Neill Cylinders were proposed by Professor Gerard K. O’Neill in 1974. Maybe you can design your own or a variation.


Note that if you create your worksheet in Mathcad Prime 11, you can use a custom unit system in your worksheet! This can be extremely helpful depending on how big you want your station or vehicle to be.

 

Bonus Advanced Input Controls Challenge

Incorporate Combo Boxes, Sliders, Check Boxes, Radio Buttons, or any other input controls to allow users to change a parameter to see how it affects other calculations.

 

Bonus Graphing Challenge

Use XY Plots, 3D Plots, Contour Plots, or Chart Components to depict the acceleration due to gravity as a function of one or more other parameters for a space station / vehicle.

Have fun with this!

 

Find the Mathcad Community Challenge Guidelines here!

 

6 replies

23-Emerald I
May 11, 2025

I'm a little surprised that we're eleven days into May and there have been no posts!

 

Attached (in Express Prime 4) is a simple discussion of the challenges of spin gravity, disguised as a design for a small space station.:

  • A reminder of NASA's error in Explorer 1  about stability of spinning objects.
  • A calculation of the pressure in a column of fluid and the effects of centrifugal acceleration
  • A reminder that things thrown "in a straight line" in a rotating frame of reference do not travel in a straight line.

Enjoy!  Comment!  Expand!

 

ttokoro
21-Topaz I
21-Topaz I
May 12, 2025
16-Pearl
May 13, 2025

I decided to get in on the fun. Here is my worksheet in Mathcad Prime 11. This is a work in progress. I still need to throw in an optimization and take advantage of custom unit systems, especially for RPMs.

 

18-Opal
May 13, 2025

I adore your gravity / radius sliders and the motion sickness conditionally formatted text box!

16-Pearl
May 17, 2025

I've updated my worksheet to take advantage of a couple Prime 11 enhancements:

  • I am using a custom unit system so that the default unit for frequency is RPM instead of Hertz.
  • I duplicated the text box with conditional formatting to be written in Python in addition to JScript.

 

ttokoro
21-Topaz I
21-Topaz I
May 16, 2025
18-Opal
May 16, 2025

Having the spinning object turn red (even more red than your screenshot) is very fun!

ttokoro
21-Topaz I
21-Topaz I
May 25, 2025
18-Opal
June 9, 2025
18-Opal
June 10, 2025

Well, you're late... but your worksheet is cool, so I'll allow it anyway. 😀

18-Opal
July 10, 2025

Speaking of late, here's the write-up article for Spin Gravity: https://www.mathcad.com/en/blogs/community-challenge-spin-gravity