Hoberman Habitat: Expandable & Efficient Space Living

Reimaging life in space through easily portable and sustainable infrastructure!

Hi everyone! My name is Vedic Patel, and I am an incoming freshman at Northeastern University for mechanical engineering. I’ve always been fascinated by origami (mostly due to a book called “The Strange Case of Origami Yoda”)— folding cranes to dragons since I was six. For this challenge, I wanted to tap into my interest in origami and a specific design: Kusudama’s medicine ball, which uses concepts from Chuck Hoberman’s “Hoberman mechanism.”

My design starts out as a contracted spherical frame with a parachute-like material (Phase 1), consisting of many linkages and joints. Once landed where desired using a large parachute-like system. Then, the large sphere divides into two domes (Phase 2). These domes expand into larger ones (Phase 3) using Hoberman mechanics. As the two domes continue to expand, the parachute-like system gives coverage on each dome's open frame.

I designed my habitat CAD model and animation from scratch using Fusion 360's Student version. For my physical prototype, I used my CAD-ed models and printed on a Creality K1 printer. For assembly, I used screws and other miscellaneous parts. Outside resourced are linked throughout this Instructable.

Brainstorming an Idea

I first researched Aurelia Institute's TESSERAE project, which self-assembles through Spaceflight Tiles. Seeing how these stacked tiles can make a larger shape, I want to explore other options for making larger shapes. I believe a habitat should be easily transportable, but also provide ample space for work and play. With an expanding habitat, I can ignore the constraints a rocket may have in transportation, but have the benefits of a larger living space.

As mentioned before, one of my biggest hobbies is origami, and some of my favorite designs are the ones that can expand and contract. Connecting the research from the TESSERAE project to transformable origami design, I stumbled across the Hoberman sphere and mechanism.

What is a Hoberman Mechanism?

Hoberman mechanisms can most commonly be seen in a popular children’s toy: a Hoberman Sphere. This toy expands from a small sphere to a large one simply through light pulling.

The sphere’s expansion mechanism can be explained by the Hoberman Mechanism, which is made up of small bars/ linkages and joints. These small parts (bars/linkages) are connected at a central joint and creates a scissor-like mechanism. The joints of each part move along a linear axis (translating linear motion in radial motion), so as a result of pulling on one joint, the entire shape expands.

Using the Hoberman Mechanism to Build an Efficient Living Space

After understanding the expansion of a Hoberman sphere, I began to explore other shapes that I can create using Chuck Hoberman's mechanism. I chose a sphere due to the resilience of its shape and the common application of the Hoberman mechanism, however, chose to divide the sphere into halves (domes) to address unused space due to the curvature and awkward need for multi-stairs in a sphere-like design.

• Fusion360 Student Version
• Creality K1 printer
• M2 x 4mm Screws
• Screwdriver
• Miura-ori (Expandable Material)
• (OPTIONAL for pictures) iPhone 13 camera and a Gundam

Since I wanted my design to be easily transportable and support extraterrestrial living, I had to design with space-transportation in mind. I researched sizes of rockets, specifically SpaceX's Starship due to it being a transportation system "designed to carry both crew and cargo to Earth orbit...and beyond." I set the Starship's dimensions (9 meter diameter) as my habitat's max limits with tolerance, settling on my habitat max (when it is a sphere) to be 8 meters in diameter.

After setting the max constraint on my habitat, I went straight to my engineering sketchbook and Fusion 360 to brainstorm and test out designs.

To begin, I first started with a cross-section of a sphere (an 8 meter diameter circle) to act as the frame of my design. I then needed to divide my circle into a smaller parts to work with, so I decided on quarters, as I would only need to mirror my design to make a complete dome.

To summarize, I divided the circle (essentially the frame of the habitat) into quarters, which helps with my goal of making my habitat easily transportable through simplifying the frame. The design repeats itself.

After understanding how to divide my frame, it was a matter of applying the Hoberman mechanism.

The Hoberman mechanism uses two identical rods connected by a joint, so I used the the equal constraint tools within Fusion to help me make the linkages of the shape I wanted. To construct the joints of the Hoberman mechanism, I used Fusion's circular pattern tools to make triangles within the circle's quadrant. I also offset my outer 8 meter diameter circle to create a lower-boundary for my linkages.

The number of triangles directly correspond with the amount of linkages my shape will use to expand and contract. Choosing this number was finding a balance between stability and expandability. With more triangles, i.e., more linkages, I gain expandability, but lose stability. Since I already knew my max sphere constraint was 8 meters, I chose half of 8-- settling on four triangles/ linkages for one quadrant.

Once I made the triangles, I sketched lines connecting each point to a joint point, alternating each time and creating the scissor-like mechanism of the Hoberman sphere. Then, I used each line as a guide to make a linkage through offsetting the line and giving it more dimension.

Using constraints, I was able to model the expansion and contraction of the linkages!

As mentioned in Step 1, I divided my frame into quadrants, which made designing the linkages easier. However, I still needed to connect these quadrant assemblies to make a larger frame (as well as allow another dimension in order to make a full sphere shape), so I created a simple rectangular connector piece which brought the linkage of one quadrant to another, as well as the linkages in the perpendicular direction together as well.

After a successful demonstration of the linkages in Fusion, I began sending the linkages to my printer. I printed my linkages and connector pieces and began assembling them to create the frame of the spheres using M2 x 4mm screws.

After connecting the linkages and connector pieces, I was able to create the domes!

My physical model spans 12 inches tall, totaling 24 inches for the complete double-dome design.

In this section, there are some photos of the linkages working in real life!

Here are some photos of the Fusion 360 assembly.

Phase 1 - Contracted sphere with parachute to help break the fall into an atmosphere (like mars). By having it deploy as a sphere instead of a dome, the habitat can have more rigidity and have a higher potential of surviving an orbital drop for deployment.

Phase 2 - The sphere then unfolds into two contracted domes, to better use the space available. A large sphere would have to high of a ceiling, and a non flat floor, which would make living more difficult. Domes on the other hand provide better protection and strength then a normal square structure, and are able to use more of the volume as floor space. The floor is also flat instead of round.

Phase 3 - The domes then expand to further increase volume. They can then be packed with stored furniture which folds into the structure, and other materials can be brought in through an airlock. The parachute can then be used again to cover the empty space in frame, and to make the entire structure more pill like, to survive any wind storms that may throw debris into the structure. The structure can also have the parachute covered with material to make a mound that uses the material from the planet, to better insulate and protect the structure. Solar panels would be placed outside of this parachute, in order to make energy for the habitat.

In an actual application of this design, I plan on using solar panels and renewable energy source to power the habitants.

With the double-dome design, one dome can be used for work (research and professional fields) whereas another for play (exercise and improving quality of life), allowing the habitants to have a healthy and balanced work-life balance through a physical division in space. The splitting of the domes also allows for an airlock to be made, where one dome can have a human environment, where the other allows air in and out, so that astronauts can leave the base.

NOTE: For furnishing this home, I used these GrabCAD resources:

• Bed
• Office Suite
• Toilet
• Sink
• Water Recycler

The Hoberman Habitat gives new meaning to expanding life into space! With a small sphere, researchers can start new societies in space without worrying about the volume their spaceship can hold.

The design process from start to finish has been difficult; however, being able to model something in Fusion 360, and then bring it to life using a 3D printer and some screws was extremely rewarding. For future iterations of the Hoberman Habitat, I want to create foldable and multi-use furniture, to create even more efficient habitats.