Introduction: Defying Gravity - Designing and Building a Tensegrity Table

My name is Adam Spirko, and under the direction and supervision of my STEM teacher Mr. Scott Kutz (Westlake High School, OH.), I helped him create this Project Based Instructable to utilize and co-teach in our Engineering Honors Class.

In this lesson, students will make a tensegrity side table design and create their designs out of wood. The two pieces must be identical and connected with 5 chains (four corner chains and one middle chain). The table height must be between 2’-0” and 3’-0” and the top surface area should be between 200 square inches and 400 square inches. The chains connecting the pieces should be about 0’-⅛”.

Students will learn the inner workings of this complex physics problem and how exactly it works by making their own structure. This will allow them to learn that there are many layers and complexities in a product system and allow them to experience those systems. The term “tensegrity” dates back to the architect and inventor Buckminster Fuller, who coined the phrase to describe self-tightening structures using cables.

Duration: Eight or nine days

Vocabulary: 

  • Form - The visual parameters or aesthetic qualities of a part or system.
  • Function - The ability of a part or system to do its designed job.
  • Isometric - A projection drawing where all three dimensions are depicted at equal angles with no foreshortening.
  • Orthographic - A projection drawing where an object is depicted in three views (usually top, front, and right side)
  • System - A set of parts that work together in a network.
  • Tensegrity (Tensile Integrity) - System of isolated compressed components within a network of chords that are under continuous tension.

Technology Connections: 

  • Students will perfect their technical drawing skills by designing their table in orthographic and isometric drawings.
  • In the extra credit extension, students will extend their ideas further into the computer by designing a scale model of their table.

General Tips:

  • Refer to safety precautions above when using power tools


Differentiated Instructional Support:

  • If you need help, have an adult help you, especially with power tools or jobs that require multiple hands.
  • If student extra help getting started with ideas, walking them through different designs and styles can help.


Ohio's Learning Standards for Technology


Strand: Design and Technology

Topic 2: Identify a problem and use an engineering design process to solve the problem.

Content Statement: 9-12.DT.2.b. Implement, document and present a design process as applied to a particular product, process or problem.


Strand: Design and Technology

Topic 2: Identify a problem and use an engineering design process to solve the problem.

Content Statement: 9-12.DT.2.a. Evaluate a design solution using conceptual, physical, digital and mathematical models at various intervals of a design process in order to check for proper design and note areas where improvements are needed (e.g., check the design solutions against criteria and constraints).


Strand: Design and Technology

Topic 3: Demonstrate that solutions to complex problems require collaboration, interdisciplinary understanding and systems thinking.

Content Statement: 9-12.DT.3.d. Analyze the interactions within systems and between systems.

Supplies

  • Copy paper
  • Ruler
  • Pencils
  • Plywood sheet (3/4")
  • Square wood slats
  • Wire rope
  • Fasteners for wire rope
  • Eye hooks
  • Miter Saw
  • Circular Saw
  • Square straight-edge (T-square, triangle, etc.)
  • Drill
  • Drill bits
  • Wood and metal screws
  • 90 degree corner clamp
  • Wood glue
  • 220 grit sandpaper
  • Oil finish (my choice: Tried and True)
  • Sponge brush to apply oil
  • Large workstation
  • Any other tools that anyu components might require

Step 1: Pre-Assessment

  • Ask students if they know how tensegrity works.
  • Have students do their own research for 10-15 minutes and have them return to their seats to discuss findings.
  • Define possible shapes of the the table and brainstorm effective ways of creating tensegrity.
  • Choose materials of table (wood types, wires, etc.)
  • Review form and function principles
  • Have students brainstorm ideas

Scoring Guidelines:

Students must provide at least five unique isometric designs for their table on green paper, graded by quality of drawings. Choose two of their designs as possible final projects based on form and function.

Step 2: Post-Assessment

Part 1: Draw final table design as an orthographic sketch, with dimensions using instruments

  • Green paper, title block and border
  • Can be either by hand or by using CAD software

Part 2 (at home): Make the table and assemble it

  • Fasten using fasteners and glue

Part 3: Summary 

  • One paragraph (5-7 sentences) and at least three pictures
  • SSG (All caps)
  • Correct measurement format (Standard engineering dimensions)


SAFETY PRECAUTION: WOODWORKING POWER TOOLS

  • Always use eye protection when tool is on
  • Wear a dust mask when cutting wood
  • Always be under adult supervision when wielding the tool
  • Turn of and disconnect tools when not in use
  • Keep blades sharp


Attachments

Step 3: Measure and Cut Wood

  • Cut legs with Miter saw
  • Cut tabletops with jigsaw or circular saw
  • Make sure to measure and cut each piece one at a time to account for the thickness of the saw blade

Step 4: Create Table Legs

  1. Use corner clamp to square up the legs
  2. Drill into the corner of the leg
  3. Glue legs together
  4. Screw into the leg to fasten
  5. Repeat with other 3 corners until you have two complete legs

Step 5: Oil Wood

  1. Sand tabletops and legs
  2. Finish with oil of choice. I suggest Tried and True because it is all-natural and non-toxic
  3. Follow directions on the packaging

Step 6: Assemble Wood

  1. Mark out placement of legs and drill holes on wood (including four holes on each of the corners of the tabletops)
  2. Drill and screw holes to assemble both pieces of table

Step 7: Attach Eye Hooks

  1. Drill holes and screw in eye hooks, including the adjustable eye hooks
  2. Make sure to loosen adjustable eye hooks before attaching wires to make it easier to tighten

Step 8: Attach Wires

  1. Start with attaching both sides of middle wire
  2. Attach wires on the outside by attaching both sides of one wire, then attaching the wire in the opposite corner. Then, attach the last two wires.
  3. Tighten wires gradually, making sure the table stays level.

Step 9: Extension

On 3-D software like Inventor, have students design and print a scale model of their table, using thread instead of wire.

  • Only design one half of table, and print it twice

Step 10: Closing Thoughts

This project should be an interesting one for Technology and Engineering students everywhere, because it combined both technical drawing skills and carpentry skills, which are both important skills to take into the real world. It allows students to understand multiple facets of the design world and how they connect. Also, creating a rubric that grades the whole project will help students reflect on their project overall. I wish you all good luck on building this unique project.