Fab-in-a-Box

Description:

Design and fabricate your own custom glider. Test its flight, then optimize its performance by adjusting the shape of its wings, tail, or body or adding a nose weight.

STANDARDS ALIGNMENT
Next Generation Science Standards (NGSS)
  • MS-ETS1-2: Evaluate competing solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.
  • MS-ETS1-4: Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.
  • MS-ETS1-3: Analyze data from tests to determine similarities and differences among several different solutions to identify the best characteristics of each that can be combined into a new solution to better meet the criteria for success.
  • 3-5-ETS1-1: Define a simple design problem reflecting a need or a want that includes specified criteria for success and constraints on materials, time, or cost.
  • 3-5-ETS1-2: Generate and compare multiple solutions to a problem based on how well each is likely to meet the criteria and constraints of the problem.
  • 3-5-ETS1-3: Plan and carry out tests in which variables are controlled and failure points are considered to identify aspects of a model or prototype that can be improved.
Common Core Standards (Math)
  • Represent and interpret data. (Grade 5)
  • Fluently divide multi-digit numbers using the standard algorithm. (Grade 6)
  • Represent and analyze quantitative relationships between dependent and independent variables. (Grade 6)
International Technology & Engineering Educators Association (ITEEA)
  • Make two-dimensional and three-dimensional representations of the design solution. (Grades 6-8)
  • Apply the technology and engineering design process. (Grades 6-8)

Activity Steps

1. DESIGN & EXPORT FILES

A. Design your parts.

  1. Open xDesign on the control computer.
  2. Open the file labeled "introductory activity: scalable gliders."
  3. Use the input boxes or sliders to adjust the shape of your glider's body, wings, and tail.

B. Export your file.

  1. Save files in .dxf format.
2. LASER CUT FUSELAGE

A. Connect laser cutter.

  1. Turn the lasercutter on and connect it to your computer via USB.
  2. Open xTool’s XCS software (download here).
  3. Select “connect device” in the upper righthand corner of XCS.
  4. Choose your laser cutter from the pop-up menu.

B. Import & format design file.

  1. Click the file folder icon in the upper lefthand corner. From the dropdown menu, select “import image.” 
  2. Choose your file.
  3. Select the circular handle to rotate your design as needed to fit onto your stock. 
    Note: do not resize within XCS! Remember: your design is parametric, and the slots are perfectly calibrated for the width of your stock material. If you resize outside of your CAD environment, the slots will also change.

C. Configure cut settings.

  1. Select “user-defined material” from the dropdown materials list.
  2. Combine all elements (lines) you want to cut on a single layer.
          To add or switch layers, click “move to.”
          Select “cut” under the “processing type” menu.
  3. Repeat the above steps for elements you want to engrave (raster) or score. All elements for each processing type should be combined into a single layer.
  4. Check settings:
          For 1/16” balsa wood, we suggest the following (power/speed/pass):
                Score: 40/150/1
                Engrave (raster): 30/200/1
                Cut: 100/15/1

D. Prepare laser cutter.

  1. Open laser cutter lid and place stock (balsa) onto honeycomb. 
  2. Manually drag laser head over center of stock.
  3. Close lid.
  4. Click “auto focus” and wait for machine to focus. 
  5. Open lid. Manually drag laser head to top left corner of desired cutting area.
  6. To check framing, click “framing” in XCS and then press the button on the machine. The laser head will frame the area to be cut. If it does not fit on the stock or overlaps a previous cut, adjust the starting position as needed.

E. Run cut job.

  1. Click “process” in XCS, followed by the button on the machine.

F. Remove pieces.

  1. Check to make sure all pieces cut through, and rerun (adjusting settings as necessary) if not. 
  2. Remove workpieces and scrap stock from machine bed.
  3. Close lid.
3. VINYL CUT WINGS & TAIL

A. Prepare the machine:

  1. Turn on by long-pressing the power button on its right side for 2-3 seconds.
  2. Install blade (skip if already installed).
          -Open hood.
          -On the tool carriage, pull the locking mechanism completely out.
          -Place the autoblade into the tool slot, making sure it is fully inserted.
          -Push the locking mechanism back into place.
          -Close hood.

B. Prepare cardstock:

  1. Use a light hold cutting mat (or one where most of its “sticky” has worn off.)
  2. Position your cardstock on the paper.
  3. Load prepared cutting mat into the machine.

C. Configure cut settings:

  1. In the silhouette software, turn on “line segment overcut.”

D. Run job:

  1. Click "send."

E. Remove pieces:

  1. Don’t peel the paper off the cutting mat!
    Instead, turn the whole thing upside down and peel the cutting mat off the paper.
4. 3D PRINT WEIGHTS

A. Load filament:

  1. On back of machine, hang filament spool on holder so filament unwinds clockwise.
  2. Insert filament into the PTFE tupe on the top back side of the machine.
  3. On the machine’s screen, select nozzle → – → bed heat, and heat the nozzle to the recommended temperature for PLA.
  4. Wait for the nozzle to heat up.
  5. On the machine’s screen, select nozzle → E → downward arrow several times until the filament comes out of the nozzle. 

B. Load print file:

  1. Select the file icon and select your file to start the print.
    (Note: the file provided for this activity has been pre-sliced. That means it has already been configured in the appropriate software to run on the printer. If you wish to run a different CAD file, you will need to slice it first. Please see the appropriate tutorial for this more advanced approach.)

C. Remove finished print(s):

  1. Use the scraper, provided, to gently pry the finished print off the bed. 
    (Note: you can also remove the magnetic bed by lifting the tab facing toward you. The bed is flexible; applying gentle pressure to bow it upwards can help release stubborn prints. Be sure to return the bed once done.)
5. ASSEMBLE

A. Slot finished pieces together:

  1. Insert wings through the slot in the plane’s fuselage (body).
    Make sure they’re centered; the notch will help keep them in place.
  2. Slot your tail into place.
  3. Clip your 3D printed weights onto your plane as desired! (Tape and pennies also work).
6. TEST & EVALUATE

A. Test it out: it's time to launch your plane!

  1. Mark your starting line and gently launch your glider forward. 
  2. Measure the distance it traveled. This should be linear distance: the forward distance between your starting point and ending point. Lay a tape measure straight out forward from your starting line to measure in feet and inches (SAE/Imperial) or meters and centimeters (metric). Don't account for diagonals: we just want its forward distance traveled.

B. Record your observations:

  1. In a design journal or on some scrap paper, note the distance your glider flew.
    (Note: sketch a quick drawing, or disassemble it and trace its parts as a way to label your design!)
  2. Write down any observations, like whether it nosedived, wobbled, or turned to one side or another before landing.

C. Repeat three times:

  1. Run at least three test launches with this design before making any changes. Record your linear distance traveled and any observational notes for each trial.
  2. Stand in the same spot and attempt to apply the same force for each launch.
  3. Calculate the average distance traveled: add each distance together, and divide that total by the number of trials.
          ( [trial #1 distance] + [trial #2 distance] + [trial #3 distance] ) / [three trials run] = average distance traveled
  4. Record this average distance alongside your other notes.
7. REDESIGN & REPEAT

A. Make a design change:

  1. Consider your glider's flight pattern and develop a cause-and-effect hypothesis for why it behaved the way it did.
          -Nosedive = too much weight toward the front.
          -Nose went up = not enough weight toward the front.
          -Turned to one side = bent or uneven wings.
          -wobbled during flight = uneven weight distribution or tail.
  2. Redesign one element of your glider: the body, wings, tail, or weight distribution. This is your independent variable. All features you keep the same are considered controls.
  3. Fabricate any new pieces needed to make your adjustment and assemble your new design.
  4. Sketch or trace your new design in your journal.

B. Test your new glider:

  1. Repeat your testing: run three test flights with your new design. Measure the distance traveled and note your observations for each trial. This is your  dependent variable.

C. Keep iterating:

  1. Continue to optimize your glider, redesigning one element at a time. Run three trials for each design, calculating and recording the average distance traveled.
8. REFLECT & EXTEND

A. Reflect & discuss:

  1. How did the changes you made influence the linear distance flown?
  2. Based on your observations, what changes could you make to further improve upon your design?
  3. Based on peer discussions, what shape body, wings, and tail do you think the optimum glider would have? Would it have any weights? If so, where?

B. Extend the learning:

  1. Graph your data! Plot and label a dot to represent each design’s average distance traveled. 
  2. Investigate other variables. What other design elements could you change? 
          Examples: weight/thickness of the wood/paper; (if using paper) roll or fold the edges of the wings or tail; add more weights; adjust the angle of the tailslot in the rudder, etc.

Made possible by generous support from: