Introduction: Lunchbox for People With Hemiplegia

Team Members: Chris Lobo, Ryan Ravitz, Alex Romine

Why We Did It:

An individual at Seven Hills has limited mobility in one hand has difficulty using his or her lunchbox. Although it is not explicitly stated in the design review, Seven Hills has requested a product that fits the preferences of the individual and, most importantly, is easily operable with one hand.

Useful Files:

Before building this lunchbox, take a quick peek at the requirements document our team made. It contains a useful chart of the criteria for the lunchbox and how we scored our prototypes.

We have also attached the background research we conducted regarding the lunchbox.

Visit the following link to view the scoring matrix for our initial lunchbox designs.

All files are available for download below:

Step 1: How to Use the Lunchbox

Watch this user video to see this lunchbox in action!

Step 2: Gathering Materials and Tools


  1. Aquarius Lunchbox- $14.99
  2. Silicone Rubber Feet - $3.99 (comes with 6)
  3. Neodymium Disc Magnets - $8.99 (comes with 6)
  4. Adjustable Laptop Strap (2)- $15.96
  5. 1" Cabinet Knob (w/ Screws) - $0.98
  6. D-ring picture hangers (2) - about $4 (can be purchased at a retail store)
  7. 1/8" Rivets - $7.49 (purchased at a hardware store)
  8. Glue


  1. 3D printer
  2. Power drill- equipped with 1/8" drill bit
  3. Rivet gun
  4. Scissors
  5. Matches
  6. A binder clip

Step 3: Prepping the Box

Use the binder clip or another tool to remove the clasp from the front of the lunchbox. This will allow room for the new knob mechanism.

Step 4: Cutting the Strap

Use scissors to cut a length of 7 or 8 inches out from one of the shoulder straps. This will be used for the magnetic strap. Use the matches to burn the frays off.

Step 5: Drilling Holes

Use the power drill with a 1/8" drill bit to create four holes on the top of the box and two holes on the left and right sides of the box. Measurements are given in the above images.

Tip: Drill through the strap and the holes on the top at the same time. Also, make sure the holes on the left and right sides line up with the D-ring picture hangers.

Step 6: Riveting

Use the rivet gun to rivet the strap onto the top of the box. First, insert the rivet through the hole in the strap and the hole in the top of the lunchbox. Then, place the rivet gun over the rivet and squeeze until the rivet fastens the strap to the box.

Tip: This may take more than one squeeze. Also, bracing the bottom of the lid with a hollow cylindrical object like a tape roll can help keep the box from bending.

Repeat the same process with the two D-ring picture hangers on the sides of the lunchbox.

Step 7: Creating the Knob Mechanism

To create the CAD design, first you must open Onshape and make a rectangular prism. Then extrude a hole through the model so that a screw can go through it. The knob will be screwed onto on the other side of the screw. Next, extrude a small circular indent on the top of print. The diameter of this circle should be slightly larger than the width of the screw head and should be extruded into the surface of the prism and be as tall as the screw head. This will allow the screw head to be flush with the top of the model. Next, make a larger circular indent on the top of the model. The larger indent is a space where the magnet can be glued into the model and should be sized accordingly. After these steps, you must make a space for the strap to pass through the model. On the side, extrude a rectangular slit that is wide enough for the strap to pass through. This allows us to make a hole in the strap after which a screw can pass through the strap and the print and hold the print in place on the strap.

You can also click here to view a pre-built CAD design.

Once the design is printed, use the drill to create a hole through the end of the strap. First, line up the knob attachment mechanism so that it does not block the handle too much. (Because of the dimensions of the box, this mechanism will be a tight fit.) Then screw through the attachment and the hole. Apply super glue into the indentation for the magnet, insert the neodymium, and let the glue dry. Add the knob to the other end of the screw. In conjunction with the magnet on the knob mechanism, glue another magnet to the inside of the box to ensure a tighter seal.

Unfortunately, lining up the knob perfectly without getting in the way of the handle can be difficult. If one or more magnets is not flush with the end of the lunchbox, the ridges can become crimped, hammered, or otherwise flattened. Be very careful with this step.

Step 8: Finishing Touches

Congratulations! You're almost done.

Just hook the second shoulder strap onto the D-ring picture hangers and attach four rubber grips onto the corners of the bottom of the lunchbox.

Step 9: Improvements and Extension Projects

The features of this lunchbox are fully functional, but they could still be improved upon:

  • A better base lunchbox could be researched and selected.
  • Insulated material could cover the box for protection and heat.
  • The magnet strap CAD design could be modified for better press fitting of the neodymium magnet.
  • The corners of the CAD design could be rounded.
  • A grip-like material could be added to the bottom of the box in a layer.
  • The handle could be moved or removed to provide more space for the knob mechanism.

Other assistive technology projects would work well with this, such as:

  • Different opening mechanisms- More ideas can be found in the scoring matrix, but other opening mechanisms (such as a button-operated mechanism) could be tested and applied to a similar lunchbox.
  • Different base lunch boxes- An AT lunchbox could be created using a plastic lunchbox or a lunchbag.
  • AT Tupperwares - Tupperwares often require two hands to open because of the suction between the lid and the bowl. A lever or some other opening mechanism could allow the Tupperware to be opened with one hand.

Step 10: Resources and References

Works Cited (from background research):

AbleData. (2017). Retrieved from
Centers for Disease Control and Prevention. (July 2013) Facts About Cerebral Palsy. Retrieved from

Centers for Disease Control and Prevention. (December 2016) About Stroke. Retrieved from

Des Roches, J. (2017) . Assistive Technology. Retrieved from

Eunice Kennedy Shriver National Institute of Child Health and Human Development. (December 2016). What Are Some Types of Assistive Devices and How Are They Used? Retrieved from