Crash Science: Building 3D Printed Crumple Zones
This is one of our favorite projects, and one of our oldest.
You, the students, get to learn the basics of parametric 3D
modelling, the same CAD technology that's used to design things
like car engines (and the STEM Explorer vehicle!), and use your
new skills, along with your knowledge of Newton's laws of
physics, to build a working crumple zone for the STEM Explorer
staff to 3D print and test. You'll not only learn about mass,
acceleration, force, and momentum, but also how they apply to
real-life safety concerns. Even better, the CAD skills you pick up along
the way just might be the beginning of a career in engineering.
This project is designed to meet Michigan science standards
HS-PS2-1, HS-PS2-2, HS-PS2-3, and HS-ETS1-2, and ISTE standards 1c, 2b,
3d, 4a, 4b, 4c, 4d, 5a, 5b, 5c, 6d, 7a, 7b, 7c, and 7d. For more
information, you can read our
standards summary document,
and the ISTE's standards page.
You can see the rubric that your teacher will use to grade
your project here.
We'll have a lot to get done in the next few weeks. Not only will
you be learning CAD modelling and designing your crumple zones from
scratch, the STEM Explorer team will also need to manufacture everyone's
crumple zone with their 3D printers, and we'll have to test your crumple
zone and give you the test data to analyze and interpret.
Step By Step
- The STEM Explorer team will deliver an introductory lecture,
somehow. If we can, we'll come to your school in person and give
a brief introduction to the project, but if that's not possible,
we'll do the same thing over videoconference, or if worst comes
to worst we'll have you watch our
- We'll also try to give you an introduction to parametric 3D
CAD modelling in Onshape, usually on the same day as the
introductory lecture. If we can't give a live tutorial, either
in person or over videoconference, or if you just want to review
the material later, you can follow along with our
- Now the real fun begins. You'll need to collaborate with
your teammates to brainstorm a crumple zone idea. When you're
done, you should have a rough sketch to turn in to your teacher
and to the STEM Explorer staff.
- Once you've finished your sketch, you can begin modelling
your brilliant crumple zone idea in Onshape. You should create
one document and then share it with everyone in your team, so
that you can work on your design together with your teammates,
and with your teacher and the STEM Explorer staff, so we can
help you out if you get stuck.
- When it's time to turn your design in, you should
create a final revision of your design in Onshape and tell
your teacher and the STEM Explorer staff that it's ready for
printing. The STEM Explorer staff will then load your design
into the STEM Explorer's 3D printers and set them to work making
it. (This part could take a long time, because there will
probably be a lot of parts to print, and 3D printers are
- When the printer finally finishes your crumple zone, it has
to get tested. We connect your crumple zone to a special
canister that has an accelerometer mounted inside it, then drop
it into our special drop-test chamber from a height of about
nine feet. If possible, again, we'll bring all the equipment out
to your school and do the test with you live, but if we can't do
that, we'll have you watch the testing over videoconference, or
as a last resort you'll be able to watch the video of your test
when we e-mail it to you along with your accelerometer data.
- Speaking of e-mails: When we perform the drop tests, we'll
be recording slow-motion video of the inside of the drop-test
chamber while we drop your crumple zone into it, and the
accelerometer inside will be measuring, well, the acceleration
that the whole assembly experiences when it impacts the bottom
of the chamber. After the testing is complete, we'll send you
the slow-motion video and the accelerometer data, so you can
analyze them and see how well your crumple zone worked. Your
teacher will decide what exactly you do next.