This Is a Work Period, Not a Lesson

There's no new concept to introduce today — you already have everything you need from your Design Packet. These four sessions are for turning your concept sketch into a physical launcher.

Teams will move at different speeds, and that's expected. A mechanism that looked simple on paper often needs a mid-build redesign once you're actually holding the materials — that's normal engineering, not a sign you did Sessions 14–15 wrong.

Bungee safety still applies every session, not just the day you got certified. Recheck anchor points and cord condition every time you test a pull.

Build

Construct Your Mechanism

Work from your Design Packet's concept sketch. If reality forces a change from what you sketched, that's fine — note the change and why in your notebook as you go, not after the fact.

Troubleshoot As You Go

Expect real problems: parts that don't fit, a mechanism that binds, an attachment point that isn't strong enough. Treat each one as a quick Test → Reflect → Iterate loop inside the build: observe the failure, diagnose its cause, then change one thing.

Checkpoint Timing

At the Session 18–19 spot-check, your instructor checks every team: is your mechanism physically functional, regardless of polish? A team that's badly behind at that point needs to flag it now, not wait until the milestone ends.

If Your Team Finishes Early

Don't sit idle, and don't start "polishing" indefinitely. Start preliminary data collection — a few practice pulls, logged the same way you will for real in Sessions 20–22. It's a genuine head start, not busywork.

Checkpoint

By the Session 18–19 spot-check, your instructor confirms:

• Your mechanism physically exists and can complete a launch cycle
• Your team can point to your chosen IV's physical control point on the mechanism (where pull distance is measured, or where angle is set)
• No bungee safety protocol from Sessions 14–15 is being skipped

"Functional" is the bar here, not "finished" or "polished" — that distinction matters, because Sessions 20–22 need real time, not a squeezed leftover.

Reflection

Answer these on your own. Reflections are individual, even when the rest of the session was team work.

1. Which client- or research-derived criterion in your decision matrix turned out to matter most once you were actually building? Did your original score predict what happened?
2. Sessions 20–22 ask you to test across a range of settings for your IV. Looking at your finished mechanism, what do you expect the realistic range of settings to be?

Submit

Keep a build log as you go — the date, what changed from your design, and why. It is the only written team deliverable this milestone, and it is easiest to fill in while you still remember the reason for a change.

Beyond the log, this milestone is graded as a hard checkpoint via your instructor's direct spot-check, plus your individual reflection.

Milestone Complete