Lab 13.1: Capstone Scaffold

~120 min. Pick your capstone project. Sketch a block diagram. Draw the schematic. List the components. Estimate the build time. Get instructor sign-off (or self-review using the checklist).

Goal: scope the capstone so week 14 ships a working artifact, not a half-finished experiment

Estimated time: 120 minutes

Prerequisites: weeks 1-12 complete; read CAPSTONE.md carefully

Steps

Step 1: Brainstorm 3-5 ideas (15 min)

In your lab notebook, write 3-5 capstone ideas. Each should:

• Use sensors + actuators + Arduino (the course's combined skill set)
• Be doable in ~12 hours of work
• Solve a recognizable problem (or simulate one)

Examples to seed thinking:

• Alarm: motion or door sensor triggers buzzer + LED
• Mood lamp: photoresistor or button changes RGB LED color
• Reaction-time game: LED lights, button responds, time measured
• Temperature alert: thermistor triggers fan or warning if room too hot
• Plant moisture: soil sensor (if in kit) → LED indicator + Serial log

Step 2: Pick ONE (15 min)

Criteria for picking:

• You can articulate the use case in one sentence to a non-electronics friend
• You have a reasonable plan for every component (sensor, brain, output)
• Build time estimate is in the 8-12 hour range, not 30+
• You actually want to build it (motivation matters for capstone week)

Step 3: Draw a block diagram (20 min)

Block diagram: boxes for major components; arrows for what flows between

Example for "alarm":

• Block 1: Motion sensor (or button as substitute) → senses motion
• Block 2: Arduino R4 → reads sensor, decides if alert
• Block 3: Buzzer + LED → outputs alert when triggered
• Optional Block 4: Reset button → silences alarm

Arrows show data flow (sensor → Arduino → output). The block diagram is the project at the highest level; you should be able to explain it in 30 seconds

Step 4: Draw the schematic (30 min)

The schematic shows every wire and every part. Hand-drawn is fine. Use standard symbols:

• Battery / power source as two parallel lines
• Resistor as zigzag or rectangle (with value)
• LED as triangle with arrows
• Capacitor as two parallel lines (with value)
• Transistor as a circle with 3 leads (B, C, E labeled)
• Arduino as a labeled box with pin names

Every wire is shown. Every part is labeled with its value. Power and ground rails are clear

Step 5: Component list (15 min)

Make a table:

Confirm every part is either in your kit or in your SETUP.md supplements. If something is not: source it now (Amazon Prime or similar; 2-day delivery is typical) or pick a different project

Step 6: Estimate the build time (10 min)

For each block: estimate the hours. Add 30% buffer for surprises

Example:

• Wire the sensor circuit: 1 hour
• Test sensor on its own with Serial debug: 1 hour
• Wire the output circuit (buzzer + transistor): 1 hour
• Test output on its own: 0.5 hour
• Combine; write integrated sketch: 2 hours
• Debug; iterate: 2 hours
• Polish; record demo video: 1 hour
• Write the 2-3 page write-up: 2 hours
• Buffer: ~3 hours

Total: ~13.5 hours over week 14. The course budgets ~6 hours of lab + the independent practice for the week; many capstones run over and that is normal. If your estimate exceeds 18 hours, simplify

Step 7: Self-review or instructor sign-off (15 min)

Self-review checklist:

• My one-sentence summary makes sense to a non-electronics friend
• My block diagram has 3-5 blocks, with clear arrows
• My schematic is complete (every wire, every part labeled)
• My component list is complete and all parts are accessible
• My time estimate fits in week 14 with reasonable buffer
• I have prototyped the riskiest part this week (week 13), not deferred to week 14

If all six boxes are checked: you're ready. If not: revise

Expected output

• One-paragraph capstone proposal in your lab journal
• Block diagram
• Schematic (hand-drawn OK)
• Component list table
• Time estimate
• Self-review checklist completed

Common pitfalls

• Picking a project you have not prototyped any piece of: week 13 is your last chance to surface unknowns. Build the smallest piece this week
• Component you don't have: if a part is not in your kit and not in the supplements, source it NOW or change the project
• Scope creep: "and then I'll add WiFi, and then I'll add a web interface, and then I'll add..." No. Pick the minimum viable feature set; ship that

Stretch (optional)

• Prototype the riskiest part of your capstone this week (week 13, not 14). If you have never used the SD card or the servo or whatever, do that now
• Write a one-sentence "what would v2 look like" note, separate from your scope. Future-you will appreciate having it captured

Lab 13.1 v0.1. The scoping lab. The week's most valuable hour is the one spent NOT building.