"One servo deploys two sensors — simpler, lighter, fewer failure modes than two actuators."
Pond safety
35s
"A debounced ultrasonic guard cuts forward drive at obstacleStopMm before the robot can hit anything; keeping the wheels clear of the recessed water slots is the operator's job, done by stopping short and sampling with the arm."
Self-hosted firmware
35s
"The robot is its own infrastructure: it brings up its own WiFi AP, and the RC page, diagnostics page and live data page are all served from flash."
Engineering depth
35s
"We deliberately kept the sensor set minimal — mandated sensors plus one ultrasonic — cutting failure modes; the turbidity sensor runs through a calibrated voltage divider."
Data pipeline
40s
"Every reading streams to serial and JSON; the file drag-drops into our offline visualiser with arena replay."
Only claim what is on the robot. Judges ask follow-ups — the rulebook scores teams down for components they cannot explain.
Day 2 — Closing Night Case Competition (40 pts)
Phase
Details
Problem reveal
Scenario given at the start of the night — unknown in advance, no single correct answer
Preparation
1 hour to build a response from Day 1 data
Presentation
Up to 3 minutes + Q&A; multiple members must contribute (teamwork is scored)
1-Hour Preparation Plan
Time
Task
0–5 min
Open the saved results.json in the visualiser; verify all samples render
5–15 min
Read the scenario; pick which readings are most relevant
15–30 min
Build the argument: data → environmental conclusion → recommendation
30–45 min
Draft the 3-min script; choose visualiser views for the projector
45–60 min
Practice run + Q&A rehearsal; assign speaking segments
Argument Template
Opening (30s):
"Our robot collected [N] readings across four terrain types.
The data shows [key finding]."
Data per terrain (30s × 4):
"In [terrain], turbidity was [X] NTU — [clean / moderate / turbid].
Soil moisture was [Y]% — [dry / healthy / waterlogged]."
Recommendation (30s):
"We recommend [specific action] because [data-backed reason].
The greatest concern is [terrain] due to [specific reading]."
Limitations (20s):
"Point-in-time snapshot; single run; ±10% sensor band;
sector labels are operator-tagged; path is an estimate."
Closing (10s):
"Both sensors were calibrated against reference values before the run."
Acknowledging limitations is scored positively — tradeoff handling is an explicit Cat 6 criterion.
Q&A Preparation
Question
Response approach
"How accurate are your sensors?"
"Calibrated against reference samples before the run; the turbidity curve was refitted after adding the voltage divider. Target ±10% per Cat 1."
"Why remote control instead of autonomous?"
"The rulebook permits RC, and we built RC only. Operator sector-tagging guarantees correct labels and eliminates navigation failure modes — accuracy is worth more points than autonomy."
"How do you avoid the water hazards?"
"The operator stops short of a slot and samples with the arm, so the wheels never cross one. The ultrasonic guard only prevents forward collisions — slot avoidance is driving, not sensing."
"How do you know you didn't sample the same spot twice?"
"The operator tags each sample by sector against a 12-sample checklist."
"What are your data's limitations?"
Name them proactively: single run, point-in-time, path is a speed-model estimate, ±10% band.