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30 minutes already

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Problem in our community

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Water endless!

1963–1964 Water RaTIONINg

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One person wastes 290 l/day!

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How can we prevent this in the future?

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DropWise

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DROP

WISE

HKUGA PRIMARY SCHOOL proudly presents

Every Drop Precise . Every Choice Wise

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Original Idea

30 minutes

Waste Money

DropWise

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SDG goalS

DropWise

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Timer

Micro:bit

switch

Transparent case

Capacitor

Water flow causes

Micro:bit

to start timer

Micro:bit countdown

for 5 minutes

Micro:bit sends a signal

to the motor

to cut off the water

Hydroelectric

WARNING alarm

after 4 minutes

for 1 minute remaining

How it works

Our Solution is dropwise - prototype 1

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DropWise

PROTOTYPE 1

Water flow

Rotating

Plate

Motor

gears

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micro:bit keep going after stopping water flow?

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Battery ? Capacitor ?

(store energy)

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connect electricity to micro:bit?

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Prototype 1 - Challenges

DropWise

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Timer + Temperature Device

how the switch works

dropwise - How it works - 2

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Connection to Water Tap

Connection to Hose

dropwise - prototype 2 (Structure)

Timer

Big Gear

Small Gear with Motor Underneath

Top View

Bottom View

Front

View

Micro:bit

Valve

Front View

⭐️Battery

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Motor (in blue)

dropwise - Structure of Valve

Timer

Internal View of How the Valve Works

Valve

Side View

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    • TIMER
    • Motor Movements

dropwise - CODING FOR 2 FUNCTIONS

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dropwise - how it works

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world’s first device

control water flow

manage shower time

show temperature

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Who needs this solution?

Market Opportunities

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EVERYONE

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Value

Save Time

Save Resources

Save money

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Survey

77.4%

spends >8 min

in showers.

87.1%

spends >10 min

in showers.

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Survey

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Looking Forward

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Our Journey

Understand strengths and weaknesses

October

February

March

April

June

December

Model + Coding

Practice Presentation

Prototype 1

and try out

Final presentation

in HKUGAPS

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Prototype 2 making and testing

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Big Bang Academy Global STEAM Public Speaking Competition 2026

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Best Sustainable

Technology Award

DropWise

Buy + Collect Materials

Improve

Model + Coding

Pitching Day

Set targets

January

November

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Credits

​

Cleva

Tang

Ocean Chan

Jasper Wong

Ms

Fiona

Emma Wong

Quinn

Ng

Krystabelle

Ko

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THANK YOU FROM

Every Drop Precise . Every Choice Wise