Fun with Symmetry (Smart Mirror Reflection & Rotational Symmetry Bot)
Source: Stemoto Original
Explore line and rotational symmetry using acrylic mirrors and a motorized rotary turntable. Color sensors scan patterns rotated 90°, 180°, 360°, detecting rotational symmetry order (Order 2, Order 4).
Categorisation
Props & Materials Required
- •Motorized rotary turntable platform (stepper / DC motor)
- •Acrylic mirror kaleidoscope V-stand (60°, 90°, 180°)
- •TCS3200 RGB color sensor module
- •ESP32 controller board
- •0.96-inch OLED display screen
- •DFPlayer Mini MP3 module + 3W speaker
Step-by-Step Instructions
Place Pattern Tile on Turntable
Place a 4-pointed star tile on the motorized turntable.
Rotate Turntable 90 Degrees
Press 'Rotate 90°'. Motor turns tile 90°. Color sensor scans pattern RGB values.
Check Pattern Match
Sensor reads identical RGB layout at 90°, 180°, 270°, and 360°!
Rotational Symmetry Order Proof
OLED displays 'Rotational Symmetry: ORDER 4'. Speaker announces: 'Order 4 Rotational Symmetry! Looks identical 4 times per turn!'
Why It Works & Notes
Symmetry includes both line symmetry (mirror reflection) and rotational symmetry (looks identical when turned). A motorized turntable rotating shape tiles past color sensors quantifies rotational symmetry order.
Maths Mela Class 4 Chapter 11: Fun with Symmetry | STEM Tech: Stepper Motor Rotation & RGB Pattern Symmetry Verification — crystalline symmetry in chemistry and silicon wafer inspection.