100% Analog Automatic Sunshade and Climate Ventilation

Watch the video demonstration here:

https://youtu.be/RXHaAxvZAV8?si=O8APF8dfDH-ntdds

Staying cool in the heat often requires manual adjustments or complex electronics. This project presents a 100% analog, eco-friendly solution built with upcycled components from old CD/DVD drives. It combines an automatic sunshade that tracks the light position with an intelligent thermal cooling fan that adapts its speed based on ambient temperature.

Why Analog?

No coding, no microcontrollers (like Arduino or ESP32), and no complex digital setup. The system relies entirely on basic electronic principles using operational amplifiers (LM358), a dual audio power amplifier (TDA2822), and a 555 timer.

Key Features

Automatic Sunshade & Seating Tracking: Uses light-dependent resistors (LDRs) and a TDA2822 H-bridge driver to keep the shade and seat aligned with the sun.

Temperature-Proportional Fan: Uses an NTC thermistor and LM358 comparator to turn on the fan and scale its speed as the temperature rises.

Upcycled Design: Built primarily from salvaged CD/DVD drive mechanisms, reducing e-waste.

Electronics & Components :

1x TDA2822 Audio Amplifier IC (used as Dual H-Bridge motor driver)

1x LM358 Operational Amplifier (used as thermal comparator)

1x NE555 Timer IC (astable pulse generator)

1x IRF3205 N-Channel Power MOSFET

2x Light Dependent Resistors (LDR)

1x NTC Thermistor (10K-ohm)

1x 10K-ohm Potentiometer (for temperature threshold calibration)

Resistors: 1.8k-ohm / 30k-ohm / 680-ohm / 3 • 15k-ohm

Capacitors: 2 • 10 nF, 1nF

1x Red LED & Power Switch (S_1)

2x 18650 Li-ion Batteries (3.7V each, connected in series for 7.4V)

1x Perfboard / Prototyping Board

Mechanics & Salvaged Parts

1x Old CD/DVD Drive mechanism (tray gear motor for shade + pickup carriage mechanism for seat)

2x DC motor ( fan and for solar tracker )

Cardboard/Plastic fseat mockup

Connecting wires & solder

The core mechanics rely on repurposed components from an old CD/DVD drive.

Sunshade Movement: The disc tray mechanism provides horizontal linear motion to shift the sunshade screen as light position changes.

Seat Tracking: The optical pickup carriage is used to keep the seat mockup perfectly aligned with the shade.

Watch video demonstration here :

https://youtube.com/shorts/FkGwXi66I4Y?si=ColHV0UVdTUdbsJt

https://youtu.be/7f6GJEYnwEU?si=0MpyKG4wGu0IKuwk

The electronic system is 100% analog and operates without any microcontrollers. It is divided into three functional blocks:

Sun Tracking (H-Bridge Driver): A TDA2822 dual audio power amplifier is used in a bridge configuration to drive the tray motor (M2). Input voltages are provided by a voltage divider created by two 10k Light Dependent Resistors (LDRs) and 15k resistors . The differential lighting drives the motor direction to keep the shade centered.

Thermal Sensing & Fan Control: An NTC thermistor (R4) and a 10 k potentiometer (R3) set the temperature threshold for the LM358 operational amplifier. When the temperature rises, the LM358 triggers an IRF3205 N-channel MOSFET to power the cooling fan motor (M1).

Signal Generation: An IC1 555 timer operates in astable mode to provide reference timing and signal modulation for the circuit.

Power Supply: Powered by two 18650 Li-ion batteries in series (7.4 V total), monitored by a red LED indicator (L1) with a 680 ohm current-limiting resistor (R6), and controlled by a main switch (S_1).

Watch the video demonstration here :

https://youtu.be/RXHaAxvZAV8?si=AObQtvcw0iOVEGMQ

https://youtu.be/7f6GJEYnwEU?si=-VPpsRA83vYn5_RC

https://youtube.com/shorts/FkGwXi66I4Y?si=UVPq1dux3fHNo355

Performance & Testing

The physical prototype successfully proves that autonomous shading and thermal regulation can be achieved without microcontrollers or complex programming.

Light Response: The LDR sensor array reacts instantly to shifting light sources, moving the shade panel and seating carriage smoothly along the CD/DVD drive mechanism.

Thermal Response: The NTC thermistor accurately detects local temperature increases and dynamically drives the cooling fan. Once ambient temperature cools down, the fan turns off automatically.

Future Improvements

While this functional prototype features shading and active air cooling, future iterations could integrate a misting system (mister/brumisateur) triggered by a secondary analog humidity or temperature threshold to provide additional evaporative cooling during extreme heat conditions.