Park-Aid

Description: This circuit was designed as an aid in parking the car near the garage wall when backing up. LED D7 illuminates when bumper-wall distance is about 20 cm, D7+D6 illuminate at about 10 cm, and D7+D6+D5 at about 6 cm. In this manner, you are alerted when approaching too close to the wall. All distances mentioned before can vary, depending on infra-red transmitting and receiving LEDs used and are mostly affected by the color of the reflecting surface. Black surfaces lower greatly the device sensitivity.

The described circuit functions as a proximity sensor for vehicles, utilizing infrared (IR) technology to detect the distance between the car's bumper and a wall. The circuit employs a series of infrared LEDs and photodetectors to measure the distance based on the reflection of emitted IR light from the wall.

The primary components of the circuit include three infrared LEDs (D5, D6, D7) and a photodiode or phototransistor that serves as the receiving element. The circuit is designed to activate the LEDs in a sequential manner based on the detected distance. When the vehicle is approximately 20 cm from the wall, LED D7 lights up, providing an initial warning. As the vehicle approaches 10 cm, LED D6 is activated alongside D7, indicating a closer proximity. Finally, at a distance of 6 cm, all three LEDs (D5, D6, and D7) illuminate, signaling that the vehicle is very close to the wall and caution is required.

The sensitivity of the circuit is influenced by the characteristics of the infrared LEDs used, as well as the color and texture of the surface that reflects the IR light. Lighter and smoother surfaces tend to reflect IR light better than darker or rough surfaces, which can absorb more of the emitted light, thus affecting the detection range.

The circuit can be powered by a standard voltage source, typically around 5V to 12V, which is suitable for automotive applications. Additional components such as resistors may be included in the circuit to limit the current to the LEDs and protect the photodetector from excessive voltage. A microcontroller or comparator circuit can also be integrated to manage the LED activation logic, ensuring that the correct LEDs light up at the appropriate distances.

Overall, this parking aid circuit enhances safety by providing visual feedback to the driver, helping to prevent collisions with garage walls or other obstacles while reversing.This circuit was designed as an aid in parking the car near the garage wall when backing up. LED D7 illuminates when bumper-wall distance is about 20 cm., D7+D6 illuminate at about 10 cm. and D7+D6+D5 at about 6 cm. In this manner you are alerted when approaching too close to the wall. All distances mentioned before can vary, depending on infra-red transmitting and receiving LEDs used and are mostly affected by the color of the reflecting surface. Black surfaces lower greatly the device sensitivity.