HC-SR505 PIR Motion Sensor

PIR (Pyroelectric InfraRed) sensors are designed to detect the infrared (IR) light emitted by objects within their detection area. The HC-SR505 sensor is one such example of this technology. It offers user-friendly operation by automatically providing a HIGH signal when motion is detected in its coverage zone. However, this HIGH signal has a duration of approximately 8 seconds, which may be considered a drawback. Regrettably, addressing this limitation through software modifications is not feasible; it likely requires a hardware solution involving capacitor or resistor replacement. The module's operational voltage range spans from 4.5V to 20V, and as per the datasheet, it can detect movement within a range of up to 3 meters. In this tutorial, we will explore how to effectively integrate the HC-SR505 sensor with the Arduino Platform.

It boasts a generous 100-degree viewing angle. Due to its remarkably compact size, ultra-low-voltage operation capability, exceptional sensitivity, and unwavering reliability, this sensor finds extensive application in various electrical devices and equipment.

Upon initial power-up, the sensor initiates a calibration process by acquainting itself with the ambient infrared (IR) characteristics of its surroundings. Essentially, it adapts to its environment to discern what constitutes motion. This calibration phase typically lasts around 15 seconds.

During this calibration period, it's important to note that false triggers may occur, and as such, any detections within this timeframe should be disregarded. Ensuring minimal motion within the sensor's field of view during self-calibration is crucial to prevent interference with the calibration process.

Remarkably, the module maintains an exceptionally low power consumption, drawing a mere 70uA of current even when active. This efficiency allows for the possibility of powering it through a digital output pin from a microcontroller if desired. However, it's essential to account for the 15-second startup time in such scenarios.

Lab Objectives

Understanding a fundamental understanding of Passive Infrared (PIR) sensors and how they work and their applications in various projects.

Familiarize with the HC-SR505 PIR Motion Sensor, its physical components, pinout, and specifications.

How to connect the HC-SR505 sensor to an Arduino Uno R3, ensuring proper wiring and power supply.

Demonstrate how to write Arduino code to detect motion using the HC-SR505 sensor and trigger actions when motion is detected.

Address common issues and errors that may arise during sensor setup and usage and how to troubleshoot them effectively.

Evaluate understanding through quizzes, hands-on demonstrations, and their ability to successfully complete a project using the HC-SR505 sensor and Arduino Uno R3.