Design and Realization of A Low Cost Clinometer based on ADXL345 Sensor, Ultrasonic Sensor, and Android based Smartphone

摘要

Manually height measurement using a measuring instrument with a limited scale range can hamper the performance of building construction activities. To deal with this problem, a device is needed to be able to measure the height of the building more quickly, has a larger measuring limit, and is easy to use on the measurement of the inner building that is on a flat plane. This paper describes a prototype of clinometer using ADXL345 accelerometer sensors connected to Android-based smartphones. Other components that build this system are HC-SR04 ultrasonic sensor, HC-05 bluetooth module, and Arduino Uno microcontroller. The proposed system is able to connect with Android-based smartphones through the connection of the HC-05 bluetooth module, retrieving distance data through ultrasonic sensor readings and elevation angle data via the ADXL345 sensor, sending or receiving data from an Android smartphone to Arduino and vice versa, calculating the approximate height, and display it on the Android based smartphone. Experimental results show that applications installed in Androidbased smartphone can display the results of approximate height. The proposed instrument can quickly calculate the approximate height of a building with an error percentage of 2.5 %. The maximum distance from the proposed instrument to the building is 1.75 m.