Development of a Human–Machine Interface Implemented in Smartphone for a Variable Rate Fertilizer Applicator

This paper presents the development of a smartphone application to be a human-machine interface for a solid fertilizer dosing system with electric drive for seeder-fertilizer with dosage variable rate. Many facilities are available in applications in the commerce, communications, industry and services sectors, such as Uber, whatsApp and Airbnb. However, there are many innovation opportunities and challenges in family agriculture for sustainability and food security. We use the design methodology to develop a modular smartphone application with ergonomics and usability with the App Inventor 2 for Android operating systems and is suitable for a variable rate fertilizer doser. The dosing system consists of a feeder, driven by an electric motor of direct current powered by a high current battery, the drive is given through a power drive commanded by an Arduino microcontrolled platform of the MEGA series. And also has accessories such as Bluetooth, GPS module and Incremental encoder to give feedback in the control system. The application makes Bluetooth communication with the Arduino, which allows the user to enter the line spacing and amount of fertilizer, and display on the screen the values of the angular velocity, speed of travel, latitude and longitude of the seeder-fertilizer. It is intended to provide technological support so that workers can have a practical system of strategic decision making.