Automatic Sorting of Solid Wastes Using Sensor Fusion

Abstract

Nowadays solid waste is generated at an unprecedented rate due to rapid urbanization and industrialization. In the developing countries, recycling of useful materials from solid waste such as wood, plastic, glass and metal is severely constrained by limited door-to-door collection and poor means of waste sorting. Indeed, recovery of useful materials still relies on manual sorting, which is highly risky and hazardous for health. This paper details the design and implementation of an automated solid waste sorting system. The developed system is equipped with a programmable logic controller, an inductive proximity sensor, a capacitive proximity sensor, and a photoelectric sensor. Multi-sensor data fusion is used so that each material results in a different combination of sensor outputs. Once a material is identified, the controller makes a stepper motor rotate a defined angle to collect the material in its bin. Testing results show that the system is successful in sorting the four different materials.