Sensor-based Safety Alarm System for Injury Prevention in Chaff cutter machine

Abstract

Agricultural activities pose significant hazards, leading to high rates of fatal and non-fatal injuries, particularly with the increased use of farm mechanization. One common machine used in farming is the chaff cutter or chaff cutter, which can cause permanent upper limb (hand) injuries during operation. To address this critical issue, a microcontroller-based alarming system was developed to provide advance warning when a worker's hand enters the injury-prone zone of the chaff cutter machine. The system incorporated a passive infrared (PIR) sensor that detected infrared radiation emitted by the human body. Extensive testing was conducted under various conditions, including different distances between the sensor and the human hand, hand orientations, room temperature, and fodder temperature, using subjects of different age groups. The Response Surface Methodology (RSM) was employed to derive regression equations for these parameters. The optimal distance for sensor placement was found to be 125mm ahead of the identified danger zone on the feeding chute. The sensor system showed good response for pronated and supinated hand orientations, followed by the holding position, under different temperature conditions. A temperature range of 24 to 27°C was identified as ideal for optimal sensor performance. Additionally, the speed of hand movement or fodder pushing and the worker's response to the audible frequency were found to effectively alert them. The developed alarming system can significantly enhance safety measures in chaff cutter machines, mitigating the risk of upper limb injuries and improving the overall well-being, productivity, and economic status of farmworkers.