Analysis of the Impact of Combine Harvester Dynamics on the Accuracy and Reliability of Ultrasonic Stubble Height Measurement

Ultrasonic sensing has emerged as a popular technology for non-contact proximity and material characteristics measurement due to its simplicity, reliability, and cost-effectiveness. This study investigates the influence of combine harvester dynamics, including vibrations, movements, and variations in terrain, on ultrasonic stubble height measurement accuracy through a comprehensive analysis of field data and experimental findings. The accurate measurement of stubble height in agricultural fields is crucial for optimizing post-harvest operations and ensuring efficient crop management practices. By exploring the interactions between the combine harvester's operational dynamics and the performance of ultrasonic sensors, this research aims to identify key factors affecting measurement precision and consistency. The experimental setup involves mounting ultrasonic sensors on the combine harvester to capture real-time ultrasonic measurements during harvesting and post-harvesting operations. Data is collected under varying field conditions, including different cutter heights of the combine harvester and different ground speeds, to assess the impact of dynamic factors on measurement outcomes. This study investigates the effects of machine vibrations by gradually increasing the operational vibrations of a combine harvester from low to high levels. Additionally, it examines signal filtering techniques aimed at improving the robustness and accuracy of ultrasonic stubble height measurements in dynamic harvesting conditions. The findings offer valuable insights into the challenges and opportunities related to the use of ultrasonic sensors for measuring stubble height amidst the dynamic environment created by combine harvester operations. By understanding and addressing the factors affecting measurement accuracy, farmers, researchers, and agricultural technology developers can improve the effectiveness of ultrasonic measurement and monitoring systems. Keywords: Combine Harvester, Harvesting Efficiency, Harvest Residue Detection, Machine Vibrations, Precision Agriculture, Stubble Height, Ultrasonic Sensor, Non-Contact Sensing, Uniform crop cut, Stubble Management