Research on the Control System for the Conveying and Separation Experimental Platform of Tiger Nut Harvester Based on Sensing Technology and Control Algorithms

Enhancing the intelligence of Tiger nut harvesting equipment with the advancement of agricultural machinery is imperative. Mismatches between excavation feed rate and conveying-separating capacities hinder the efficiency of Tiger nut harvesters. A visualized Tiger nut harvesting platform was designed to address this, incorporating parameters like conveying speed, torque, vibration frequency, and excavation depth. The platform features a mechanical execution part and an automatic control system with speed, torque, frequency, and depth control modules. Mechanical design analysis defined control parameters and methods for each module. An adaptive B-PID controller was proposed for trajectory tracking, combining backstepping and PID. A control model accounting for motion damping and error compensation was derived. Simulink simulations compared B-PID with backstepping controllers, showing B-PID’s robustness and effective trajectory tracking. Actual experiments assessed mechanical-control coordination using relative error metrics. The results showed that the maximum relative error of rotation speed was 3.8%, the maximum relative error of frequency was 3.67%, and the maximum relative error of excavation depth was 1.5%. Correction models for excavation depth and excitation frequency parameters were established. This study offers a theoretical framework to advance the intelligent design of tiger nut harvesting machinery.