In a recent study published in Engineering, a team of researchers led by Wenyu Zhang from South China Agricultural University has developed a groundbreaking cotransporter system that combines a tracked rice harvester and transporter for fully autonomous harvesting, unloading, and transportation operations.
The key innovation of this system lies in the proposed dual-unloading mode, which includes two distinct methods: harvester waiting for unloading (HWU) and transporter following for unloading (TFU). In the HWU system, the harvester halts and summons the transporter when its grain tank reaches a specific threshold. In contrast, the TFU system allows the transporter to follow the harvester during the straight sections of harvesting, enabling continuous unloading without the need for the harvester to stop. This dual-mode approach significantly enhances operational efficiency by minimizing downtime and optimizing the use of resources.
To orchestrate the complex collaborative operation between the harvester and transporter, the researchers designed a harvesting-unloading-transportation (HUT) strategy. Leveraging the concept of finite-state machines (FSMs), they broke down the process into eight primary stages and constructed a state-transition chain. This modular design not only simplifies the control logic but also enables easy maintenance and upgrades, ensuring the system's adaptability to various field conditions and operational requirements.
The team conducted extensive simulations and field-harvesting experiments to validate the effectiveness of their system. The results were remarkable, with the cotransporter system achieving a harvest efficiency of 0.42 hm2∙h−1. Field tests demonstrated that the HUT collaborative operation strategy seamlessly integrated path planning, tracking control, inter-vehicle communication, and collaborative operation control, allowing the system to complete the entire process autonomously.
This research represents a significant step forward in the development of unmanned farming technology. By addressing the challenges associated with multi-vehicle collaboration and complex operational processes, the new cotransporter system and HUT strategy have the potential to transform the agricultural industry. Future work will focus on further optimizing the system's performance, improving sensor accuracy for real-time path planning, and exploring additional applications in other crops and farming scenarios.
