## 4 Key Enabling Technologies  
### Multi-Machine Cooperative Scheduling Based on IHHO  
In modern agricultural production, multi-machine cooperative operations have become a key approach to enhancing efficiency and reducing costs. Particularly in large-scale farming, a common model assigns primary machines (e.g., harvesters and seeders) to field operations, while auxiliary machines (e.g., transport vehicles) handle logistics and material transfer [38]. However, in multi-field environments, efficiently coordinating agricultural machinery, minimizing idle time, optimizing operational paths, and reducing energy consumption remain significant challenges [39]. Let the farmland set be \(F=\{f_{1},f_{2},\ldots,f_{k}\}\), the primary machines set be \(H=\{h_{1},h_{2},\ldots,h_{k}\}\), and the auxiliary machines set be \(G=\{g_{1},g_{2},\ldots,g_{k}\}\). Here, \(k\) represents the maximum number. The joint node belongs to farmland \(F\). To address this issue, this study proposes a path planning and scheduling optimization method for multi-machine cooperation, integrating [PERSON]'s algorithm with an IHHO algorithm [40]. This approach enhances coordination efficiency, reduces operational costs, and optimizes energy consumption in multi-field agricultural operations, ensuring high efficiency and stability. Figure 6: Integration of elements in agricultural cloud platform. This study develops a multi-objective scheduling model for cooperative operations, with the following optimization goals. The relevant variables and their meanings are shown in Table 1.  
1. Minimizing fuel consumption across in-field operations, transportation, and empty travel. 2. Minimizing scheduling costs, including machine travel costs, waiting costs, and penalty costs for time window violations. 3. Minimizing scheduling time, ensuring the shortest total time for all machines to complete their tasks. Objective function: \[min\ (E+C+T)\] (1) Constraints: \[\left\{ \begin{array}{l}\sum\limits_{i=1}^{F}\sum\limits_{h=1}^{H}x_{ijh}=1\\ \sum\limits_{i=1}^{F}\sum\limits_{g=1}^{G}x_{ijg}\geq 0\end{array} \right.\] (2) \[\left\{ \begin{array}{l}\sum\limits_{h=1}^{H}\sum\limits_{i\in\{A\}\cup F} \sum\limits_{j\in V\setminus\{A\}}d_{ij}\cdot x_{ijh}=\sum\limits_{h=1}^{H} \sum\limits_{i\in F}\sum\limits_{j\in F}d_{ij}\cdot x_{ijh}\\ \sum\limits_{g=1}^{G}\sum\limits_{i\in\{A\}\cup F}\sum\limits_{j\in V\setminus \{A\}}d_{ij}\cdot x_{ijg}=\sum\limits_{g=1}^{G}\sum\limits_{i\in F}\sum \limits_{j\in F}d_{ij}\cdot x_{ijg}\end{array} \right.\] (3) \[\left\{ \begin{array}{l}\sum\limits_{f=1}^{F}q_{f}x_{ijh}\leq H_{v}\\ \sum\limits_{f=1}^{F}q_{f}x_{ijg}\leq G_{v}\end{array} \right.\] (4) \[U_{h}=L_{g}=D_{i}H_{v}/U_{ch}\] (5) \[P_{hg}=\left\{ \begin{array}{l}C_{w}\Big{(}B_{i}-t_{hgf}\Big{)};\\ C_{i}\Big{(}t_{hgf}-E_{i}\Big{)};\\ 0,others;\end{array} \right.\] (6)  
Equation (2) indicates that each farmland can be accessed by only one primary machine and at least zero auxiliary machines. Equation (3) specifies that all primary machines and auxiliary machines depart from the machinery depot and return to the depot at the end of their tasks. Equation (4) states that the maximum load of the primary machine and auxil