## 1 Introduction
It could display the working status of the harvester parts in real time and centrally control the harvester [15]. The British Massey Ferguson Harvester Company had developed a combine harvester farmland star system. It could detect the working failures of the combine harvester in time and issue an alarm prompt, which greatly reduced the failure rate of the combine harvester [16,17]. Japan's Kubota Company designed an intelligent-monitoring device by integrating electronic-sensing technology, a display device, a positioning system, a geographic information system, and a remote-sensing measurement and control system. It was applied to the combine harvester, and the intelligent-monitoring function of the combine harvester during the harvesting process was realized [18]. In addition, [PERSON] et al. developed a microcontroller-based embedded system with a digital display and audible warning units [19]. Domestic research started late. Most of the existing research [3,20, 21, 22, 23] systems were aimed at single-vehicle operations. Among them, information collection, processing, and analysis were all completed by the vehicle terminal. For example, [PERSON] of Jiangsu University had developed a remote video-monitoring and fault-monitoring system for combine harvesters. It used the WCDMA network as the wireless transmission network to realize the long-distance transmission of data. The fault solution was fed back to the airborne terminal through the remote-monitoring center to help the on-site staff in troubleshooting [24]. [PERSON] et al. designed a remote-monitoring system based on GPS and GPRS. It could realize functions, such as data communication and analysis, data storage and query, real-time display of the position of the agricultural machinery, and track play back [25]. [PERSON] et al. developed a farm SMS center system integrating GPS positioning and wireless communication functions. This could solve the problems of low efficiency and poor timeliness of agricultural machinery operations in China. It could reasonably schedule agricultural machinery according to the actual production conditions of agricultural machinery [26]. The Institute of Remote Sensing of Peking University designed a set of agricultural-machinery-monitoring and management system. It realized the real-time operation monitoring of agricultural machinery, the collection of agricultural multi-source information, and the simple functions of agricultural machinery scheduling [27]. The Bei'an Administration Bureau designed and developed a set of agricultural machinery operation supervision management and service system. It was based on B/S network transmission for Heilongjiang Agricultural Reclamation Hongxing Farm [28,29]. Lovol Heavy Industry Co., Ltd. had built an IoT cloud service system for agricultural equipment, which realized functions, such as service fleet scheduling and remote diagnosis of agricultural machinery. It developed the \"Zhi Nong Lovol\" APP, which was convenient for users to obtain vehicle condition information, operation information, and fault information through smart phones in a timely manner [2]. The whole agricultural mechanization cloud service platform was developed by the China Academy of Agricultural Mechanization. It could realize the functions of agricultural machinery operation data monitoring, operation quality statistics, task scheduling, etc. It was suitable for various types of agricultural machinery and equipment, such as sowing, plant protection, and harvesting [30]. In summary, at present, domestic combine harvester operation monitoring, automatic driving, and other information technologies have been initially developed and applied. System functions are more focused on monitoring. However, due to the lack of remote operation and maintenance means, the application of operation and maintenance technology lags behind, especially in the research blank stage of fault diagnosis and operation maintenance. It cannot meet the requirements of high reliability operation of agricultural machinery.