# A Critical Review of the Status of Current Greenhouse Technology in China and Development Prospects
## 5 Research on Chinese Greenhouse Technology
### Automation
[54] proposed a suspended-rail automatic variable-distance target spraying system that uses a laser sensor to measure crop position and spraying distance in real time, which can be used to solve the problems relating to the low level of automation in spraying machinery, low spraying efficiency, and lack of spraying equipment suitable for vertically grown crops. The results showed that, when compared with the fixed-distance mode, the automatic variable-distance mode increased pesticide application efficiency by 16.7% and reduced pesticide use by 29.6%. Research has also been performed on automated plant growing. [PERSON] et al. [55] designed a cucumber-harvesting robot based on machine vision algorithms for cucumber fruit recognition and detection using near-infrared spectral imaging. The results showed that the robot's recognition accuracy and success rate in effectively acquiring and grasping the correct area was 83.3%. [PERSON] et al. [56] developed a multitasking robotic transplanting work cell for greenhouse seedlings. The cell has a multi-gripper transplanting system designed to automatically pick up and plant entire rows of seedlings. The test results showed that the overall success rate of the transplanting operation was as high as 90%. Research on the development of smart agriculture in China has made great progress in recent years; however, there is still a big gap between research and commercial practice [57]. AI has the advantages of optimizing crop yields, water and fertilizer use efficiency, reducing pests and diseases, improving the sustainability of agriculture, etc. Key AI technologies include robotic systems for spraying pesticides, irrigation, and harvesting, bio-inspired algorithms for greenhouse automation, energy management, machine path-planning for UAVs, operation and scheduling problem solving, and image signal processing for pest and disease diagnosis [58]. A great deal of research has been carried out in China in this area. [PERSON] studied an intelligent greenhouse decision-making system based on machine learning, which overcomes the shortcomings of existing greenhouse decision-making systems that only consider the influence of a single environmental variable on the growth of plants (such as the air temperature), and conducts a joint analysis of greenhouse multi-environmental factors in combination with the optimal growing environments of related crops so as to determine a more accurate optimal greenhouse decision-making scheme [59]. [PERSON] researched machine-vision-based path recognition for agricultural shed robots to better realize their ability to move autonomously [60]. The fact that much research has already been carried out shows the importance China attaches to research in artificial intelligence (AI) technology; however, the research investment is less than that seen abroad. There are many advantages of automated greenhouses, such as improved productivity, reduced labor costs, and improved yield and quality of fruits and vegetables. The application of automated greenhouses in modern agriculture has gradually expanded. In the near future, with growing populations in China and internationally and increasing attention to food security and safety, automated greenhouses will quickly transform agriculture from traditional agriculture to modern agriculture, further improving the efficiency of fruit and vegetable production and better meeting people's demand for high-quality agricultural products. Despite the many research trials focused on the development of smart automated and robotic systems, the systems currently used in a small number of modern greenhouses in China mainly relate to automated irrigation systems, air temperature regulation systems, and ventilation systems. These automated systems include a small number of sensors, such as air temperature and humidity, CO\({}_{2}\), solar radiation, and soil moisture sensors.