# Structural Design and Study of an Integrated Cutter System Based on Machine Operation
## 1 Introduction  
In the construction of subway transportation, water pipelines and other urban tunneling projects, shield machines play a crucial role [1]. Shield machines mainly rely on the dense cutter system in a cutter plate to realize the cutting of rock and soil in front and complete the rock-breaking function. However, in the process of shield tunneling, machines need to face a variety of harsh service conditions, such as vibration impact, heavy load, sediment blockage, etc., and the cutter inevitably undergoes wear and damage and therefore needs to be regularly inspected and parts have to be replaced [2]. At present, manual cutter-change technology is mainly divided into atmospheric-pressure cutter-change technology and pressure cutter-change technology [3, 4], such as compressed-air pressure cutter change, saturated submersible pressure cutter change, saturated gas pressure cutter change, atmospheric-pressure cutter change, frozen cutter-plate cutter change, and so on. Although the above technical solutions provide technical support for manual cutter change, reducing the difficulty and risk factor of cutter change, cutter changers still operate in a complicated environment with high pressure and high humidity, air pollution, etc., and may even face risky accidents, such as drilling-face collapse and mud backflow [5]. As the domestic and foreign research on unmanned and intelligent tunnel boring equipment continues to deepen, so the automation of cutter-change operations has become an inevitable trend to promote the development of tunnel boring technology. However, it is difficult to realize mechanical automation disassembly and assembly due to the existence of many fragmented parts and complicated disassembly steps in the traditional cutter system(TCS) [6]. Therefore, the design of a machine-friendly integrated cutter system (ICS) has an indispensable role in realizing automated cutter change in tunnel boring. For the research on integrated cutter systems, many universities and companies have carried out research and development work. The early research of the French company BOUYGUES [7] and the German Research Center for Artificial Intelligence (DFKI) [8] is most prominent. BOUYGUES proposes a linkage-type integrated cutter system, which is used in conjunction with the cutter-changing robot TELEMACH. It works by rotating the screw at the top of the cutter system, which drives the linkage mechanism downward to realize cutter installation. This linkage-type integrated cutter system has the advantage of simple installation, but it is prone to jamming in the harsh environment of the shield machine [9]. The DFKI designed a slider-type integrated cutter system for use with the robot HECTOR. This also has the advantage of fewer disassembly processes, but the slider structure results in higher machining requirements and lower forces [10]. In recent research work, Hongrun Construction, in conjunction with Shanghai University [11; 12], proposed an eccentric locking cutter system, which can realize the locking of the eccentric circular mechanism with the cutter box by grasping the cutter by the end-effector and rotating it at a certain angle. The Dalian University of Technology [13] designed a wedge swing-type cutter system, which is based on the action of the continuous ammunition supply mechanism of automatic firearms and transforms the lifting action into a wedge swing. The rotation of the bolt drives the fork to lift and move, realizing the retraction and unfolding of the locking wedge. Based on the contradiction solution theory of invention problem solving (TRIZ), Central South University [14] proposed a slide-groove-type cutter system. It consists of only four components and has a simple disassembly action. In addition, during the service of a shield machine, the cutter system will be constantly affected by external environmental factors, such as impact load and vibration.