# Mobile Robot for Security Applications in Remotely Operated Advanced Reactors
## 1 Introduction  
The report [1] published by the Idaho National Laboratory in 2016, in which revenue gap analysis was performed for 79 nuclear power plants (NPPs), found that 63 out of the 79 power plants lost money in the same year (Figure 1). The rising operation and maintenance cost of nuclear power plants was one of the major causes in this, and may jeopardize the continued operation of the plants, as utilities struggle to compete with the low prices offered by natural gas and renewable energy sources. Utilities are working hard on implementing modernization strategies to reduce the cost of generating electricity using nuclear power. The operation and maintenance (O&M) cost for NPPs accounts for almost 70% of the power generation cost (Figure 2), with 50% of it being a labor cost. Recent research found that physical security forces make up almost 20% of the workforce at some NPPs based on discussions with utilities and other stakeholders. Thus, reducing labor costs is essential for lowering the cost of operating an NPP. A good physical protection system (PPS) is designed considering vulnerability assessment in all its components that have validated performance measures established for operation. Any PPS design should meet the protection objectives within the operational, safety, legal, and economic constraints of the facility. The primary functions of a PPS are the detection of an adversary, delay of that adversary, and response by security personnel [3]. Figure 1: Revenue gap of NPPs in USA [1]. Figure 2: Contribution of O&M costs and fuel costs in coal, gas, and nuclear power plants [2]. The study presents a survey of research on the capabilities of dog robots for safeguarding nuclear power plants. As per the definition put forward by the International Organization of Standardization (ISO 8373) [4], \"robot is an automatically controlled, reprogrammable, multipurpose manipulator with three or more axes\" [5]. The history of robotics is quite fascinating. Once a part of movie fantasy, the inspiration taken from the movies has made it possible for the existence of robots based on different fields of applications including marine [6; 7], space [8; 9; 10], medicine and surgery [11; 12; 13], household and many more. The word robot was first introduced into the English language in 1921 by the playwriter [PERSON] in his satirical drama, \"R.U.R. (Rossum's Universal Robots)\". In this, the robots were introduced as machines that resemble people, but work tirelessly. But the early work leading to today's industrial robots can be traced back to the late 1940s, just after World War II, when research programs were started at the Oak Ridge and Argonne National Laboratories to develop remotely controlled mechanical manipulators for handling radioactive materials [14]. The use of external sensing mechanisms allows robots to interact with the environment in a flexible manner. The function of robot sensors can be divided into two major categories: internal-state and external-state [15]. While internal-state sensors deal with detecting internal variables such as arm joint position, which are used for robot control, the external-state sensors, on the other hand, deal with the detection of external agencies like touch, range, and outer dangers. Through this study, we plan on presenting a survey of research on the capabilities of dog robots for safeguarding nuclear power plants. Although the use of robots for physical security at NPPs is a relatively new research area to explore, robots have been used in power plants for a long time in other areas as well. For instance, the robot developed by Hughes Aircraft in 1958 was used to reduce human risk associated with the contaminated hazardous environment of a plant [15; 16]. In this research, the focus is on enhancing the performance of a proposed physical security robot designed for patrolling the perimeter of a power plant.