# Approaches and Challenges in Internet of Robotic Things
## 1 Introduction  
Robotic systems have aided various technological developments during the previous decade. During the 1990s, robotic and network technologies were combined to expand the range of functional values of the robots [1]. IoRT was formulated to determine the structure in which sensor data from various sources are incorporated, and then explicated using local and distributed information. Thereafter, the data are used to monitor and verify things in the physical world [2, 3]. According to the IEEE Society of Robotics and Automation, a networked robot is described as \"a robotic device associated with a communication network through the internet or local area network (LAN) using standard network protocols such as TCP, UDP, or 802.11\". Robotic engineering systems are used widely in the industry today. Robotic systems are seen as critical components for humanity's growth in the new digital era. The robotic systems were turned into industrial IoRT applications when technologies of IIoT, AI, robots, intelligent networking, and electric mobility emerged [4]. Robotic things can now be connected to anything and everyone at any time, at any location, via various paths/networks and services. Due to new advancements in intelligent networking,Edge nodes, which are formed by networked robotic devices, might act as the pillar for IoRT applications in the future [4, 5]. The IoT and robotic technologies focus on two goals: (1) to provide information services for detection, sensing, and tracking, and (2) to create movement and interaction behavior. The development of IoRT has been improved due to the combination of the above two goals. According to [PERSON] [4], IoRT is defined as an active global network framework with self-adapting and self-configuring characteristics. The characteristics are based upon the standard communication protocol (rules for data access over the network) and the interoperability protocol (multiple system data exchanges). In this technology, to make decisions and act on various sets of rules, virtual and physical robotic things with varying degrees of mobility and autonomy use intelligent interfaces, cognition, and connectivity. IoRT enables the collaboration of people, devices, processes, and technology with actuators and sensors [1]. IoRT performs various functions including human-robot interactions (HRIs) and robotic interaction services (ROIs). A robotic system requires necessary equipment, commonly a microphone, camera, LIDAR, RADAR, and even sensors for performing interactions and reactions [6]. HRI is built into a robot for assisted living facilities, hotels, etc. Due to IoRT and HRI, various robots are deployed to monitor the work continuously. During IoRT communications, the data leakage problem is a big issue for data exchange. Data leakage affects the privacy of customers. For example, a stage subjected to IoRT security risk is associated with the transmission of data to IoRT systems by sensing units and sensors. Sensing units transmit data to the IoRT system to detect physical environments, while sensors give information to the device [7, 8]. IoRT devices suffer from heterogeneity, interoperability, time variance, network inactivity, security, multirobot systems, quality of services, precise navigation, and standardization. This article discusses secure communication for IoRT devices to overcome leakage problems. This manuscript provides a review of the IoRT definition and technologies used in the functionalities of IoRT. The abilities of robotic components are very essential for the autonomous behavior of robotic things; various characteristics are illustrated in this article. Various organizations use architectures as per their requirements, and there are various architectures for IoRT devices. In this review, we discuss many IoRT architectures, among which five-tier architectures are the most advanced and feasible for intelligent IoRT devices.