Mobile robots have played a crucial role since their inception and the research in the field of mobile robotics is ever increasing day by day because they have vast applications. These robots have brought easiness and comfort to human’s life. There are different ways in which mobile robots navigate, e.g. some move autonomously while others have a human operator as their motion planner and executor. The involvement of a human operator gave rise to the idea of the development of teleoperated robots. Teleoperated robots have helped in planetary explorations, landmines clearance, and explosive materials handling in dangerous environments, e.g. they are actively involved in the radioactive material handling of the nuclear power plants. Telecontrol and teleoperation consist of a human operator, a control station, a communication medium, a slave robot, and the remote environment. Initially, a dedicated medium like a radio link was used as a communication link between the control station and the slave robot. The communication involved some delay in the data and signal transmission. The delay was constant and the control laws were modified according to the new scenario.The dedication of a specific link for the communication was costly and it could not attract many researchers. But with the advent of the Internet, the researchers started utilizing it for the development of teleoperated robots. The main advantage of the Internet is its availability and cost. But as the Internet is a shared medium, therefore, it has an inherent delay in it. This delay is random in nature. Apart from delay it also has other limitations like packet drops, duplication of data, out of order arrival of packets, etc. The design of a controller with such limitations was a challenging task. Therefore, different solutions have been proposed to develop a stable telecontrol of the mobile robot AutoMerlin. At first, the Event-based Control was implemented to limit the execution time of the input commands so that the robot remains stable even in the presence of a delay. After that fuzzy soft computing was employed to design a controller, which was immune to a network delay. It has two inputs, one input comes from the human operator and the other input comes from the sonar sensors which map the environment and calculate the distance to the obstacle and provide it to the speed controller for an appropriate output speed. An ancillary intelligence has been provided to avoid obstacles autonomously in case of connection loss between the human operator and the mobile robot. Finally, Time Domain Passivity Control has been implemented to design a bilateral controller. It is a non-model-based controller which doesn’t add any extra damping to the system and also there is no need to make any compromise on any parameter of the system. It is based on Two-port network. The controller has been designed with only one port active. Then, the work has been extended to design a bilateral controller with both ports active having a constant and stochastic delay and other network impediments using Time Delay Power Network approach. The force feedback has been rendered back to the human operator. Several experiments have been performed to test the performance and robustness of the controllers. The performance evaluation data hasbeen plotted. Stable teleoperation has been achieved and it has been deployed to the mobile robot AutoMerlin. In the end, the Probabilistic Neuro-fuzzy and ANFIS have been used to design a leader-follower setup of multiple mobile robots. A simulation has been done to visualize the performance of the proposed algorithm and the Probabilistic Neuro-fuzzy has been implemented on the real robot.
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