Recently, Rheological Fluids (RFs) have been used in several applications related to mechanical and mechatronic fields due to their unique properties such as RFs are smart materials with controllable rheological properties. Also, it is important to understand the working principles and what mechatronics systems entails, which includes among others, sensors, actuators, signals, simulations and modeling. All these topics are explained in detail in this chapter according to the concepts and results reported in the literature. The chapter was divided into four parts, first part contains a brief description of mechatronics engineering, in particular definition, history, and different types. Whereas second part was focused on the rheological fluid and gives an overview of RFs (electrorheological fluid (ERF) and

magnetorheological fluid (MRF)). While the third part was focused on some modern application in mechatronics and robotic systems including; telerobotic surgery device that uses MRF, drive by wire cars, smart dampers in vehicles and other systems, smart clutches and the trunk robotic arm manipulators using rheological fluids in their joints for precision output. Finally, in the last part the authors suggested some future applications for ERF and MRF in cutting-edge technology

2.1 Definition of Mechatronic

The term mechatronics was originally defined by the Yasakawa Electric Company. In trademark application documents, Yasakawa defined mechatronics in this way (Kyura and Oho 1996, Mori 1969). The word, mechatronics, is composed of “mecha” from the mechanism and the “tronics” from electronics. In other words, technologies and developed products will be incorporating electronics more and more into mechanisms, intimately and organically, and making it impossible to tell where one ends and the other begins.