In 2019, [PERSON] et al. [6] introduced a novel nonlinear dynamic model for spur gears. This model considers several factors such as pressure angle variation with time, gear backlash behaviors, gear gravitational effects, geometrical imbalance in mass, and excitations. A study by [PERSON] (2020) [7] looked at how spur gears move and react by starting with the gears in the backlash and using meshes that change over time and with bearing stiffness. Hysteresis nonlinearities were described by a set of differential equations by Huo 2019 [8], [PERSON] [9] used the load-side encoder's information to achieve high precision; the method accounted for backlash by using a precise joint-control method. The load-side encoder information effectively compensated for the backlash effect in a feed-forward manner. Dead zone linearity has been extensively used by the researchers for defining the backlash [10; 11; 12]. The accuracy and performance of servo tracking are improved if the estimation of dead zones is done correctly, as done in [11; 12]. To deal with backlash, a predictive control strategy was applied in [13] for an electric power train system with backlash. To overcome the immeasurable system states, the researchers used a switched Kalman filter. [PERSON] [14] presented a novel backlash compensator for automotive drivetrains, realized via real-time model predictive control. Since predictive control strategies need to perform calculations over and over, different adaptive control methods for backlash compensation were also created by [15; 16; 17; 18; 19; 20; 21]. An adaptive robust controller was designed without using the inverse backlash model developed by [PERSON] et al. [20] for robot manipulators with unknown backlash in robot joint gears. The fact that the controller did not use the inverse backlash method made it less complex. [PERSON] et al. (2018) created a boundary controller for a flexible robotic manipulator to handle the system's backlash [21]. [PERSON] et al. [22] devised an adaptive technique for compensating for backlash in a solid-ducted rocket, utilizing touch-state observation. The strategy successfully reduced the duration of the transition and minimized the hysteresis effects on the control system. [PERSON] et al. [23] devised a method to estimate vibration torque as well as system states. A designed extended-state observer used those estimated parameters to obtain feed-back and feed-forward signals. [PERSON] et al. [24] also came up with a new way to fix servo systems that have backlash. It is called variable gain-switching accurate differential observer-based compensation control for servo systems with backlash. The variable gain technique was devised to accurately predict the unknown system states and adjust for the influence of backlash based on the mathematical model of switching backlash torque. The estimation was conducted using the Kalman filter, taking into account the backlash as a parameter and incorporating it as a state in the dynamics. The backlash was estimated using local measurements of the DFIG system. [PERSON] et al. [25] used dual-motor drives to compensate for backlash. One of the drives acted like a rotational spring to close the gap between the gears. Thus, it is responsible for eliminating backlash. Two degrees of freedom backlash-free mechanisms have been established by using the drive-anti-drive mechanism through cooperative control by [PERSON] et al. [26].