## 6 Experimental Results
The results for normalized estimated perturbation for the end effectors of both the master and slave systems are shown in Figure 14. The profile corresponding to the master device is shown as a red line, while that for the slave is shown as a blue line. The results for the 2\({}^{\text{nd}}\) link of the master device (blue line) and the slave device (red line) are presented in Figure 15. It is evident that slave's 2\({}^{\text{nd}}\) link follows the master's 2\({}^{\text{nd}}\) link effectively using SMCSPO. The space allows the 2\({}^{\text{nd}}\) link to move between 0 and 90 degrees. The maximum value of the profile is 60.13 degrees at 26.55 s on the time scale. Figure 14: Normalized estimated perturbation of end effectors for master and slave. Figure 10:0 Master/slave trajectories for the 2\({}^{\text{nd}}\) link. The mismatch profile for the trajectories of the 2\({}^{\text{nd}}\) link for the master and slave devices is shown in Figure 10:1 The maximum mismatch value for the corresponding trajectories was 0.55 degree at 21.68 s on the time scale. The estimated perturbations for the 2\({}^{\text{nd}}\) link of the master and the slave are presented in Figures 17 and 18, respectively. It can be seen that the maximum value of perturbation was 45.69 N-m at 21.47 s for the master's 2\({}^{\text{nd}}\) link and 543.9 N-m at 21.47 s for the slave's 2\({}^{\text{nd}}\) link. One important fact is that the estimated perturbation profiles are the same for both the master and slave devices, but in opposing directions. Figure 10:2 Error between master and slave trajectories for the 2\({}^{\text{nd}}\) link. Figure 10:3 Estimated perturbation of the master’s 2\({}^{\text{nd}}\) link. The normalized estimated perturbations of the master device's end link (red line) and the slave device's 2\({}^{\text{nd}}\) link (blue line) are presented in Figure 10:4  
The results of the experiments for the base trajectories of both the master and slave devices are shown in Figure 10:5 The base trajectory of the master device is shown as a red line, while that of the slave device is shown as a blue line. Accurate tracking of the slave shows the effectiveness of the proposed scheme. The available space for the base allows its movement between 0 and 360 degrees. The maximum value of the trajectory profile is 100.38 degrees at 23.2 s on the time scale. Figure 10:6 Normalized estimated perturbation of the 2\({}^{\text{nd}}\) link for the master and the slave. Figure 10:7 Estimated perturbation of the slave’s 2\({}^{\text{nd}}\) link. The mismatch in the tracking of the base is presented in Figure 10:8 The maximum mismatch was observed at 143.3 s on the time scale, with a value of 0.859 degrees. Figure 10:9 Error between the base trajectories for master and slave. Figure 11:0 Estimated perturbation of the base for the master. Figure 11:1 Master/slave trajectories for the base. Figure 23 presents the experimental results for the end effector and the second link achieved using SMCSPO. At the start, for the first 4.1 s, the end effector and the 2\({}^{\text{nd}}\) link could not move. After 4.1 s, only the end effector was able to move until 13.5 s. Again, the end effector and the 2\({}^{\text{nd}}\) link could not move for another 0.7 s (i.e., from 13.5 to 14.2 s). Then, the 2\({}^{\text{nd}}\) link moved separately for 1.3 s (i.e., from 14.2 to 15.5 s). After that, the end effector and the 2\({}^{\text{nd}}\) link moved simultaneously for 6.5 s (i.e., from 15.5 to 22 s). Finally, the end effector and the 2\({}^{\text{nd}}\) link could not move for 7.1 s (i.e., from 22 to 29.1 s). The slave device followed the trajectory of the master device accurately. The maximum trajectories of the end effector and the 2\({}^{\text{nd}}\) link were 82.97 and 42.04 degrees, respectively.