## 3 Results and Discussion
### Selection of an Optimal Solution for the Generation of Structures  
The geometric results of optimising the CPM positioner's links 3 and 4 are shown in Figure 11. The results show the geometric shape before and after optimisation using the Generative Design method. The results obtained indicate that it is becoming necessary to change the approach to manufacturing the components (links) of the positioning mechanism. In the original CPM solution, commercially available aluminium structural profiles were used as the basic element for the mechanism. Their use required only the cutting of a specific profile to a defined length. When these profiles are replaced by structures generated by Generative Design methods, it becomes necessary to use profile casting or 3D printing techniques in the manufacturing technology. Traditional manufacturing methods could fail in this case due to the complexity of the geometry that forms the mechanism component. However, the numerical tests carried out indicate that the results obtained concerning the original solution are characterised by a lower mass and better strength parameters, i.e., the level of von Mises stress and displacement under applied moments. \begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Parameter** & **Limit Volume \textless{}75\%** & **Limit Volume 75\%** & **Limit Volume 80\%** & **Limit Volume 85\%** \\ \hline Starting mass, [kg] & \multicolumn{4}{c}{0.61516} \\ Valid value, [\%] & Not generated & 74.8 & 78.6 & 83.2 \\ \hline \multicolumn{5}{c}{Parameters of link 1 after Generative Design optimisation} \\ \hline Displacement, [mm] & - & 8.3405 \(\times\) 10\({}^{-4}\) & 8.3404 \(\times\) 10\({}^{-4}\) & 8.3400 \(\times\) 10\({}^{-4}\) \\ Von Mises Stress, [MPa] & - & 0.0285831 & 0.0285827 & 0.0285812 \\ Final mass, [kg] & - & 0.452 & 0.476 & 0.504 \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Results of Generative Design optimisation of link 1—material 316 Stainless Steel. \begin{table}
\begin{tabular}{l c c} \hline \hline
**Parameter** & **Limit Volume \textless{}90\%** & **Limit Volume 90\%** \\ \hline Starting mass, [kg] & \multicolumn{2}{c}{0.63436} \\ Valid value, [\%] & Not generated & 86.2 \\ \hline \hline \multicolumn{3}{c}{Parameters of link 2 after Generative Design optimisation} \\ \hline Displacement, [mm] & - & 1.45 \(\times\) 10\({}^{-3}\) \\ Von Mises Stress, [MPa] & - & 52.3150 \\ Final mass, [kg] & - & 0.538 \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Results of Generative Design optimisation of links 2—material 316 Stainless Steel. Figure 12 shows the final results of the optimisation of drive members 1 and 2 of the CPM positioner and their original shapes. In the case of optimised links 1 and 2, they can be manufactured using casting techniques or a CNC machine. The optimisation of these links slightly altered the original shape of the links, but ultimately reduced the mass of the entire positioner and significantly reduced the von Mises stress. Comparative Analysis of Kinetic, Potential, External, and Total Energy before and after Generative Design Optimisation  
The simulation model was rebuilt in ANSYS Workbench to determine how the optimised motion apparatus links changed the dynamic parameters of the CPM device design. Using the Rigid Dynamics toolbox of ANSYS Workbench, a dynamics study was performed to determine how changes in the mass and shape of the positioner members affected the potential, kinetic, total, and external energy of the CPM device's positioning system. The results of the studies, in the form of a graph of the change in energy values over time for the assumed actuator motion pattern, comparing the results before and after Generative Design Optimisation (GDO), are shown in Figure 13.  
From Figure 13, we can read that before GDO, the maximum value of potential energy is 286.04 J, kinetic energy is 0.20813 J, external energy is 2.8355 J, and total energy is 148.67 J.