## 5 Application Examples
### Heavy Roughing Operation  
A heavy roughing application can be defined as a turning operation with a large depth turning. These turning operations cannot be machined in a single pass unlike light roughing machining. For this reason, the fitness function for these turning operations considers the machining time evaluation more than the power consumption. Table 12 introduces the working specifications for this roughing operation. It sets an initial diameter and a final diameter to 100 mm and 40 mm, respectively,  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Features** & **GA Results** & **Closer Insert** \\ \hline ICmm & 8.73 & 6.35 \\ LEmm & 10.5 & 10.3 \\ REmm & 0.68 & 0.39 \\ WEP & false & false \\ Smm & 2.37 & 2.38 \\ AN & 7\({}^{\circ}\) & 7\({}^{\circ}\) \\ Angle & 65\({}^{\circ}\) & 60\({}^{\circ}\) \\ GRADE & 4325 & 4325 \\ \hline \multicolumn{3}{c}{**Cutting Parameters**} \\ \hline Closer insert & TCMT 11 02 04-UR 4325 \\ Depth of cut & 5 mm \\ Feed rate & 0.288 mm/r \\ Cutting velocity & 346 m/min \\ \hline \hline \end{tabular}
\end{table}
Table 10: Results of the light roughing operation example.  
Figure 12: Example of GA performance for light roughing operation.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Goal Variable** & **Variable** & **Evaluation** \\ \hline Power consumption & \(P\) & 5 kW \\ Machining time & \(T_{m}\) & 0.34 min \\ Euclidean distance & \(d_{evaluation}\) & 6.307 \\ Spindle speed & \(n\) & 2761 rpm \\ High machining condition & MC\_H & 40 \\ Low machining condition & MC\_L & 10 \\ Fitness function & _fitness_ & 225.69 \\ \hline \hline \end{tabular}
\end{table}
Table 11: Goal variables evaluation for light roughing operation example.  
which defines a total depth turning of 30 mm. Additionally, the total machining length is set to 100 mm. The geometrical information for this example is presented in Figure 13. The workpiece material is an unalloyed steel of 250 HB with a specific cutting force of 725 N/mm\({}^{2}\). Moreover, for this operation, the stability condition is set to \"Good.\" The machine specifications define a small lathe with a total power capability of 10 kW and a maximum spindle speed of 3000 rpm. Equation (28) shows the fitness function for this operation. The machining time has been weighted 10 times, while the power consumption has been weighted 0.5 times. In this way, the fitness function establishes that the solution must prioritize the machining time instead of the power consumption.  
\[fitness=0.5\frac{P_{net}}{P}+10\frac{T_{life}}{T_{m}}+\frac{Th_{d}}{d_{euclidean}}+ \frac{n_{max}}{n\frac{100}{MC_{-}H-MC_{-}L}} \tag{28}\]  
\begin{table}
\begin{tabular}{c c c} \hline \multicolumn{3}{c}{**Material Specifications**} \\ \hline Initial diameter & \(D_{i}\) & 100 mm \\ Final diameter & \(D_{f}\) & 40 mm \\ Machining length & \(L_{m}\) & 100 mm \\ Hardness & HB & 250 HB \\ Specific cutting force & \(K_{c}\) & 725 N/mm\({}^{2}\) \\ \hline \multicolumn{3}{c}{**Machine Specifications**} \\ \hline Main motor power & \(P_{net}\) & 10 kW \\ Maximum spindle & \(n_{max}\) & 3000 rpm \\ speed & & \\ \hline \multicolumn{3}{c}{**General Specifications**} \\ \hline Machine operation & CTPT & Roughing \\ Stability & / & Good \\ Toot life & \(T_{life}\) & 15 min \\ Threshold distance & \(Th_{d}\) & 10 \\ Range ap\_rec & ap\_rec & 0.01–5 mm \\ \hline \end{tabular}
\end{table}
Table 12: Working specifications of the heavy roughing operation example.  
Figure 13: Example of heavy roughing operation.  
Table 13 shows the results for the GA evolution, which are the obtained features for the GA algorithm next to the closer tool-insert in the dataset. This table also presents the suggested tool-insert and its cutting parameters for this operation. Furthermore, in Table 14, the evaluation for the goal variables, which define the performance for the reached tool-insert, is introduced.