# A Comparative Study of the Application of Different Commercial Software for Topology Optimization
## 5 Results  
As mentioned before, three case studies, a bell crank lever, a pillow bracket, and a small bridge, were optimized in this paper. The results of the optimizations, conducted in SolidWorks, ANSYS Mechanical, and ABAQUS, are presented in this section for both optimization cases--compliance TO with 50% weight reduction and compliance TO with maximum weight reduction. Table 2 contains the number of the design cycles, the optimization times, the weights after TO and after 3D preparation in percentages of the initial weight (IW), the maximum Von Mises stresses, and the minimum FOS against yield.  
In general, it was observed that in both optimization cases, ANSYS Mechanical used the lowest number of design cycles in all CAD models, except for the maximum weight reduction of the bell crank lever where Solidworks had fewer design cycles. The optimiza  
tion time is dependent on the executed design cycles. Therefore, the more design cycles used, the more optimization time is required. However, SolidWorks optimized the designs in less time compared to the other software, except for the 50% weight reduction of the bell crank lever where ANSYS Mechanical had the best optimization time.  
Concerning the weight reduction of the models, it was noticed that there was a difference between the weight of the optimized designs and their weight after the 3D preparation with the utilization of smoothing tools. In the first optimization case, the conducted 3D preparation in SolidWorks and ABAQUS increased the weight of their optimized designs from 0.3% for the bridge to 18.2% for the bell crank lever. On the other hand, the 3D preparation in ANSYS SpaceClaim decreased the weight of the optimized designs at a range of 0.4% of the bell crank lever to 9.8% of the bridge. It is important to take into account these weight fluctuations with the choice of the weight constraint at the optimization step. For example, for a 50% weight reduction of the bell crank lever, 56%, 47%, and 57.5% were the chosen weight constraints in SolidWorks, ANSYS Mechanical, and ABAQUS, respectively. In the second optimization case, the 3D preparation in ANSYS SpaceClaim decreased the weight of the designs in addition to. In the pursuit of the lightest design, the smoothing tools in ANSYS SpaceClaim gave the opportunity for higher reduction, ranging from 13.9% for the bridge to 34.7% for the pillow bracket. The designs in SolidWorks had higher weight again after the 3D preparation (0.13-10%). Finally, the 3D preparation in ABAQUS increased the weight of the bridge by 7%, while it decreased the weight of the bell crank lever and the pillow bracket by 7% and 4.3%, respectively.  
The maximum Von Mises stresses, found with the FEA before TO, were 11.7 MPa for the bell crank lever, 31.3 MPa for the pillow bracket, and 157 MPa for the bridge. In general, the designs with 50% weight reduction had maximum stress at the same level or even less than their initial designs, as was found in the validation studies. The maximum stress for the lightest designs was higher, as expected, but always smaller than the yield strength of their material. In the following sections, the results of each case study are presented in detail.