## 3 Results and Discussions
### Design Analysis and Finite Elements
(1998) created a model of a moving vehicle performing the maneuver shown in Figure 4b and calculating forces on wheel hub using automatic dynamic analysis of mechanical systems (ADAMS) software. The mass of the vehicle body used was 1185 kg and the results for the maximum longitudinal force were calculated to be around 1800 N. This value, multiplied by a suitable safety factor, can be used as a clear guide of the amount of force the control arm should be able to support. A simulation done by [PERSON] et al (2019) was done to optimize the ride comfort requirements using ADAMS software. The study used the values of 4-12.5 Hz as the most sensitive frequency range of the driver seat vertical axis weighting frequency, and a value of 0.5-2 Hz for horizontal frequency ([PERSON] and [PERSON], 2019). Another optimization study was carried out by [PERSON] and [PERSON] (2019), using Radioss software. The control arm used in that study was of the wishbone type. The three-dimensional (3D) model was created using the computer-aided design (CAD) software, CATIA V5. The part was meshed using HyperMesh, by using 10 node tetrahedral elements with topology optimization. Spider webs were used in each loading slot to better represent load action. The optimization tool solved for stress values, given the factors of safety and displacement as constraints. The objective function was to minimize the weight and material used of this part. The optimized design of the wishbone showed a 30% weight reduction than the original design. A number of ribs can be observed, which replaced the solid middle web of the original design. These ribs can give the structure its needed strength while minimizing the weight as much as possible. [PERSON] et al (2019) proposed three different designs of the lower control arm, seeking to enhance stress distribution and weight of this part. The Z-shaped design was recommended due to its good stress distribution as well as it superior castability compared to the conventional design. The inclined web in the Z-shaped design is believed to enhance stress distribution; thus, preventing stress raiser zones. The results of the von Mises stress distribution are shown in Figure 8, which shows a maximum value of 199 MPa when subjected to a 5.5 kN longitudinal force. What can also be observed is the high density of zero stress regions (blue regions), which indicate that this design is not optimum. Another study by [PERSON] et al. (2019), applied on the lower control arm fabricated form nodular cast iron of 95% ferrite and 5% pearlite, was conducted to show the effect of casting defects, as well as loading cycles on the total fatigue life. Suspension arm samples were mounted in a fatigue machine and different loads were exerted to its end with a frequency of 10 Hz until failure. The study revealed that 90% of control arms have an infinite fatigue life at around 19 kN of maximum force for the cast iron suspension control arm. The study also concluded that the most common reason of fatigue failure results from oxides at the surface of the control arm. Regarding this research work, the application of WC3 multiple thermal aging treatments to the proposed trussed design may improve the fatigue performance to withstand more than 84,300 cycles, which is 134% enhancement of the part's life. It can be calculated by extrapolating the values of stresses of the original and new design with the values of T6 compared to WC3.