In this topic, we applied the Fmincon function to the optimum question when choosing the structure of a 7-bar bearing steel bearing, divided into groups of the same size, including group 1 (1, 2 bars), group 2 (3, 4, and 5 bars), and group 3 (6, and 7 bars) with three fixed head points and two bearing points. Using the Matlab software code, we have identified the structures of each group of steel bars corresponding to the radius of 1.564 cm, 3.509 cm, and 4.724 cm, respectively. Through this, we can identify the 1, 2, and 3 bars that are resistant to traction; the 3, 5, 6, and 7 bars that are subject to compression; and the 4 bars alone that are not subject to the action of the force. The results show that using the optimal method, we choose the different sizes, thicknesses, and volumes of the pipe so that it best suits the technical requirements of the paper, to avoid waste of raw materials, affecting the economic cost.