PSI - Issue 77

618 8 Francisco Castro et al. / Procedia Structural Integrity 77 (2026) 611–630 Francisco Castro/ Structural Integrity Procedia 00 (2026) 000 – 000 = × × 2 2 (15) This torque should balance the lateral moment related to point P by the centrifugal force at the center of mass, × × 2 = 2× ℎ × 2 ×( −ℎ ) (16) It’s important to note that the developed method accounts for the roll center height position ℎ . According to the Society of Automotive Engineers (SAE), the roll center is defined as the point located in the transverse vertical plane passing through a pair of wheel centers, where lateral forces act on the sprung mass without inducing suspension roll. In other words, it represents the effective pivot point of the suspension system as a whole. When lateral forces are applied in a direction parallel to the suspension swing arm, they are transmitted through the roll center, resulting in no suspension deflection and, consequently, no body roll. As soon as previous parameters (exception for ) are evaluated, the vertical coordinate of the center of gravity can be obtained by the following equation (17) , 2.2. Experimental method The main objective is to evaluate experimentally the vertical position of the vehicle’s centre of mass , in order to verify the accuracy of the proposed estimation methods (in motion). The results of the proposed methods will be compared with static methods. 2.2.1. Vehicle For that, a prototype vehicle (a RC-Vehicle, characteristics are presented in Table 1) will be used for the road tests, which was properly adapted (Figure 3) with the objective to test different driving scenarios and different vehicle loads positions. The vehicle doesn´t have any integrated sensor and is equipped with conventional steel coil springs. It should be noted that it is necessary to have access to the vehicle dimensions, vehicle mass and suspension stiffness. Both models developed are dependent on the vehicle suspension stiffness. The values of the suspension stiffness can be obtained from the vehicle manufacturer or by experimental tests. To estimate experimentally those values, Hooke Law may be applied, characterized by = − , where is the force (N) applied to the spring, is the spring rate (N/m) and x is the displacement (m). −ℎ = × × 2 × 2× ℎ × 2 −ℎ = × × 2 2× ℎ × = × × 2 2× ℎ × +ℎ (17)