چكيده به لاتين
Nowdays, automobile safety systems such as electronic stability control and anti-lock braking systems are becoming increasingly popular among researchers. Although these systems have good performance, however, they do not provide information about the contact patch of tire, e.g. frictional forces. In the work done in advance, these forces are calculated by various sensors such as strain gauge sensor, optical sensor, accelerometer, camera. The accelerometer and strain gauge sensors were more widely used. But to estimate the coefficient of friction, the strain gauge is not precise due to the local strain calculation. Accelerometer sensors have a higher accuracy than other sensors in order to measure the contact patch length.For this purpose, an accelerometer sensor is used in this paper. To do this, we first developed a two-dimensional model of the tire section. Then, with a 360-degrees revolution about the axis passing through the wheels, a full 3-dimensional model of tire sizes is produced with unequal elements. Accelerometer located in the center of the tire is used to calculate the contact surface length at the center of the tire and road contact area. Afterwards, the estimate of the inflation pressure in the tire and the vertical force estimation are determined by the relationship between the two parameters with the contact patch length, which was not calculated in advance of the two parameters through the contact patch length. Also, to check the behavior of the tire in the cornering, inspired by past research with the strain gauge sensor, two other accelerometer sensors located on the two edges of the tire, and after calculating the contact patch length on the outside and inside and through The ratio between these two lengths is to estimate lateral forces and tire torque. He then sought to find the relationship between the lateral force in tire and torque with the ratio of the contact surface length to the interior of the tire. then to find the relationships between the lateral force in the tire and torque with the ratio of the contact patch length. The proposed method has the ability to be used in different driving conditions, including maneuvering and direct movement. Also, according to the Brush formula, the friction coefficient value between tire and road is estimated. Investigating a three dimensional finite element model of a tire with a 175 / 505R13 specification showed good agreement between the numerical and experimental results provided in the literature. The error value is betweeb 3 – 7%. The results indicates the effectiveness of the proposed method to estimate the friction coefficient, which is an important parameter for various advanced automotive systems.
