چكيده به لاتين
The interaction between the tire and the road is crucial for determining the dynamic behavior of a road vehicle, and the road–tire contact forces are key variables in the design of traction, braking, and stability control systems. Traditionally, road–tire contact forces are indirectly estimated from vehicle-dynamics measurements. The emerging of the “smart-tire” concept (tire with embedded sensors and digital-computing capability) has made possible, in principle, a more direct estimation of contact forces. In this thesis, a comprehensive Flowchart algorithm for estimating the vertical force applied to the tire in the cornering motion is present. Due to the advantages of accelerometer sensors compared to strain gauges, this thesis uses an accelerometer sensor to estimate the vertical force on the tire on the road. To use the tire displacements obtained from the tire acceleration signals, there is no need to transfer the acceleration obtained in the accelerometer body unit and this also makes it easy to operate, also because of the effect that vertical force changes have on the tire's lateral displacement. Therefore, lateral displacement of the tire is used as a parameter to estimate the vertical force. due to the importance of computer modeling, finite element of the passengar Radial tire 175/80R14 has been used. First lateral acceleration is taken, then with the double integration of the lateral acceleration, the lateral displacement of the tire is achieved.The influence of parameters such as pressure, velocity, vertical force, slip angle and friction coefficient on the tire's lateral displacement is investigated and then the slip angle, lateral force and friction coefficient are estimated. Estimation of slip angle and lateral force in the range of 0.1 to 5 degrees for 50 points at different velocities, pressures, vertical forces and friction coefficients and estimation of friction coefficient in the range of 0.3 to 1 at different speeds, pressures, vertical forces and slip angles are done. Finally, using the brush model in the cornering, the vertical force applied to the tire is also estimated. Vertical force estimation has been done in the range of 2.79 KN to 3.47 KN for 5 points, which is a very accurate estimate. Also, this algorithm can also extrapolate with available data and make accurate estimates outside of this range, which also performs extrapolation for 5 points in 3/64 KN to 4/32 KN. It was found that the maximum deviation for the 10 vertical forces estimated with the results of Abaqus software is 0.17% and the minimum deviation is 0.049%.The importance of accurately measuring tire and road forces in the dynamics of the car's drive to increase safety, steering and driving.
