In this paper, dynamic and stability analysis of a flexible cam-follower system is investigated. Equation of motion is derived considering flexibility of the follower and camshaft. Viscous and Coulomb frictions are considered in the rocker arm pivot. The normalized equation of motion of the system is a 2nd- order differential equation with periodic coefficients. Floquet theory is employed to s...

The launch of the new 1.8 l TFSI engine marks the third generation of the successful four-cylinder gasoline engine family from Audi. It has been completely revised in order to meet ambitious CO2 targets and ensure compliance with future Euro 6 emissions standards. The new generation features numerous innovative technologies, including an exhaust gas cooling system integrated into the cylinder h...

Nowadays, downsizing is a major way to reduce fuel consumption and pollutant emissions of Spark Ignition (SI) engines. In downsized engines, new air path management systems such as turbocharging or Variable Camshaft Timing (VCT) are including, and an efficient control of the air actuators is required for engine torque control. Two non-linear estimators are proposed to estimate non-measured vari...

A considerable amount of research is currently being done on electromechanical valve (EMV) actuators as a potential replacement for the camshaft in order to achieve variable valve timing. Unfortunately, EMV actuators suffer from large impact velocities between the valve, valve seat, and the actuator itself resulting in excessive wear on the system and producing unacceptable levels of noise. Add...