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We studied the effect of steering dynamics on lateral dynamics for a 1.6 ton 4x4 sport utility vehicle (SUV) on deformable surfaces. The vehicle used for the outdoor tests was equipped with (1) a steering robot to apply repeatable steering wheel excitations and (2) a high-precision differential GPS (DGPS) system to gather physical measures that describe lateral dynamics: lateral acceleration, yaw rate, and vehicle sideslip angle. The vehicle was driven over three different deformable surfaces~a loess and a sandy soil and wet snow~with a constant speed of 10 km/h. The steering robot applied inputs of (1) sine wave excitation at 0.5, 1.0, and 2.5 Hz, and (2) ramp change (or trapezoidal) excitation with steering wheel rate at 100, 500, and 1500 deg/s. Results are presented as frequency paths and time courses to analyze effects of surface and steering dynamics.

The paper presents an algorithm of idle speed control of the spark ignition automotive engine by means of spark advance control. The control algorithm is based on a neural network model of the effective torque. The additional load is estimated as effective torque less brake torque on the basis of a linear quadratic model. The additional load is understood as the sum of the alternator brake torque and the momentary and/or permanent changes of the engine's characteristics. The additional load value estimated, the required value of angular acceleration can be determined to make the engine return to the specified speed. This acceleration is achieved by adjusting spark advance. The required value of spark advance is estimated on the basis of the neural network model converse to that of the effective torque. The algorithm was experimentally compared with PID and adaptive algorithms in the same test bed. The tests were conducted under sudden change of external load.

The paper investigates the cylinder liner wear and its influence on the engine blowby. The course of cylinder liner wear was established on the basis of investigation, which was carried out using 5 diesel engines during long-lasting operation in motor trucks. Cylinder diameters were periodically measured in two perpendicular planes at four depths of the liner. During service of the trucks the blowby rate was also measured, which enabled evaluating of the changes of the blowby rate as a function of truck mileage. The effect of cylinder wear on the blowby was also predicted with the use of a mathematical model of a gas flow through the ring pack. The results of the numerical simulations and empirical investigations are compared and discussed.

It is required that engine control algorithms provide stable work of the engine regardless of the variability of loads, working conditions and the engine itself. The paper presents an improved method and the algorithm of idle speed control of the spark ignition automotive engine by means of by-pass valve position control. The proposed competitive adaptation algorithm comprises 3 adaptive algorithms of which the most suitable in particular conditions is selected automatically. The competitive adaptation controller was tested and compared with an industrially used PID and a single adaptive controller in idle speed under sudden external load. It proved to be better in terms of control error.

The paper describes a hybrid air-fuel mixture control system that uses neural network and the direct adaptive algorithm. The A/F ratio stabilization to the stoichiometric value is required to obtain maximum efficiency of the three-way catalytic converter operation. The issues of the algorithm synthesis of the adaptive control of the fuel injection have been formulated. This was supplemented by the presentation of the state-of-the-art in the adaptive control theory as applied to non-stationary random object identification. The control algorithms of the fuel injection have been reviewed and classified. The fuel injection algorithms in the SI engine have been described and differentiated in terms of the used engine model and regulator structure. The algorithms comprise elements of the object modeling as well as adaptive coefficients for the control quality of the air-fuel ratio in the steady and non-steady conditions.

The paper considers the effect of axial and radial clearances of compression rings in the piston grooves on the engine blowby. A mathematical model of piston-rings-cylinder seal, which integrates model of gas flow through the crevices of the RPC seal and model of rings motions in the grooves was used to predict the influence of particular clearances values on the blowby. The results of numerical calculations show that this influence is different for the top and second ring clearances and depends on engine operating conditions (especially rotational speed). The paper also presents some results of experimental research conducted to verify the model. The results of the experiment confirmed the results of the numerical predictions.