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The paper presents problems which occurred during a work of the student design team on a preliminary design of a light transport airplane. Some requirement considerations which provided a canard configured concept are presented. The main subject of the work are the problems referring to a preliminary aerodynamic concept and a preliminary configuration optimization of a canard configured aircraft of the considered class. In addition, some remarks on the research and design process are also presented.

Considerations are outlined about design aid for airframe shaping in small CAD systems. Authors discuss problems associated with the adaptation of existing programs. The particular solution: a simple 3-dimensional lofting extension of popular CAD system (Auto CAD) is presented. A brief description of its practical use in a composite glider fuselage designing and manufacturing is also included.

The authors measure and simulate the vehicle motion in situations where typical defensive maneuvers in road traffic are being carried out, namely straight braking, double lane-change (overtaking), and ramp input on the steering wheel. They reproduce the vehicle motion (i.e. velocity, vehicle's C.G. trajectory and yaw angle) by using real records or by the simulated electronic data recorder (EDR) outputs. Thus, they operate in a way that is similar to that employed by forensic experts who analyze the EDR outputs. The employed method provides means of comparing the real or simulated exact values of velocity and of the vehicle's C.G. trajectory to the readings obtained by integrating the EDR outputs simulation. Estimation of the error, produced by the expert employing the EDR outputs, can be made in this way. The results show a possibility of occurrence of significant values of the error for simplified version of the device.

The paper presents a driver model, which can be used in a computer simulation of a curved ride of a car. A computer simulation of the curved ride and directional control of the car plays a significant role in a study of vehicle active safety, as the cheapest and safest investigation method. An analysis based on an advanced dynamic vehicle model only is not satisfactory in many cases, when an interaction between the driver and the vehicle is not to neglect. The double lane change maneuver (ISO/TR 3888) is an example of the typical test procedure in which the vehicle-driver- environment model should be taken into consideration. In elaborated driver model it is assumed that the visual signal is most important for a directional control of the car. The driver model is described by three parameters: aim point distance, response delay and steering angle gain. The driver model can be used in studies of vehicle handling and stability when closed-loop procedures are needed.

Safety on roads strongly depends on appropriate illumination at the foreground of the running vehicle.The head lights projectors should provide good quality visibility of the road surface in normal atmospheric conditions. Unfortunatelly, they do not secure the sufficient quality in night fogs conditions which are inseparable element of our climatical conditions.The low beam lights and fog lights are the most often used typ of projectors in difficult atmospheric conditions. In the paper the results of light calculation and justification of applying the fog projectors as well as comparison of their lighting features in relation to the main low beams lights were presented.

The authors simulate the vehicle motion in situations where typical defensive maneuvers in road traffic are being carried out, namely straight braking, singular lane-change and “J-turn”. They reproduce the vehicle motion (i.e. velocity, vehicle's C.G. trajectory and yaw angle) by using the simulated “black box” outputs. Thus, they operate in a way that is similar to that employed by forensic experts who analyze the “black box” outputs. The employed simulation method provides means of comparing the simulated exact values of velocity and of the vehicle's C.G. trajectory to the readings obtained by integrating the “black box” outputs simulation. Estimation of the error produced by the expert employing the “black box” outputs can be made in this way. The body pitch and roll are sources of longitudinal and lateral acceleration recording errors because a gravitational acceleration component for the respective direction is added in simplified version of the device.

The paper presents a model derived for real time simulation. It has been applied in low-cost PC-based autoPW driving simulator built at the University of Technology, Faculty of Transportation, Poland. The following assumptions have been done: even, horizontal road surface, no vertical, pitch and roll vibrations of the body as well unsprung masses. The normal reactions of the road are described in quasi-static way. Compliances of steering system as well as description of six aerodynamic drag components are taken into account. The tire model is based on HSRI-UMTRI model with addition of aligning moment description. The model was experimentally verified.

Road transport sector is significant source of the air pollution in Poland. The total exhaust emission from particular vehicle is estimated as the total mass of the selected air pollutant released into the air during the vehicle’s trip. In the context of the thermodynamic conditions, the total exhaust emission can be split into two parts: hot emission, when the engine achieves the normal operating temperature, and cold-start emission - produced during the thermally unstable engine’s operating conditions. The aim of the paper is to present results of mathematical modelling of the influence of the fleet age structure used in Poland on the cold-start emissions which are released into the air shortly after the engine’s start. There are considered emissions from the passenger cars, and the light commercial vehicles.

The temperature influences significantly the braking effectiveness. The paper describes consistency criterions of the brake thermal state in road braking conditions and on the roll-stand. As a result of the vehicle motion simulation, the time histories of the heat fluxes generated on the friction surface of the front and rear disc were determined. They were used as an input data for the model of the heat transfer process in disc brakes. The problem was solved by the use of the finite element method. Time histories of temperatures on the friction surfaces and in the material of the disc were calculated. As a preliminary consistency criterion of the brake thermal state in road and roll-stand braking conditions, a balance of the energy cumulated in the brake rotor was assumed. As the most reliable consistency criterion an equality of average temperatures of the friction surface was assumed.

The article demonstrates selected issues related to assessment of computational accuracy in accident analysis. The hereto presented theoretical grounds of the methods make it possible to consider uncertainties in the assessment of input data values. The methods were compared on the basis of their exemplary application in the case of braking process study of a vehicle in rectilinear motion. Also for the aforementioned case, the results obtained by means of various computational methods of vehicle motion (analytical and simulation models) were compared with the outcome of the experimental study.

The paper briefly presents two simulation models which describe the motion and dynamics of biaxial vehicles: a medium class car and 12 tons truck. The road surface may be even or uneven. The main models may be divided into coupled submodels. Their equations of motion can be derived separately. The programs can be run even on personal computers. The models are experimentally verified on even roads for typical manoeuvres recommended by ISO. The paper shows mainly the results of experimental evaluation of simulation models. It also presents steering system submodel in more detail. Its combination with other submodels describe small car motion and dynamics including the influence of steering system freeplay and dry friction.