The effectiveness of research on the basis of mathematical models (linear, nonlinear) describing the dynamics of bridge cranes and cargo oscillations during transitional modes of movement, increases significantly with the use of numerical methods and simulation models created by visual programming tools. Purpose. To develop and evaluate proposed simulation models of bridge crane dynamics. methodology. On the basis of wellknown mathematical models, simulation models of the "bridge crane (trol ley)-cargo on a flexible suspension" system are developed. The simulation models are created using the visual pro gramming tools of the SIMULINK application running on the MATLAB system. Simulink libraries and DSP System Toolbox components are used in the simulation. findings. Smodels of cargo oscillations during the bridge crane movement have been developed and adjusted. A comparative analysis of the proposed models has been performed. originality. With the help of SIMULINK visual programming tools for the first time we received a set of simula tion models of cargo oscillations during the transition modes of the bridge crane movement for linear and nonlinear formulation of the task. Practical value. The proposed smodels allow automating and visualizing studies of dynamics of bridge crane movement in order to determine their rational kinematic and dynamic characteristics. The models are provided with examples of calculation of dynamic motion modes.

Wheelset axles are essential parts of railway and mine site rolling stock. For fatigue testing of axles, various test-benches are designed to implement the cyclic loads. The effectiveness of test-bench vibration analysis grows with the use of numerical approach and simulation models created with the aid of visual programming tools. The purpose of the work is to develop and assess the proposed simulation models of test-bench dynamics created with the aid of visual programming tools. Based on mathematical models, the test-bench simulation models of the lever system vibration have been developed. Simulation models are created with the aid of Simulink visual programming tools running under Matlab system. For modelling the components of Simulink, the SimMechanics and DSP System Toolbox Libraries are used. The comparative analysis of proposed models has been made. For the first time, with the aid of Simulink visual programming tools, the set of test-bench vibration simulation models has been obtained in steady-state and transient motion modes for linear task formulation. The proposed S-models allow automation and visualization of the motion dynamics study for test-bench components in order to determine their rational elastic-weight, kinematic and dynamic behavior. Simulation of vibrations was carried out using design parameters of the test-bench metal framework.

The paper outlines the basic principles of constructing frequency diagrams and specifies the features of their application for the analysis of the dynamic state of the vehicle drive with cable traction on the example of a ropeway. To draw up the frequency diagrams, the ropeway traction circuit was presented as a dynamic system containing lumped masses and elements with distributed parameters. In this case, the moments of inertia of the rotating masses of the drive were brought to the traction pulley as a lumped mass. The traction cable segments are represented as elements with distributed parameters. The mathematical model describing the dynamic state of the drive consists of equations in the form of deformations of the traction cable segments using the positions of wave mechanics. Studies have shown that in most cases there is a fairly wide inter-resonance band, limited by the first and second eigenfrequencies. This phenomenon may be the basis for justifying the rational values of the rotational speed of the pulley as one of the kinematic parameters of the ropeway drive.

Practical value. The use of the received results and the formulated recommendations will allow designing ropeways with the lowered power consumption.

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