Mining, construction, and other special vehicles for heavy use are designed to work under high‐performance and off‐road working conditions. The driving and executive mechanisms of the support structures and superstructures of these vehicles frequently operate under high loads. Such high loads place the equipment under constant risk of an accident and can jeopardize the dynamic stability of the machinery. An experimental investigation was conducted on a refuse collection vehicle. The aim of this research was to determine the working conditions of a real vehicle: the kinematics of the waste container, that is, a hydraulic rotate drum for waste collection; the dynamics of the load manipulator (superstructure); the vibrations of the vehicle mass; and the strain (stress) of the elements responsible for the supporting structure. For an examination of the force (weight) on the rear axle of a heavy vehicle, caused by its own weight and additional load, a universal measurement system is proposed. As a result of this investigation, we propose an alternative system for continuous vehicle weighing during waste collection while in motion, that is, an on‐board weighing system, and provide suggestions for measuring equipment designs.

The dynamic behaviour of large and complex structures largely depends on damping resistance in the structure. A portion of the structural energy is lost to deformations in material, friction between the contact surfaces, and relative motion within the structure. Often, in an analysis of numerical models, before the dynamic analysis of transient events (transient analysis), the damping resistance is adopted on the basis of recommendations, which implies an error of transient response (introduced by frequencies, logarithmic decrements and maximal amplitudes). Decreasing amortized vibratory movement is dependent on the extent of the structural damping. This paper presents the importance of structural damping in structural analysis and shows the experimental and theoretical procedure for identifying G values of the structural damping coefficient. A model for determining the G coefficient is shown in the example of a real tower crane structure. The experimentally obtained values were then used in the transient numerical FEM analysis, as the basis for adopting the conclusions about the dynamic behaviour of this class of structures (transportation machines). The effect of the external perturbation force of trapezoidal impulse form (lifting and quickly lowering of load) is introduced and the dynamic task, as an example of the use of the G coefficient G, is solved. The experimentally determined damping (theoretically isolated for tall truss structures) can be used in similar transient analyses.

Accidental actions caused by vibrations of supporting structures in mechanical systems represent the dynamic tasks of specific scientific and professional research in the field of human and equipment safety. This paper determines the mathematical model of physical excitation force created by   human power, based on the discrete-time Fourier transformation. For experimental verification of the model, we made a special platform for measuring bouncing force of people who create natural impulse oscillation. The paper shows the results of individual and group experimental testing of living force as the cause of accidents and dangerous effects on the structure. In the end, the excitation of the human operation of a malicious nature (heavy transport machine – crane) has been used to show the application of Fourier model to simulate one incident. For this purpose, the transient FEM analysis and the eigenvalues predetermined modal analysis are used. The paper is illustrated with photographs of experimental tests of dangerous human impulse in several working machines (objects).

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This paper presents the investigation of importancefor determining the dynamic structural response of heavy lifting machines subjected to extreme external effects. A measuring system for the experimental investigation of the dynamics of heavy lifting machines is proposed.It shows the experimental testing results of carrying structures for several classes of hoisting and an export mining machine. The results refer to the most important dynamic parameters. The dynamic parameters also include the duration of transient phenomena in handling lifting structures and structural damping.A technical solution based on the measuring chain that is integrated into the mining export plant information system was developed in the research. The recommendation to choose optimal measuring equipment for this kind of measurement is given to manufacturers and users on the basis of the experience gained in the design and implementation of specifi c measuring systems. The technical specifi cation of amplifi ers and transducers that should be developed for this kind of measurement is also proposed.