## 1 Introduction  
In order to solve the problems of productivity and economic efficiency, as well as to achieve the precision of the gear, efficient machining methods have been developed. According to [1], machining is still the unsurpassed method of producing gears of all types and sizes with high accuracy. Numerous studies have been carried out regarding the machining of gears by the milling process and the effect on the geometry of the processed wheel [2, 3]. The rolling generating process is used to produce the most high-quality gears, taking into account the advantages in terms of productivity and profitability [4, 5]. Hobs are used for obtaining spur gears, spiral gears, and worm wheels. The FD320A milling machine is one of the most commonly used tool-machine used for gear machining.  
Some studies refer to the influence of cutting-edge preparation on the wear resistance of gear hobs on a five-axes milling machine (e.g., [6]). Other studies cover the design, modal analysis, and experimental tests of gearboxes already machined (e.g., [7]).  
Numerical and experimental investigations on the dynamics and stability of the system workpiece-tool associated with milling operations have been presented, too (e.g., [8, 9]). An analytical method for the computation of the cutting-edge geometry of a gear hob based on vector calculus and matrices in the tool-in-use reference system, useful in the optimization process, was reported in [10].  
Review papers of various models of the milling process were written to illustrate the wide range of applicability (e.g., [11]).  
Dynamic models of the milling process have been developed that consider the deformation of the cutting tool during machining and the dynamic compliances of the workpiece (e.g., [12]). Scientists have published numerous studies regarding the calculation of tool wear during the gear milling process, these being oriented in two directions, namely, the calculation of wear in individual positions based on the simulated chip geometry (e.g., [6; 13]) and the introduction of methods based on FEM (e.g., [14; 15]).  
The FEM can directly give the tool wear and its morphology, but it has not been commonly used to predict tool life due to the great simulation time (e.g., [2; 16]).  
There are different algorithms and software to simulate gear machining such as PATRAN/NASTRAN [11]; Hob3D--which can be used for the analysis of the chip formation and for the cutting force in the milling process [17; 18], and it can also be extended to other cutting processes based on the same principle, all the movements being transferred on the cutting edge [19; 20]; ANSYS [21]; AdvantEdge [15]; DEFORM [22]; FRS/MAT/FRSWEAR [23]; and SPARTAPro [24; 25].  
The present work is an extension of the papers [26; 27] and aims to realize a comparative study of the experimental data with those simulated by ANSYS software. Experimental determinations of the displacements and tool shaft torque moments, due to the vibrations during the machining, have been conducted; a computer-assisted method for determining the contact surfaces' displacements between a hob cutter and the workpiece was performed; for a particular situation with known technological parameters, the errors that occurred during the technological process and, implicitly, the machining accuracy, were determined [26; 27]. A dynamic simulation of the milling process with the finite element method was performed, and the values of deformation, strain, and stress over a period of time have been determined.