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Analogically, test results and results of the calculation using Eqs (2.18)–(2.19)and (2.37)–(2.41), considering gyroscopic forces, are presented in Fig. 2.14.a) b)0.60.3experiment w ithout damping with dampingexperiment w ithout damping w ith dampingVelocity mm/s0.50.4Velocity mm/s0.250.20.3test1 test2 test3 test4 test5 test60.15test1 test2 test3 test4 test5 test6Figure 2.14. Comparative analysis of experimental and theoretical results (dynamical modelwith two degrees of freedom) for horizontal (a) and vertical (b) vibrations bycutting2.7. Conclusions of Chapter 2Data flows at MU have first been investigated by direct measurement with a videomeasuring system.1. The main advantages of the digital video measuring system described aboverely on a relatively low cost, portability and extended possibilities of digitalimage analyses, e.g. exact measuring of surface areas, average wear landlenghts and perimeters. Automated measuring also excludes human mistakesand due to saved images permits to analyse all data later off-line, which isimportant when carrying out long-lasting non-repeatable machining tests.2. However, video measurement does not provide suitable results in industrialconditions due to excessive chip flows, use of a coolant, and changing lightingconditions. Measurements with a profilograph are time-consuming and difficultto automate. Therefore the received data can be used for development ofindirect monitoring models for estimating the influence of tool wear dynamicsby cutting forces, vibrations and noise measurement.3. Analysis of roughness measurements data confirmed the accuracy of thedynamical calculation model. Surface roughness parameters of the blank quitesatisfactorily agreed with the corresponding data of the theoreticalinvestigation.4. The calculation model with two degrees of freedom was used to analyse theinfluence of gyroscopic forces on surface roughness. The results of calculationwhen taking into account the damping forces correspond to the experimentalresults.5. Analogically the calculation results for the dynamical model with one degree offreedom and motion cutting force are in a good agreement with theexperimental results in comparison with the cutting force first model. Theresults of experimental and theoretical investigations show that the dynamicalmodel is adequate and can be used for control of a lathe making it possible toattain the surface quality requested with a single run.33