Thematische Bibliographien / Lobe diagrams

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Auswahl der wissenschaftlichen Literatur zum Thema „Lobe diagrams“

Autor: Grafiati

Veröffentlicht am 28. Juni 2021

Zuletzt aktualisiert am 1. Februar 2022

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Zeitschriftenartikel zum Thema "Lobe diagrams"

Harrison, A. J. L., und T. R. A. Pearce. „Prediction of lobe growth and decay in centreless grinding based on geometric considerations“. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 216, Nr. 9 (01.09.2002): 1201–16. http://dx.doi.org/10.1243/095440502760291763.

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The growth and decay of lobes during centreless grinding have been studied by previous researchers using physical tests, time-domain simulation and identification of the roots of the Laplace transform of the characteristic equation. In this paper, the authors have extended these latter two methods to generate complete stability diagrams encompassing the entire practical range of machine set-up angles. These diagrams indicate that by varying the set-up angles in a prescribed manner during grinding, rapid rounding of arbitrarily lobed components can be achieved. This is verified via time-domain simulation. Secondly, a novel and arguably more intuitive method of predicting the lobe growth and decay during centreless grinding is presented. The method considers the locations of the three points of contact between a lobed workpiece and the regulating wheel, the support plate and the grinding wheel. Axial symmetry is assumed. A unique circle can be drawn through these three points. The centre and radius of this circle vary continually as the workpiece rotates, in a manner dependent upon the workpiece's profile and the set-up angles. An above-average instantaneous radius leads, via machine stiffness, to a correspondingly larger grinding force and so to an increased instantaneous depth of cut. If this occurs when the trough of a lobe is being ground, the trough will become deeper and lobe growth will result. By contrast, if the instantaneous radius is below average when the trough is being ground, the lobe will decay. From this simple geometric consideration, the authors have calculated the rates of decay and growth of a range of numbers of lobes, across a wide range of set-up angles. The results are shown to agree well with those given using the previous methods.

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Abele, E., und U. Fiedler. „Creating Stability Lobe Diagrams during Milling“. CIRP Annals 53, Nr. 1 (2004): 309–12. http://dx.doi.org/10.1016/s0007-8506(07)60704-5.

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Dhupia, Jaspreet S., Bartosz Powalka, A. Galip Ulsoy und Reuven Katz. „Effect of a Nonlinear Joint on the Dynamic Performance of a Machine Tool“. Journal of Manufacturing Science and Engineering 129, Nr. 5 (17.04.2007): 943–50. http://dx.doi.org/10.1115/1.2752830.

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This paper presents the effect of experimentally evaluated nonlinearities in a machine joint on the overall machine tool dynamic performance using frequency response functions and stability lobe diagrams. Typical machine joints are very stiff and have weak nonlinearities. The experimental evaluation of the nonlinear joint parameters of a commercial translational guide has been discussed in Dhupia et al., 2007, J. Vibr. Control, accepted. Those results are used in the current paper to represent the connection between the column and the spindle of an idealized column-spindle machine structure. The goal is to isolate and understand the effects of such joints on the machine tool dynamic performance. The nonlinear receptance coupling approach is used to evaluate the frequency response function, which is then used to evaluate the stability lobe diagrams for an idealized machine structure. Despite the weak nonlinearities in the joint, significant shifts in the natural frequency and amplitudes at resonance can be observed at different forcing amplitudes. These changes in the structural dynamics, in turn, can lead to significant changes in the location of chatter stability lobes with respect to spindle speed. These variations in frequency response function and stability lobe diagram of machine tools due to nonlinearities in the structure are qualitatively verified by conducting impact hammer tests at different force amplitudes on a machine tool.

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Hayati, Sajad, Mohammad Hajaliakbari, Yalda Rajabi und Sajad Rasaee. „Chatter reduction in slender boring bar via a tunable holder with variable mass and stiffness“. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 232, Nr. 12 (01.03.2017): 2098–108. http://dx.doi.org/10.1177/0954405417690554.

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In this study, a new strategy is presented to increase the machining stability due to chatter suppression for boring and turning machining processes. The proposed approach is based on varying the position of stability lobes via changing mechanical properties of the tool body such as the mass and stiffness. Because of the shape of stability lobe diagrams, having a tool with a tunable stability lobe diagram can be useful to alter an unstable condition to a stable condition. For this purpose, a structure for the tool body is designed that is consisted of a hollow body with a core as a tunable screw inside it. As the core gets in or out, it changes the mass and stiffness of the tool body that leads to change the position of stability lobe diagram. In order to study the effect of designed structure on stability, the structure is simulated using a validated finite element time domain model. The time domain simulation shows a considerable improvement in stability of process. The strategy is experimentally applied to the process via modulation of the tool structure in the machining process to validate the simulation results. The experimental results have a high coincidence with theory and show a good improvement in stability.

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Friedrich, Jens, Jonas Torzewski und Alexander Verl. „Online Learning of Stability Lobe Diagrams in Milling“. Procedia CIRP 67 (2018): 278–83. http://dx.doi.org/10.1016/j.procir.2017.12.213.

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Wiseman, Richard, und Adrian M. Owen. „Turning the Other Lobe: Directional Biases in Brain Diagrams“. i-Perception 8, Nr. 3 (18.05.2017): 204166951770776. http://dx.doi.org/10.1177/2041669517707769.

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Past research shows that in drawn or photographic portraits, people are significantly more likely to be posed facing to their right than their left. We examined whether the same type of bias exists among sagittal images of the human brain. An exhaustive search of Google images using the term ‘brain sagittal view’ yielded 425 images of a left or right facing brain. The direction of each image was coded and revealed that 80% of the brains were right-facing. This bias was present in images that did not contain any representation of a human head. It is argued that the effect might be aesthetic in nature, the result of the Western tradition of reading left to right or due to the facial factors that underlie the bias previously found in portraits.

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Zhao, D., und Q. Zhang. „Regenerative Chatter Stability and Hopf Bifurcation Analysis in Milling System“. Advanced Materials Research 739 (August 2013): 400–407. http://dx.doi.org/10.4028/www.scientific.net/amr.739.400.

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The shifted Chebyshev polynomials and Floquet theory are both adopted for the prediction regenerative chatter stability and Hopf bifurcation in milling. The influences of the system parameter on the stability of the milling system have been analyzed. The stability lobe diagrams are obtained. The result shows that the shifted Chebyshev polynomials method is more accurate than the semi-discretion scheme for spindle speed lower than 3500 round per minutes. The stability in milling can well be predicted by the cutting depth and feed rate lobes diagrams. Only Hopf bifurcations are detected by the Eigen-value analysis. The stable solution transform from the stable equilibrium point to the quasi-periodic oscillation after Hopf bifurcation.

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Friedrich, Jens, Christoph Hinze, Anton Renner, Alexander Verl und Armin Lechler. „Estimation of stability lobe diagrams in milling with continuous learning algorithms“. Robotics and Computer-Integrated Manufacturing 43 (Februar 2017): 124–34. http://dx.doi.org/10.1016/j.rcim.2015.10.003.

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Löser, Michael, und Knut Großmann. „Influence of Parameter Uncertainties on the Computation of Stability Lobe Diagrams“. Procedia CIRP 46 (2016): 460–63. http://dx.doi.org/10.1016/j.procir.2016.04.031.

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Tyler, Christopher T., John Troutman und Tony L. Schmitz. „Radial depth of cut stability lobe diagrams with process damping effects“. Precision Engineering 40 (April 2015): 318–24. http://dx.doi.org/10.1016/j.precisioneng.2014.11.004.

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Dissertationen zum Thema "Lobe diagrams"

Sedlář, Jiří. „Konstrukce dvouosého suportu vícevřetenového soustružnického automatu“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-443158.

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This diploma thesis deals with the design of a two-axis multi-spindle lathe carriage. In the first part, there is made a research, and its aim is to find possible variants of design solutions. After the best rated variant was selected, the thesis further continues with the necessary technical calculations of the main design nodes such as a synchronous servomotor, ball screw, linear guide and bearing. The design itself was carried out with regard to calculations and the resulting model was examined in terms of dynamic stability. The subject of examination was to find the natural frequencies of the assembly and to determine the amplitudes of the oscillations which arise from the harmonic excitation force. Finally, Lobe diagrams for grooving and longitudinal turning operations were drawn.

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Montalban, Laura. „Evaluation of a Contactless Excitation and Response System (CERS) for process planning applications : An experimental study“. Thesis, KTH, Industriell produktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192679.

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Chatter vibration is a common problem for the manufacturing industry that limits the productivity, accuracy and surface quality of machined parts. This study is focused on the out of process methods, such as Stability Lobe Diagrams (SLD), that ensure the selection of the optimal cutting parameters in which the machining process is stable. Previous studies have found that the dynamic properties of the spindle change with the rotational speed. This fact can also affect the accuracy of the SLD predictions, since, the traditional structural dynamic tests such as the Experimental Modal Analysis (EMA) are carried out at static state. An alternative method for the calculation of speed - dependant SLD using a Contactless Excitation Response System (CERS) was proposed. The modal characteristics, such as natural frequencies and damping ratio were determined by EMA tests carried out at idle state whereas CERS measurements were performed at increasing rotational speeds up to 14000 rpm. Subsequently, the SLD at static and dynamic state were computed. Finally, it was concluded that there was not a significant variation of the dynamic properties and SLD prediction with spindle speed at the tested speed range (0 rev/min to 14000 rev/min).
Chatter är ett vanligt problem inom tillverkningsindustrin som begränsar produktiviteten och minskar noggrannheten och kvalitén på bearbetade ytor. Denna studie fokuserar på processkilda metoder, till exempel stabilitetsdiagram (SLD), vilka säkerställer valet av optimala skärparametrar för en stabil skärprocess. Tidigare studier har visat att spindelns dynamiska egenskaper är beroende av rotationshastigheten. Detta påverkar även noggrannheten vid skattningen av SLD eftersom traditionella strukturdynamiska tester, som experimentell modalanalys (EMA), utförs under statiskt tillstånd. En alternativ metod för bestämning av hastighetsberoende SLD med hjälp av ett beröringsfritt excitering- och svarssystem (CERS) föreslås. De modala egenskaperna, som till exempel egenfrekvens och dämpning, bestämdes med hjälp av EMA med stillastående spindel medan mätningar med CERS utfördes med ökad rotationshastighet upp till 14000 varv/min. Efter detta beräknades SLD för de båda fallen. Till sist drogs slutsatsen att testerna inte påvisade någon större skillnad, vare sig dynamiska egenskaper eller SLD skattning, för spindelhastigheter inom det testade intervallet (0 till 14000 varv/min).

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Quintana, i. Badosa Guillem. „Stability lobes diagram identification and surface roughness monitoring in milling processes“. Doctoral thesis, Universitat de Girona, 2010. http://hdl.handle.net/10803/7769.

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La millora de la productivitat i la qualitat són indubtablement dues de les principals exigències del sector productiu modern i factors clau per la competitivitat i la supervivència. Dins aquest sector,la fabricació per arrancada de material juga encara avui en dia un paper protagonista tot i l'aparició de noves tècniques de conformat per addició.Indústries com l'aeronàutica, l'automobilística,la del motlle o l'energètica, depenen en bona part de les prestacions de les màquines-eina. Aquesta Tesi aborda dos aspectes rellevants quan es tracta de millorar de la productivitat i la qualitat del sector productiu: el problema del fimbrament, més conegut per la denominació anglosaxona chatter,i la monitorització de la rugositat superficial en el mecanitzat a alta velocitat.
Productivity and quality improvement are undoubtedly two of the main demands of the
modern manufacturing sector and key factors for competitiveness and survival. Within this sector, material removal processes play, still nowadays, a principal role despite the emergence of additive manufacturing techniques. Industries such as aerospace, automotive, molds and dies or energy largely depend on machine tools performance for improved productivity and quality. This Thesis is focused on two important aspects when it comes to improving productivity and quality of the manufacturing sector: chatter problem, and surface roughness monitoring in high speed milling.

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Fiala, Zdeněk. „Vibrace při obrábění kovů“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229045.

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The diploma work deals with a mathematical description of vibration and its generation when machining. Moreover, some techniques of modal parameters measurement in the theoretical part are included. The practical part is designed and based on the measured natural frequencies of the machine with specific tool and materials. In conclusion, a lobe diagram stability for semiautomatic lathe SPN 12 CNC and selected machining operation is specified by means of apparatus.

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Juriga, Jakub. „Virtuální model části obráběcího stroje v ADAMS“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-230395.

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In theoretical part, this master´s thesis deals with vibrations in cutting machine and description of creation of self-excited vibrations theory. In practical part, there is problem of chatter in cutting machine solved with using simulation program Adams and computing program MATLAB. Gradually, Multi body system of cutting machine and model of cutting tool with features flexible body are analyzed. At the end all both models were used to create complex model of the cutting machine .

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Khandelwal, Avinash 1987. „The wiring diagram of antennal lobe and mapping a brain circuit that controls chemotaxis behavior in the Drosophila larva“. Doctoral thesis, Universitat Pompeu Fabra, 2017. http://hdl.handle.net/10803/663806.

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Drosophila larvae present unique opportunity for anatomical and functional mapping of their nervous system because of features such as numerical simplicity of neurons its nervous system is composed of, and ability to exhibit quantifiable behaviors such as chemotaxis. Here, we mapped entire antennal lobe of larval Drosophila with one of its circuits responsible for controlling sensorimotor transformation in lateral horn (LH) (higher brain) through a single brain descending neuron using electron microscopic 3D reconstruction. In antennal lobe, we reported a canonical circuit with uniglomerular projection neurons (uPNs), working to relay gain-controlled ORN activity to higher brain centers like Mushroom body and lateral horn. We also found a parallel circuit with multiglomerular projection neurons (mPNs) and hierarchically organized local neurons (LNs) selectively integrating signal from multiple ORNs at the first synapse with LN-LN connectivity putatively implementing gain control mechanism that can potentially switch from computing distinguished odor signals through panglomerular inhibition to allowing system to respond to faint aversive odor in an environment rich with strong appetitive odors. We also reconstructed and studied one of the olfactory connected circuits in the LH that was found to be influencing chemotaxis behavior in larva through a single brain descending neuron, PVM027. We found that this neuron was responsible in controlling stop response of chemotaxis behavior. EM reconstruction revealed its connection with variety of motor systems and SEZ descending neurons in the VNC. Connections were revealed with the peristaltic wave propagation circuit of larva, and PVM027 was found to be implementing stop by terminating and ceasing the origin of forward peristaltic waves.
Las larvas de Drosophila ofrecen una oportunidad única para el mapeo anatómico y funcional de su sistema nervioso debido a propiedades como la simplicidad numérica de neuronas que componen su sistema nervioso y su habilidad de exhibir comportamientos cuantificables como la quimiotaxis. En este estudio hemos mapeado el lóbulo antenal de la larva de Drosophila con uno de sus circuitos responsable de controlar la transformación sensorial-motora en el asta lateral (LH) (cerebro superior) a través de una sola neurona descendiente usando la reconstrucción 3D para microscopia electrónica. Hemos presentado, en el lóbulo antenal, un circuito canónico con proyecciones neuronales uniglomerulares (uPNs) responsables de transmitir aumentos controlados de actividad desde sus ORN* hasta centros superiores del cerebro como el cuerpo fungiforme y el asta lateral del protocerebro. Hemos descubierto también un circuito paralelo formado por neuronas con proyecciones multiglomerulares (mPNs) y neuronas locales (Lns), organizadas jerárquicamente, que integran selectivamente señales desde múltiples ORNs a nivel de primera sinapsis con conectividad LN-LN implementando aparentemente un mecanismo de aumento de control que potencialmente puede intercambiar señales olfativas distintas computacionalmente a través de inhibición panglomerular permitiendo al sistema responder a olores vagamente aversivos en un ambiente rico en fuertes olores apetitosos. También hemos reconstruido y estudiado uno de los circuitos olfativos que conectan con el LH conocido por influenciar la quimiotaxis de la larva a través de un sola neurona cerebral descendiente, la PVM027. Hemos descubierto que dicha neurona es la responsable de controlar la respuesta stop en el comportamiento de quimiotaxis. La reconstrucción por EM revela su conexión con una variedad de sistemas motores así como neuronas descendientes SEZ en el VNC. Observamos dichas conexiones gracias al circuito de propagación de onda peristáltica de la larva, y descubrimos que la PVM027 implementa la señal de stop terminando e interrumpiendo el origen de la onda peristáltica.

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Malý, Pavel. „Výpočtové modelování samobuzeného kmitání při obrábění“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-320178.

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Diplomová práce se zabývá analýzou produktivity a efektivity řezného procesu frézování. Pro zjištění kritické hloubky třísky byla analyzována reálná frézka. Model frézky byl vytvořen v programu Autodesk Inventor. Analýza řezného procesu probíhala v programu Ansys Workbench. Výsledky byly použity pro sestavení stabilitních diagramů. Po vyhodnocení výsledků byly navrženy dva přístupy pro zefektivnění procesu frézování. Vliv těchto změn na produktivitu řezného procesu byl ověřen porovnáním výsledků s předchozí analýzou.

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Sismilich, Vladimír. „Vibrace při obrábění kovů – příčiny a jejich eliminace“. Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229329.

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This diploma thesis is concerning about summarizing and describing types of vibrations, their causes and influences to the machining. The stable conditions of machining were pointed out. The experiment was conducted in which the frequency response function of specific milling machine was measured. Than the stability lobe diagram was constructed.

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Cvijetin, Mlađenović. „Dinamičko ponašanje obradnih sistema za mikroobradu“. Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=114858&source=NDLTD&language=en.

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Predmet istraživanja prikazanih u okviru doktorske diseracije su samopobudne vibracije pri obradi glodanjem. Na osnovu detaljne analize zakonitosti nastanka samopobudnih vibracija uspostavljena je određena paralela između glodanja i mikrogkodanja, za slučajeve kada je dubina rezanja veća od radijusa rezne ivice alata. Za tako usvojene pretpostavke, razvijeni su modeli unapređene numeričke simulacije procesa glodanja i mikroglodanja. Razvijeni modeli su svestrano verifikovani, s jedne strane, u segmentima gde postoje podaci u literaturi; poređenjem sa rezultatima drugih autora, a sa druge strane poređenjem sa sopstvenim eksperimentalnim ispitivanjima. Za eksperimentalno definisanje granične dubine rezanja pri glodanju predložena je inovativna metoda tangenti, a pri mikroglodanju, imajući u vidu raspoloživu mernu opremu, metoda hrapavosti obrađene površine. Matematički modeli i eksperimentalne metode su verifikovani pri obradi tri karakteristične vrste materijala i na dva obradna sistema pri glodanju, odnosno jednom materijalu i jednom obradnom sistemu pri mikroglodanju. Rezultati istraživanja su prezentovani kroz dvanaest poglavlja čiji sadržaj se navodi u nastavku.U prvom, uvodnom poglavlju, ukazano je na značaj istraživanja samopobudnih vibracija pri makro i mikroglodanju. Prikazana je i aktuelnost istraživanja analizom broja naučnih radova koji se bave problematikom samopobudnih vibracija u periodu od poslednjih dvadeset pet godina.Kroz drugo poglavlje detaljno su prikazana dosadašnja istraživanja samopobudnih vibracija pri makroglodanju, dok su u trećem poglavlju prikazana istraživanja samopobudnih vibracija pri mikroglodanju. Izvršena je analiza uticajnih parametri na graničnu dubinu rezanja, koja predstavlja osnovni pokazatelj dinamičke stabilnosti kako makro, tako i mikroobradnih sistema.Na osnovu saznanja prikazanih u okviru drugog i trećeg poglavlja u četvrtom poglavlju su definisani ciljevi i hipoteze istraživanja.Matematičke metode za definisanje karte stabilnosti obradnog sistema, prikazane su u petom poglavlju. Prikazana su dva matematička modela za definisanje karte stabilnosti pri makroglodanju, model srednjeg ugla kontakta alata u zahvatu i model Furijeovih redova. Prezentovana je numerička simulacija procesa obrade glodanjem, namenjena prvenstveno za simulaciju sila rezanja. Polazeći od prethodno prikazane ideje u okviru ovog poglavlja je razvijena nova matematička metoda predikcije granične dubine rezanja - unapređena numerička simulacija procesa glodanja.U okviru šestog poglavlja prikazane su eksperimentalne metode identifikacije vibracija mašina alatki, odnosno eksperimentalno određivanje modalnih parametara obradnih sistema kao i metode detekcije samopobudnih vibracija pri glodanju. U cilju definisanja granične dubine rezanja, prikazana je metoda frekventne analize vibracija pri glodanju, kao metoda koja se često koristi u savremenim eksperimentalnim istraživanjima. Međutim, i matematičke i eksperimentalne metode analize vibracija pri glodanju imaju određena ograničenja. Polazeći od prethodnog, razvijena je inovativna metoda tangenti, bazirana na ranije korišćenoj metodi u okviru Laboratorije za mašine alatke Instituta za proizvodno mašinstvo FTN u Novom Sadu, i primeni savremenih mernih sistema. Pored toga, u ovom poglavlju je eksperimentalno potvrđen uticaj samopobudnih vibracija na kvalitet obrađene površine i geometrijsku tačnost obratka.Metodologija sprezanja matematički i eksperimentalno definisanih funkcija frekventnog odziva elemenata mašine alatke prikazana je u sedmom poglavlju. Prezentovane su jednačine sprezanja pomerajnih odziva matematmički definisanih funkcija frekventnog odziva alata i držača alata, bazirane na Ojlerovoj teoriji grede, sa eksperimentalno definisanom funkcijom frekventnog odziva sklopa glavnog vretena mašine alatke.U okviru osmog poglavlja razvijen je matematički model sila rezanja pri mikroglodanju. Predloženi model sila rezanja, koji uzima u obzir silu trenja između leđne površine alata i obrađene površine, implementiran je u unapređenu numeričku simulaciju glodanja čime je omogućena njena primena za definisanje graničnih dubina rezanja pri mikroglodanju.Verifikacija razvijenih numeričkih i eksperimentalnih metoda za ispitivanje vibracija pri makroglodanju je prikazana u devetom poglavlju. Sproveden je niz eksperimentalnih ispitivanja, pri kojima su određivane granične dubine glodanja pri obradi tri različita materijala obratka (Al7075, 42CrMo4 i Ti-6Al-4V) na dva obradna sistema. Na osnovu ovih ispitivanjima izvršena je verifikacija unapređene numeričke simulacije glodanja i inovativne metode tangenti.U desetom poglavlju prikazana je verifikacija metoda analize samopobudnih vibracija pri mikroglodanju. Primenom metodologije sprezanja pomerajnih odziva, definisani su modalni parametri obradnog sistema za mikroobradu, potrebni za definisanje graničnih dubina rezanja, tj. karte stabilnosti, unapređenom numeričkom simulacijom mikroglodanja. Karta stabilnosti definisana razvijenom unapređenom numeričkom simulacijom, verifikovana je eksperimentalno i poređenjem sa literaturnim izvorima.U jedanaestom poglavlju data su zaključna razmatranja, kritički osvrt na ostvarene rezultate, i pravci budućih istraživanja.Dvanaesto poglavlje prikazuje pregled korišćene literature, koju čini 218 referenci većim delom citirane u samom radu, a u zasebnom poglavlju dati su prilozi.
The subject of research presented in the doctoral dissertation are self-excited vibrations in milling. Based on a detailed analysis of the self-excited vibrations occurrence, a certain parallel has been established between macro and micromilling, for cases when the depth of cut is greater than the cutting edge radius of the tool. For such adopted assumptions, models of advanced numerical simulation of macro and micromilling processes were developed. The developed models were comprehensively verified, on the one hand, by comparison with the results of other authors, and on the other hand by comparison with own experimental results. An innovative tangent method has been proposed for the experimental definition of the cutting depth limit in milling, and the method of machined surface roughness has been proposed for micromilling, having in mind the available measuring equipment. Mathematical models and experimental methods were verified by machining three characteristic types of materials on two machining systems in macromilling, and one material on one machining system in micromilling. The results of the research are presented through twelve chapters, the content of which is listed below.In the first, introductory chapter, the importance of the research of self - excited vibrations in macro and micromilling is pointed out. The topicality of the research is also presented by analyzing the number of scientific papers dealing with the issue of self - excited vibrations in the period of the last twenty - five years.The second chapter presents in detail the previous research on self-excited vibrations during macromilling, while the third chapter presents research on self-excited vibrations during micromilling. An analysis of the influential parameters on the cutting depth limit was performed, which is a basic indicator of the dynamic stability of both macro and micromachining systems.Based on the findings presented in the second and third chapters, the fourth chapter defines the goals and hypotheses of the research.Mathematical methods for defining the stability lobe diagram of the machining system are presented in the fifth chapter. Two mathematical models for defining the stability lobe diagram for macromachining are presented, the model of the tool’s mean contact angle and the model of Fourier series. Numerical simulation of the milling process is presented, intended primarily for the simulation of cutting forces. Starting from the previously presented idea, a new mathematical method for predicting the cutting depth limit has been developed within this chapter - an improved numerical simulation of the milling process.In the sixth chapter, experimental methods of machine tools vibration identification are presented, ie experimental determination of machining systems modal parameters as well as methods of self - excited vibrations detection during milling. In order to define the cutting depth limit, the method of vibrations frequency analysis during milling is presented, as a method that is often used in modern experimental research. However, both mathematical and experimental methods of milling vibration analysis have certain limitations. Starting from the previous one, an innovative tangent method was developed, based on the previously developed method, used within the Laboratory for Machine Tools, Institute of Production Engineering Facultz of Technical Sciences in Novi Sad, and the application of modern measuring systems. In addition, in this chapter, the influence of self - excited vibrations on the machined surface quality and the geometric accuracy of the workpiece is experimentally confirmed.The methodology of machine tool elements mathematically and experimentally defined frequency response functions coupling is presented in the seventh chapter. The displacement responses coupling equations of mathematically defined tools and tool holders FRF's (based on Euler 's beam theory) with the experimentally defined FRF of the machine tool main spindle assembly are presented.Within the eighth chapter, a mathematical model of cutting forces in micromilling was developed. The proposed cutting forces model, which takes into account the friction force between the reliefe tool surface and the machined surface, is implemented in an advanced numerical micromilling simulation, which enables its application to define cutting depth limit in micromilling.Verification of the developed numerical and experimental methods for vibrations analysis during macromachining is presented in the ninth chapter. A series of experimental tests were performed, during which the cutting depth limits were determined during the milling of three different workpiece materials (Al7075, 42CrMo4 and Ti-6Al-4V) on two machining systems.In the tenth chapter, the verification of the methods of analysis of self-excited vibrations during micromilling is presented. Using the methodology of coupling displacement responses, the modal parameters of the machining system for micromachining are defined, needed to define the cutting depth limits, ie. stability lobe diagram, by advanced numerical micromilling simulation The stability lobe diagram, defined by the developed advanced numerical simulation, was verified experimentally and by comparison with literature sources.The eleventh chapter provides concluding remarks, a critical review of the achieved results, and directions for future research.The twelfth chapter presents an overview of the used literature, which consists of 218 references, mostly cited in the paper itself.

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Martin, Denis. „Le dipole imprime alimente par couplage electromagnetique a une ligne microruban : synthese et realisation de reseaux a lobes de rayonnement formes“. Rennes, INSA, 1988. http://www.theses.fr/1988ISAR0004.

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Cette these decrit la synthese de reseaux lineaires de dipoles couples electromagnetiquement (dipoles c. E. M. ) avec prise en compte des couplages. Cette synthese est ensuite appliquee a la realisation d'un diagramme de rayonnement forme du type depression spherique

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Bücher zum Thema "Lobe diagrams"

Zenn diagram. Toronto, Ontario: Kids Can Press, 2017.

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Cody, Westphal, Hrsg. I love charts: The book. Naperville, IL: Sourcebooks, 2012.

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Négrier, Patrick. Temple de Salomon et diagrammes symboliques: Iconographie des tableaux de loge et de cabinet de réflexion. Groslay: Editions Ivoire-Clair, 2004.

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Zenn Diagram. Kids Can Press, Limited, 2018.

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Osgood, Libby, Gayla Cameron und Emma Christensen. Engineering Mechanics: Statics. University of Prince Edward Island, 2021. http://dx.doi.org/10.32393/engnmech.

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Introduction to engineering mechanics: statics, when acceleration is 0. Concepts include: particles and rigid body equilibrium equations, distributed loads, shear and moment diagrams, trusses, method of joints and sections, & inertia. This book is intended for those who love to learn.

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Mays, J. C. C. Contemplation in Coleridge’s Poetry. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198799511.003.0002.

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Chapter 1 follows the ascent from the technical understanding of a poem and its processes toward a sense of ‘spiritual contemplation’. Slow-reading a short Coleridge poem, ‘First Advent of Love’, representing lifelong concerns, Mays describes the meditation involved in both reading and writing the poem. He contrasts such meditation with the different, analytical process involved in Coleridge’s prose writing. He reveals how in ‘First Advent’ feelings adjust through a web of sounds, images, and allusions (to neo-Platonic ideas about love mediated through Renaissance and contemporary German authors). Inquiry into what is most important in the poem involves the matter of how the poem works: a matter of ‘Understanding’. Mays then looks to higher, numinous qualities in the poem that go beyond the understanding, and are properly imaginative in terms of Coleridge’s diagram of the ‘Order of the Mental Powers’, mediating between ‘Understanding’ and ‘Reason’ in terms of enérgeia.

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Nakai, You. Reminded by the Instruments. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780190686765.001.0001.

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David Tudor (1926–1996) is remembered today in two guises: as an extraordinary pianist of postwar avant-garde music who worked closely with composers like John Cage and Karlheinz Stockhausen, influencing the development of graphic notation and indeterminacy; and as a spirited pioneer of live-electronic music who realized idiosyncratic performances based on the interaction of homemade modular instruments, inspiring an entire generation of musicians. However, the fact that Tudor himself did not talk or write much about what he was doing, combined with the esoteric nature of electronic circuits and schematics (for musicologists), has prevented any comprehensive approach to the entirety of his output which actually began with the organ and ended in visual art. As a result, Tudor has remained a puzzle of sorts in spite of his profound influence—perhaps a pertinent status for a figure who was known for his deep love of puzzles. This book sets out to solve the puzzle of David Tudor as a puzzle that David Tudor made, applying Tudor’s own methods for approaching other people’s materials to the unusually large number of materials that he himself left behind. Patching together instruments, circuits, sketches, notes, diagrams, recordings, receipts, letters, custom declaration forms, testimonies, and recollections like modular pieces of a giant puzzle, the narrative skips over the misleading binary of performer/composer to present a lively portrait of Tudor as a multi-instrumentalist who always realized his music from the nature of specific instruments.

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Buchteile zum Thema "Lobe diagrams"

Großmann, K., und M. Löser. „Synthesis of Stability Lobe Diagrams“. In Lecture Notes in Production Engineering, 225–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-32448-2_10.

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Kauffmann, Pierre, und Jean-Claude Spehner. „The construction of Delaunay diagrams by lob reduction“. In Discrete and Computational Geometry, 205–16. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/3-540-47738-1_19.

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Zhang, Mingkai, Xiaowei Tang, Rong Yan, Fangyu Peng, Chen Chen, Yuting Li und Haohao Zeng. „A Boundary Auto-Location Algorithm for the Prediction of Milling Stability Lobe Diagram“. In Intelligent Robotics and Applications, 299–308. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-97586-3_27.

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Eynian, Mahdi, Sunday Ogheneochuko Usino und Ana Esther Bonilla Hernández. „Studies on Surface Roughness in Stable and Unstable End-Milling“. In Advances in Transdisciplinary Engineering. IOS Press, 2020. http://dx.doi.org/10.3233/atde200184.

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Surface roughness is an important aspect of a machined piece and greatly influences its performance. This paper presents the surface roughness of end-milled aluminium plates in stable and unstable machining conditions at various spindle speed and depth of cuts machined with cylindrical end-mills. The surface roughness is measured using high-resolution surface replicas with a white light interferometry (WLI) microscope. The measurements of the end-milled floors show that the surface roughness as long as the cutting is performed in stable conditions is insensitive to the depth of cut or spindle speed. In contrast, within chattering conditions, which appear according to stability lobes, surface roughness values increase almost 100%. While at the valleys of the stability lobe diagram, there is a gradual increase in roughness, at the peaks of the stability lobe, the transition from the stable to unstable condition occurs with a sudden increase of the roughness values. In the study of down-milled walls, while the roughness increases with the depth of cut within both the stable and the chattering regions, the transition from the stable to chattering condition can lead to a much larger increase in the surface roughness. These results could be used for strategic selection of operation considering the needs of robustness and possible variation of dynamic parameters that can affect the position of the cutting conditions within the stability lobe diagrams.

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Baker, Peter S. „More Diagrams by Byrhtferth of Ramsey“. In Latin Learning and English Lore (Volumes I & II), herausgegeben von Katherine O'Brien O'Keeffe und Andy Orchard. Toronto: University of Toronto Press, 2005. http://dx.doi.org/10.3138/9781442676589-035.

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„Reducing Hospital Costs by Reducing Supply Waste“. In Lean Six Sigma for Optimal System Performance in Manufacturing and Service Organizations, 82–105. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-4062-5.ch004.

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Hospitals lose a large amount of money through waste as defined by lean. Processes have been in place many years at medical facilities and waste is often accepted as unavoidable in the rightful “patient first” mentality. The Plan, Do, Check, Act cycle is used for the control and continual improvement of the waste management process at the hospital where the study took place. By adapting and utilizing lean and statistical tools such as scatter diagrams, histograms, Pareto charts, fishbone diagrams, and control charts, waste can be identified and reduced or eliminated. The use of the statistical tools provides a visual presentation of the message that the team conveyed. They are especially useful to summarize the information that would normally require much time and effort to elucidate its complexity. Further, they provide a visual summation with still a great deal of details leading to increased satisfaction, efficiency, and creates competitive advantage.

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Ogawa, Yukiko. „Fact, Narrative, Visualization as Fiction, and Love“. In Computational and Cognitive Approaches to Narratology, 333–53. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-5225-0432-0.ch013.

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This chapter's subject matter is “The Land of Hope”, a Japanese film inspired by facts. The primary aim is to apply structural analysis of narrative, a method commonly used for natural language text, to film, which is an audiovisual text. This research will adopt methods for decomposing the film into component units and rules for linking them that are appropriate to the physical/representational characteristics of the medium, and propose a procedure for visualizing the narrative structure using a single diagram. The second aim is to sketch the aspects of narrative content that structural analyses – which only regard its formal aspects – overlook, supporting the argument with knowledge from film cognition research and by focusing on particular themes. This chapter's research deals with a practical simulation that analyzes a film's form and content with an integrated approach, and advocates the methodology that is applicable to any film in principle.

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„Corolla open out, one lobe and its stamen folded forward to show scales, g. Floral diagram, h. Branch with fruit. Drawn by Priscilla Fawcett. From Correll and Correll 1982.“ In Florida Ethnobotany, 759–64. CRC Press, 2004. http://dx.doi.org/10.1201/9780203491881-125.

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„(1) Stage 1: correct analysis of the constituent parts of the problem question (a) Identify the FACTS given—place on a tree diagram. (b) Identify the primary and secondary LEGAL ISSUES raised by the facts, available defences and doubts in the law. Place on a tree diagram of the issues. List the issues under the facts. (c) Consider the LAW THAT MAY APPLY. The first task is to read the question and determine the topic. The problem chosen is contract. In an examination the speed with which a problem question is narrowed to a topic and then to issues within that topic can be of exceptional importance since time is of the essence. (Part of the technique is having engaged in consistent study techniques so you are up to date in your course study and your revision if an examination is involved.) You should have a clear idea of the areas of doubt where currently the law is unclear, as often this is the area in which problem questions will be located. The first stage of analysis involves a combination of linguistic ability and legal knowledge. The problem question can be underlined and issues drawn out in a very simple first reading. This combination is demonstrated in Figure 8.2, below. The words that are the clues to the legal issues are boxed and arrows leading from these words begin to discuss the legal issues raised. There are two things to note in a problem question like this one that comes with two labelled parts (a) and (b). You must answer both parts unless instructed clearly that candidates are to answer either (a) or (b). Many students can fall here and assume there is a choice. Do not exercise a choice unless this is clearly given otherwise you could lose half of the marks going for the problem question. As can be seen a lot has been done to interrogate the question and divide it into its parts. It is important to break the question down into its constituent issues, so that the context of (a) and (b) can be appreciated. (2) Stage 2: begin to work on discrete aspects of the problem question What should also be apparent is that you need to have a view as to whether a contract has been concluded between Cedric and Dorothy, and if so when, before (a) or (b) can be answered. The issues to be considered can also be set out as a narrative. These are: (1) What is the effect of Cedric writing to Dorothy to offer to sell the coin? (2) What is the effect of Dorothy’s letter? (3) What is the effect of Cedric’s two suggested responses: (a) that he ignored Dorothy’s letter; (b) that he put a sticker on it saying sold but Dorothy did not collect it? It should by now be apparent it was not the first time that the issue revolved around whether there has in fact been a contract concluded. The answer to this is dependent upon whether an offer and an acceptance can be located, and if so where they stand.“ In Legal Method and Reasoning, 275. Routledge-Cavendish, 2012. http://dx.doi.org/10.4324/9781843145103-214.

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Konferenzberichte zum Thema "Lobe diagrams"

Friedrich, Jens, Henning Hartmann, Alexander Verl und Armin Lechler. „Continuous learning support vector machine to estimate stability lobe diagrams in milling“. In International FAIM Conference. DEStech Publications, Inc., 2014. http://dx.doi.org/10.14809/faim.2014.0641.

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Li, Weitao, Liping Wang und Guang Yu. „Time Domain Study on the Construction Mechanism of Milling Stability Lobe Diagrams With Multiple Modes“. In ASME 2021 16th International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/msec2021-60227.

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Abstract The stability lobe diagram (SLD) is an important expression way of milling stability prediction result. The SLD obtained by only selecting the most flexible mode fails to predict the chatter if the milling process is dominated by multiple modes. To reveal the relationship between the SLD with multiple modes and the SLDs corresponding to each single mode, this paper studies the construction mechanism of the SLD with multiple modes by using the time domain method. First, the milling dynamic model of the tool with multiple modes is established. Then, the numerical method based on the Newton-Cotes rules is used to solve the milling dynamic model with multiple modes whose solution is in the form of the SLD. It shows that the SLD with multiple modes can be approximated by using the lowest envelope of the SLDs corresponding to each single mode. Finally, two study cases are adopted to verify the construction mechanism of the SLD with multiple modes. To verify the correctness of the SLD with multiple modes, a series of milling tests are carried out. The experimental results agree with the simulation results, which means the proposed time domain method can reveal the construction mechanism of the SLD with multiple modes.

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Burns, Timothy J., und Tony L. Schmitz. „Receptance Coupling Study of Tool-Length Dependent Dynamic Absorber Effect“. In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-60081.

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The chatter-free material removal rate during high-speed machining of aluminum using long, slender endmills is limited by the cutting system dynamics, which changes with the tool length. Traditional stability-lobe diagrams that predict the maximum allowable chip width for a given spindle speed are determined using the tool point frequency response function. A brief review is given of a combined analytical and experimental method that uses receptance coupling substructure analysis (RCSA) for the rapid prediction of the tool-point frequency response as the tool length is varied. The basic idea of the method is to combine the measured direct displacement vs. force receptance (i.e., frequency response) at the free end of the spindle-holder system with analytical expressions for the tool receptances. The method is then used to provide an explanation for the dynamic absorber effect that has been observed in the context of tool-length tuning.

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Molnár, Tamás G., Tamás Insperger, S. John Hogan und Gábor Stépán. „Investigating Multiscale Phenomena in Machining: The Effect of Cutting-Force Distribution Along the Tool’s Rake Face on Process Stability“. In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-47165.

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Regenerative machine tool chatter is investigated in a nonlinear single-degree-of-freedom model of turning processes. The nonlinearity arises from the dependence of the cutting-force magnitude on the chip thickness. The cutting-force is modeled as the resultant of a force system distributed along the rake face of the tool. It introduces a distributed delay in the governing equations of the system in addition to the well-known regenerative delay, which is often referred to as the short regenerative effect. The corresponding stability lobe diagrams are depicted, and it is shown that a subcritical Hopf bifurcation occurs along the stability limits in the case of realistic cutting-force distributions. Due to the subcriticality a so-called unsafe zone exists near the stability limits, where the linearly stable cutting process becomes unstable to large perturbations. Based on center-manifold reduction and normal form calculations analytic formulas are obtained to estimate the size of the unsafe zone.

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Lehotzky, David, und Zoltan Dombovari. „Modeling and Stability of Milling Processes With Active Damping“. In ASME 2019 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/detc2019-97551.

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Abstract In the recent decade, active dampers have been introduced to machining for the avoidance of machine tool chatter in milling processes. The tuning strategy for most of these devices is based on models which do not account for the dynamics of control loop within the active dampers, hence neglect the dynamics of actuator and measuring device, and do not consider filtering. However, these simplified models might lead to inaccurate stability predictions which can deteriorate the performance of active dampers. In order to better approximate the real behavior of milling processes controlled by active dampers, this paper develops a new mathematical model which incorporates the dynamics of control loop within these devices. In particular, the inertial actuator is modeled as an electromagnetic proof-mass transducer, while the dynamics of piezoelectric accelerometer and finite-impulse-response filtering are also taken into account. By the computation of stability lobe diagrams, it is shown that, at low-frequency actuation and at high-speed milling, the consideration of control loop dynamics in active dampers can be essential.

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Landers, Robert G., und A. Galip Ulsoy. „Nonlinear Feed Effect in Machining Chatter Analysis“. In ASME 2007 International Manufacturing Science and Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/msec2007-31045.

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Regenerative chatter is a major limitation to the productivity and quality of machining operations due to the excessive rate of tool wear and scrap parts which are produced. Machining chatter analysis techniques examine the stability of the closed-loop model (force process and machine tool-part structure) of the machining operation to determine the stable process parameter space. Almost all chatter analysis techniques assume a linear force process and develop stability lobe diagrams (i.e., plots of the stable and unstable regions in the process parameter space) for a specific feed. It is well known that machining force processes inherently contain a nonlinear relationship between the force and the feed, which is typically described by a power law. In this paper, the linear chatter analysis technique developed by Budak and Altintas is extended to account for the force-feed nonlinearity. The analysis provides insight into the effect feed has on chatter in machining operations. Also, by directly including the force-feed nonlinearity in the chatter analysis, the need to calibrate the force process model at different feeds is alleviated. The analysis is developed for turning and face milling operations and is validated via time domain simulations for both operations and by experiments for a face milling operation. The analyses show excellent agreement with both the time domain simulations and the experiments. Further, several end milling experiments were conducted that illustrate the nonlinear effect feed has on chatter in machining operations.

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Noel, David, Mathieu Ritou, Sebastien Le Loch und Benoit Furet. „Bearings Influence on the Dynamic Behavior of HSM Spindle“. In ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/esda2012-82563.

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The aeronautic industry requires high speed and high power spindles to obtain high material removal rates during long rough milling operations. The weakness of HSM spindle is the bearings, although high precision hybrid ball bearings have been developed to achieve this critical application. Inadequate use of spindles inevitably leads to shortened lifetimes. Choosing the operating conditions is a required step before machining applications. It can be achieved through either experimental tests or numerical modeling that leads to stability lobe diagrams. Stability of cuts relies on the dynamic behavior of the spindle, which is particularly due to the eigenfrequencies of the tool-shaft assembly. The frequencies depend on bearing stiffness that can change under operating conditions. That is why the impact of cutting conditions and bearing parameters on its stiffness are studied in the paper. A five degrees of freedom model of angular ball bearing is briefly presented. A complete bearing model is introduced. The originality of the approach is the complete technological modeling, notably of the radial expansions of inner and outer rings of bearing. A non-linear expression is established from continuum mechanics model. The influence of geometry of bearing, operating conditions and design parameters of spindle on the bearing stiffness are established and analysed. Then, modal analyses of the tool-spindle assembly are carried out in relation to the varying bearing stiffness. Finally, significance of the approach is demonstrated through the analyses of Frequency Response Function.

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Catania, Giuseppe, und Nicolo` Mancinelli. „Experimental Chatter Modeling of Milling Operations“. In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41931.

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This study refers to the investigation on the critical operating condition occurring on high productivity milling machines, known as chatter. This phenomenon is generated by a self-excited vibration, associated with a loss of stability of the system, causing reduced productivity, poor surface finish and noise. This study consists of the theoretical and experimental modeling of machining chatter conditions, in order to develop a real-time monitoring system able to diagnose the occurrence of chatter in advance and to dynamically modify the cutting parameters for process optimization. A prototype NC 3-axis milling machine was ad hoc realized to accomplish this task. The machine was instrumented by a dynamometer table, and a series of accelerometer sensors were mounted in the proximity of the tool spindle and the workpiece. An analytical model was developed, taking into account the periodic cutting force arising during interrupted cutting operation in milling. The system dynamical behavior was described by means of a set of delay differential equations with periodic coefficients. The stability of this system was analyzed by the semi discretization approach based on the Floquet theory. Lobe stability charts were evaluated and associated with frequency diagrams. Two chatter types were analytically and experimentally detected: period-doubling bifurcations and secondary Hopf bifurcations. Measurement data were acquired and analyzed in the time and frequency domain. Several tests were conducted in a wide range of operating conditions, such as radial immersion, depth of cut and spindle speeds and using different tools. Results are reported showing agreement between the numerical analysis and the related experimental tests.

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Xu, Chao, Pingfa Feng, Dingwen Yu, Zhijun Wu und Jianfu Zhang. „Stability Prediction of Milling Process With Closed Machining System Dynamics With Flexible Thin-Walled Workpiece“. In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-51454.

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Despite recent advances and improvements in modeling and prediction of the dynamics of the machining process, an efficient machining process is limited due to chatter and instability of machining system. In fact, the machining system contains various kinds of joints, which cause difficulties in dynamics modeling, simulation and prediction. Moreover, the flexible support system results in large deformation and violent vibration of the workpiece when machining, and the thin-walled workpiece easily gives rise to the chatter of the machining system. Therefore, the dynamics of the flexible support system was considered to calculate stability lobe diagram in the modeling of milling process. The whole machining system was regarded as a closed loop composed by the machine tool structures, support, workpiece and machining process. In this paper, the receptance coupling (RC) method was introduced to predict the dynamics of the closed machining system. A milling process was taken for example to predict the chatter limitations using the dynamics of closed model. The mathematical model of the machining system (machine tool structures, spindle, holder and tool), together with the details of joint contacts, was given based on the RC method. The RC model was used to obtain the dynamics of the system, while receptance of the tool point was coupled. Based on the coupling model of the machining system, the depth limitations under different speeds were estimated for the technology parameter optimization in milling process. The response was considered to be the sum of the cutting point and the support system. The flexibility of the support system was considered to be the feedback of the cutting stiffness. By this means, the traditional model was modified to calculate the stability lobe diagram based on the dynamics of the spindle and support system. Furthermore, the milling experiment was carried out to verify the prediction results, and the dominant natural frequencies of receptance at tool point were obtained by modal testing to define the stability lobe diagram. It was found that the chatter results matched well with the stability lobes. It was concluded that the support system with poor stiffness might cause violent chatter especially when the workpiece was thin-walled. The cutting depth limitations of the flexible support system were lower than that of the rigid one. Moreover, this closed model of the machining system is appropriate for the chatter prediction of the flexible support system or thin-walled workpiece, so it is helpful for a better parameter optimization.

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Curry, Brandon, Henry M. Loope, Thomas V. Lowell, Hong Wang, Jason Thomason und Olivier J. Caron. „RECENT CHANGES TO THE TIME-DISTANCE DIAGRAM OF THE LAKE MICHIGAN LOBE (MICHIGAN SUBEPISODE, WISCONSIN EPISODE)“. In 50th Annual GSA North-Central Section Meeting. Geological Society of America, 2016. http://dx.doi.org/10.1130/abs/2016nc-275575.

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