Hybrid MachineTool y Simulation ㈜ 캐즈테크 이병흠 과장 Contents 1. General Introduction to Machine Tool Simulation 2. MFBD Modeling of Machine Tool Parts 3. General Machine Tool Components 4. Cutting Force Implementation - Example g p p 5. Analysis Example 1
General Introduction to Machine Tool Simulation ❶ Improved insight into the system mechanics / control Simulate displacement, velocity, acceleration of each body Calculate reaction forces torque stresses everywhere in the struct Calculate reaction forces, torque, stresses everywhere in the struct ure “Slow Motion” of system functionality Parameter studies and optimization – “What if” studies General Introduction to Machine Tool Simulation ❷ Cost/Risk reduction through “Preventive Simulation” Traditionally the development of machine tools uses the try and error method based on prototyping and engineering experience p yp g g g p With the use of simulation the manufacturer has the possibility to make chang es on his virtual prototype very fast and without the cost generating step of ph ysical prototyping Due to this new concept of product development the Machine Tool manufactur e reduces the time to market and gets key benefits compared to its competitor s [SIEDL] 2
General Introduction to Machine Tool Simulation ❸ Trouble shooting Understanding reasons of system performance failures Upfront testing of different solution concepts Upfront testing of different solution concepts Parameter studies / sensitivity studies Example Chatter Vibrations - influenced by the dynamic machine tool behavior General Introduction to Machine Tool Simulation ❹ Special Requirements for Simulation Simulation requirements are very complex in nature Physical description are often extremely difficult; FEA vs MBD Physical description are often extremely difficult; FEA vs. MBD High precision of the simulation results necessary In most cases a simulation department does not exist The catalyst effect Initial additional efforts have to be accepted Uncertainties and risk management Effort/Benefit without VP Efforts Project Duration 3
General Introduction to Machine Tool Simulation ❺ Value generating by simulation Opportunities for machine tool manufactur ers: Testing of new and innovative concepts with reduced risk of system level failure High optimization potential due to param eter studies Identification of machine tool structural weak points early in the design phase Study interaction between machine stru cture and motion control engineering Improve machine precision and cutting power Product vision: Virtual commissioning of [BÜRGEL] a machine tool General Introduction to Machine Tool Simulation Historical Machine Tool Simulation (FEM & MKS) 4
General Introduction to Machine Tool Simulation Historical Machine Tool Simulation - Based on Finite Element Analysis (FEM) FEM only allows structural analysis o FEM only allows structural analysis o f machine tool behavior at discrete lo cations But machine tool behavior is much m ore than only structural behavior ther efor critical quality aspects are negle cted: Dynamic influences Dynamic influences Non linear behavior Controller feedback [ÖRTLI] General Introduction to Machine Tool Simulation Historical Machine Tool Simulation - Based on Multi Body Simulation (MBS) Historicaly the multi body simulation of machine tool only builds up the rigid body movement forced by forces and constraints. This neglects the structural deformations out of the eigenvalue movements charged of external forces [WECK] 5
General Introduction to Machine Tool Simulation Historical Machine Tool Simulation - Changes Dynamics Statics 4 70 - 84 St Structural Analysis t l A l i Multi Rigid Body Dynamics Local Stress Analysis, System Level Design Linear FEA Part Level Design Flexible Body Dynamics Structural Dynamics 85 - 99 Linear, small deformation Large Deformation Modal synthesis technique, Non-Linear FEA Co-Simulation (Interface) System & Local Level Simulation System & Local Level Simulation Integrated Multi Physics 1 Integrated Multi Physics g y 00 - 1 Simulation (MBD, Linear & Simulation (MBD, Linear & Nonlinear FEA, CFD, Hydraulics, Nonlinear FEA, CFD, Hydraulics, Control, Electro & circuit, Control, Electro & circuit, Durability, etc.,) Durability, etc.,) MFBD (Multi-Flexible-Body Dynamics) General Introduction to Machine Tool Simulation Advantages of Multi Body Simulation in Machine Tool Development 6
General Introduction Agenda Advantages of integrated Multi Body Simulation in Machine Tool General Introduction Development Software Setup Simulation task: Complete system simulation of mechatronic systems MFBD Modeling RecurDyn Solution: General Components I Components I (Basic machine eleme Integrated simulation environment for nt) Multi-Body Dynamics, Finite - Eleme Cutting Force nt Analysis and Controls Driving Systems Integrated Graphical Analysis I Response Simulation User Interface Actuation I Integrated Multi- Discipline Expression Dynamics Solver (IMD) Actuation II CoLink RecurDyn FEMBD: Hybrid Modeling Post Processing / Val Post Processing / Val M d l Modal reduction (RFLEX) d ti (RFLEX) ue Generating Non - linear FEA (FFLEX) Future Developments of FBG Machine Tool RecurDyn Controls integration Co - Simulation Full integration with RD/Colink General Introduction to Machine Tool Simulation Advantages of integrated Multi Body Simulation in Machine Tool Development Machine Tool Components: Computerized Numerical Contr ol Programmable Logic Controlle r Electrical Components iMBD iMBD Mechanical Components FEM FEM Process Technology MFBD MBS [SIDL] 7
General Introduction to Machine Tool Simulation Applying flexibility to Multi Body Systems Vision: Enhanced representation of machine behavior at the system level by consideration of component elasticity consideration of component elasticity Increase the simulation accuracy by recording component deformations, mechanical resonances, … Integrated stress analysis based on dynamic loads Consideration of static and dynamic component deformations. Example: rocker arm Abb. Positionsfehler Abb. GeschwindigkeitsfehlerAbb. Beschleunigungsfehler General Introduction to Machine Tool Simulation Applying flexibility to Multi Body Systems Collection of machine resonances and natural oscillations due to periodic stimulation stimulation Cutting Force N f = 40 Hz 200 180 n 160 140 0,8 0,9 1 1,1 1,2 Zei t 8
General Introduction to Machine Tool Simulation Mechatronical Simulation Apart from structural effects the transient behavior of machine tool is highly affected by the numerical control systems. Fore example: the K v - Factor (speed/stroke gai n) Indicates the speed in which a particular positio n error is set to zero. The higher the K v the fast er the system but this also makes the system u stable… [BÜRGEL] General Introduction to Machine Tool Simulation Mechatronical Simulation … the simulation of the control system shows these effects easily. But only in … the simulation of the control system shows these effects easily. But only in combination with the structural/mechanical model the developer is able to see how this is affecting the machine tool behavior 9
General Introduction to Machine Tool Simulation Hybrid machine tool modeling The efficiency of machine tools is highly affected by several aspects. Common simulations (MBS – FEM – Control) have to be combined to validate the transient ( ) behavior of machine tools correctly. Due to the cost in time, money and accuracy this combination requires greater focus on the system level each machine tool component has to be simulated in. discretization Workshop@: optimization General Introduction to Machine Tool Simulation Value generating by Machine Tool simulation - Examples 10
General Introduction to Machine Tool Simulation ❶ Circularity Tests (ISO 230 T2) Standard acceptance certificate for general machine tools The NC-Control pretends an ideal circular orbit for the die holder Circular movement by controller or spline Variations of the pretended and measured circle are relate d to typical machinery failure [WECK] General Introduction to Machine Tool Simulation ❶ Circularity tests (ISO 230 T2) (2) RecurDyn validation 11
General Introduction to Machine Tool Simulation ❷ Frequency response / impact analysis Through a targeted impact the structure will be stimulated to os cillate in a broadband spectrum cillate in a broadband spectrum Goal is to rebuild the characteristic function for the transfer behavior RecurDyn validation General Introduction to Machine Tool Simulation ❸ Chatter vibration Effected by the interaction of dynamic machine- and the dynamic cutting-behavior Stability calculated by Nyquist Criteria St bilit l l t d b N i t C it i With 12
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