Classifications

• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F30/00—Computer-aided design [CAD]
  • G06F30/20—Design optimisation, verification or simulation
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06F—ELECTRIC DIGITAL DATA PROCESSING
  • G06F2111/00—Details relating to CAD techniques
  • G06F2111/10—Numerical modelling

Definitions

• the present invention relates to the field of software for simulating physical phenomena.
• the present invention relates more particularly to software for simulating stamping.
• a first embodiment includes minimizing the discontinuities generated by the discharge by determining a voltage increment of a sample point in the mesh of the metal sheet in accordance with an incremental theory of plasticity about deformation.
• a second embodiment includes modeling a pull rod as a plurality of non-linear elastic sources to minimize discontinuities in the elasticity force during discharge.
• a third embodiment includes the filtering of a relative velocity vector of at least one contact node with respect to the useful surface of the punch, so as to avoid oscillations of friction forces due to the change of direction of the relative velocity vector during stamping of the part.
• the prior art also knows, from American patent application US 5552995 (The Trustées of the Stevens Institute of Technology), a computer-based design system for designing a part, a tool for manufacturing the part and a process for manufacturing the room.
• the design system has a processor and memory.
• the memory stores patterns of functions, each pattern of function being a representation of a primitive object having a form and a function.
• Each function pattern is indexed by the function of the primitive object and includes a representation of the primitive geometric entity having the form of the primitive object.
• Each function pattern can include information relating to a tool for manufacturing the primitive object or to a process for manufacturing the primitive object.
• the design system also includes an input device for receiving a request to design the part. This request includes one or more predetermined function (s) that the part performs.
• a design core module executable by the processor, designs the part, the tool for manufacturing the part and the process for manufacturing the part by accessing the plurality of function patterns in the memory for locating one or more object (s) ) primitive (s) to perform the predetermined function (s).
• a stamping tool is provided for manipulating a model on a computer, including mechanisms to allow a user to define a stamping tool to create a stamping function of the model. Characteristics of the stamping tool can be defined in such a way so that the stamping tool can be reused without having to redefine its characteristics.
• the prior art also knows a solution for the design of a manufacturing process comprising stages of representation of a work piece as a plurality of triangular finite elements, of representation of stamping tools with mathematical equations which typically include cubic polynomials, simulating deformation of the workpiece by stamping tools with a finite element model, the finite element model being explicitly integrated.
• the method can be implemented by an apparatus which includes a memory device which stores a program comprising instructions readable by a computer, and a processor which executes the instructions.
• stamping simulation software of the prior art has the disadvantage of being limited for some as to the possibility of defining in a fine way the type of stamping process, and for others , more configurable, the disadvantage seen from the point of view of the end user, of being long and complex to implement taking into account the importance of the configuration.
• the present invention intends to remedy the drawbacks of the prior art by proposing a system which allows the user to define his own models. of a stamping process and which allows this same user or another, once a stamping process model defined, to no longer have to make only a limited number of settings for the process model stamping considered.
• Meta-models are defined to generate dialogs dedicated to the specific press of a given user.
• the invention relates in its most general sense to a method of numerically simulating a stamping process comprising the steps consisting in:
• the selection step modifies the state of the elementary constituents which are not relevant with regard to the constituents selected.
• the method comprises a step of loading from an external information medium at least part of the configuration information from the collection.
• the method comprises a step of loading from an external information medium of the blank model.
• the method includes a step of loading from an external information medium the digital representation of said subset.
• the step of constituting the specific collection is carried out via the display of a graphical interface and the recording of the information entered from said graphical interface.
• the step of displaying a graphical interface comprises an operation for personalizing a pre-recorded interface, this personalization taking into account at least in part the information coming from the previous stages of the process.
• several levels of use are defined, one of the levels of use, of supervision, requiring a common generic configuration defining in large part the stamping process concerned and the other levels of use, basic, not requiring more than a partial, complementary and specific configuration benefiting from the configuration previously carried out of the supervision level.
• FIG. 1 represents the progress of the process in accordance with the invention
• FIG. 2 represents the constitution and the processing of the meta-model in the form of a computer file
• Figure 3 shows the application as seen by the supervisor
• FIG. 4 shows the application as seen by the end user.
• stamping process includes tools and features.
• attribute means a physical and numerical characteristic. The deformation is often called “shaping” by one skilled in the art.
• the meta-model has the structure of a computer file, which constitutes a major part of the project. As described in Figure 2, this meta-model is constituted by the supervisor. The latter therefore partially completes the project, and leaves fields that the end user will fill in by means of a graphical interface. The set consisting of the meta-model and the data provided by the end user, thus constituting a complete project, is thus created and will be processed by the "solver".
• the supervisor chooses whether or not to let the end user fill in a given parameter. When a parameter is requested from the end user, a default value for this parameter is often provided by the supervisor.
• the object of the invention is to allow users to define most of the stamping modeling process themselves.
• the concept of macro-commands is divided into two distinct stages:
• the “supervisor” is the person who creates the graphical interface representing the macro-command, the steps, the process diagram, the tool groups, the attributes of the default process and the attributes that will be requested from the user. final (as shown in Figure 3).
• the “end user” is the person who uses the macro-command defined by the supervisor, by entering the following parameters (as shown in Figure 4): link between the groups and the mesh objects, parameters which can be modified for each drawing project (clamping force, drawing speed, friction ).
• the "group” is a specific type of object: blank, greenhouse blank, matrix, punch ...
• a group is defined by its representation in the diagram and by kinds of specific attributes directly accessible in the context of groups.
• a group corresponds to an object (a component of the press) seen by the end user.
• the attribute is the value corresponding to a property of a group (and therefore to objects) This can be a friction, a direction, a 2D curve ...
• a step is a period of time during which each object has a single kind of kinematics: movement, force.
• the entire simulation process should be divided into different stages, in accordance with the behavior of each group.
• Each group is active, or non-active, during each stage. If a group is not active during a step, its entities (nodes, elements, 3D curves) will not be taken into account by the solver during the processing of this step.
• a “parameter” is a value which is common to different groups and / or which can be requested from the user when he wishes to apply the macro-command. This can be a floating value (friction, thickness), a direction, a material property, an integer value (level of fineness, number of points), a 2D curve.
• a macro command must be created by a user called supervisor within the application.
• the supervisor does not need to load the project.
• a user loads a pre-process module of a project, he needs to prepare the objects and the meshes necessary for the process. He then accesses a button on the macro command toolbar, chooses the macro command he wishes to execute, sets the “end user parameters” proposed by the corresponding dialog box and clicks on the “ Apply »
• a graphic window is used to manage the creation, copying and deletion functions relating to macro-commands.
• First three frames (“blank”, “tools” and “parameters”) contain data that will be active during the entire processing: the material attributes of the blank, the list of groups corresponding to the tools (with group name, color , material and thickness) and the list of end user parameters.
• the list of parameters contains parameters which have two objectives: the first is, for the supervisor, to locate in a remote place a value which will be used by one or more attribute (s) of groups (for example tool / blank friction , common to all main tools). This simplifies changing this value.
• the second objective is to determine which parameters will be requested from the end user. These parameters can be: material properties, friction, thickness, drawing direction, speed curve ...
• stages The main frame (called "stages") allows attributes to be assigned to each group for each stage.
• buttons for managing the stages a button per stage updates the diagram, the active groups and the attributes.
• the supervisor can add, duplicate or remove steps.
• the diagram represents the relative positions of each group in function of each step. Its use makes it possible to show diagrams of the stages of the process, by representing the various tools, their kinematics and their state (active or not during the stage).
• a toolbox appears each time the macro command window is called up in supervisor mode. This toolbox includes four pages of the pattern for the stamping process: the “tools” page, the “blanks” page, the “behavior” page and the “post-process” page.
• the "blanks” and “tools” sections contain attributes that are common for all stages (group names and colors, material attributes).
• the stamping groups represent the content of the steps. Blank groups must have a real material attribute.

Landscapes

• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Theoretical Computer Science (AREA)
• General Physics & Mathematics (AREA)
• Geometry (AREA)
• General Engineering & Computer Science (AREA)
• Evolutionary Computation (AREA)
• Computer Hardware Design (AREA)
• Management, Administration, Business Operations System, And Electronic Commerce (AREA)
• Mounting, Exchange, And Manufacturing Of Dies (AREA)
• Shaping Metal By Deep-Drawing, Or The Like (AREA)
• Control Of Presses (AREA)
• Numerical Control (AREA)
• Processing Or Creating Images (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=32309919

Family Applications (1)

Country Status (9)

Families Citing this family (6)

Family Cites Families (16)

• 2002
  • 2002-12-02 FR FR0215157A patent/FR2847999B1/fr not_active Expired - Fee Related
• 2003
  • 2003-12-02 JP JP2004558160A patent/JP2006516932A/ja active Pending
  • 2003-12-02 CN CNA2003801094788A patent/CN101076804A/zh active Pending
  • 2003-12-02 AU AU2003298395A patent/AU2003298395A1/en not_active Abandoned
  • 2003-12-02 US US10/537,367 patent/US20060149523A1/en not_active Abandoned
  • 2003-12-02 KR KR1020057010022A patent/KR20050084119A/ko not_active Application Discontinuation
  • 2003-12-02 WO PCT/FR2003/003564 patent/WO2004053740A2/fr active Application Filing
  • 2003-12-02 EP EP03796141A patent/EP1576506A2/fr not_active Withdrawn
  • 2003-12-02 CA CA002508462A patent/CA2508462A1/fr not_active Abandoned

Non-Patent Citations (1)

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