US 2002/0133264 A1 · Virtual reality system for creation of design models and generation of numerically controlled machining trajectories

Abstract

A system for using a virtual reality environment to create a design model and generate numerically controlled (NC) machining trajectories for use in fabrication of the model. The model is created in a virtual environment by carving a workpiece with one or more tools, each of which may have the geometry of a hand tool (e.g. a knife) or a machining tool (e.g. milling cutter). The selection and manipulation of virtual objects is performed in virtual space. Swept volumes of the virtual objects are generated using a solid modeling system according to the shape of the virtual objects and their trajectories, and Boolean operations are performed on the swept volumes and the initial virtual stock (workpiece) to create the design model. If the virtual object has the geometry of a computer numerical control (CNC) machining tool, the real NC machining trajectories for making the design object can be generated from the virtual object's movements, during the design model creation with the virtual reality environment. In order for the virtual object to simulate the real machining tool, constraints are applied on the movements of the user to represent the physical effects and limitations of the real machining process. The trajectories of the machining tool in the virtual reality environment are post-processed by computer software, which converts the user movement (position and orientation) of the virtual tool to NC trajectories after taking the user movement and the machine parameters and conditions into consideration.

Claims19

Dependent claims

A system that uses a virtual reality environment to create a design model and generate numerically controlled (NC) machining trajectories for use in fabrication of the model, said system comprising:

display means for displaying in real time the three-dimensional images of a virtual environment with virtual machines, tools, workpieces and objects;
manipulation means for navigating through the virtual environment, sizing the virtual objects, and changing the positions and orientations of the virtual objects;
tracking means for measuring the position and orientation of a user's hand;
sensing means for detecting touch or measuring force;
application means for applying a sense of touch or feedback force to the user;
communication means for allowing remote natural communication between multi-users participating in the design creation process;
and
computation means for creating said design models and generating said NC machining trajectories by obtaining inputs from said tracking means and said sensing means and generating outputs to said display means, said manipulation means, and said application means;
wherein
said system operates in its entirety in real time, and design parameters and machining parameters defined by the operation of said system are output for at least one of direct application to a manufacturing protocol and review by a designer.

7 more elements

A process for using a virtual reality environment to create a design model and to generate numerically controlled (NC) machining trajectories for use in fabrication of the design model, said process comprising the steps of:

(a) displaying a three-dimensional virtual environment in real time by a computer system;
(b) selecting a virtual workpiece created by a geometry modeler for placement in the virtual environment;
(c) selecting a virtual machine tool for use on the virtual workpiece;
(d) gripping the virtual tool by use of a haptic device;
(e) manipulating the virtual tool in the virtual environment to create a design model while the computer system records positions and orientations of the virtual tool and displays the condition of the virtual workpiece;
(f) simulating geometric changes of the virtual workpiece corresponding to the manipulation of the virtual tool;
(g) providing geometric information from the geometry modeler and material data of the virtual tool and the virtual workpiece as inputs to a physical simulation program;
(h) computing by the physical simulation program at least one physical attribute of the virtual tool selected from the group consisting of heat, cutting force, tool wear, tool vibration and breakage based on the inputs provided in step (g);
(i) transmitting the physical attribute data computed in step (h) to a user;
(j) generating an NC program from machine parameters, geometry of the virtual tool and position and orientation data of the virtual tool;
and
(k) providing the NC Program and geometric models of the virtual workpiece and virtual tool from the geometry modeler as inputs for fabrication of the real design model.

9 more elements

Dependencies are inferred from the claim text.

Virtual reality system for creation of design models and generation of numerically controlled machining trajectories

Life of this patent

Virtual reality system for creation of design models and generation of numerically controlled machining trajectories

Life of this patent

Abstract

Claims19