Mastercam problem, experts help!

!

Mechanical CAD/CAM Technology Experiment Instructions Unit: Department of Mechanical Manufacturing and Automation, School of Mechanical Engineering Experiment location: Mechanical CAD/CAM Laboratory Shandong University of Technology October 10, 2005 Experiment 1 Geometric modeling design of simple parts 1. Experiment purpose

Use CAD/CAM software, and be proficient in using AutoCAD2000 software to perform wireframe modeling, surface modeling, and solid modeling of simple parts.

2. Experimental content (based on AutoCAD2000 software) 1. Wireframe modeling of simple parts The wireframe model describes the framework of a three-dimensional object, consisting of points, lines and curves describing the object, and has no surface or body information.

(1) Use two-dimensional objects to create wireframe models. When drawing, use two-dimensional space to draw objects.

Move it to the appropriate position in three-dimensional space.

(2) Use straight lines and spline curves to create wireframe models. Users use the line command and spline command to create three-dimensional straight lines and three-dimensional spline curves. When creating, they must enter the coordinates (x, y, z) of three-dimensional space points.

(3) Use three-dimensional multi-line segments to create a wireframe model. Select "Draw → 3D Multi-line Segments" or start the three-dimensional multi-line segment drawing command on the 3DPOLY command line to draw a three-dimensional wireframe diagram. Finally, select the "Close" command.

2. Surface modeling of simple parts. The surface model not only contains the boundaries of the three-dimensional object, but also its surface features. The surface model under AutoCAD actually uses a plane grid to simulate the curved surface of the object. The more facets there are, the better the combination.

The closer it is to a curved surface.

The command to create a surface model can be used from the "Drawing" → "Surface" submenu or the "Surface" toolbar.

(1) Create a three-dimensional surface. Use the menu "Draw → Surface → Three-dimensional Surface" or the "3D" toolbar to create the basic surface objects provided by the system: cuboid surface, cone surface, lower hemisphere, upper hemisphere, grid, square pyramid

Surfaces, spheres, torus and wedge surfaces.

After selecting each option, the system will prompt the user to enter the corresponding parameters.

(2) Creating a surface of revolution mainly involves rotating the object around its axis to create a surface of revolution.

Use the menu "Draw → Surface → Surface of Revolution" or the command line "REVSURE" to create a surface of revolution, in which the path curve can be a straight line, a multi-line segment, a spline curve, a circular arc or an elliptical arc.

(3) Create a translation surface. Create a translation surface after translating the path curve along the direction vector.

Use the menu "Draw → Surface → Translate Surface", where the path curve can be a straight line, a multi-line segment, a spline, a circular arc or an elliptical arc.

The direction vector is used to specify the direction and length of the stretch, which can be a straight line or a non-closed multi-line segment.

(4) Create a ruled surface. Create a ruled surface between two objects using the menu "Draw → Surface → Ruled Surface". The user can use two different objects to define the boundaries of the ruled surface, such as straight lines, polygons, etc.

Line segments, splines, arcs or elliptical arcs, etc.

Both objects must be closed or open at the same time.

(5) Create a boundary surface and use 4 connected edges to interpolate to obtain the boundary surface.

Created using the menu "Draw → Surface → Boundary Surface", the user can select straight lines, multi-line segments, splines, arcs or elliptical arcs as edges.

These edges must be connected end to end to form a closed curve.

3. Solid modeling of simple parts. The solid modeling information is the most complete in the three-dimensional model. It not only describes the surface of the three-dimensional object, but also completely describes the volume characteristics of the three-dimensional object. Autocad provides basic three-dimensional voxels: cuboid, sphere,

Cylinder, cone, wedge, torus.

Use the union, intersection, and intersection operations between basic voxels to generate complex entities.

To establish an entity model, use the "Drawing → Entity" submenu or the "Entity" toolbar.

(1) Create basic voxels for creating basic voxels such as cuboid, sphere, cylinder, cone, wedge, and torus.

Use the menu "Draw → Solid → Cuboid/Sphere/Cylinder/Cone/Wedge/Torus" and other related commands, and follow the command line prompts to enter the corresponding data to create the corresponding solid shape.

(2) Create a rotating entity using the menu "Drawing → Entity → Rotation".

The rotated object must be a closed two-dimensional object, which can be a two-dimensional polyline segment, polygon, rectangle, circle or ellipse.

(3) Create combined entities. Users use the "Union", "Difference" and "Intersection" commands to create complex combined entities.