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Mate workflow If you make a lot of mates, it is important to have an efficient rhythm when working with the inter- face. The most efficient way to use the Mate interface is as follows: 1. Click the first entity. 2. Click the second entity. 3. Click OK on the RMB cursor icon, which is shown in Figure 13.2. FIGURE 13.2 The OK option on the RMB cursor Or, if the automatic default mate type is not the mate that you want to apply, then select it from the popup list, which is shown in Figure 13.3. FIGURE 13.3 The Mate selection popup list 4. Click the green check mark icon from the popup list. 5. Repeat steps 1 to 4. 6. After the last mate, press Esc, the green check mark icon, or the red X icon from either the PropertyManager or the confirmation corner in the upper-right corner of the graphics area. In SolidWorks 2007 sp0, there is a bug with the distance mate that has been fixed in sp1.0. In sp1.0, the distance mate defaults to the actual distance between the entities, but in sp0, it defaults to 1.000 inch, and so you must manually type in a distance. View and model positioning Sometimes you will have to rotate the model to achieve the correct view in order to select faces or edges. There are also times when you will want to pre-position so that the model snaps into the cor- rect position automatically. You can rotate individual parts in an assembly by dragging with the RMB. You rotate the view by dragging with the middle-mouse button, or MMB. You can move parts by dragging them with the left-mouse button, or LMB. You can pan the view by pressing Ctrl and dragging with the MMB. When you drag a part with the LMB while the Mate PropertyManager is active, SolidWorks does not add the selected entity to the Mate Selections list. CAUTION CAUTION 415 Getting More from Mates 13 20_080139 ch13.qxp 3/26/07 3:54 PM Page 415 To summarize these actions: n To rotate an individual component in an assembly, drag with the RMB. n To move an individual component in an assembly, drag with the LMB. n To rotate an assembly view, drag with the MMB. n To pan an assembly view, Ctrl-drag with the MMB. If you have a Spaceball or 3D motion controller, you can perform all of these actions more easily and simultaneously using one hand for view rotations and the other hand for selections. You can also use a Spaceball to move parts. Select Other The Select Other command enables you to select items that are hidden by other items. It is often used to select faces that are hidden behind other faces without rotating the part. You can apply the Select Other command through the RMB menu. Right-click where the face would be if you could see it. A list of entities displays, and you can select the entity you want from this list or from the graphics window. Moving your mouse over an entity in the list highlights the entity in the graphics window. Pressing Tab or scrolling the mouse wheel cycles through the entities one by one. Clicking faces with the RMB hides them, which allows you to see further down into the part or assembly. Clicking with the LMB either in the graphics window or the selection list box selects the item. Figure 13.4 shows the Select Other cursor and dialog box. FIGURE 13.4 The Select Other cursor and dialog box The item about to be selected turns red in the graphics window. Although this selection method is also used for other purposes, it is often used for selecting faces for mating. TIP TIP 416 Working with Assemblies Part III 20_080139 ch13.qxp 3/26/07 3:54 PM Page 416 Multiple Mate mode Multiple Mate mode enables you to select one face in order to mate multiple faces from other parts to it. Figure 13.5 shows the interface for this mode, which you can toggle to from the Mate PropertyManager interface. It also shows several small blocks being mated to a single large block. This function works only with the Standard Mate types, not with any of the Advanced Mates, which are discussed later in this chapter. FIGURE 13.5 The Multiple Mate Mode interface You can create a special folder for all of the multiple mates by selecting the Create Multi-mate Folder check box in the Mate Selections PropertyManager. You can also automatically link the val- ues for distance and angle mates with link values by selecting the Link Dimensions check box. SmartMates SmartMates are mates that you can create automatically by dragging one part onto the other with- out invoking the Mate command. There are three different methods that you can use to apply SmartMates: n Alt-dragging the part n Dragging the part from one window to another n Using Mate References Alt-dragging a SmartMate Probably the easiest way to quickly create a SmartMate is by Alt-dragging. One, two, or even three mates can be applied at once by holding down the Alt key while dragging a face or edge from one part onto a face or edge on another part. When you are dragging a part while pressing the Alt key, the part is made transparent to allow you to see other part faces that you may want to mate it to. A special cursor appears when a SmartMate is about to be applied. Figure 13.6 shows the cursors that appear for adding Concentric and Coincident mates. 417 Getting More from Mates 13 20_080139 ch13.qxp 3/26/07 3:54 PM Page 417 FIGURE 13.6 Applying a SmartMate When you drop the face onto the mating face to complete the mate, you must use the popup Mate toolbar to accept or alter the mate. In the examples in Figure 13.6, a face is being dragged onto another face. However, you can also drag edges and vertices. Mates are limited to being either Coincident or Concentric. The peg-in-hole mate is actually both a Concentric mate and a Coincident mate. This is the type of mate that is created between a screw and a hole, and is the result of Alt-dragging a circular edge onto a circular edge. When the circular edges are created by the intersection of a cylindrical face and a flat face, the Concentric mate goes between the two cylindrical faces, and the Coincident mate goes between the flat faces. The peg-in-hole mate is illustrated in Figure 13.7. The image to the left shows the state of the parts before the SmartMate. The image in the middle shows the SmartMate orienting the part in the wrong way so that the two parts interfere. In the image on the right, the part to which the SmartMate is applied has been reoriented by pressing Tab before the SmartMate is accepted by dropping the part. You can use the Tab key to flip the alignment if a SmartMate tries to put parts together in the wrong way. If you are in the process of Alt-dragging, make sure to release the Alt key before pressing Tab. The Alt-Tab combination shows a list of open applications. TIP TIP 418 Working with Assemblies Part III 20_080139 ch13.qxp 3/26/07 3:54 PM Page 418 FIGURE 13.7 Using SmartMate to create the peg-in-hole mate combination Drag between windows You can apply SmartMates when dragging a part from one document window to another, or when copying a part within a single window by Ctrl-dragging. The best way to drag a part from one win- dow into another is to tile the windows using the Tile command in the Window menu. Then drag the part using the face or edge that you would like to mate, and bring it near to the face in the assembly to which you want to mate it. The transparent preview should snap into place. Again, if it is backwards, you can just press Tab. The same is true when copying a part in the graphics window of an assembly. You can simply Ctrl- drag a face of the part to the face of the new location. Alt-drag this edge 419 Getting More from Mates 13 20_080139 ch13.qxp 3/26/07 3:54 PM Page 419 Mate references Mate references are model faces, edges, or vertices that are pre-selected and used in a SmartMate- like fashion when dragging a part in from Windows Explorer or from a library window. Mate References are discussed in Chapter 19 in the course of discussing library parts. Mating with macros If all of the confirmations and extra mouse-clicks to open and close windows are not for you, and you are just applying simple mates, then you may want to use macros to mate parts. Macros are not going to give you the same flexibility, but they do improve speed. However, you have to have the parts ready to go when you press the macro button, or you will create the wrong mate. You can find macros for Coincident, Concentric, Parallel, Perpendicular, and Tangent mates on the CD-ROM. For example, to use the concentric macro, you would need to pre-position the parts so that they are within 90 degrees of the proper alignment, have one of the parts mated in place such that that only one part will move, select the two cylindrical faces, and then run the macro. Macros are discussed in depth in Chapter 32. To run the macro, pre-position the parts, pre-select the faces, click Tools ➪ Macro ➪ Run, and then browse to the macro. Chapter 32 shows you how to connect macros to hotkeys, which makes this process easier. Like SmartMates, macros work best for the simpler mate types where you do not need to select any options. Mating for Motion Dynamic Assembly Motion is a powerful tool for visualizing the motion of mechanisms in SolidWorks. It works best if there is a single open degree of freedom. Degree-Of-Freedom analysis When working with motion in SolidWorks, you need to be comfortable with degrees of freedom. When inserted into an assembly, each model has six degrees of freedom: n Translation in X (tX) n Translation in Y (tY) n Translation in Z (tZ) n Rotation about X (rX) n Rotation about Y (rY) n Rotation about Z (rZ) CROSS-REF CROSS-REF 420 Working with Assemblies Part III 20_080139 ch13.qxp 3/26/07 3:54 PM Page 420 When applying mates, and especially when troubleshooting motion or overdefinition problems, it is important to look at how each mate translates into degrees of freedom being tied down. For example, a Coincident mate, planar face to planar face, ties down one translation degree of free- dom (in the direction perpendicular to the faces), and two rotational degrees of freedom (about directions which lie in the plane of the faces). What remains are two translational degrees of free- dom in the plane of the faces and one rotational degree of freedom about an axis perpendicular to the planar faces. A point-to-point Coincident mate ties down three translational degrees of freedom, and the part can only rotate. An edge-to-edge Coincident mate ties down two translational and two rotational degrees of free- dom. As a result, a part that you mate in this way can only slide along the mated edge and rotate around the mated edge. When using face-to-face Coincident mates, it takes three mates to fully define a block type part. When using edge-to-edge Coincident mates, it only takes two mates. You should read through the section on Summary of Mate Best Practices before adopting this approach. Something to be careful about is that a degree-of-freedom analysis frequently predicts an over- defined mate scenario when SolidWorks does not in fact display any errors or warnings. For exam- ple, if one block is mated to another with the simple case of three face-to-face Coincident mates, and each Coincident mate ties down one translational and two rotational degrees of freedom, then the part would be over-constrained by three rotational degrees of freedom. This may be an overly cautious approach, but it can mean the difference between an assembly that works and one where errors are frustratingly persistent. If you are careful to approach all parts with the degree-of-freedom analysis in mind such that any newly added mate does not duplicate any of the degrees of freedom that are already tied down, then you will have fewer assembly mate errors and fewer problems with assembly motion. This means that instead of the traditional three face-to-face Coincident mates, you would have one face-to-face Coincident (one translational degree of freedom, two rotational degrees of freedom), one edge-to-face Coincident (one translational degree of freedom, one rotational degree of freedom) and one point-to-face Coincident (one translational degree of freedom). This accounts for three transla- tional and three rotational degrees of freedom without overdefining any of them. It is true that SolidWorks internally compensates for over-defined degrees of freedom, but relying on it to do so and then tempting fate by methodically over-defining all assemblies is a risk that you do not have to take, even though it is common practice. Best bet for motion The best bet for creating motion in a SolidWorks assembly is to leave open a single degree of free- dom. This means that there is only one way the part can move, back and forth, either translation or rotation. Computers in general do not respond well to ambiguity. Dragging an item that may move in several ways is more likely to cause jerky or hesitant motion. BEST PRACTICE BEST PRACTICE TIP TIP 421 Getting More from Mates 13 20_080139 ch13.qxp 3/26/07 3:54 PM Page 421 A good example of this kind of problem with motion can be found in one of the sample assemblies that installed with SolidWorks 2007. I have included this example on the CD-ROM for your con- venience, and it is shown in Figure 13.8. The filename for the assembly is Plunger.sldasm. FIGURE 13.8 An assembly displaying best bet for motion If you drag the assembly parts from the locations shown in Figure 13.8, the performance varies. This is because when you drag the handle parts, for every position of the handle, there is only one solution for the rest of the parts. However, when dragging the plunger bar, for every position of the plunger bar there are two possible positions for both the links and the handle. This kind of ambi- guity causes problems in SolidWorks assemblies such as assemblies that have open degrees of free- dom but will not move or move in a jerky fashion. Another example of difficulties related to open degrees of freedom and motion is shown in Figure 13.9. The grippers at the end of the arm move when the rest of the arm moves, but the grippers cannot be independently controlled. To fix this problem, you may want to either use the Fix/Float option (available through the RMB menu), or use configurations with mates suppressed or unsup- pressed. You can open this assembly from the CD-ROM, in the filename called Chapter 13 Robot Assembly.sldasm. Drag here and the motion is poor Drag here and the motion is smooth 422 Working with Assemblies Part III 20_080139 ch13.qxp 3/26/07 3:54 PM Page 422 FIGURE 13.9 A robot arm assembly with degree-of-freedom conflicts Working with Advanced Mate Types Advanced mate types greatly expand the number of ways that you can put parts together into assemblies. Advanced mate types include the following: n Symmetric n Cam n Width n Gear n Rack and Pinion n Limit n Belts and Chains 423 Getting More from Mates 13 20_080139 ch13.qxp 3/26/07 3:54 PM Page 423 Symmetric mate The Symmetric mate works a lot like the Symmetry relation in sketches, except that a plane is used as the plane of symmetry instead of a construction line. Figure 13.10 shows a Symmetric mate being applied to the gripper jaws. The Symmetric mate is listed in the Advanced Mates pane of the Mate PropertyManager. FIGURE 13.10 Applying a Symmetric mate Cam mate The Cam mate creates a special instance of either the Coincident or Tangent mate. Four conditions exist with the Cam mate: n Coincident: Vertex on the follower mated to a cam that is created from a single closed- loop face (spline, circle, ellipse). n Tangent: Cylindrical or planar face mated to a cam that is created from a single closed- loop face. n CamMateCoincident: Vertex on the follower mated to a cam that is created from multi- ple faces. This condition enables the follower to go all the way around the cam, not stop- ping at the broken faces or following the extension of a single face. n CamMateTangent: Cylindrical or planar face mated to a cam that is created from multi- ple faces. This condition enables the follower to go all the way around the cam, not stop- ping at the broken faces or following the extension of a single face. Figure 13.11 shows both single-face and multi-face cams, along with the Cam Mate interface. The two assemblies are available from the CD-ROM in the file named Chapter 13 Cam.sldasm. If you open the assemblies and spin the cam plate, you will notice that in both cases, the flat fol- lower does not work very well. In fact, in the single face cam assembly, it does not work at all. Barrel (cylindrical) cams cannot use the Cam mate to create cam motion. NOTE NOTE 424 Working with Assemblies Part III 20_080139 ch13.qxp 3/26/07 3:54 PM Page 424 [...]... shown in Figure 14 .5 You can access this dialog box by right-clicking the configuration name in the ConfigurationManager 444 21_080139 ch14.qxp 3/26/07 3 :56 PM Page 4 45 Assembly Configurations and Display States FIGURE 14.4 The Advanced option for assemblies in the Open dialog box FIGURE 14 .5 The Advanced Show/Hide Components dialog box 4 45 14 21_080139 ch14.qxp Part III 3/26/07 3 :56 PM Page 446 Working... look as shown in Figure 13.22 434 20_080139 ch13.qxp 3/26/07 3 :54 PM Page 4 35 Getting More from Mates FIGURE 13.21 Displaying a SmartMate when dragging between windows Drag the inner face of the hole 9 Open a Windows Explorer window, and select the following parts: Chapter 13 Robot Arm2 and Chapter 13 Robot Gripper Drag these parts into the SolidWorks assembly window, and drop them in a blank space 10... combination of Concentric and Coincident mates Figure 13.23 shows the selections and the results 4 35 13 20_080139 ch13.qxp Part III 3/26/07 3 :54 PM Page 436 Working with Assemblies FIGURE 13.22 Creating a Width mate FIGURE 13.23 Making conical faces coincident Select these faces 436 20_080139 ch13.qxp 3/26/07 3 :54 PM Page 437 Getting More from Mates 11 Create a copy of the gripper part so that there are... show how they are used in conjunction with SolidWorks assemblies The Display States function was new in SolidWorks 2006 Display States are a better performance alternative to using configurations to control visibility of parts in assemblies Display State options are discussed at length in this chapter Using Display States If you are using an older version of SolidWorks, then you may not have access to... cannot edit the part in the assembly unless the active configuration is the same as the config used in the assembly This has always been the case What is new about SolidWorks 2007 is that if you open the part in its own window from the assembly, SolidWorks automatically makes the config that is used in the assembly the active config As a result, to change the active config and edit the part in the assembly,... within a certain range of values Figure 13. 15 shows the PropertyManager interface for the Limit Angle mate Limit mates accept zero and negative values that are not normally accepted for dimensions in SolidWorks When used properly, Limit mates can be an extremely powerful tool for creating more realistic motion in assemblies 426 20_080139 ch13.qxp 3/26/07 3 :54 PM Page 427 Getting More from Mates FIGURE... cause of the conflict Figure 13.18 shows the Mate Xpert interface You can access the Mate Xpert from the RMB menu 430 20_080139 ch13.qxp 3/26/07 3 :54 PM Page 431 Getting More from Mates FIGURE 13.18 The Mate Xpert interface In the past several releases, SolidWorks has become increasingly “error-phobic.” There are more and more ways to create mate errors that are simply not reported to the user For... the Mate reference 433 13 20_080139 ch13.qxp Part III 3/26/07 3 :54 PM Page 434 Working with Assemblies FIGURE 13.20 A Mate reference being used to SmartMate a component 4 Open the part with the filename Chapter 13 Arm.sldprt in its own window, and click Window ➪ Tile Vertically The part and the assembly should be open in adjacent windows 5 Click the face inside the hole without the chamfer around it... only requires two faces and a plane Figure 13.12 shows a good application for a Width mate as well as the PropertyManager interface for the mate FIGURE 13.12 Applying a Width mate 4 25 13 20_080139 ch13.qxp Part III 3/26/07 3 :54 PM Page 426 Working with Assemblies Gear mate The Gear mate enables you to establish gear type relations between parts without making the parts physically mesh You can also apply...20_080139 ch13.qxp 3/26/07 3 :54 PM Page 4 25 Getting More from Mates FIGURE 13.11 Using Cam mates Width mate The Width mate is often used as a replacement for the Symmetric mate in situations where parts are modeled with some tolerance, . PropertyManager is active, SolidWorks does not add the selected entity to the Mate Selections list. CAUTION CAUTION 4 15 Getting More from Mates 13 20_080139 ch13.qxp 3/26/07 3 :54 PM Page 4 15 To summarize. Mates 13 20_080139 ch13.qxp 3/26/07 3 :54 PM Page 421 A good example of this kind of problem with motion can be found in one of the sample assemblies that installed with SolidWorks 2007. I have included this. interface for the mate. FIGURE 13.12 Applying a Width mate 4 25 Getting More from Mates 13 20_080139 ch13.qxp 3/26/07 3 :54 PM Page 4 25 Gear mate The Gear mate enables you to establish gear type