SolidWorks Motion Tutorials

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(1)PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e ® SolidWorks. 2011. SolidWorks Motion. Dassault Systèmes SolidWorks Corporation 300 Baker Avenue Concord, Massachusetts 01742 USA.

(2) COMMERCIAL COMPUTER SOFTWARE PROPRIETARY U.S. Government Restricted Rights. Use, duplication, or disclosure by the government is subject to restrictions as set forth in FAR 52.227-19 (Commercial Computer Software Restricted Rights), DFARS 227.7202 (Commercial Computer Software and Commercial Computer Software Documentation), and in the license agreement, as applicable. Contractor/Manufacturer: Dassault Systèmes SolidWorks Corporation, 300 Baker Avenue, Concord, Massachusetts 01742 USA. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. © 1995-2010, Dassault Systèmes SolidWorks Corporation, a Dassault Systèmes S.A. company, 300 Baker Avenue, Concord, Mass. 01742 USA. All Rights Reserved. The information and the software discussed in this document are subject to change without notice and are not commitments by Dassault Systèmes SolidWorks Corporation (DS SolidWorks). No material may be reproduced or transmitted in any form or by any means, electronically or manually, for any purpose without the express written permission of DS SolidWorks. The software discussed in this document is furnished under a license and may be used or copied only in accordance with the terms of the license. All warranties given by DS SolidWorks as to the software and documentation are set forth in the license agreement, and nothing stated in, or implied by, this document or its contents shall be considered or deemed a modification or amendment of any terms, including warranties, in the license agreement. Patent Notices SolidWorks® 3D mechanical CAD software is protected by U.S. Patents 5,815,154; 6,219,049; 6,219,055; 6,611,725; 6,844,877; 6,898,560; 6,906,712; 7,079,990; 7,477,262; 7,558,705; 7,571,079; 7,590,497; 7,643,027; 7,672,822; 7,688,318; 7,694,238; and foreign patents, (e.g., EP 1,116,190 and JP 3,517,643). eDrawings® software is protected by U.S. Patent 7,184,044; U.S. Patent 7,502,027; and Canadian Patent 2,318,706. U.S. and foreign patents pending.. Trademarks and Product Names for SolidWorks Products and Services SolidWorks, 3D PartStream.NET, 3D ContentCentral, eDrawings, and the eDrawings logo are registered trademarks and FeatureManager is a jointly owned registered trademark of DS SolidWorks. CircuitWorks, Feature Palette, FloXpress, PhotoWorks, TolAnalyst, and XchangeWorks are trademarks of DS SolidWorks. FeatureWorks is a registered trademark of Geometric Ltd. SolidWorks 2011, SolidWorks Enterprise PDM, SolidWorks Simulation, SolidWorks Flow Simulation, and eDrawings Professional are product names of DS SolidWorks. Other brand or product names are trademarks or registered trademarks of their respective holders.. Copyright Notices for SolidWorks Standard, Premium, Professional, and Education Products Portions of this software © 1986-2010 Siemens Product Lifecycle Management Software Inc. All rights reserved. Portions of this software © 1986-2010 Siemens Industry Software Limited. All rights reserved. Portions of this software © 1998-2010 Geometric Ltd. Portions of this software © 1996-2010 Microsoft Corporation. All rights reserved. Portions of this software incorporate PhysX™ by NVIDIA 2006-2010. Portions of this software © 2001 - 2010 Luxology, Inc. All rights reserved, Patents Pending. Portions of this software © 2007 - 2010 DriveWorks Ltd. Copyright 1984-2010 Adobe Systems Inc. and its licensors. All rights reserved. Protected by U.S. Patents 5,929,866; 5,943,063; 6,289,364; 6,563,502; 6,639,593; 6,754,382; Patents Pending. Adobe, the Adobe logo, Acrobat, the Adobe PDF logo, Distiller and Reader are registered trademarks or trademarks of Adobe Systems Inc. in the U.S. and other countries. For more copyright information, in SolidWorks see Help > About SolidWorks. Copyright Notices for SolidWorks Simulation Products Portions of this software © 2008 Solversoft Corporation. PCGLSS © 1992-2007 Computational Applications and System Integration, Inc. All rights reserved.. Copyright Notices for Enterprise PDM Product Outside In® Viewer Technology, © Copyright 1992-2010, Oracle © Copyright 1995-2010, Oracle. All rights reserved. Portions of this software © 1996-2010 Microsoft Corporation. All rights reserved.. Copyright Notices for eDrawings Products Portions of this software © 2000-2010 Tech Soft 3D. Portions of this software © 1995-1998 Jean-Loup Gailly and Mark Adler. Portions of this software © 1998-2001 3Dconnexion. Portions of this software © 1998-2010 Open Design Alliance. All rights reserved. Portions of this software © 1995-2009 Spatial Corporation. This software is based in part on the work of the Independent JPEG Group.. Document Number: PMT1142-ENG_DRAFT.

(3) PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e Contents. Introduction:. About This Course . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Prerequisites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Course Design Philosophy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Using this Book . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Laboratory Exercises . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Training Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Windows® 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Conventions Used in this Book . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Use of Color . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 What is SolidWorks Motion? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 What is Motion Simulation? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Understanding Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Mass and Inertia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Degrees-of- Freedom . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Constraining Degrees-of- Freedom . . . . . . . . . . . . . . . . . . . . . . . . 6 Motion analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 How is motion analyzed on the computer?. . . . . . . . . . . . . . . . . . . 6 Basics of Mechanism Setup in SolidWorks Motion . . . . . . . . . . . . . . . 7 Rigid Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Fixed Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Floating Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Mates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Motors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Constraint Mapping Concept . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 i.

(4) Contents. SolidWorks 2011. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Lesson 1: Introduction to Motion Simulation and Forces. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Basic Motion Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Case Study: Car Jack Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Driving Motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Understanding Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Applied Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Force Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Force Direction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Case 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Case 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Case 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Results. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Plot Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Sub-Categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Resizing Plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Exercise 1: 3D Fourbar Linkage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29. Lesson 2: Building a Motion Model and Post-processing Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Creating Local Mates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Case Study: Crank Slider Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Mates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Concentric Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Hinge Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Point-to-Point Coincident Mate . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Lock Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Two Face-to-Face Coincident Mates . . . . . . . . . . . . . . . . . . . . . . 37 Universal Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Screw Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Point-on-Axis Coincident Mate . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Parallel Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39. ii.

(5) SolidWorks 2011. Contents. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Perpendicular Mate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Local Mates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 Function Builder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Importing Data Points. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 Alternative Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 Plotting Kinematic Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Absolute vs. Relative values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Output coordinate system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Angular Displacement Plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Angular Velocity and Acceleration Plots . . . . . . . . . . . . . . . . . . . 62 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Exercise 2: Piston . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Exercise 3: Trace Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71. Lesson 3: Introduction to Contacts, Springs and Dampers Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Contact and Friction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Case Study: Catapult. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 Interference Detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81 Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 Contact groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 Contact Friction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 Translational Spring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 Magnitude of Spring Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 Translational Damper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 Post-processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 Analysis with Friction (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 Exercise 4: The Bug. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93 Exercise 5: Door Closer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 Lesson 4: Advanced Contact Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99 Contact Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Case Study: Latching Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Fixing Motion with Motors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 Motor Input and Force Input Types . . . . . . . . . . . . . . . . . . . . . . 103 Functional Expressions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103. iii.

(6) Contents. SolidWorks 2011. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Force Functions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 STEP Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Contact: Solid Bodies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 Poisson Model (Restitution Coefficient) . . . . . . . . . . . . . . . . . . 110 Impact Force Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110 Closing Remarks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112 Geometrical Description of Contacts . . . . . . . . . . . . . . . . . . . . . . . . 115 Instability Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 Modifying Result Plots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119 Closing Force . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Precise Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 Integrators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123 GSTIFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 WSTIFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 SI2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 Discussion: References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127 Exercise 6: Hatchback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 Exercise 7: Conveyor Belt (No Friction). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 Path Mate Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Exercise 8: Conveyor Belt (With Friction) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146. Lesson 5: Curve to Curve Contact Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 Contact Forces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 Case Study: Geneva Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 Curve to Curve Contact . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 Solid bodies vs. curve to curve contact. . . . . . . . . . . . . . . . . . . . . . . 159 Solid Bodies Contact Solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160 Exercise 9: Conveyor Belt (Curve to curve contact with friction) . . . . . . . . . . . 161 Lesson 6: CAM Synthesis Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 CAMs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Case Study: CAM Synthesis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Generating a CAM Profile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Trace Path . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169 Exporting Trace Path Curves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170. iv.

(7) SolidWorks 2011. Contents. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Cycle based motion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173 Exercise 10: Desmodromic CAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179 Exercise 11: Rocker CAM Profile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185. Lesson 7: Flexible Joints. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 Flexible Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 Case Study: System with Rigid Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 195 Calculation of Wheel Input Motion . . . . . . . . . . . . . . . . . . . . . . 198 Understanding Toe Angles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201 System with Flexible Joints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208. Lesson 8: Redundancies. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 Redundancies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 What are redundancies? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 Effects of Redundancies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214 How are redundancies removed in the solver? . . . . . . . . . . . . . . 215 Case Study: Door Hinges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 Degrees of Freedom Calculation . . . . . . . . . . . . . . . . . . . . . . . . 219 Total Actual and Estimated DOF . . . . . . . . . . . . . . . . . . . . . . . . 219 Using Flexible Joints Option to Remove Redundancies . . . . . . 222 Limitations of Flexible Mates. . . . . . . . . . . . . . . . . . . . . . . . . . . 223 Bushing Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 How to Check For Redundancies . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Typical Redundant Mechanisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 Dual Actuators Driving a Part . . . . . . . . . . . . . . . . . . . . . . . . . . 226 Parallel Linkages. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 Exercise 12: Dynamic Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 Exercise 13: Dynamic Systems 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 Exercise 14: Kinematic Mechanism . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233 Exercise 15: Zero Redundancy Model-Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238. v.

(8) Contents. SolidWorks 2011. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Exercise 16: Zero Redundancy Model-Part 2 (Optional) . . . . . . . . . . . . . . . . . . . 243 Exercise 17: Removing Redundancies with Bushings . . . . . . . . . . . . . . . . . . . . . 244 Exercise 18: Catapult. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251. Lesson 9: Export to FEA. Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 Exporting Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Case Study: Drive Shaft . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Project Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259 FEA Export . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262 Load Bearing Faces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Mate location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263 Export of Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 SolidWorks Simulation Users Only . . . . . . . . . . . . . . . . . . . . . . 266 Direct Solution in SolidWorks Motion . . . . . . . . . . . . . . . . . . . . . . . 274 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278 Exercise 19: Export to FEA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279. Lesson 10: Event Based Simulation Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289 Event Based Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 Case Study: Sorting Device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 Servo motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290 Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291 Task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 298 Lesson 11: Design Project (Optional) Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299 Design Project. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 Case Study: Surgical Shear - Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . 300 Problem Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 Force to Cut the Catheter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301 Self Guided Problem - Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303 Self Guided Problem - Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304 Problem Solution - Part 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305 Creating the Force Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308 Force to Cut the Catheter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308. vi.

(9) SolidWorks 2011. Contents. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Creating the Force Expression . . . . . . . . . . . . . . . . . . . . . . . . . . 311 Force Expression. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313 IF Statement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313 Developing the Expression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 313 Case Study: Surgical Shear - Part 2 . . . . . . . . . . . . . . . . . . . . . . . . . 320 Stages in the Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 320 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330. Appendix A: Motion Study Convergence Solutions and Advanced Options Convergence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 334 Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335 Integrator Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336 GSTIFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336 WSTIFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337 Stabilized Index Two (SI2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337 Integrator Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337 Maximum Iterations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337 Initial Integrator Step Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337 Minimum Integrator Step Size . . . . . . . . . . . . . . . . . . . . . . . . . . 337 Maximum Integrator Step Size . . . . . . . . . . . . . . . . . . . . . . . . . . 338 Jacobian Re-evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 338 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339 Appendix B: Mate Friction Mate Friction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 342 Concentric (Spherical) Mate Friction Model . . . . . . . . . . . . . . . 343 Coincident Translational Mate Friction Model . . . . . . . . . . . . . 344 Concentric Mate Friction Model. . . . . . . . . . . . . . . . . . . . . . . . . 344 Coincident Mate (Planar) Friction Model. . . . . . . . . . . . . . . . . . 344 Universal Joint Friction Model . . . . . . . . . . . . . . . . . . . . . . . . . . 345 Friction Results Reported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 345. vii.

(10) PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e Contents. viii. SolidWorks 2011.

(11) PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e Introduction. 1.

(12) Introduction. The goal of this course is to teach you the basics of how to use the SolidWorks Motion simulation software to help you analyze the kinematic or dynamic behavior of your SolidWorks assembly model.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. About This Course. SolidWorks 2011. The focus of this course is on the fundamental skills and concepts central to the successful use of SolidWorks Motion 2011. You should view the training course manual as a supplement to, and not a replacement for, the system documentation and on-line help. Once you have developed a good foundation in basic skills, you can refer to the on-line help for information on less frequently used command options.. Prerequisites. Students attending this course are expected to have the following:. I I I. Mechanical design experience. Experience with the Windows™ operating system. Completed the on-line SolidWorks tutorials that are available under Help. You can access the on-line tutorials by clicking Help, Online Tutorial.. Course Design Philosophy. This course is designed around a process- or task-based approach to training. Rather than focusing on individual features and functions, a process-based training course emphasizes processes and procedures you should follow to complete a particular task. By utilizing case studies to illustrate these processes, you learn the necessary commands, options and menus in the context of completing a design task.. Recommended Length. The recommended minimum length of this course is two days.. Using this Book. This training manual is intended to be used in a classroom environment under the guidance of an experienced SolidWorks Motion instructor. It is not intended to be a self-paced tutorial. The examples and case studies are designed to be demonstrated “live” by the instructor.. Please note, there may be slight differences in results for certain lessons due to service pack upgrades, etc.. 2.

(13) SolidWorks 2011. Laboratory exercises give you the opportunity to apply, practice and expand the material covered during the lecture/demonstration portion of the course. They are designed to represent typical design, and analysis situations while being modest enough to be completed during class time. You should note that many students work at different paces. Therefore, we have included more lab exercises than you can reasonably expect to complete during the course. This ensures that even the fastest student will not run out of exercise.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Laboratory Exercises. Introduction. Training Files. A complete set of the various files used throughout this course can be downloaded from the SolidWorks website, www.solidworks.com. Click on the link for Support, then Training, then Training Files, then SolidWorks Simulation Training Files. Select the link for the desired file set. There may be more than one version of each file set available. Direct URL:. www.solidworks.com/trainingfilessimulation. The files are supplied in signed, self-extracting executable packages.. The files are organized by lesson number. The Case Studies folder within each lesson contains the files your instructor uses while presenting the lessons. The Exercises folder contains any files that are required for doing the laboratory exercises.. Feature Names. Throughout this course, feature names may be different from those you obtain when doing the case studies and exercises. SolidWorks and SolidWorks Motion name features sequentially, (Hinge1, Hinge2, etc.) so if you apply mates in a different order, or you delete and then recreate a mate, your names will be different. In most cases, mates are referred to by their type (lock, hinge, coincident, etc.) and the components that are mated (link, support, etc.). In addition, images are also included to help avoid ambiguity, but you must always check the instructions carefully to make sure you are selecting the correct feature.. 3.

(14) Introduction. The screen shots in this manual were made using SolidWorks 2010 and SolidWorks Motion 2010 running on Windows® 7. If you are running on a different version of Windows, you may notice differences in the appearance of the menus and windows. These differences do not affect the performance of the software.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Windows® 7. SolidWorks 2011. Conventions Used in this Book. This manual uses the following typographic conventions: Convention. Bold Sans Serif. SolidWorks Motion commands and options appear in this style. For example, Motion, Delete Results means choose the Delete Results option from the Motion menu.. Typewriter. Feature names and file names appear in this style. For example, Concentric.. 17 Do this step. Use of Color. 4. Meaning. Double lines precede and follow sections of the procedures. This provides separation between the steps of the procedure and large blocks of explanatory text. The steps themselves are numbered in sans serif bold.. The SolidWorks and SolidWorks Motion user interface make extensive use of color to highlight selected geometry and to provide you with visual feedback. This greatly increases the intuitiveness and ease of use of the SolidWorks Motion software. To take maximum advantage of this, the training manuals are printed in full color..

(15) SolidWorks 2011. Introduction. SolidWorks Motion is a virtual prototyping tool for engineers and designers interested in understanding the performance of their assemblies. Powered by ADAMS® technology, the industry leader for over 25 years, SolidWorks Motion helps you ensure that your designs will work and perform as expected prior to building them. By learning how to effectively utilize the features of the user interface, you will have the key to unlocking a solution to the most complex mechanisms.. What is Motion Simulation?. A mechanism is a mechanical device that has the purpose of transferring motion and/or force from a source to an output. Motion simulation is simply the study of such moving systems or mechanisms. The motion of any system is determined by the following:. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. What is SolidWorks Motion?. I I I I I. Mates connecting the parts The mass and inertia properties of the components Applied forces to the system Driving motions (Motors or Actuators) Time. Understanding Basics Mass and Inertia. The principle of inertia is one of the fundamental laws of classical physics which are used to describe the motion of matter and how it is affected by applied forces. Today, the concept of inertia is most commonly defined using Isaac Newton's First Law of Motion, which states: Every body perseveres in its state of being at rest or of moving uniformly straight ahead, except insofar as it is compelled to change its state by forces impressed.. Mass and inertia play a very important role in the simulation of dynamic systems and are also important in kinematics. Realistic values of mass and inertia are needed in nearly all simulations.. Degrees-ofFreedom. An unconstrained rigid body in space has six degrees-of-freedom: three translational and three rotational. It can translate along its X, Y, and Z axes and rotate about its X, Y, and Z axes as shown in the figure to the right.. 5.

(16) Introduction. SolidWorks 2011. Constraints are the restrictions placed on a part’s movement in specific degrees-offreedom. Mates are connections that restrict the movement of one part with respect to another.. Motion analysis. The two equations governing three dimensional motion of a rigid body are known as Euler’s equations.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Constraining Degrees-ofFreedom. The first equation is Newton’s second law of motion which states that the sum of externally applied forces on a body is equal to the rate of dP change of linear momentum P, ΣF = -------- . dt. For bodies where mass does not change, the right hand side of the equation simplifies to more commonly known mass times acceleration, ΣF = ma . The second equation is based on the sum of the moments about the center of mass of a rigid body due to external forces, and couples should equal the rate of change of angular momentum H of the body. dH ΣM = -------dt. How is motion analyzed on the computer?. Τhe program uses the modified Newton Raphson iteration method in each time step.. By taking very small time steps, the software can predict the position of parts at the next time step based on initial conditions or the previous time step. The solution must satisfy: I I I. 6. Velocity of parts Mates connecting parts Forces and accelerations.

(17) SolidWorks 2011. Introduction. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. The answer is iterated until certain accuracy is reached for that time step for force and acceleration values.. Basics of Mechanism Setup in SolidWorks Motion. The following paragraphs outline how SolidWorks Motion treats parts and sub-assemblies, and how the mates directly define the motion of the mechanism when loaded by external forces (such as gravity or isolated forces) or prescribed motions (motors).. Rigid Body. In SolidWorks Motion, all parts are treated as infinitely rigid. This means that there is no internal deflection within a part and the parts do not deform or change shape during the simulation. A rigid body can be a single SolidWorks part or a sub-assembly. There are two states of the sub-assembly in SolidWorks: Rigid or Flexible. A rigid sub-assembly means that the individual components that make up the sub-assembly are assumed to be rigidly attached (welded) to each other as if they were one single part.. If a sub-assembly status is set to flexible in SolidWorks, it does not mean that the sub-assembly parts become flexible. This setting means that the root level parts of the sub-assembly are treated independently of each other by SolidWorks Motion. The constraints (SolidWorks mates at the sub-assembly level) between these parts are automatically mapped into SolidWorks Motion.. Fixed Parts. A rigid body can be treated as a fixed part or a floating (moving) part. Fixed parts are, by definition, at absolute rest. Each fixed rigid body has zero degrees-of-freedom. A fixed part serves as the reference frame for the remaining rigid bodies that are moving.. In SolidWorks, any component that is fixed in your assembly is automatically treated as a fixed part when you begin a new mechanism and map the assembly constraints.. 7.

(18) Introduction. Components that move in the mechanism are considered moving parts. Each moving part has six degrees-of-freedom.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Floating Parts. SolidWorks 2011. In SolidWorks, any component that is floating in your assembly is automatically treated as moving when you begin a new mechanism and map the assembly constraints.. Mates. SolidWorks mates fully define how rigid bodies are attached and how they move relative to each other. Mates remove degrees-of-freedom from the parts to which they are attached.. When you add a mate, such as a concentric mate, between two rigid bodies, you remove degrees-of-freedom, causing them to remain positioned with respect to each other regardless of any motion or force in the mechanism.. Motors. Motors can be defined for part to control its movement over a period of time. A motor dictates the displacement, velocity, or acceleration of a part as a function of time.. Gravity. Gravity is an important quantity when the weight of a part has an influence on its simulated motion, such as a body in free fall. In SolidWorks Motion, gravity consists of two components:. I I. Direction of the gravitational vector Magnitude of gravitational acceleration. The Gravity Properties dialog allows you to specify the direction and magnitude of the gravitational vector. You can specify the gravitational vector by entering the x, y and z values in the appropriate text box, or by specifying a reference plane. The magnitude must be entered separately. The default value for the gravitational vector is (0, -1, 0), and the magnitude is 9.81 m/s2 (or the equivalent in the currently active units).. Constraint Mapping Concept. One of the reasons SolidWorks Motion is such a time saving tool is that it automatically maps the SolidWorks assembly mates (constraints) to SolidWorks Motion. There are more than 100 ways to mate or constrain parts in SolidWorks.. Forces. When defining various Force objects in SolidWorks Motion, a location and/or direction has to be specified. These directions and locations are derived from selected SolidWorks entities. The entities can be sketch points, vertices, edges or surfaces.. Summary. This short review of motion simulation using SolidWorks Motion is not, of course, all inclusive. It is only intended to get us started with the hands-on lessons. As we progress through the lessons presented in the following chapters, we will occasionally digress from software-specific issues in order to discuss relevant motion simulation fundamentals.. 8.

(19) PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e Lesson 1 Introduction to Motion Simulation and Forces. Objectives. Upon successful completion of this lesson, you will be able to: I. Use Assembly Motion to animate the motion of a car jack assembly.. I. Use SolidWorks Motion to simulate physical behavior of the car jack and determine the torque required to lift a vehicle.. 9.

(20) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. In this lesson, we will perform a basic motion analysis using SolidWorks Motion to simulate the weight of a vehicle on the jack and determine the torque required to lift it. Engineers can then use this information to choose the required electric motor to drive the car jack.. Case Study: Car Jack Analysis. A mechanical jack is a device that lifts heavy equipment. The most common form is a car jack, floor jack, or garage jack which lifts vehicles so that maintenance can be performed. Car jacks usually use mechanical advantage to allow a human to lift a vehicle. More powerful jacks use hydraulic power to provide more lift over greater distances. Mechanical jacks are usually rated for a maximum lifting capacity (e.g., 1.5 tons or 3 tons).. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Basic Motion Analysis. Because this is our first motion analysis, no contact is used and the tilting motion of the jack is prevented with the help of the mates.. Problem Description. The car jack will be driven at a rate of 100 RPM and will be loaded with a force of 8,900 N., representing the weight of a vehicle. Determine the torque and power required to lift the load through the range of motion of the jack.. Stages in the Process. I. Create a Motion Study.. This will be a new motion study.. I. Add a rotary motor.. The rotary motor will drive the jack.. I. Add gravity.. Normal gravity will be added so that the weight of the car jack components are considered in the calculations.. I. Add the weight of the car.. The weight of the car will be added as a downward force on the Support.. I. 10. Calculate the motion..

(21) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. The default analysis will run for five seconds but we will increase it to allow the jack to extend fully. I. Plot the results.. We will create various plots to show the torque and power required.. 1. Ensure that SolidWorks Motion is added in. Under Tools, Add-ins, make sure SolidWorks Motion is checked.. 2. Open an assembly file. Open Car_Jack from the Lesson01\Case Studies folder.. 11.

(22) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. 3. Set the document units.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. SolidWorks Motion uses the document units set in the SolidWorks document. Click Tools, Options, Document Properties, Units.. Select MMGS (millimeter, gram, second) for the Unit system. This will set our length units to millimeters and force to Newtons.. 12.

(23) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. Change to the Motion Study. Click on the Motion Study 1 tab that appears at the bottom left-hand corner of the window. If this tab is not visible, select Motion Manager on the View menu.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 4. 13.

(24) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. Motion can be driven by gravity, springs, forces or motors. Each has different characteristics that can be controlled.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Driving Motion Introducing: Motors. Motors can create either linear, rotary or path dependent motion or to prevent motion. This motion can be defined in a number of different ways. I. Constant Speed. The motor will drive at a constant velocity.. I. Distance. The motor will move for a fixed distance or degrees.. I. Oscillating. Oscillating motion is a back and forth motion at a specific distance at a specified frequency.. I. Segments. Motion profile is constructed from segments of the most commonly used functions such as linear, polynomial, half-sine and others.. I. Data Points. Interpolated motion is driven by a tabular set of values.. I. Expression. The motor can be driven by a function created from existing variables and constants.. I. Servo Motor. The motor used to implement control actions for the event-based triggered motion.. Where to Find It. 14. I. On the MotionManager toolbar, click Motor. ..

(25) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. Create a Motor that drives the Screw_rod at 100 RPM. Click Motor on the Motion Manager toolbar.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 5. Under Motor Type, select Rotary Motor.. Under Component Direction, select the cylindrical face of the Screw_rod part as shown in the figure. The Motion Direction field will automatically populate the same face to specify the direction.. Use the Reverse Direction button to orient the motor (see the figure). Leave the Component to move relative to field empty. This ensures that the motor direction is specified with respect to the global coordinate system. Under Motion, select the Constant speed and enter a value of 100 RPM. Click OK.. Important!. Make sure that the motor is oriented as shown in the figure.. 15.

(26) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Click the graph in the PropertyManager to view the enlarged plot.. Close the graph plot and click OK to close the Motor PropertyManager.. 6. Type of Study.. Make sure that the Motion Type of Study field shows Motion Analysis.. Gravity. Gravity is an important quantity when the weight of a part has an influence on its simulated motion, such as a body in free fall. In SolidWorks Motion, gravity consists of two components: I I. Direction of the gravitational vector Magnitude of the gravitational acceleration. The Gravity Properties allows you to specify the direction and magnitude of the gravitational vector. You can specify the gravitational vector by selecting the X, Y and Z direction or by specifying a reference plane. The magnitude must be entered separately. The default value for the gravitational vector is Y and the magnitude is 9806.55 mm/sec2 or the equivalent in the currently active units.. 16.

(27) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. Apply Gravity to the assembly. Click Gravity on the Motion Manager toolbar.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 7. For Gravity Parameters, Direction Reference, select the Y direction.. Under Numeric gravity value, type in a value of 9806.65 mm/sec^2. Click OK.. Forces. Force entities (including both forces and moments) are used to effect the dynamic behavior of parts and sub assemblies of a motion model and are usually a representation of some external effect acting on the analyzed assembly. Forces may resist or induce motion, and are defined using similar functions that are used to define motors (constant, step, function, expression or interpolated).. Forces in SolidWorks Motion can be divided into two basic groups: I. Action Forces. A single applied force or moment representing the effect of the external objects and loadings on the part or subassembly. The weight of the vehicle applied on the car jack or an aerodynamic force on the car body are examples of action forces.. I. Action and Reaction Forces. A pair of forces or moments, both action and corresponding reaction, are applied on the parts or subassemblies.. A spring force could be understood as action and reaction force because both are acting on the same line of action and acting on the assembly at the spring mount points. Another example would be a person pushing with his/her arms on the two opposing parts of an assembly. Such a person can then be represented in the motion analysis by a pair of two opposing forces of equal magnitude on the same line of action, i.e. action and reaction forces.. Understanding Forces. A force can define load or compliance on a part. SolidWorks Motion provides the following type of forces:. 17.

(28) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. Applied forces are forces that define loads at specific locations on a part. You must provide you own description of the force behavior by specifying a constant force value or a function expression. The applied forces available in SolidWorks Motion are the applied force, applied torque, action/reaction force and action/reaction torque.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Applied Forces. The orientation of action-only forces can be fixed or at relative to the orientation of any part in the mechanism. Applied forces are used to model inputs such as actuators, rockets, aerodynamic loads and many more.. Force Definition. To define a force the following information must be specified:. I I I. Part or parts on which the forces act. Point of the force application. Magnitude and direction of the force.. On the MotionManager toolbar, click Force Only in the PropertyManager.. . Select Action-. Where to Find It. I. Force Direction. The force direction is based on the reference part you select in the Force Direction box. An illustration below gives you the three cases on how the force direction changes based on the selected reference parts.. Case 1. Direction of force is based on a fixed component.. If fixed component is the assembly origin then the initial orientation of the force will be held constant throughout the simulation. Reference Fixed Component. F1. 18. F1. F1.

(29) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. Direction of force is based on the selected moving component, which is also the component on which you want to apply the force.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Case 2. If the part to which the force is applied is used as the reference datum, then the force will remain locked in its relative orientation to the body over the entire simulation time (i.e. it will stay in alignment with the geometry on the body used to define the direction). Reference Rotating Component. F1. F1. F1. Fixed Component. Case 3. Direction of force is based on the selected moving component which is different from the component on which you want to apply the force.. If another moving part is used as the reference datum, the direction of the force will change based on the relative orientation of the reference body to the moving body. This is hard to visualize easily, but if you apply the force on a body that is held locked in position, and use a rotating part as the reference datum, you should see the force rotates in concert with the reference body. Reference Rotating Component. F1. Note. F1. F1. Make sure that the gravity symbol shows the orientation in the negative Y direction.. 19.

(30) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. Create a force of 8900 N to simulate the weight of the car on the car jack. Click Force on the Motion Manager.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 8. For Type, select Force.. Under Direction, select Action Only.. Under Action part and point of application of action, select the circular edge on component Support-1 (see image below). For Force Direction, select the vertical edge on the Base-1 component.. The default force direction is defined by the circular edge selected in the Action part and point of application of action field, i.e. perpendicular to the plane of the edge. Because the default direction is correct in this case, the edge selected in the Force Direction field is not required and is done solely for the educational purpose.. Note. Under Force Function, select Constant. Enter a force value of 8900 N.. Make sure that the force is directed downwards.. Note. Click OK to close the Force/Torque PropertyManager.. 9. 20. Run the Simulation. Click Calculate . The simulation will calculate for 5 seconds..

(31) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. 10 Run the Simulation for 8 seconds.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Drag the end time key to 8 seconds on the timeline and recalculate.. Results. The primary output from a motion study is a plot of one parameter versus another, usually time. Once the motion is calculated plots can be created for a variety of parameters. All existing plots will be listed at the bottom of the MotionManager tree.. Plot Categories. Plots of the following categories can be created: I I I I. Sub-Categories. Displacement Acceleration Momentum Power. I I I I. Displacement Forces Energy Other quantities. Within each of the categories, plots can be created for: I I I I I I I I I I I I I I. Trace Path Linear Displacement Linear Acceleration Angular Velocity Applied Force Reaction Force Friction Force Contact Force Angular Momentum Angular Kinetic Energy Potential Energy Delta Pitch Roll Bryant Angles. I I I I I I I I I I I I I I. XYZ Position Linear Velocity Angular Displacement Angular Acceleration Applied Torque Reaction Moment Friction Moment Translational Momentum Translational Kinetic Energy Total Kinetic Energy Power Consumption Yaw Rodriguez Parameters Projection Angles. Resizing Plots. Plots can be resized by dragging any border or corner.. Where to Find It. I. Click Results and Plots. on the MotionManager toolbar.. 21.

(32) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 11 Plot the torque required to lift the weight of the car. Click Results and Plots in the Motion manager.. Under Result, select the category as Forces. Under Sub-category, select Motor Torque.. Under Result component, select Magnitude.. Under Select rotational motor object to create result, select the motor that we created (see image below). Click OK.. The plot of torque required appears in the graphics area.. The required torque is about 7244 N-mm.. 22.

(33) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. Once the Rotary Motor1 is selected, a triad is displayed in the graphics area. This triad indicates the local X, Y and Z axes of the motor in which the output quantities may be displayed. In the present case we require the plot of the magnitude which is independent of the coordinate system. The post-processing is described in greater detail in the next lesson.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Note. 12 Plot the power consumed to lift a weight of 8900 N. We will add this plot into an existing graph. Click Results and Plots in. the Motion Manager toolbar.. Under Result, select the category as Momentum/Energy/Power. Under Sub-category, select Power Consumption.. Under Select motor object to create result, select the same motor that you selected in the previous step.. Under Plot Results, select Add to existing plot and select Plot1 from the pull down menu. Click OK.. The power consumption is 76 Watts. Based on the torque and the power information, we can select an electric motor and use it to drive the Screw_rod instead of a human hand. You can click Play to see the animation. The vertical time bar in both the MotionManager and the graph indicates the time.. 23.

(34) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 13 Plot the vertical position of the Support. Click on the Results and Plots icon in the Motion Manager.. Under Result, select the category as Displacement/Velocity/ Acceleration. Under Sub-category, select Linear Displacement. For Result Component, select Y-component.. For Select two points/faces, select the top face of the support. If no second item is selected, the ground serves as the default second component, or the reference. Leave the Component to define XYZ directions field empty. This indicates that the displacement is reported in the default global coordinate system.. Note. The displacement is measured at the origin of the Support part file, indicated as the small blue sphere in the above figure, with respect to the origin of the Car_Jack assembly file. The result is reported in the default global coordinate system. Click OK.. 24.

(35) SolidWorks 2011. Lesson 1. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Introduction to Motion Simulation and Forces. The above graph indicates change of the global Y coordinate of the origin of the Support part file. The displacement is therefore 51mm (212-161mm) in the positive global Y axis.. 14 Modify the graph.. Modify the ordinate of the graph to show the angular displacement of the motor.. In the MotionManager tree, expand the Results folder. Right-click Plot2 and click Edit Feature. Under Plot Results, Plot Results verus: select New Result.. For Define new result, select Displacement/ Velocity/Acceleration.. Select Angular Displacement under sub-category.. Select Magnitude for result component.. Select RotaryMotor1 for the simulation element. Click OK.. 25.

(36) Lesson 1. SolidWorks 2011. Introduction to Motion Simulation and Forces. 15 Examine the graph.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. The result plot is a little coarse and the data ordinate does not cover the full range of -180 to 180 degrees. To generate a graph with finer detail, more data must be saved to disk.. Introducing: Study Properties. SolidWorks Motion has its own set of properties to control the way the study is calculated and displayed. Study properties will be discussed throughout the book. Click Motion Study Properties. on the MotionManager toolbar.. Where to Find It. I. Introducing: Frames per Second. Frames per second controls how often the data is saved on the disk. The higher the frames per second, the more dense the data recorded.. Where to Find It. I. In the Motion Study Properties, expand Motion Analysis and either type the number, use the spinbox arrows or adjust the slider.. 16 Modify Motion Study properties. Click Motion Study Properties in the. MotionManager toolbar.. Change the Frames per second to 100.. Click OK.. 26.

(37) SolidWorks 2011. Lesson 1 Introduction to Motion Simulation and Forces. 17 Calculate the study.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Notice that we have more detail and the angular displacement is nearly from -180 to 180 degrees.. 18 Save and close the file.. 27.

(38) Lesson 1. SolidWorks 2011. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Introduction to Motion Simulation and Forces. 28.

(39) SolidWorks 2011. Exercise 1 3D Fourbar Linkage. Exercise 1: 3D Fourbar Linkage. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. This assembly is a simple mechanism called 3D Fourbar linkage. There are only four parts in the mechanism. The Support part is grounded, and the rotation of the Lever part will cause a sliding motion of the SliderBlock part.. LeverArm. linkage. Support. SliderBlock. This exercise reinforces the following skills: I I. Project Description. Basic Motion Analysis on page 10. Results on page 21.. The LeverArm will be simply rotated with a constant 360 deg/sec angular velocity. Determine the amount of torque required to drive this mechanism and plot it from the motion simulation.. 1. Open an assembly file.. Open 3D Fourbar linkage from the Lesson01\ Exercises folder.. 2. Verify fixed and moving components.. Make sure that support is fixed while the other components can move.. 3. Motion study.. In the MotionManager, select Motion Analysis.. The default Motion Study 1 will be used for the analysis.. 4. Add gravity.. Apply gravity in the negative Z direction.. 29.

(40) Exercise 1. SolidWorks 2011. 3D Fourbar Linkage. Define motion of the Lever Arm. Define a Rotary Motor at 360 deg/sec.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 5. You can enter 360 deg/sec directly into the PropertyManager and it will automatically be converted to RPM.. Tip. 6. Motion study properties.. Set the Frames per second to 100 and drag the time key to 4 seconds.. 7 8. Calculate the simulation.. Determine the torque and power required to drive the mechanism.. Define a graph showing the moment torque and the required power as a function of time. Define both quantities in a single graph.. 30.

(41) SolidWorks 2011. Exercise 1 3D Fourbar Linkage. 9. Linear velocity of the SliderBlock.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Plot a graph showing the linear velocity of the SliderBlock as a function of time.. 10 Modify the graph.. Modify the ordinate of the graph to show the angular displacement of the Rotary Motor. This way the graph will show the variation of the SliderBlock velocity relative to the angular displacement of the LeverArm.. 11 Save and close the file.. 31.

(42) Exercise 1. SolidWorks 2011. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 3D Fourbar Linkage. 32.

(43) PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e Lesson 2 Building a Motion Model and Post-processing. Objectives. Upon successful completion of this lesson, you will be able to: I. Build proper SolidWorks Motion models for kinematic simulation.. I. Create local mates for a SolidWorks Motion study.. I. Create and modify plots for post-processing.. 33.

(44) Lesson 2. SolidWorks 2011. Building a Motion Model and Post-processing. In the previous lesson, the mates created in SolidWorks were used as joints in SolidWorks Motion. If the components are not mated in SolidWorks, or if we wish to examine different connection types in SolidWorks Motion, mates can be added or modified in the Motion Analysis.. Case Study: Crank Slider Analysis. In this lesson, we will setup the mechanism for the crank slider model. We will use SolidWorks mates that most closely represent the real mechanical connections. The crank slider model is used in a variety of engineering applications, such as a steam engine or the cylinder of an internal combustion engine. Therefore, we will apply a motor on the crank part, run the simulation, and then postprocess some results to estimate the required torque.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Creating Local Mates. Crank. Arm Mount. Link2. Link1. Arm. Crank Housing. Collar Shaft Collar. Problem Description. The crank is driven at a constant angular velocity of 60 RPM. Determine the torque required to rotate the crank part.. Stages in the Process. I. Create a motion study.. I. Preprocessing.. Add local mates to the assembly with the motion study active.. I. Run the simulation.. Calculate the motion.. I. Post-processing.. Plot and analyze the results.. 1. Open an assembly file.. Open 3dcrankslider from the Lesson02\Case Studies folder.. 34.

(45) SolidWorks 2011. Lesson 2 Building a Motion Model and Post-processing. 2. Examine the assembly.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. SolidWorks Motion assumes that all components that are fixed in SolidWorks are considered to be grounded parts, and all components that are floating are assumed to be moving parts. However, the movement of these parts is constrained by the SolidWorks mates.. There are no mates in this assembly, but three parts are fixed. The collar_shaft, arm_mount and crank_housing are fixed as these are parts that would be connect to ground and will have no motion in the assembly.. Fixed. No Mates. The remaining parts will need mates to constrain their motion to that expected of the mechanical system.. Mates. Mates are used to constrain the relative motion of a pair of rigid bodies by physically connecting them.. Note. A rigid body acts and moves as a single unit. SolidWorks components situated at the root level are considered rigid bodies. This means that SolidWorks and SolidWorks Motion treat subassemblies as single rigid bodies. Mates can be classified into two main types: I. Mates used to constrain the relative motion of a pair of rigid bodies by physically connecting them. Examples: Hinge, Concentric, Coincident, Fixed, Screw, Cam, etc.. I. Mates used to enforce standard geometric constraints. Examples: Distance, Angle, Parallel, etc.. Below are some descriptions of some of the most commonly used mate types. For a comprehensive understanding of all the other mates, please refer to the SolidWorks help.. 35.

(46) Lesson 2. SolidWorks 2011. Building a Motion Model and Post-processing. The concentric mate allows both relative rotation as well as relative translation of one rigid body with respect to another rigid body. The concentric mate origin can be located anywhere along the axis about which the rigid bodies can rotate or slide with respect to each other. Example: Piston sliding and rotating inside a cylinder.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Concentric Mate. Hinge Mate. Hinge mate is essentially concentric mate with the restricted translation between the two components.. In SolidWorks Motion, the hinge mate is used rather than a combination of concentric and coincident because the mechanical joint is a hinge. Hinge mates are found in the Mechanical Mates tab of the Mate PropertyManager.. 36.

(47) SolidWorks 2011. Lesson 2 Building a Motion Model and Post-processing. This type of mate permits free rotation about a common point of one rigid body with respect to another rigid body. The origin location of this mate determines the point about which the rigid bodies can pivot freely with respect to each other. Example: Ball and Socket joint.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Point-to-Point Coincident Mate. Lock Mate. The lock mate locks two rigid bodies together so they may not move with respect to each other. For a lock mate, the origin location and orientation does not affect the outcome of the simulation. A real world example of a lock mate is a weld that holds two parts together.. Two Face-to-Face Coincident Mates. This mate allows one rigid body to translate along a vector with respect to a second rigid body. The rigid bodies may only translate, not rotate, with respect to each other.. The location of the origin of a translational joint with respect to its rigid bodies does not affect the motion of the two bodies but does affect the reaction or the bearing loads.. 37.

(48) Lesson 2. SolidWorks 2011. Building a Motion Model and Post-processing. A universal mate permits the transfer of rotation from one rigid body to another rigid body. This mate is particularly useful to transfer rotational motion around corners, or to transfer rotational motion between two connected shafts that are permitted to bend at the connection point (such as the drive shaft on an automobile).. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Universal Mate. The origin location of the universal mate represents the connection point of the two rigid bodies. The two shaft axes identify the center lines of the two rigid bodies connected by the universal joint. Note that SolidWorks Motion uses rotational axes parallel to the rotational axes you identify but passing through the origin of the universal mate.. Screw Mate. The screw mate constrains one rigid body to rotate as it translates with respect to another rigid body.. When defining a screw mate, you can define the pitch. The pitch is the amount of relative translational displacement between the rigid bodies for each full rotation of the first rigid body. The displacement of the first rigid body relative to the second rigid body is a function of the rotation of the first rigid body about the axis of rotation. For every full rotation, the displacement of the first rigid body along the translation axis with respect to the second rigid body is equal to the value of the pitch.. 38.

(49) SolidWorks 2011. Lesson 2 Building a Motion Model and Post-processing. This type of mate permits one translational and three rotational motions of one part with respect to another. The translational motion between the parts is confined to the orientation axis. The point defines the initial pivot location on the axis.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Point-on-Axis Coincident Mate. Parallel Mate. A parallel mate permits only translational motion of one part with respect to another. No rotation is allowed.. In the picture below, the blue x part can move relative to the ground in the X direction. The red y part can move relative to the x part in the Y direction. The z part can move relative to the y part in the Z direction. Finally, the red/yellow/blue cube on the z part has a curvilinear motion relative to the ground but always stays parallel.. 39.

(50) Lesson 2. SolidWorks 2011. Building a Motion Model and Post-processing. Perpendicular Mate. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. The perpendicular mate allows both translational and rotational motion of one part with respect to another. It imposes a single rotational constraint on the components so that the component axes remain perpendicular. This allows relative rotations about either z-axis, but does not allow any relative rotation in the direction perpendicular to both z-axes.. It is recommended that the mates are representing the real mechanical connections as closely as possible, i.e. mechanical hinge should be modeled using the hinge mate and not using a combination of coincident and concentric mates.. Local Mates. Mates created in SolidWorks can be transferred to the Motion Analysis and used as mechanical joints. If there are no mates in the SolidWorks assembly or if we wish to define the connections differently than the SolidWorks mates, we can add local mates directly to the motion study. Local mates only apply to the study to which they were added. To add local mates, make a motion study active and add the mates. With a motion study active, any mate added is only applied in that motion study.. 3. Verify the document units.. Verify that the document units are set to MMGS (millimeter, gram, second).. 4. Create a Motion Study.. Right-click the Motion Study 1 tab and click Create New Motion Study.. Make sure that the Motion Analysis is selected as the Type of Study in the MotionManager.. 40.

(51) SolidWorks 2011. Lesson 2 Building a Motion Model and Post-processing. 5. Move components.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Move the components that are not fixed to separate the assembly. We are doing this only to make it easier to select faces and to keep track of what components are mated.. 6. Create a local mate.. Add a mate and select Hinge from the Mechanical Mates section. For Concentric Selections, select the two cylindrical faces of the shaft and hole shown with red arrows. For Coincident Selections, select the end face of the shaft and crank housing shown with the blue arrows.. Click OK.. 41.

(52) Lesson 2. SolidWorks 2011. Building a Motion Model and Post-processing. 7. Warning.. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Because the timeline is active, the mate changes the position of the crank at the starting position of the animation. This is OK for what we are doing.. Click Yes.. 8. Examine the mate.. Notice that this mate is only located in the MotionManager and not in the FeatureManager design tree.. 42.

(53) SolidWorks 2011. Lesson 2 Building a Motion Model and Post-processing. Add additional mates. Add a concentric mate between the two. Link1. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. 9. spherical surfaces shown on the parts Link1 and crank.. crank. Concentric. 10 Mate arm to arm_mount. Add a hinge mate to connect the arm to the arm_mount.. 11 Mate Link1 to the arm.. This connection requires two hinge mates, one between Link1 and cardian, and a second hinge mate between cardian and arm.. 43.

(54) Lesson 2. SolidWorks 2011. Building a Motion Model and Post-processing. 12 Mate Link2. Link2 will use a hinge mate to connect the arm. As there is no pin. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Hinge. going through the two holes, the coincident selections will be the two touching faces.. Mate the other end of Link2 to the pin on the collar with just a concentric mate.. Concentric. 13 Mate collar to collar_shaft.. Add a concentric mate between a cylindrical surface on each part.. 14 Test the assembly.. Rotate the crank and make sure the components move as expected.. Check the FeatureManager design tree and the Motion Study tree. All the mates should just be in the Motion Study tree.. 15 Add gravity.. Add gravity in the negative Y direction.. 16 Calculate.. Adjust the assembly key to 5 seconds. Click Calculate Simulation. .. 17 Play the simulation.. Play the simulation at 25% speed.. The crank will rock back and forth as gravity affects the components and potential and kinetic energy are exchanged. As there is no friction, the parts will continue to move without end.. 18 Set the timebar to 0s.. To add a motor at time 0s, the timebar needs to be set to 0s.. 19 Add a motor.. Create a Motor that drives the crank. Click Motor. on the Motion Manager.. Under Motor Type, select Rotary Motor.. Under Motor Location, select the cylindrical face of the crank part (as shown in the figure). The default selection for the Motor Direction is correct for this analysis. Make sure that the motor is oriented as shown in the figure.. 44.

(55) SolidWorks 2011. Lesson 2 Building a Motion Model and Post-processing. PR Do E no RE t c LE op AS y E or D di RA st F rib T ut e. Under Motion, select the Motor Type as Data Points. The command invokes the Function Builder window. Make sure that Value (y) and Independent variable (x) are set to Displacements (deg) and Time (s).. Function Builder. Function Builder can be used to construct functional expression for motors and forces.. Introducing: Function Builder. Function Builder can build functional expressions using predefined Segments, imported set of discrete Data Points or mathematical Expressions. The figure below shows the segment view of the Function Builder window.. I. Segments. In Segment view, user select both the independent (typically time) and dependent variable (displacements, velocity or acceleration). For each specified interval, the transition from the initial to final value is controlled using one of the predefined profiles curves. The following profile curves have been implemented: Linear, Cubic,. 45.

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