SolidWorks运动仿真培训

– 机械关节是约束零件相互运动的连接
Joint motion运动副 Gravity重力
© 2007 SolidWorks Corp. Confidential.
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Constraint Mapping约束映射
Mapping of SolidWorks assembly mates (constraints) to COSMOSMotion joints.
仿真求解必须满足以下要求：
零件的速度 零件间的配合关系 力和加速度 结果会一直迭代计算直到达到该时间步上的力和加速度值的 某一精度为止。
© 2007 SolidWorks Corp. Confidential.
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运动副基础知识（1）
Revolute铰接副 Cylindrical圆柱副
方向
构件1
– Greater than zero degrees of freedom
自由度数大于零
© 2007 SolidWorks Corp. Confidential.
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Understanding Basics运动基础
Mass and Inertia质量和惯性
– Newton’s First Law牛顿第一定律 – Conservation of momentum动力守恒
作用在零件运动上的特定自由度的限制
– Mechanical joints are connections that restrict the movement of one part to another
y
x
Pendulum restrained to pivot about mounting point
构件2
原点
约束2个旋转，3个移动自由度
约束2个旋转，2个移动自由度
© 2007 SolidWorks Corp. Confidential.
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运动副基础知识（2）
Translational 移动副
方向
Spherical球形副
y-axis
x-axis
原点
z-axis
原点
约束3个旋转，2个移动自由度
© 2007 SolidWorks Corp. Confidential.
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Mechanism types机构类型
Kinematic System运动学系统
– Movement of part(s) under enforced or constrained motion
外加或强制运动下的部件动作
所有的装配约束被映射为连接，包括曲面和曲面的约束 (如： 圆柱面/平面相切、圆柱面/圆柱面相切) 。这些是共有的连接 。
© 2007 SolidWorks Corp. Confidential.
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映射的约束
SW Geometry Point Point Point Point Point Point Point Point Line Line Line Line Line SW Geometry Point Point Line Line Plane Plane Cylinder Cylinder Line Line Line Line Line 装配关系 重合 距离 重合 距离 重合 距离 重合 同轴 重合 距离 角度 平行 垂直 运动约束 PointPoint PointPointDist PointLine PointLineDist PointPlaneDist PointPlaneDist PointLineDist PointLine LineLine LineLineDist LineLineAng LineLineAng (0 deg.) LineLineAng (90 deg.)
基础约束类型合并为简化的机械约束
– One Orthogonal Concentric mate in SolidWorks becomes a Concentric joint.
– 一个正交同轴配合转化为同轴副
One Coincident and One Orthogonal Concentric mates in SolidWorks becomes a Revolute joint.
PERPENDICULAR LineLineAng (90 deg.) TANGENT CONCENTRIC TANGENT CONCENTRIC CONCENTRIC PlaneCylTan LineLine LineCylTan LineLine LineLine
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计算机如何进行运动分析？
程序在每一个时间步都应用修正的Newton-Raphson迭代法进 行运算 采用很小的时间步，软件就会预测零件相对于原始条件或当前 时间步的下一个时间步的位置
© 2007 SolidWorks Corp. Confidential.
Plane Plane Plane Plane Cylinder Cylinder Cone Plane Plane Plane Plane Plane Cylinder Cylinder Cylinder Cone Cone
Study of moving systems or mechanisms


运动系统或机构研究
Motion of a system is determined by 运动系统定义：
– Mechanical joints connecting the parts 零件的机械连接 – The mass and inertia properties of the components 部件的质量和惯性特性 – Applied forces to the system (Dynamics) 系统的作用力（动力学） – Driving motions (Motors or Actuators) 驱动运动（运动或致动器） – Time 时间
Degrees of freedom自由度
– Rigid body刚性物体 – Grounded parts固定零件 – Moving parts运动零件
Constraints约束
– Restrictions placed on a part’s movement in specific degrees of freedom
COINCIDENT DISTANCE PARALLEL
LinePlaneDist LinePlaneDist LineLineAng (0 deg.)
PERPENDICULAR LineLineAng (90 deg.) COINCIDENT TANGENT COINCIDENT COINCIDENT DISTANCE ANGLE PARALLEL LineLineDist LineCylTan LineLine PlanePlaneDist PlanePlaneDist LineLineAng LineLineAng (0 deg.)
COSMOSMotion 运动仿真培训
Image courtesy of National Optical Astronomy Observatory, operated by the Association of Universities for Research in Astronomy, under cooperative agreement with the National Science Foundation.
COSMOSFloWorks Flow Simulation
Fatigue
Optimization
COSMOSMotion
Post-dynamics
COSMOSEMS Electromagnetic
© 2007 SolidWorks Corp. Confidential.
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What is Motion Simulation 什么是运动仿真?
– Movement of part(s) under free motion subject to forces
自由运动物体与力作用下的零件运动
– Partially controlled and infinite number of results depending on forces
依赖于力 的部分约束和无限数量的结果
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运动副基础知识（4）
Fixed固定副 Screw螺旋副
移动和旋转轴
螺距
原点
约束3个旋转，3个移动自由度
约束1个自由度
2个构件可以不平行于移动和旋转轴，但2个构件的Z轴 应该平行且方向一致。 15
© 2007 SolidWorks Corp. Confidential.
运动副基础知识（5）
Parallel平行轴 Perpendicular垂直轴
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约束映射
什么是约束映射?

是指在2个指定的零件之间，自动地、智能的将装配关系 转化为最小的机构运动幅的形式。基本的约束类型可以合并为 简单的机构运动幅，例如
e.g. 1 coincident joints becomes a planar joint
2 orthogonal coincident joints becomes a translational joint 3 orthogonal coincident joints becomes a fixed joint 1 Coincident and 1 orthogonal concentric becomes a revolute joint
注: SolidWorks 中 有100多种零件 约束的方式
© 2007 SolidWorks Corp. Confidential.
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Line Line Line Line Line Line Line Plane Plane Plane Plane Plane Plane Cylinder Cylinder Cylinder Cone