Kinematics and Dynamics of Machines MECE 3380

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Kinematics and Dynamics of MachinesMECE 3380

• Bob Freeman
• 10/13/03

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ABET Syllabus

• COURSE OBJECTIVES
• Master the fundamental concepts of
• kinematic and dynamic analysis of 1-DOF planar
  mechanisms,
• kinematic synthesis of 4Bar linkages,
• and general parametric design and optimization.
• Understand that the mathematical models used for
  analysis are also used for design.
• Effective use of math and engineering software
  (e.g., MathCad and Working Model 2D) for
  analysis, simulation, and design of planar
  machines.

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Topics Subject (of 50 min. lectures)

• Fundamental concepts including joint and link
  types, mobility, classification, and equivalent
  diagrams - 4
• Survey of simple mechanical devices including
  gears (simple, compound, and epicyclic), cams,
  friction drives, and differentials - 6
• Design theory and methodology (as applied to
  gears) - 4
• Dimensional synthesis of planar 4Bar linkages - 9
• 4R 4Bar Analysis including position, velocity,
  acceleration, and force analysis, and shaking
  force and moment balancing - 5
• Kinematic-Influence-Coefficient based Dynamic
  modeling of 1DOF planar machines - 6
• DYAD based planar mechanism analysis including
  structural formulation, position, velocity,
  acceleration, and force analysis, and dynamic
  modeling - 8
• Use of MathCad and Working Model 2D (Web-based
  tutorials) 0
• Extend to include use of Working Model 3D and
  MatLab

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COURSE OUTCOMES AND (ASSESSMENT) Introduction to
Parametric Design Optimization

• Classify planar linkages in terms of their name,
  DOF, and equivalent kinematic diagram. (HT)
• Perform kinematic analysis of simple mechanical
  devices including simple, compound, and
  epicyclic gears, cams, friction drives, and
  differentials. (HT)
• This is to be accomplished by "hand", by creating
  and using MathCad scripts, and by using Working
  Model 2D.
• Perform parametric design (including
  optimization) of gear trains and friction drives
  with respect to desired kinematic performance,
  cost, and availability criteria. (HT)
• This is to be accomplished by "hand" and by
  creating and using MathCad scripts.

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COURSE OUTCOMES AND (ASSESSMENT)Dimensional
Synthesis of 4-Bar Linkages

• Type Synthesis Determine whether or not a
  specified linkage type is geometrically
  sufficient to satisfy specific kinematic
  structural and performance requirements, and if
  so, to determine in general how many solutions
  exist. (HT)
• Dimensionally synthesize planar 4Bar linkages
  (4R, Sl-Cr, Inv.Sl-Cr) for
• coplanar motion synthesis,
• angular coordination of a 2-link chain,
• angular coordination of 2 cranks,
• coordination of a slider/piston and a crank,
• and path coordination with a crank.
• This is to be accomplished by "hand" and by
  creating and using MathCad scripts. (HTP)

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COURSE OUTCOMES AND (ASSESSMENT) 4R-4Bar Analysis

• Analyze 4Bar linkages with respect to position,
  velocity, acceleration, and force.
• This is to be accomplished by "hand", by creating
  and using MathCad scripts, and by using Working
  Model 2D. (HTP)
• Shaking-Force balance 4R-4Bars. (H)
• Create a dynamic model of a 4Bar.
• This is to be accomplished by "hand" and by
  creating and using MathCad scripts. (HTP)

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COURSE OUTCOMES AND (ASSESSMENT)General 1-DOF
Planar Linkages

• Perform position, velocity, acceleration, and
  force analysis of general 1DOF planar linkages
  using DYAD structure groups. (HT)
• Create a dynamic model of general 1DOF planar
  linkages. (H)
• Write DYAD-based Mathcad sub-routines to model
  and analyze general 1 DOF planar mechanisms. (H)
• Use Working Model 2D to create and dynamically
  simulate general planar mechanisms. (H)

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CONTRIBUTION OF COURSE OUTCOMES TO DEPARTMENT
OUTCOMES
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Approach

• The students must want to learn the software and
  use the tutorial materials.
• First, hook them with the utility of the software
  to solve problems and understand concepts through
  in-class demonstrations.
• Then, teach them the software in easily
  digestible bites using asynchronous tutorial
  materials that coincide with course assignments.
• After being introduced to the basics, students
  are both more likely and more able to use the
  softwares own more encyclopedic materials.

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Enabling Technology

• TechSmiths Camtasia Screen capture with Audio
• Easy to use
• Excellent editing features
• Reasonable file size Roughly 3MB per minute

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Lecture Summaries

• Condensed summaries of each lecture are posted on
  the course web-site with links to additional
  asynchronous tutorial material as appropriate.

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Example Homework Assignment
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Project Overview

• Student teams to propose a task that can be
  solved using a 4-Bar linkage.
• Two (or more) different kinematic solutions
  required.
• Use Mathcad to obtain analytic solutions, and
  then Working Model 2D to "virtually" verify the
  solutions.
• Perform a dynamic analysis on one of the
  solutions in one position (state) by hand and
  with Mathcad.
• Use WM2D to dynamically simulate the mechanism
  and compare link accelerations, joint reaction
  forces, and required motor torque with Mathcad
  results.
• Compare their two kinematic solutions dynamically
  using WM2D under realistic operating conditions
  for their task and select one as their "optimal"
  design based on some dynamic metric.

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Sample Project

• The example project discusses a solution to the
  general task of controlling the motion of a box
  top.
• Mathcad Script
• WM Tutorial

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Questions!!!

• Keep KD as a required course?
• Replace KD with Modeling?
• Replace 2nd Chemistry / Physics Elective with
  Modeling?