-
Mechanics of MachinesMCB 3043
-
Outline of Lecture 1
Course Introduction
Objectives, Instructors, Text, Instruments, Assessment,
Groupings, Labs & Tutorials.
Introduction to Mechanism
Links, Joints, Categories
Kinematic Diagram
-
Course Instructor
1. Dr Setyamartana Parman, 05-3687197, 19-03-06,
[email protected]
2. Dr Dher Mohammed Albarody, 05-3687167, 18-03-**,
[email protected]
3. Dr Abdul Rahim Othman , 05-368****, 17-03-**,
***@petronas.com.my
-
Course Outcomes
By the end of the course, students should be able to
Analyze the kinematics and dynamics of mechanisms found in
common machines.
Design mechanisms to generate simple motions.
Evaluate forces acting throughout a mechanism.
Apply computer tools to aid simple mechanism analysis and
design.
-
Course Text
Machines & Mechanisms
David Myszka;4th Ed, 2013,
Pearson-Prentice Hall
-
Drawing Instruments
Everyone should have these. Required in tutorials, quizzes,
tests and exam.
-
Course Assessment
Freq %
Assignments ~ 9 19
Labs/Project 2/1 10
Tests 3 21
Final Examination 1 50
TOTAL 100
-
Mechanics of Machines MCB3043Semester Sep 2014 Timetable
-
Tutorial
Compulsory
1 hr weekly starting from Week 2
Must bring the drawing instruments to the tutorial starting from
Week 3
Monday or Friday, 10 11.30 am
Week 2 Week 14
At 17-01-07
-
Mechanics of Machines MCB 3043Semester Sep 2014 Lab Schedule
Lab 1: Week 3
Analytical Techniques (Microsoft Excel) [2 hrs]
Lab 2: Week 7
Modelling & Simulation (MSC-ADAMS) [2 hrs]
Venue: Computer Lab 18-02-05
-
Labs & Project
There will be two labs
Completing labs is compulsory for each student. If the students
fail in completing all labs, they are not allowed to take the
project.
Project will be done in groups of 2
The project groups have to presentate/demonstrate their
results.
-
Assignments
There are in-class assignments (Quizzes) and homework
assignments
Quizzes will be conducted during lecture or tutorial
sessions.
Quizzes that require the use of drawing instruments will be
conducted during tutorial.
-
Course Topics
Mechanisms
Position analysis
Mechanism design
Velocity analysis
Acceleration analysis
Cams
Gears
Belts
Static Force
Dynamic Force Analysis
-
Machine & Mechanism
Source of
Power MechanismOutput
Motion
MACHINE
Input
Motion
Limited motion capabilities
(eg fixed speed, direction
and displacement)
Useful motion
as required by
the application
Convert, transmit and direct forces/energy to perform useful
work
Copyright 2004, 2006 by Azman Zainuddin
-
Machine & Mechanism
(Example)
Source of
Power:
Engine
Mechanism: Crank,
timing belt, pulleys,
gearbox, bevel
gears, driveshaft,
wheel
Output
Motion:
Forward
Movement
of Car
CAR
Input
Motion:
Linear
Reciprocati
ng Stroke
of Piston
Copyright 2004, 2006 by Azman Zainuddin
-
Mechanisms
-
Definitions
Machine: A device used to convert, transmit and direct forces or
energy to accomplish a certain objective.
Mechanism: a device used to convert, transmit and direct motion
to
accomplish a certain objective.
a series of links and joints designed to accept an input motion
and produce a useful and desirable output motion.
made up of several bodies (or links) connected by joints.
normally does not include the source of power.
also known as linkage.
A machine might comprises several mechanisms.
-
Components of a Mechanism
Link an individual part of a mechanism. It is a rigid body.
Springs, belts and cables are not links and are ignored in
kinematic analysis.
Joint a connection between two or more links. It allows relative
motion between the links it connected. Also called kinematic pair
or pair
link
joint
-
Categories of Links
Simple Link - A link that has only two nodes, points
on the link where the link can be connected to other links.
(Also called binary link).
Complex Link - A link with more than two nodes.
(Also called ternary link for a three-node link, quartenary link
for a four-node link)
simple link complex link
-
Examples of Links
-
Joints
Revolute Joint
Pin Joint
Pivot Joint
Hinge Joint
Prismatic Joint
Sliding Joint
Piston Joint
R-joint
P-joint
Define relative motion between links
R-Joints and P-Joints are categorized as PRIMARY JOINTS. Most
mechanisms are combinations of only R- and P-joints.
-
Robots with R- and P-Joints
-
Lower & Higher Kinematic Pairs
Lower pairs- Joints with surface contact
Higher pairs- Joints with line or point contact.
e.g Pin in a hole e.g. Pin in a slot
ability to be lubricated
high low
For low wear and long life, always choose lower pairs rather
than higher pairs
-
Other Lower Pairs (besides R- and P-Joints)
-
Higher Pairs
Copyright 2004, 2006 by Azman Zainuddin
-
Summary of Joint Types
Pin rotation (1D)
Sliding translation (1D)
Cylindrical - rotation & translation (2D)
Spherical (or ball/socket) rotation (3D)
Helical (or screw) rotation & translation (1D)
Planar - translation (2D) & rotation (1D)
Cam - rotation & translation (2D)
Gear - rotation & translation (2D)
Lower
Pairs
Higher Pairs
Primary
Joints
-
Point of Interest
A point on a link where the motion is of special interest
point of
interest
It is of interest in the
analysis to determine the
path taken by the end
point as the link is
rotating about one of its
pin joints.
Copyright 2004, 2006 by Azman Zainuddin
Position 2
Position 1
-
Example of a Mechanism
Link
Joint
Link
Link
LinkJoint
Joint
Joint
= Frame
A link might be made up of several different components but all
of them always move together, no relative motion at all against
each other.
Frame a type of link. This link serves as a frame of reference
to other parts of the mechanism. Normally, this link is
stationary.
-
Open Chain vs Closed Chain
All links have at least two joints
At least one link has only one joint.
E.g. robotic arm, backhoe bucket
