Course Motivation• Learn engineering design by the Systematic Design Process via lectures

and doing a project• Apply Systematic Engineering Design Process on a design project.

“To learn design is to do design”

In doing the design project:• Apply Conceptual Design Methods.• Search and apply information and engineering data

in design of machine elements. Carry out Materials Selection.• Apply PLC Technology in the control of the electro-

hydraulic-mechanical power transmission system. • Produce Engineering Drawings, communicate effectively

design ideas and solutions.• Estimate the Cost of the Prototype using systematic tools.• Finally, submit a Design Report at the end of the semester. 1

2

Course Contents

Ng Heong Wah (NHW)

Ang Hock Eng (AHE)

John Heng (JH)

Zhou Kun (ZK)

•Product Definition•Conceptual Design•Embodiment Design•Detailed Design, Engineering Analysis & Documentation

•Mechanical Power Transmission Systems•Hydraulic And Pneumatic Systems•Cost estimation tools

•Electric Motors And Linear Motion Systems•Programmable Logic Control (PLC) techniques

•Basic engineering materials properties and failure modes•Basic materials selection in design•Effect of component geometry in materials selection

•Do a design project

3

Wk Date Monday,  LT1,  11:30 pm ‐12:30 pm Date Wednesday, LT1,  9:30 ‐11:30 pm1 10/8 National Day Holiday 12/8 Product Definition & Design 

Requirements , Conceptual Design INHW(AHE)

2 17/8 Conceptual Design II NHW 19/8 Embodiment Design I NHW

3 24/8 Embodiment Design II NHW 26/8 Detailed Design I NHW

4 31/8 Engineering Analysis and Documentation

NHW 2/9 Hydraulic systems –sizing & selection

AHE

5 7/9 Hydraulic systems –sizing & selection AHE 9/9 Ladder Logic programming, pneumatic circuits I

JH

6 14/9 Hydraulic circuit design AHE 16/9 Ladder Logic programming, pneumatic circuits  II

JH

7 21/9 Hydraulic circuit design AHE 23/9 Application of PLCs in automated systems  

JH

28/9 28/9 – 2/10 ,  Recess Week 28/9 – 2/10,   Recess Week8 5/10 Cost Estimation I AHE 7/10 Electric Motor drive system design, 

sizing & selection JH

9 12/10 Cost Estimation II AHE 14/10 Electromechanical sensing & actuation components 

JH

10 19/10 Introduction to Materials ZK 21/10 Basics of Materials Selection ZK

11 26/10 Multiple constraints and Conflicting Objectives

ZK 28/10 Selection of Materials and Shape ZK

12 2/11 Selection of Materials and Shape ZK 4/11 Selection of Materials and Shape: Case Studies

ZK

13 9/11 Selection of Materials and Shape: Case Studies

ZK 11/11 Brakes & Clutches AHE

MA4001 – Engineering Design Teaching Plan

John Heng

Week No 1 2 3 4 5 6 7 8 9 10 11 12 13Dates ‐Monday 10/8 17/8 24/8 31/8 7/9 14/9 21/9 5/10 12/10 19/10 26/10 2/11 9/11Project

FreeNoLabs

√ √ √ √ √ √ √ √ √ √ √Tutorials T1 T2 T3 T4 T5 T6 T7 T8 T9 T10Tutorial questions NHW NHW NHW AHE JH JH AHE ZK ZK ‐Concept Presentation

√

Report Submission

√

Final Presentation √

Design Project Schedule  : Tutorials  session ~ about 40 mins.   Project session  ~ Rest of 3 hours             Version : 3

MA4001‐Design Classes Groups No , (Venue‐ Design Lab) – Supervisors 

Mon:  1:30 pm‐4:30 pm MA1‐MA4 ,   4 groups – AHE, NHW, OLS,  ZK

Tues:  1:30 pm‐4:30 pm MA5‐MA7,    3 groups‐ OLS, JH, WMS

Wed:  1:30 pm‐4:30 pm MA8,              1 group ‐ Sridhar

Thurs: 1:30 pm‐4:30 pm MA9‐MA11 , 3 groups‐ SLK, XZ, YWY Ng Heong Wah Ang Hock Eng

Ong Lin Seng Seah Leong Keey

Sridhar Wu Mao See Xiao Zhongmin

Yeong Wai Yee Zhou Kun

5

Do a Design Project:

• Apply knowledge of design processes, costing, materials and machine elements , to design a product

• Project for this semester is:

Design of a Mechanical Car Stacker

Tutorials Project

Lab sessions~40 mins Rest of 3 hrs

6

4 students form a team. All teams will work on same project.

Team level.The marks consist ofmid-semesterpresentation andproject report.

Team receivessame marks.

Your subject grade

Examination 100% Project 100%

Interview 10%Logbook 10%Report 80% + +

50:50

Individual level, Your name in front.contains details of:

sketches, calculations, faxpart data from supplier,info found and anyindependent work,submitted with report.

Individual levelInterview at any time insemester.

Log book required assupport material.

Supervisors look forknowledgeable response.

Course Grading

3. Project Marks

• This project is worth 50% of the course marks for MA4001. The other 50% is from

the course examination paper. The project team will comprise of four members and

individual marks will be allocated according to:

• Individually kept logbook will be inspected by the tutors on a regular basis and

queried. All students are required to fill the log book with details of work done

whether it be sketches, design calculations, internet search and any other work that

they personally conducted for the project relevant to the design development.

Phone calls, faxes of product or part data from suppliers can be stapled to pages in

the log book. Therefore, no two log books should contain the same information.

• Each logbook will have the student's name written on the cover in ink. An exercise

book or notebook at least A5 size is suitable. They will be submitted with the group

project report at the end of the project.

3.1 Formal Presentation and Interview

• The presentation and interview are important milestones in the project.

• Every team member will have to present to the lab group at the middle semester

and be interviewed at the end of semester.

• For the presentation, each team will prepare a short oral discussion of the project

concepts.

• The interview will be between the tutor and the team and will consist of questions

to individual team members concerning their individual involvement in the project.

• Their log books will be shown to the tutor as support material.

• Interview will be spread over the two to three lab sessions, with tutors deciding

on interview timings, generally at each week sessions, he will interview two to

three teams.

Marking Scheme: The total mark of 100% is distributed as follows:Team level 80% : Report - 70% based on:• Design process {appreciation of task, design specification}.• Range, quality and number of solutions {number, feasibility, simplicity,

practicability of solutions}.• Use of matrix selection method and range of criteria}.• Development of layout and embodiment.• Detail design of machine elements. Quality and effectiveness of sketches and

drawings.• Appropriate selection of engineering materials and stress analysis .• Selection of electromechanical sensing & actuation components,

Programmable logic control. Performance and cost estimation

Presentation - 10% based on:• Clarity of design concepts and explanations. Quality sketches.

Individual level 20%• Logbook-10% : Regular, thorough and clearly documented record of design

work and organization throughout project.• Interview-10% : Knowledgeable technical response to queries.

Overall coherence between team members.

10

•It is a responsibility for an engineer to record ideas and results of

his/her work in a log book.

•As a student of engineering, you should learn the art of good record

keeping and develop good documentation habits.

•Enter everything into your logbook directly, so that it is a running

record of your project as it develops.

•Do not write things down on bits of paper and copy onto the log book neatly.

•Ideas, calculations, sketches, relevant pages of catalogues, design

parameters, dimensions, schematics, graphs, reminders etc. are entered.

•Do not tear pages, cross out the page diagonally.

•Always bring your log book to your design classes.

Keeping a Design Log Book

11

Pages from a Student’s Design Log Book

Design of a Mechanical Car Stacker

• The worldwide population of cars is increasing at an accelerating rate. Expressways are becoming increasingly choked at peak commuting periods and parking has become an increasing problem at residences and workplaces.

• In many cities, high population density, scarcity and high cost of land resulted in innovative automated car parking systems. These can range from small 2 to 3 cars stacking systems to warehouse sized systems storing hundreds of cars in a space efficient manner.

• The largest systems are completely automated using warehouse storage and retrieval technologies and reliant on software controlling the system.

• Extensive use of computerised tracking and sensors allows the driver to deposit a car at the apron, swipe a magnetic card and the system will remove the car and park it deep within the warehouse.

• On his return, he simply swipes the card again and the car is returned to him undamaged and in less than a minute. See an example in figure 1.

• This design project also expects you to solve the problem of car parking.

• The objective of is to design a simple system capable of parking 2 to 3 cars on a footprint of single parking lot based on a mechanical system.

• The mechanical system is unlike the completely automated system described above. The mechanical system car park is a method of parking that involves a person such as a car park attendant or driver to initiate the mechanical movements via electrical push buttons/switches etc.

• The mechanical movements are generated by electric motors driving machine elements such as power screws, rack and pinions, chains, wire ropes, pulleys and hydraulic actuators.

www.totalparkingsolutions.co.ukwww.wohr.parking.ukwww.carstackers.com.auwww.hardingsteel.comwww.ronblank.com/courses/kmp14a/kmp14a.pdf

information available in internet search :

• Software is not needed as in a mechanical system. Although small and simple,

the mechanical system can be replicated or multiplied over and over to cover a

large parking lot in a conventional car park ramp below a office building, condo

or open air car park, i.e. it has to be modular. Therefore you need to design just

the modular unit and not the entire car park.

You can start with the premise that the development is starting from

scratch, so you have a free hand in designing a high density parking system in:

• a new office development,

• a open air car park,

• a residential condominium pr

• an industrial estate

• Depending on each, the constraints are different and have to be included in the

design of the car park. So choose one of the above.

1.1 What are the design requirements?

The first stage of design involves writing down the design requirements. These

are concise statements specifying what the designed product has to achieve and

to what degree that achievement must be attained (i.e. its importance level) for the

product to be successful. The statements should state quantifiable parameters if

possibly (i.e. the constraints). Here are some examples:

For the car stacker to be a success, it should be able to hold as many types of

cars as possible, from small cars of 1 litre engine capacity to the largest Sports

Utility Vehicles (SUV) or Multi Purpose Vehicles (MPV) or even transit vans.

The latter are typically heavier, much taller and longer. However it might not be

necessary to cater for transit vans in a condo development, in fact, they can be

barred by specifying a volumetric and weight limitation.

This gives rise to 2 requirements:

1.1 What are the design requirements?

The maximum capacity for storage for standard cars shall be 2.2m wide and 6m

long with a minimum clear height of 1.8m. (note that MPV require a min. height

of 2.0m).The machinery shall be capable of handling a maximum weight of

20 000 N. per vehicle.

Other design requirements you should consider are safety, aesthetics, delay

times etc and many more. In the design requirements, one should not specify

“how” i.e the technology needed to satisfy the requirements.

As such statement like; “A hydraulic actuator capable of lifting

20 000N is to be used” is not a design requirement since other types of machines (examples being winches, hoists) are as capable of this task.

A Note to Design Stream students doing this project.

Nowhere is aesthetics and human factors design more important than in the car stacker. Much effort is needed to put an acceptable face to the machinery so it does not look dirty, rusty and overly functional without form.

1.2 Hydraulic or mechanical methods?

• Although, the hydraulic process seems to be the more popular, mechanical methods such as by kinematic mechanisms, rack and pinion or power screw drives are equally suitable.

• The prime energy source will be an electric motor as the initial drive, further converted by a hydraulic pump to pressurize oil for actuating the hydraulic cylinders in the case of hydraulic process.

• Electric motors are suited to drive gear trains to transmit power to the machine elements in the mechanical process.

• Use the knowledge of machine elements from your MA3001 courses and engineering graphics from your MA2005 courses to innovate ways of moving the car.

1.3 The movement

The design project requires an exploration of the alternatives to the conventional.

A better solution to the design is to be sought rather than fine tuning the conventional design.

Think in 3 dimensions, there are a total of six degrees of freedom to move a car, i.e. linearly in 3 directions X,Y and Z and rotates about the Z, Y and Z axes.

The systems may consist of the following primary components to assist in the movement:

• Carrier or pallet or shuttle is the base transporting the car horizontally in two dimensions X and Y.

• A lift is the transport device used for vertical Z movements.

• A turntable is for rotating the car around the horizontal plane.

• Rack or framework is the supporting structure for the parking system, providing for storage, machinery for transport and safety for the user.

The following figures shows some interesting movement used in commercial systems. Use these as a means to generate ideas.

However the machinery are not shown, it needs to be designed in detail in your project.

1.5 Structural framework of the car stacker

• The structural frame supporting the cars, hydraulic or mechanical systems need

to be strong and stiff in order to function reliably. Moving parts need well

lubricated guides or rollers. The supporting frame must also ensure all the

moving part of the machine elements remain in alignment and large deformation

(even elastic) does not affect the functioning of the device. Strength of materials

calculations are required to confirm the strength of the frame members. You

need to carry out design calculations to ensure that your structural supports are

within the design stresses as well as the deflections are within tolerances.

• It is advisable to apply embodiment principles to the design of the structural

frames to improve on the efficiency and reliability of the frame. Reinforcement

and strengthening enables reduction in weight and economy in use of material.

Flat steel plates used without reinforcement will be excessively thick in order to

resist bending deformation or buckling failure. With stiffeners and corrugations,

thinner plates can be used. Beam to beam connections are strengthened against

bending modes by web reinforcement

Project Objectives:

• To design a car stacker for parking and storing multiple cars (2 to 3) on the footprint of a typical car park slot utilizing either the aboveground and/or underground space.

• To conduct a literature survey of the available mechanical car stacker system in the market and patents disclosed of related inventions in the field.

• Discuss the available design and write a critique ( for example discussing the pros and cons of the concept as shown in fig 2.)

• To develop the design requirements.

• To generate a number of concepts (3) to perform the functions required. Innovative and creative design is expected.

• To select the best of the 3 design concepts using concept selection methods.

• All the above supported by structural framework of steel beams and plates construction shown to be capable of withstanding all anticipated loadings.

• For the best design, to design in detail the mechanisms to transport the car from parking position into the stacker, and in reverse return the car to the same parking position.

• Design may use either mechanical or hydraulic power transmission. For hydraulic process, the hydraulic pump, control valves and relevant accessories must be specified and included in the design. The source of power will either be an electric motor/s. The car stacker use the machine elements/components where-ever it is appropriate to the design; namely:

• Bearings

• Belts and pulleys

• Brakes and clutches

• Cables and wire ropes

• Chains and sprockets

• Hydraulic cylinders

• Gears and shafts

• Kinematic mechanisms

• Rollers and wheels

• Springs, pins, keyways, couplings and keys.

2.1 Learning objectivesIn carrying out this project, students working as a team will use the tools learnt from the lectures to undertake the following;

• Perform product definition and generate needs assessment and product requirements.

• Understand that the needs assessment will be used to create a set of criteria and weighting factors to evaluate design concepts.

• Build up a number of uniquely different design concepts using brainstorming and other appropriate creative processes.

• Use the structured matrix method for evaluating the design concepts with respect to the selection criteria to finally select the most suitable concept.

• Be able to develop the concept further by appropriate layout and embodiment procedure.

• Become familiar and can apply machine elements to create suitable actions of the mechanical car stacker and select the most suitable noting its advantages over other elements

2.1 Learning objectives• Become familiar with the loading analysis and strength of materials calculations and

the selection of approximate dimensions of machine elements to adequately sustain the applied loads within the factor of safety.

• Become familiar with the selection procedures for some off-the-shelf machine elements and use of parts catalogues in the product.

• Be able to draw conceptual sketches and part drawings to drafting standards using CAD programs or by manual drawings.

• Carry out detailed stress analysis and material selection process.

• Conduct a cost estimation of the mechanical car stacker system.

• Demonstrate a high level of confidence and enthusiasm in the stacker and sal ability in the market place.

• Be able to present a competent, professionally presented technical report starting from the product definition, conceptual design and the development of the embodiment to the final design calculations with good quality drawings.

31

This is quite a challenging project, but do not worry. There are systematic steps to proceed with the design which is the course content taught by the lecturers.

•The steps:

1. Define and understand the problem

2. Conceptualise solutions, how many ways can it be done?

3. Embodiment design improve and make more effective the solution concepts, Also make the design more manufacturable.

4. Detail design –Produce drawings and instructions on manufacturing a prototype.

How to start

Systematic Design Approach

Important steps of the process, make sure the team follows the structured approach,

• Analyze and redefine the project idea, learn as much as possible by

discussion and information search about the problems and redefine in

team’s own terms .

• Define the project brief in abstract terms.

• Determine the customer needs and potential markets.

• Create good product specifications or requirements.

• Generate many concepts solutions, use techniques such as brain storming

to generate large number of solutions.

• Generate detailed layouts of the main functions and other auxiliary

functions.

• Generate detailed designs of the parts. & Modify designs as necessary.

• Use the segmentation techniques where possible (Function Analysis

Diagram) to break up problem into smaller easy to handle parts.

• Analyze proposed solutions and use relatively rapid means (solution

screening), first order analysis to reduce the number of solutions.

• Make sure there are some good (minimum of 3) solution concepts.

• Generate specification specific to the solution concepts and make use of

the product specifications as selection criteria of the decision matrix

selection method.

• Select one solution using decision matrix method. Create a simple layout

of main functions using embodiment principles.

34

For use in your project report.

Product Picture

Student names and photo

Design Report front page

Design for Mechanical Car Stacker

Report to be submitted by Week 13 (9th Nov to 13th Nov)

35

Title page: Title of project, authors and group number (with photos)-(Have a pictorial view of your own design on the front like in this document)

Chapter 1: Introduction –Give reasons for the designing this product, research and survey on existing design and systems, design requirements list, quantifiable parameters.

Chapter 2: Conceptual Design - Contains the function analysis chart, morphological chart and many hand drawn sketches of alternative conceptual designs. Selection of best design using matrix selection method.

Chapter 3: Embodiment (Layout) Design - Contains alternative layout or embodiment of critical components so that more robust and effective design are obtained.

Chapter 4: Electrical System Design (if any)-Selection, design of electromechanical sensing and actuation components. Use of digital control technique and microcomputer programming

Structure of the Report

36

.Chapter 5: Detailed Design and Material Selection

– Mainly contains calculations and detailed assembly and partdrawings. Calculations on selection of main machine elementsand strength of materials sizing of major parts only. Although CADdrawings are preferred, hand drawn part drawings are acceptedprovided the relevant manufacturing and dimensional informationare shown. Must provide an assembly drawing showing how theparts are put together.

Chapter 6: Cost Estimation-Estimate the total cost of 1 prototype using product explosiondiagram. Discuss and include the direct and indirect cost.

Chapter 7: Conclusions- Give a short account of major achievements of the design andproblems encountered.

References -Books, references, data sources and URLs of internet websites

Appendices: - Relevant tables or catalogues pages where the off-the-shelfmachines element parts were selected.

Structure of the Report

37

.

Everybody is ignorant. Only on different subjects.

- Will Rogers

• Co-operation is better than competition.

• Meet the challenge together.

• You get more out of working as a team than alone.

• No formal group leaders.

• Handle your own interpersonal dynamics.

• Team ownership of the design problem.

Work as a Team

38

A problem adequately stated is a problem well on its way to being solved.

- R. Buckminster Fuller

Have many design solutionsThe best way to have good ideas is to have lots of ideas.

- Linus Pauling

Research the internetIn the field of observation, chance favours the prepared mind.

- Louis PasteurWork hardI find that the harder I work, the more luck I seem to have.

- Thomas Jefferson

Understand your design problem

39

Meet your supervisor at the Design Office to start on the project next week. Form your teams and try develop Design Requirements of the project

Prepare yourself:

Explore the design problem

Setting up your design requirements

Research the internet –Don’t copy, improve and innovate

Think of solutions

Next Week

40

Form must be filled one week before the recess and handed to your supervisor.The purpose is to discover interpersonal problems between teams early and to correct them before it is too late.

Peer Review Form

Importance of Engineering Design Process

41

• The real key to world –competitive product lies in high-quality product design.

• Decisions made in the design process cost very little in terms of the overall product cost

but have a major effect on the cost of the product.

• You cannot compensate in manufacturing for defects introduced in the design phase.

• The design process should be conducted so as to develop quality, cost-competitive

products in the shortest time possible.

4C’s of Design

• Creativity• Complexity• Choice• Compromise

Interrelations of Design, Materials, and Processing to Produce a Product

42

An incorrectly chosen material can lead not only to part failure but also to excessive life-cycle cost.

At the concept level of design, essentially all materials and processes are considered in broad detail.

The materials selection charts and methodology developed by Ashby are highly appropriate at this stage.

Depending on the importance of the part, materials properties may need to be known to a high level of precision.

Material and process selection is a progressive process of narrowing from a large universe of possibilities to a specific material and process.

Relation of Materials Selection to Design

Materials are selected on the basis

for four general criteria:

Performance characteristics

(properties)

Processing (manufacturing)

characteristics

Environmental profile

General Criteria for Selection

Materials Selection in Embodiment Design

43

Computer-Aided Engineering (CAE)

44

The advent of plentiful computing has produced a major change in the way engineering design is practiced.

Advantages of Computer-Aided Engineering:Automated engineering drawing in two dimensionsThree dimensional modelingFinite Element Modeling (FEM)Rapid prototypingDesign optimizationComputer-Aided Design (CAD) Computer-Aided Manufacturing (CAM)

A code is a collection of laws and rules that assists a government agency in meeting its obligation to protect the general welfare by preventing damage to property or injury or loss of life to persons.

A standard is a generally agreed-upon set of procedures, criteria, dimensions, materials, or parts.

Designing To Codes And Standards

Chief Aspects of Designing To Codes and Standards:

•Efficiency•Safety•Interchangeability •Compatibility

Complete Engineering Drawings

• A major task in the detail design phase is to complete the engineering drawings.

• Drawings of individual parts are usually called detail drawings.• Detail drawings show the geometric features, dimensions, and tolerances

of the parts. • Assembly drawings show how the parts are put together to create the

product or system.

45

It is necessary to complete these activities before the design can be complete. Complete the Selection and Sizing of Components

Detail design is the phase where all of the details are brought together, all decisions are finalized, and a decision is made by management to release the design for production.

Detail design is the lowest level in the hierarchy of design abstraction. Detail design is a very specific and concrete activity. Poor detail design can ruin a brilliant design concept and lead to

manufacturing defects, high costs, and poor reliability in service. THE REVERSE IS NOT TRUE!

Detail Drawing of a Lever

46Engineering Drawings: The information on a detail drawing includes: Standard view of orthogonal projection; Auxiliary views; Dimensions; Tolerances; Material specification; Manufacturing details. Design layouts show the spatial relationships of all components in the assembled product (the system).

Exploded Assembly Drawing: Gear Reducer

47Assembly drawings are created in detail design as tools for passing design intent to the production department.

Final Cost Estimate• The detail drawings allow the determination of final cost estimates, since

knowledge of the material, the dimensions, tolerances, and finish of each part are needed to determine manufacturing cost.

• Cost analysis also needs specific information about the particular machines and process steps that will be used to make each part.

• Note: Cost estimates will have been made at each step of the product design process with successively smaller margins for error.

48

Prepare Design Project Report

A design project report usually is written at the conclusion of a project to describe the tasks undertaken and to discuss the design in detail.

A design project report is a vital document for passing on design know-how to a subsequent design team engages in a product redesign project.

A design project report may be an important document if the product becomes involved in either product liability or patent litigation.

Cost evaluation

• An engineering design is not complete until we have a good idea of the cost required

to build the design or manufacture the product.

• Among functionally equivalent alternatives, the lowest cost design will be successful

in a free market place.

• Understanding the elements that make up cost is vital because competition between

companies and between nations is fiercer than ever.

• Maintaining market requires a detailed knowledge of cost and an understanding of

how new technology can lower costs.

• Decisions made in the design process commit 70 to 80 percent of the cost of a

product.

• It is in the conceptual and embodiment design stages that a majority of the costs are

locked into the product.

49

1

Primary energy (‘fuel’)

Prime Movers

(‘engines’)

Secondary Movers Power Transmissions

Motors Actuators Fixed Ratio Variable Ratio

Coal Steam turbine Electric motors Fluid cylinders Mechanical

couplingMechanical Coupling

(some)

Oil I/C engine Fluid motors Fluid actuators Clutch Clutch (some)

Gas Gas turbine Fluid coupling Fluid coupling (some)

Hydroelectric Electromagnetic coupling

Electromagnetic coupling (some)

Nuclear Belt Gearboxes

Oceanographic Chain Belt drives (some)

Terrestrial Gears

Power TransmitterPower Converter

Primemover

ComponentNo. 1 LoadComponent

No. 2

M-1 I-2 2-L

Power Source Power Sink

2

600))(( lpmbarkw

V PP MMG

QI

I Q

DC Electrical Drive (Ward Leonard Drive) Hydrostatic Drive

Typical Drives ( or transmissions)

ii

ii

Characteristic Power Parameters

Type of Power Watts

Potential Parameter

Flow Parameter

Mechanical (linear) : N x m/s Force ,N Velocity, m/sMechanical (Rotary) : Nm x rad/s Torque, Nm Angular Velocity, rad/sHydraulic : Head, bar Discharge, litres/minElectrical: I x V Voltage, V Current, I

Fluid Power Control

Input power (kW)

Output power (kW)

PressureControlValves

DirectionalControlValves

FlowControlValvesmotor Pump

Path of power transmission and power modification

Power actuatorsControl valvesPower source

Linear actuator

rotary actuator

motor Pump

Classification of Selected Electric Motors

AC Motors

AC/DC Motors

SPECIAL Motors

DC Motors

Single-phase induction

Three-phaseSynchronous

InductionRepulsionstart

Squirrel-Cage

Universal

Synchronous

―Split-phase―Capacitor start―Capacitor motor―Permanent split-capacitor (PSC)―Shaded-pole

―Squirrel-cage―Wound-rotor

415 ~ 440v

―Permanent Magnet

―Shunt―Series―Compound

Separately excited

220 ~ 240v

―Permanent Magnet―Variable Reluctance―Hybrid

Servomotors

Stepper Motor

DC Brushless

Self excited

Good Energy Management – Entire motor load system be evaluated to minimize energy waste

NEMA publication, MG10- makes the following recommendation

1. Motor Ratings

2. Application Analysis

3. Process and Machinery

4. First Cost versus Long range energy cost

(heat)

Motor Efficiency → 90.5%

Mechanical Load – Torque Speed CharacteristicsTorque in %

Power

100% =

= 100% Constant Torque,

Constant HP

Speed in %

P =

1 .

TRated

T .

NSync

N .Torque-speed characteristics1. Constant Torque (Traction Load) ---- conveyors, crane hoist systems2. Torque α to speed (laminar flow load) – viscous friction, magnetic brakes3. Toque inversely α to speed (traction load) – constant horse power loads4. Torque α to square of speed (turbulent flow) – centrifugal pumps, fans & blowers

1

2

3

4

Source: J.L.Meriam , L.G.Kraige, Engineering Mechanics – Statics,Dynamics

Source: J.L.Meriam , L.G.Kraige, Engineering Mechanics –Statics, Dynamics

Source: J.L.Meriam , L.G.Kraige

Source: J.L.Meriam , L.G.Kraige, Engineering Mechanics- Statics, Dynamics