Upload
kate-langwell
View
219
Download
0
Tags:
Embed Size (px)
Citation preview
Project Management Tools
Stephanie SchmitJune 24, 2013
Source: Project Engineering ESD.062 / Oliver de Weck
ESD.052 Project Engineering Page 2
Methods and Tools you will learn
3
Work breakdown structure Task List Scheduling and Gantt Charts: Critical Path Method
Tasks are the building blocks of projects
Project = set of related tasks
4
Work Breakdown Structure (WBS)
Used to create the task (job) list Tree-decomposition of project tasks WBS identifies “terminal elements” The key starting point for project planning Required by contracts as part of the SOW Can be activity-oriented or deliverable-
oriented Use “sticky-notes” method early on
Carl L. Pritchard. Nuts and Bolts Series 1: How to Build a Work Breakdown Structure. ISBN 1890367125
Job A Job X Job GJob B
Example Work Breakdown Structure
5
HumLog DC Project
1 Planning 2 Contracting 3 Staffing 4 Construction 5 Commissioning
1.1 LocationAnalysis
1.2CapacityModeling
1.3TransportationAnalysis
2.1GovernmentApproval
2.2Request forProposal
2.3 EvaluateProposals
2.4Select MainContractor
2.5Finalize Contract
4.1Site Preparation
4.2Dig and PourFoundation
4.3Erect MainStructure
4.4Install BuildingSystems
4.5Install Security Systems
…
3.1Staffing forOperations
3.2Staff TrainingAnd Instruction
5.1Stock UpInitial Inventory
5.2Commissioning And Test
5.3Final AcceptanceIOC
6
Discussion Point
Why is it difficult to come up with a good WBS (task list, task structure) in a complex project? Not all tasks known ahead of time if
completely new product/system Others…?
7
WBS Guidelines No more than 100-200 terminal elements,
if more use subprojects Can be up to 3-4 Levels deep Not more than 5-9 jobs at one level
Human cognitive “bandwidth” only 3 bits=23=8 Short term memory for most people 5-9 items Poorer planning if “too-fine grained” – dilution
of attention The more tasks there are, the more intricate
dependencies there will be to keep track of Jobs should be of similar size/complexity Manageable chunks sense of progress Level of graininess very difficult to
answer
8
Task List List all tasks in a table with
Identifying symbol (tag, ID number) Task description Immediate prerequisite jobs (predecessors) Expected task duration
Arrange jobs in “technological order” No job appears in the list until all its
predecessors have been listed Iterations are NOT allowed “cycle error” Job a precedes b precedes c precedes a
Task List – HumLog DC Project
9
ID WBS Task Description Predecessor Duration (wks)
1 Start – Project Kickoff 0
2 1.1 Location Decision 1 4
3 1.2 Capacity Modeling 2 2
4 1.3 Transportation Analysis 2 2
5 2.1 Obtain Government Approval 3 8
6 2.2 Request for Proposal 4,5 4
7 2.3 Evaluate Proposals 6 2
8 2.4 Select Main Contractor 7 1
9 2.5 Finalize Main Construction Contract/Negotiations
8 2
10 4.1 Site Preparation 9 2
11 4.2 Dig and Pour Foundation 10 3
12 4.3 Erect Main Structure 11 4
13 3.1 Staffing for Operations 9 6
14 4.4 Install Building Systems (Electrical) 12 2
15 4.5 Install Safety and Security Systems 14 2
16 4.6 Install Inventory Management System (RFID) 14 2
17 4.7 Install Communications System 14 1
18 5.1 Stock Up on Initial Inventory 15, 16 3
19 3.2 Staff Training and Instruction 13 1
20 5.2 Commissioning and Test 19, 18, 17 4
21 5.3 Final Acceptance and IOC 20 1
22 End – Project Finish 21 0
10
Gantt Charts Attributed to Henry Gantt – most popular PM tool
(80%) Used to plan big shipbuilding projects (cargo ships
WWI) Graphical way of showing task durations, project
schedule Does not explicitly show relationships between
tasks Limited use for project tracking Easy to understand
Bus Unit Project % Start FinishProject "XYZ" 30 9-Sep-03 6-Oct-03
Mkt Customer Clinic 100 09-Sep-2003 12-Sep-2003Sys Requirements Definition 100 11-Sep-2003 15-Sep-2003Eng Parts Design 50 15-Sep-2003 22-Sep-2003Sys Design Review 0 23-Sep-2003 23-Sep-2003Mfg Manufacturing 0 24-Sep-2003 05-Oct-2003Sys Product Release 0 06-Oct-2003 06-Oct-2003
08 Sep'03
08/09 15/09
06 Oct'03
06/10 13/10
22 Sep'03
22/09 29/09
milestone
calendar
tasks
Gantt Chart Builder System (Excel) 1.6
completion
actual
today
plannedD
11
CPM Assumptions
Project consists of a collection of well defined tasks (jobs)
Project ends when all jobs completed Jobs may be started and stopped
independently of each other within a given sequence (no “continuous-flow” processes)
Jobs are ordered “technological sequence”
12
Critical Path CP is the “bottleneck route” Shortening or lengthening tasks on the critical
path directly affects project finish Duration of “non-critical” tasks is irrelevant “Crashing” all jobs is ineffective, focus on the few
% of jobs that are on the CP “Crashing” tasks can shift the CP to a different
task Shortening tasks – technical and economical
challenge How can it be done?
Previously non-critical tasks can become critical Lengthening of non-critical tasks can also shift
the critical path
13
Discussion Point
What is the usefulness of knowing the Critical Path in a project? Tells which task to shorten to finish
project earlier. Others …?
14
Latest Start and Finish Times
Set target finish time for project: T >= F
Usually target is a specific calendar date, e.g. October 1, 2010
When is the latest date the project can be started?
Late Finish (LF) - latest time a job can be finished, without delaying the project beyond its target time (T)
Late Start: LS = LF-t
15
Slack Some tasks have ES=LS --> no slack Total Slack of a task TS=LS-ES Maximum amount of time a task may be
delayed beyond its early start without delaying project completion
Slack time is precious … managerial freedom, don’t squander it unnecessarily
e.g. resource, work load smoothing When T=F then all critical tasks have TS=0 At least one path from Start->Finish with critical
jobs only When T>F, then all critical jobs have TS=T-F
Example Gantt Chart
Goal: Complete big project by deadline!
Build part A(3 days)
Build part B
(2 days)Build part C
(6 days)
time
Assemble part AB
(5 days)
now
Finish(2
days)
16
Deadline15 days away
Example Gantt Chart
Goal: Complete big project by deadline!
Build part A(3 days)
Build part B
(2 days)Build part C
(6 days)
time
Assemble part AB
(5 days)
Critical Path = 10Float time = 5
now
Finish(2
days)
17
Deadline15 days away
7 days later…
DeadlineNow 8 days away
Critical Path = 8 daysFloat time = 0 days
Build part A(3 days)
Build part B
(2 days)
Build part C(6 days)
time
Assemble part AB
(5 days)
now
Finish(2
days)
Finished
Critical Path
No more float time! 18
Example Gantt Chart
19
Main CPM Errors that people make
Estimated job times are wrong Predecessor relationships may contain cycles
“cycle error” List of prerequisites contains more than the
immediate predecessors, e.g. 12, 23 and 1,23
Overlooked some predecessor relationships Some predecessor relationships may be listed
that are spurious and …. Some tasks/jobs may be missing !!!
20
Summary
Work breakdown structure Task List Scheduling and Gantt Charts: Critical
Path Method