|
|
| At: Tutorials | | | | | | | | | |  |
|
About the Gantt Chart (elementary) To Top
I'd like to show you what makes up a Gantt Chart. Here on this whiteboard we have a very simple Gantt Chart named Sample Plan which illustrates the basics. There are 4 important elements in the Gantt Chart; the Timescale, Milestones, Tasks, and Relationships. The Timescale is drawn along the top of the Chart here, moving from left to right. This one is divided into 6 Time Periods, and is labeled Apr, May, Jun, etc. Might be fishing season. Try to see that your Timescale is not restrictive. Your graphic will look better if there is a little space both on the left and on the right. Now this first symbol here is a Milestone, also called an event. The important thing to remember is that a Milestone consumes no time. It has a Duration of 0. The second symbol down here is a Task, also called an Activity. Tasks are the items that accomplish things; that lead to our Milestones. So Tasks do consume time. This Task consumes 2 Time Periods. So it has a Duration of 2. The third type of symbol is a Relationship; also called a Link. This Relationship defines the connections between our Milestones and our Tasks. These Relationships are one of the most important aspects of the Gantt Chart for a couple of reasons. One is that they allow us to make changes in our Chart by just changing our Start date. See, if we moved the Start of this plan from the first of May to the first of June, our Tasks and final Milestone would be pushed out, and show that we expect to finish the first of September. The more important aspect of a Relationship is that it shows the true connection between Tasks. This second Relationship indicates that the 2nd Task cannot start until the First Task finishes. The representation that we have here is commonly known as a 'waterfall' effect. It results from common relationships, and illustrates that we like to think from top left to bottom right as we follow this arrow of time. These numbers down the left side here are the ID number of the Task or Milestone. They are not formally a part of the Gantt Chart. We use those ID numbers in the Help-U-Plan Workspace to identify the individual Tasks and Milestones in the Chart, and we include them when we print the Chart because we have found it is handy in meetings for people to identify Tasks and Milestones by their number. We think it's important to make your Gantt Chart as clean and as simple as possible. It is a deceptively simple-appearing graphic. But it can contain a lot of information. And that of course is the power of the Gantt Chart, and why it can help you communicate your idea or your plan to others. Now there are 2 things to think about when you build a Gantt Chart. One is "What is this going to look like when I print it out?" Typically we create this Chart when we want to make copies of it, hand them out, and communicate to others what we expect to happen. That is why the appearance of the Chart is so important. It needs to be pleasing, and easy to understand, even when someone has never seen this thing before. And that is the power of the Gantt Chart. It makes use of our universal ability to understand the progress of time in terms of left to right, and top to bottom. This is what is called the 'Waterfall Effect', which you can begin to see, even in this simple plan. Now the second thing to think about in building your Gantt Chart is to make it easy to modify when you make changes. That means that wherever you can, you use these relationships to connect Tasks and Milestones, and to place them on the Chart relative to your Timescale. Then when you make a change in the position of this first Milestone, the other items will shift automatically. So don't put a Start on these items unless it's really necessary. Just put a Start on this beginning Milestone, and then your plan will flow according to the Relationships and the Task Durations that you have assigned. Now a number of different types of symbols are used to make a Gantt Chart in different software systems. What we use in Help-U-Plan is a symbol system called 'sticks-and-balls', with this being the 'stick', and these being the 'balls'. We think this results in a pleasing graphic, with the balls emphasizing the beginning and the end of the Task, and the stick connecting the 2. We think it's important to make your Gantt Chart as clean and as simple as possible. It is a deceptively simple-appearing graphic. But it can contain a lot of information. And that of course is the power of the Gantt Chart, and why we think it has such a big future. About the Timescale To Top I want to talk for a minute about the Timescale. Here we are in the Workspace with our common Sample Plan already loaded, and our Timescale is across the top here, from left to right, and showing the months April through November. This Timescale will be the most important item when you define your Gantt Chart, because all of your Milestones and Tasks are shown agains this 'arrow of time'. I'd like you to keep a couple of things in mind when you define your Timescale. First, try to define it so there is a little room left both on the left and the right of your chart. That does 2 things; first, it makes your chart look more attractive, less busy. Secondly, it gives you a little room to maneuver as your plan progresses. Lets you make modifications to your Tasks and Milestones without having to modify your Timescale. The second thing I would like to you keep in mind is that, in Help-U-Plan, these Timescale labels here are simply text. That means they can be whatever you want them to be. To illustrate, let's change one of these labels to something non-sensical, and we'll see that it doesn't change the flow of our Tasks and Milestones at all. So we'll select Plan Settings up here and then select 'Change Main Timescale Labels' down here. Then let's change 'Jul' to 'Pudding'. Then we go back to the Workspace and take a look. See, it didn't change our data at all. Still flows along just as before. So this feature allows you to be creative with your Gantt Chart. These labels could indicate a time period, such as 1650-1700, and 1700-1750. Or we could show that this was the time of Socrates, and Plato, and Aristotle. Whatever you want. Now, you can define your Timescale when you start a new plan (click this button up here); either by starting from scratch, or by using the New Plan Wizard. Or, you can select a pre-defined Timescale by going to the Templates with this button up here. Just as we have Templates of common plans that you can select from this drop-down list, you can select Timescales from this one. Let's say you want a Daily Schedule, beginning with Saturday like this one. Select it, then click this button saying 'Take to the Workspace'. Then we'll have an empty Timescale ready for our own Milestones and Tasks. Remember, as we saw, you can change these Timescale labels at any time. Also, you can add Timescale columns to your Chart as necessary; up to a total of 31. Backward Planning To Top I want you to be aware of the 'backward planning' feature available with Help-U-Plan. Here we are in the Workspace, with a Template using the 'backward planning' mode already loaded. This Template is called 'Grant Application (backward)' 'Backward planning' means that your starting point in constructing the Gantt Chart is to the right; typically a Milestone. We sometimes call this a 'drop-dead' date. With this plan, this is the date that the grant application has to be submitted; here the first of June. You know you have to accomplish certain things before that drop-dead date, and you want to know where you stand today. Do you have plenty of time, or are you already behind? So you start at this drop-dead date, and add Milestones and Tasks that Precede this final Milestone. You work backwards. So with backward planning, our final Milestone typically becomes the controlling item. Let's illustrate what happens to this sequence of events and activities, if the grant application date should get postponed 2 weeks. So let's enter an offset from the existing Start for this final Milestone of .5; that means 1/2 of 1 Time Period. We'll enter the Task ID for that Milestone up here, hit our ENTER key, and our entire Chart shifts to the right like this. Also note that our button here says Precedes, rather than Predecessor. That is because as we add Tasks, they will Precede other Tasks or Milestones. It is a little twist to the Relationship or Link between these items. Remember that You can't change this planning mode once it has been set. Attaching a Graph To Top (available about 8/15/05) I want to show you a feature we believe is only available in Help-U-Plan; that of attaching a graph to a Gantt Chart. Here we are in the Workspace, with a Template already loaded, called Blue Spruce w/graph. I used to work for a wholesale nursery in Oregon that specialized in Blue Spruce. One of our concerns was the buildup of a spider mite population in the trees, because the mites sucked the juices out of the needles, and could simply destroy the tree. So here we show the common activities for taking care of the spruce trees during the primary part of the year. And down here I have attached a graph indicating a physical count of the mites. This was obtained by sampling the fields, shaking the mites out of a bough onto a piece of white paper, and then counting the mites with a hand magnifier. This graph indicates a gradual buildup of mites to a point that justifies spraying, then shows a decline in count as a result of that spraying, then a gradual buildup into fall. At this point, you know a frost is coming which will kill these mites, so there is no concern. Additionally, you could attach another graph which accumulates historical data, so you could see where you were relative to the past. This would be a pretty powerful tool for managing an expensive crop. Keeps you from guessing and making poor decisions. You use the tab named 'Graph', to either add a graph or to modify an existing one. Your graph data points correspond to your Timescale labels, so a graph is fairly easy to attach. We think it can be an important addition to some Gantt Charts. |
|
Email: ronc@helpuplan.com bob@helpuplan.com |
 |
||
© 2001-2008 Help-U-Plan Program. All rights reserved. |
|||