A-1. Chapter 1. Project planning. Chapter 1. Festo Didactic Mechatronics

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1 A-1 Project planning

2 A-2 Mechatronics specialists are responsible for the complete service life of an industrial machine, from the initial planning phase through to its disassembly and disposal. This cycle is illustrated in the chart below. The individual sections correspond to the fields of activity of the mechatronics specialist: Fig. 1.1 Special attention must be devoted to the planning and design process as it forms the basis for all of the following phases. In other words, it determines the machine down times caused by specific faults, the speed at which the faults can be found, the degree of difficulty in obtaining replacement parts, or the nature of the required optimisation phases. Many machines and lines are developed to meet customer requirements and are thus unique. Mechatronics Festo Didactic

3 A-3 A project is by definition a unique new undertaking, characterised by a specific goal, a particular organisational form, or a set of terms pertaining to its contents, time frame, or costs. It generally involves a highly complex sequence of events and the interaction of a variety of activities performed by persons with a wide range of professional backgrounds, problem-solving approaches and interests. This complexity places special demands on the organisation, planning and management of projects. Definition of terms: Project Despite the unique nature of a specific machine, a project for the development of a line essentially always involves the same phases: development of ideas definition of design specifications planning and design assembly and installation of the machine's pneumatic, hydraulic and electrical systems installation of the switchgear cabinet design and realisation of the software final assembly test operation fine tuning and correction commissioning documentation It goes without saying that these phases are not necessarily dealt with consecutively. Generally, they overlap or parallel one another. Graphical methods are often used to illustrate the overlap or parallel nature of the individual phases and ensure the success of the project.

4 A-4 The Gantt chart Gantt charts use a two-dimensional coordinate system. The horizontal axis generally represents the time scale and the individual subtasks or actions are entered along the vertical axis. The length of the bars indicates the projected duration for the performance of the subtasks or action. The relative length and position of the bars to one another illustrates their temporal relationships. Overall, this technique is very simple and easy to learn. While it lends itself well to the illustration of 'AND' associations and chains, 'OR' associations or reactions cannot be represented using this technique. Fig. 1.2 Mechatronics Festo Didactic

5 A-5 As the development process of a machine or line becomes more complex, it becomes increasingly difficult to illustrate it using a Gantt chart. For this reason, network analysis is often used to plan complex projects. These networks consist of nodes and arrows. Depending on how these nodes and arrows are defined, we distinguish between action arrow networks event node networks action node networks The following will be concentrating on the action node network. In this type, the actions are represented as rectangles. Each of the rectangles contains exactly 8 items of information: Network analysis Action number Table 1.1 Description of action EST D EET LST BT LET EST - earliest start time LST - latest start time D - duration of action BT - buffer time EET - earliest end time LET - latest end time The arrows between the rectangles represent the relationships of the actions to one another. The actions are defined individually and placed in the appropriate logical sequence.

6 A-6 Fig. 1.3 Mechatronics Festo Didactic

7 A-7 The result is exactly one connection between the start and end points. The total duration of the project is the sum of the specified durations of the individual actions. This is known as the critical path, as delays along this path always result in delays for the project as a whole. A buffer time is not available along the critical path. The earliest and latest starting times are thus the same value. Certain buffer times result for the remaining connections depending on the specified times. This temporal view of the project sequence makes it easier for project participants to set priorities for their work. The following sections contain information on the various development phases as they apply to the training program for mechatronics specialists. Specifically, it includes: planning of complex automated lines installation of pneumatic systems installation of electrical systems vacuum technology sensor technology PLC technology analog signal processing technical communication commissioning We did, however, have to consider the overall volume of this binder while compiling the individual chapters. While the most important information can be found in the various sections, we could not go into detailed descriptions of individual issues. For this reason, please look upon Section B as reference material, rather than a mechatronics training manual.