ABSTRACT
Efficient and competitive manufacturing demands a systematic assembly planning procedure. The paper focuses on using and improving available processes for assembly planning that can be customised to suit the needs of small and medium-sized companies (SMEs).
Special attention should be given to the following:
Great flexibility and variability
Cost effectiveness
Change from parts manufacturer to component supplier
Consideration of an integrated planning process
Consideration of all preceding and subsequent processes and general conditions
Integration of planning and implementation of assembly systems into the business targets
Opening up the potential of virtual reality techniques.
The new planning algorithm for assembly integrates system planning for manual assembly. The reason for this expansion is that many companies have to rearrange their shop floor areas for assembly due to product changes or because they are establishing an assembly area for the first time. Moreover, in assembly planning, the assembly planner should follow a systematic paradigm.
132In addition to the integrated approach, new techniques should also support planning. Virtual Reality technology is an appropriate tool for efficient planning of both the system and the process. Virtual session members can see the assembled object itself as well as the components and their functionalities by means of Virtual Reality. Sectional views of the object can be shown and different components can be displayed transparently.
An important aspect of the virtual reality technique is the virtual model of a human being. This model makes it possible to check the accessibility of parts within the assembly system as well as the visible areas. Physical stress on the human worker and the worker’s posture can also be monitored within the assembly system.
As a result, it is not only possible to discover planning errors earlier, but also to avoid the expense of changes and follow-up costs.
To address these issues, planning-modules are developed for manual assembly. The planning-modules are part of the assembly planning procedure; they can be used repeatedly and are independent of the product.
The planning-modules include methods, tools and auxiliaries, such as the virtual representation of the product structure, graphs elucidating the sequence of assembly activities, known as precedence graphs and assembly plans. The planning engineers use the planning sequence in assembly in conjunction with their own know-how.
Data input into the planning-modules is information that is already available. Thus, the planning modules may be used and the planning results obtained may be documented. To be efficiently supported by Virtual Reality techniques, the planning modules and Virtual Reality techniques are used both in parallel and sequentially. For example, one may view the object in the virtual world in order to create the product structure.
Thus the virtual planning modules support the planning engineer and make it possible to avoid errors in the assembly object and the assembly system that do not exist in reality.
