A general approach of engineering design

There are, on the scientific market, many concepts that examine the main topics related to the engineering design activity. Among them: Total Design concept, Concurrent Engineering concept, Simultaneous Engineering concept, KANSEI Engineering concept and so on. In this paper the authors will examined the engineering design activity related to all aspects that take place for entire duration of Product Life Cycle (PLC). A new diagram is introduced in order to define Product Green Life Cycle (PGLC). The system or product that has to be designed will be split in two subsystems: one is related to the product functions and its components and the second one is related to the aspects of product manufacturing. There will be examined the transformations which are applied on the inputs in order to obtain the needed outputs. Due to the needed inputs and transformations, will result not only needed outputs, but many other secondary outputs. Part of the secondary outputs will claim other secondary inputs. All have to be pounted out with accuracy. The block diagrams will be the main instrument used in the proposed approach, for both subsystems. The presented methodoloty can be applied to any activity for the entire PGLC. A logical flow chart that can be used at any design stage is presented, also. A case study, for a kinematics axis, is showed in order to clarify and emphasize the theoretical approach.