Мехатроника 1 Бөлім mechatronics
Development of technical requirements
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Мехатроника 1 том Баймухамедов М.Ф., Джаманбалин Қ.Қ.,Ақгул м.К.
| 4.5.3 Development of technical requirements
In the design tasks, the path from the analysis of the relationships to the clearly formulated technical requirements for the mechatronic module required by the designer may be more complicated than the one considered above. This path can take place through such stages of creating a mechatronic module, such as research and development, modeling, intermediate prototyping, and can also be accompanied by computational and experimental work not always performed with the participation of the designer. In the list of technical requirements, not the communications themselves are given, but the technical characteristics of the mechatronic module and parameters that reflect the conditions of its operation [11]. 217 Technical requirements can be divided into four groups. The first group. Requirements that contain geometric and constructive cons- traints . Example of wording: the maximum deviation of the axle distance is ±0.5 mm. The second group. Requirements expressed through technical or physical concepts, written in the form of numbers with dimensions. Example of wording: the resistance force at the output link is not more than 100 N. The third group. Requirements expressed verbally, which do not include either concepts defined quantitatively, or geometric constraints in the design. Example of wording: the device must be quick-detachable. The fourth group. Requirements formulated with complex concepts or ma- thematical dependencies. The first group of requirements is significantly replenished as a result of the discovery of restrictions related to the location of the designed mechatronic module. The second group of requirements is largely the result of a quantitative mapping of the interrelationships of the mechatronic module with the external environment and the features of the schematic diagram.The constructive reali- zation of the requirements, expressed with the help of clear technical concepts defined quantitatively (such as, for example, as a gear ratio), can be implemented in various ways. The advantages of this form of writing requirements are very large, as it does not carry uncertainty and serves as a means of an objective verification of the correctness of the design. All that has been said about the second group of requirements can be attributed to the fourth group. We should especially mention the third group of requirements. The verbal form of writing technical requirements in most cases indicates the incomple- teness of the process of formalizing the real physical picture. Sometimes it is generated by the lack of information about the quantitative side of certain relationships or the lack of knowledge of the essence of any processes in the mechatronic module-environment mechatronic system. Often the verbal formu- lation by means of very general concepts unites a set of undisclosed relations. An example of this formulation: «The mechatronic module should be easy to use, when installing and dismantling.» The designer, specifying and supplementing the terms of reference for himself, should decipher this point by considering the most significant inter- relations between the mechatronic module and the servicing personnel. But this does not mean that one should strive for the most complete formalization of all technical requirements without exception. The degree of necessary formalization is determined, on the one hand, by the difficulties of its imple- mentation, on the other hand by the requirements of the subsequent stages of construction. 218 The process of implementing requirements in the design is accompanied by back interactions for technical requirements. To implement a rational per- centage of «requirements implementation,» the designer should be able to vary within the permissible limits the parameters of the technical requirements. It is therefore important in the requirements to reflect not only the nominal, but also the limiting values of the values to be pledged. Requirements for the mechatronic module can not be formulated if the general direction of the design is not chosen. The question of what to do is inseparable when designing from the question of how to do it. The completed list of technical requirements always reflects the degree of clarity of the designer’s views on the chosen direction of work. жүктеу/скачать 11,25 Mb. Достарыңызбен бөлісу:
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