# Concept Justification of Future 3 DPVS and Novel Approach towards its Conceptual Development
## 3 Conceptual Design Approach for 3 DPVS
### Establishing Conceptual Design Process for 3 DPVS
#### 3.3.4 Concept Evaluation and Solution Validation
This is because in most cases when one single factor fails to function, then the whole functionality of scaffold could probably be ruined instantly. In this connection, after the subjective weighting criterion and obtaining a subjectively calculated score, further objective methods for evaluation are required. _Step 3: Determining the Weight, Significance and Priority of Each Criterion_  
The weights are determined by the relationship by the criteria and related requirements. The importance of each criterion should be in accordance with the prioritized requirement for 3 DPVS design. From the perspective of this study, vibratory functionality is considered as the chief or fundamental priority and this would potentially occupy half of the total weight of a concept. Another half can be for the normal effect on culturing cells, which could be similar to a traditional 3D passive scaffold working with external mechanism vibrations. Detailed weight will be accessible only when the weighting system is generated following specific methodology. _Step 4: Calculating the Score of Each Criterion and Ranking Concepts_  
This step will be a preparatory phase to estimate the scores of the alternative solution against each criterion and neglect inappropriate ones. As detailed information or value for each criterion in each cell culture application is difficult for designers to obtain in the conceptual design phase, each solution in the criteria is essentially judged by the knowledge, information and experience of cell cultivation and 3 DP fabrication from companies and academia, and compared subjectively. That is, a criterion will be objectively listed there as a constant \"yardstick\" for comparison, but how to compare will be relatively subjective. The results output of this will be used in the next step. _Step 5: Selecting the Principal (Optimal) Concept_  
When the overall scores or occupied significance of each solution are calculated, the one with the highest potential worth is selected as the optimal conceptual solution. The overall worth of an alternative solution is calculated according to the weights of the criteria and the score of the solution for each criterion. In this stage, the word 'best' is also a term of relativity, that is, the selected concept is best only in that given context from researchers' perceptual filters and reasoning. There is every possibility that the selected one is not suitable for practical use. So the following step, validating the concept via computer simulation, will help the design become more solid and reliable. This step involves validating concepts using computer simulation and 3 DP prototyping. While the optimal solution is relatively the best among the alternative solutions, it may still have defects that contradict the design requirements. For example, the optimal solution might have difficulty being transformed into CAD language, limiting 3 DP fabrication technologies to fulfil real prototyping of the designed 3 DPVS. Therefore, a further solid evaluation process is needed after step 3. In this process, the generated conceptual model of 3 DPVS, containing a combination of different parameters, will be evaluated through tools such as CAD first. Computer simulation might be used here to chiefly evaluate whether the required characteristics for the designed 3 DPVS in a given context, have been fully satisfied through the concepts generated in the previous stage. One evident advantage of using a CAD tool, such as Solidwork, to construct and simulate the model of 3 DPVS, is to efficiently test the function of each parameter, especially those for geometric control and mechanical properties. Otherwise the concepts merely selected through a philosophical criterion-weight system could be insufficient and impractical. CAD or simulation also helps judge whether the designed scaffold is technically feasible for 3 DP technologies. Regarding software, Solidworks or Comsol Multiphysics could be used.