# Research on Design Method of Product Functional Hybridization for Integrated Innovation
## 2 Related Research
### Functional Integration  
Functional integration is the method of integrating multiple functions to form a new multi-functional product. It can improve the overall performance of the product function system to adapt to changes in the market and environment. Based on analyzing the evolutionary process of product function systems, [PERSON] et al. [31] proposed a function combination pattern of existing products for integrated innovation. In this pattern, potential customer needs were obtained by analyzing products that had similar, opposite, or different functions from the prototype product. However, it did not provide a specific process for searching products. [PERSON] [32] constructed a multi-domain knowledge-acquisition method based on the function-oriented search to achieve function fusion. The scope of function acquisition mainly covers patent databases. [PERSON] et al. [33] proposed a function-based product integration approach. A function-sharing matrix and a component-sharing matrix were created based on the reconfigurable principle to identify the shared functions and components of two products. After that, a new product was obtained by combining the functional structure of the integrated product. The approach focused on assessing the feasibility of integrating two existing single-state products to produce a new reconfigurableor multifunctional product, and it did not describe how to obtain the integrated product. [PERSON] et al. [34] presented the establishment of a functional combination matrix to innovatively form various products and enrich the product system through the combination and collocation of functions. However, in this method, functions were known, and there was no process to acquire new functions. [PERSON] et al. [35] proposed a design process for function combination. In this process, the product function was decomposed to analyze the combination relationship between the sub-functions, and the function combination solution was selected according to the market demand. This process mainly focused on the recombination of the product's own functional resources. [PERSON] et al. [36] proposed a function combination method for conceptual design based on the functional structure and design matrix to combine multiple product functions into a single product. The method mainly analyzed the functional redundancy in the process of functional combination. [PERSON] et al. [37] and [PERSON] [38] proposed functional recombination methods for the integration of multi-biological effects and biological features, which were mainly aimed at solving and improving functions. [PERSON] et al. [39] described four generic strategies of functional integration derived gradually from differential designs. This study used different strategies to generate solutions in a systematic way. Moreover, these strategies were proposed to save weight, cost, and time for assembly and gain more installation space. To reduce the complexity of the design task, [PERSON] et al. [40] presented an approach for multi-functional design. The method aimed to achieve different functions in a single structure that could be applied to the process of developing multi-functional components. Product functional hybridization is the utilization of existing resources. Obtaining the required goal products and achieving the fusion of existing product function systems are two keys to facilitating product functional hybridization. In the above literature, there are fewer studies on how to obtain the goal products. They mainly gained the goal products by means of functional search under the premise of obtaining the user's functional requirements. However, the scope of acquisition is wide, and the number of goal products generated is high. Thus, a problem that the goal products are not highly applicable and not strongly related to the prototype products arises. Product functional hybridization requires the creative fusion of design elements to achieve complementary advantages.