An objective weighting method of function requirements for product design using information entropy

Weight of function requirements (FRs) plays an important role in product design. Based on weights of FRs, the priority structure and parameters of a product are decided to meet requirements of the product function, cost and lifecycle. The existing methods in defining weights of FRs mainly rely on users’ comments and experts’ experience, which is subjective. This paper proposes an objective method of weighting FRs for product design using information entropy and benchmarking methods. Initial weights of FRs are assigned by an analytic hierarchy process (AHP) method. The weights of FRs are then improved for objective solutions based on the similarity of benchmarking products using information entropy. Final weights of FRs are decided by the least square method. The proposed weighting method of FRs is verified in a case study of designing an upper limb rehabilitation device. Results show that the proposed method has improved weighting accuracy of FRs in product design. © 2020 CAD Solutions, LLC.