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Machining accuracy is the most critical indicator to evaluate the machining quality of parts in metal cutting industry. However, it is difficult to be identified before real cutting, because of a variety of error sources presented in a machining process system, such as assembly inaccuracy of machine tool, deformation caused by temperature variation and dynamic cutting force, tool wear, servo lag and so on. Consequently, it is difficult to determine whether a new machining process can satisfy accuracy requirements beforehand. Traditionally, a machining process is validated through the “trial and error” approach, which is time consuming and costly. If machining accuracy can be predicted to a large extent, a rational process can be planned to ensure the precision of parts and even to maximize resource utilization without trial cuts. For this purpose, this work focuses on machining accuracy prediction for five-axis peripheral milling based on the geometric errors. An error synthesis modeling method is proposed to integrate the geometric errors of the process system, including machine tool geometric error, workpiece locating error, cutting tool dimension error and setup error. From a multi-body system point of view, all these errors are synthesized to generate position error of the cutting contact point in the workpiece coordinate system. Then the machining error is obtained by projecting the position error to the workpiece normal vector, which can be measured by a coordinate measuring machine. The prediction model has been evaluated by a cutting test with our in-house-developed prototype software. The result shows that the proposed method is feasible and effective.

Conceptual design has a decisive impact on the product development time, cost and success. This paper presents a new conceptual design method for achieving rapid and effective mapping from product design specification (PDS) to concept design. This method can guide the creation of reasonable mapping among the PDS, behaviour parameters and structure parameters and to evaluate the rationality of performance parameters and structure parameters to confirm a reasonable conceptual design scheme. In this method, we establish a PDS-behaviour-structure conceptual design model to support the conceptual design of multi-disciplinaryoriented complex product system (CoPS) and develop a vector-based mapping tool in this method to support the rapid mapping, and demonstrate its feasibility and effectiveness by a case study. This method is not only supportive to realise the automation of a conceptual design process but also helpful to evaluate the conceptual design in the field of engineering design.

： The customer requirement modeling is a highly important part of a product development process for understanding the customers and market needs. But with the increasing of complexity of complex mechatronic products, it is necessary to involve multidisciplinary design teams, thus, the traditional customer requirements modeling for a single discipline team becomes difficult to be applied in a multidisciplinary team and project since team members with various disciplinary backgrounds may have different interpretations of the customers' requirements. This paper provides a new synthesized multidisciplinary customer requirements modeling method for obtaining and describing the common understanding of customer requirements and more importantly transferring them into a detailed and accurate product design specifications (PDS) to interact with different team members effectively. A case study of designing a high speed train verifies the rationality and feasibility of the proposed multidisciplinary requirement modeling method for complex mechatronic product development.Key words: complex mechatronic product, multidisciplinary customer requirements modeling, disciplinary specialty language dictionary, high-speed train 1.IntroductionWith the mass customization of product design and development, the individuality and diversity of customer requirements for a complex mechatronic product is ever increasing, the manufacturer enterprises are facing tremendous pressures and challenges to deal with the diverse and rapid changing customer and market requirements. The traditional "product-centric" design method for complex mechatronic products has been unable to adapt to the growing market competition, therefore, the enterprises should shift the design focus to the "customer-centric" design methods for complex mechatronic products. Customer requirement modeling thus becomes a highly significant part of a product development process and it also has been a research topic for years and used in the field of system and software development [1].The ultimate purpose of traditional customer requirements modeling is that realizes the mapping of CRs in the customer domain to PDS (a formalized specification of customers' requirements and a list of the product performance, environment, quality, reliability, security, life cycle and other elements with considering performance and cost constraints, design inputs, constraints and goals and so on [30]) in the designer domain to improve the development efficiency and reduce the development cost. Through many years of research and application, the process of traditional customer requirements modeling, encompassing requirement elicitation, requirement analysis and requirement verification, has been formed into a standardization process from a system and software engineering point of view [2]. The requirement elicitation is to extract Biographical notesMA Xiaojie, born in 1986, is currently a PhD candidate at Institute of Advanced Design and Manufacturing,

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