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Aiming at the problems of low assembly knowledge shareability and reusability as well as long generation cycle of assembly process, this paper proposes an ontology-based assembly knowledge representation method, and generates assembly process file based on this method. The assembly ontology, modelling through protégé software, has three central classes: AssemblyObject, AssemblyElement, and AssemblyTool. The assembly ontology is described in OWL language and the assembly knowledge concepts including classes and individuals are linked through properties. In addition, the assembly ontology in OWL language is parsed through Python's RDFLib library, and it is called and displayed in LabVIEW. Finally, the assembly process file containing assembly sequence and assembly process parameters is generated. This method realizes the formal description of assembly process knowledge at the semantic level and improves the shareability and reusability of assembly knowledge. Besides, the corresponding assembly process knowledge can be quickly queried and obtained through this method, improving the efficiency of assembly process planning, and providing intelligent assembly basic knowledge.

The internal jaw stiffness of the silicon arm and its uniformity directly determine the geometric position of the clamped part, which in turn affects the geometric accuracy of the fusion target ball. The slight variation of the silicon arm jaw stiffness caused by machining errors is a crucial factor affecting the geometric accuracy of the micro-target. To accurately detect the variation of internal jaw stiffness caused by machining errors, this paper proposes a multi-point stiffness detection method combining micro-feed force application and high-precision image inspection. An experimental measurement device is also built to measure the jaw stiffness of the silicon arm sample. The proposed method, which can obtain the micro-deformation data of the internal jaws under small loads and accurately fit the stiffness, provides a new way to measure tiny, thin-walled, brittle cantilever beam structures.