A study of fiducial aided precision positioning of ultra-precision freeform surfaces

M. Ren, Chi Fai Cheung, L. Kong

Research output: Chapter in book / Conference proceedingConference article published in proceeding or bookAcademic researchpeer-review


The fabrication of ultra-precision freeform surfaces possessing non-rotationally symmetric geometry and sub-micrometre form accuracy requires an efficient positioning method for precisely locating the position of the workpiece on the machine with high repeatability during the manufacturing cycle. This paper presents an initial attempt to develop a fiducial aided positioning (FAP) method for precisely locating the freeform workpiece on multi-axis machine tools in order to improve the accuracy and efficiency in the manufacturing of ultra-precision freeform surfaces. The FAP method makes use of fiducials to establish intrinsic surface features of the freeform workpiece which are used to determine the coordinate transformation between the coordinate frame of the workpiece and the machine in the machining process and the measurement process. A preliminary simulation experiment was conducted to verify the technical feasibility of the proposed FAP method. The results show that the FAP method is technically feasible to establish a link between the machining and measurement process so as to improve machining accuracy.
Original languageEnglish
Title of host publicationKey engineering materials
Number of pages5
Publication statusPublished - 2016


  • Freeform surfaces
  • Measurement
  • Precision positioning
  • Ultra-precision machining

ASJC Scopus subject areas

  • Mechanical Engineering
  • Mechanics of Materials
  • Materials Science(all)

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