Large Volume Metrology Assisted Production of Aero-structures

Student thesis: Doctoral ThesisPhD


The research presented in this thesis was carried out within the Large Volume Metrology group at the University of Bath.The main goal of the research study is to develop and demonstrate novel applications of integrated and automated metrology systems in aerostructure production, with a particular focus on the development and capability assessment of real-time metrology integration.A survey through the relatively limited amount of literature on the state ofthe art of integrated and automated metrology showed some promisingresults.Encouraged by the positive results, studies were undertaken showing thatmany of the current aero-structure production issues involving measurementand data processing can be solved through better integration andautomation of metrology systems. It was partially demonstrated that thehealth assessment of an entire wing jig could be carried out automaticallywithin 13 minutes, compared to the traditional manual process which couldtakes many days.To better understand and quantify the capabilities and benefits of ahypothetical production system with integrated metrology, methods ofmathematically simulating Metrology Assisted Assembly (MAA) systems weredeveloped, and tested in a number of application case studies. It was shownthat MAA processes can be effectively simulated using the Monte Carlomethod. The case studies showed that these simulations can provide criticalinsight and information of the processes to the decision makers.The practical implementations of real-time integration with metrologyinstruments, a key enabler of MAA, were then addressed, and softwaremethods of interfacing directly with a number of instruments in real-timewere developed and demonstrated. The potential application of real-timemetrology in mobile robot navigation was also highlighted.Finally, building upon software instrument interfaces, a prototype 3-axismachine was constructed using low cost off-the-shelf components in orderto demonstrate the potentials of real-time MAA for manufacturing processessuch as milling and drilling. Using a laser tracker to provide real-time errorcorrection, it was possible to dramatically increase the positioning accuracyand repeatability of the machine. Using real-time feedback, a 50%reduction in static repeatability and 40 to 140 times reduction in staticpositioning errors were achieved.
Date of Award31 Dec 2013
Original languageEnglish
Awarding Institution
  • University of Bath
SupervisorPaul Maropoulos (Supervisor), Antony Mileham (Supervisor), Jafar Jamshidi (Supervisor) & Patrick Keogh (Supervisor)


  • metrology intergration
  • laser tracker
  • iGPS
  • machine tool
  • assembly simmulation

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