Theoretical and Experimental Estimation of Uncertainty of Measurement during Calibration of CMM

  • Atul Dev Centre for Advance Mechanical Engineering Defence Electronics Applications Laboratory, Dehradun, India, GraphicEra (Deemed to be University), Dehradun, India
  • Smriti Tandon Graphic Era (Deemed to be University), Dehradun, India
  • Ved Parkash Centre for Advance Mechanical Engineering Defence Electronics Applications Laboratory, Dehradun, India
Keywords: CMM, Calibration, Uncertainty, ength Measurement, Probability Distribution


In the present paper we briefly discuss the universal (theoretical) and experimental methods of estimation of uncertainty of measurement. As an application we have taken the case of manual 3D co-ordinate measuring machine of with 1 µm least count and this machine has been calibrated with the help of a Step Gauge. The study concludes that both universal and experimental methods give fairly identical results and hence universal method can be used easily for the uncertainty calculation of such machines.This is first of its kind of work where theoretically estimated uncertainty value has been compared w.r.t. the practically observed value.


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