Comparison Between Laser Radar and Photogrammetry
July 14, 2010 at 8:30 am
Carson Rooms 3 and 4, enter at Carson 3
Randy Fratena - Representing Harris Corp.
Purpose
At the Harris Corporation (Government Communications Systems Division – GCSD) solid dish carbon fiber reflectors are manufactured to support military ground, sea, & air communications. To meet performance requirements, the surface profile of these reflector dishes are held to rigid tolerances. For 25 years, Photogrammetry has been the standard to characterize the surface profile of these reflectors. This technique has been “Tried and True” and is familiar with both the engineering and the quality organization.
The photogrammetric process is labor intensive, demands highly trained operators, and requires supplemental materials (i.e. codes, target, scale bars). A Laser Radar was evaluated as an alternate measurement technique to minimize labor hours, eliminate supplemental materials, and automate the measurement process to reduce the dependence of experienced operators.
Hypothesis
The percent difference of the surface profile value (Root Mean Square, RMS) between Photogrammetry and Laser Radar is ≤ 10%.
Tools
The Laser Radar system is an independent stand-alone measurement tool designed for rapid data collection on a Spatial Analyzer (SA) software platform. The accuracy stated by the manufacturer is +/- .0006” per meter. Additionally, the Spatial Analyzer software requires no third party software to process measurement data.
The photogrammetric camera is used for small and large scale Metrology measurement. The camera’s accuracy stated by the manufacturer is +/- 0.002” per 4 meters. The camera is supported in conjunction with codes, various style targets, and scale bars. Third party software (i.e. MATLAB) is required for processing of the measurement data.
Data Collected
On a variety of reflector shapes and sizes (1.3, 2.5, 4.9 Meter), the RMS value will be calculated with the Laser Radar and Photogrammetry. The percent difference between the RMS values will be reported. Additionally, the cost savings (i.e. reduction of labor hours) will also be captured.
Summary
The data captured in this study realized the < 10% difference between RMS values generated by Photogrammetry and Laser Radar. On various sized reflectors, the percent difference ranged between 2% to 6%. Also, the reduction in labor hours was ~ 70%.
Carson Rooms 3 and 4, enter at Carson 3
Randy Fratena - Representing Harris Corp.
Purpose
At the Harris Corporation (Government Communications Systems Division – GCSD) solid dish carbon fiber reflectors are manufactured to support military ground, sea, & air communications. To meet performance requirements, the surface profile of these reflector dishes are held to rigid tolerances. For 25 years, Photogrammetry has been the standard to characterize the surface profile of these reflectors. This technique has been “Tried and True” and is familiar with both the engineering and the quality organization.
The photogrammetric process is labor intensive, demands highly trained operators, and requires supplemental materials (i.e. codes, target, scale bars). A Laser Radar was evaluated as an alternate measurement technique to minimize labor hours, eliminate supplemental materials, and automate the measurement process to reduce the dependence of experienced operators.
Hypothesis
The percent difference of the surface profile value (Root Mean Square, RMS) between Photogrammetry and Laser Radar is ≤ 10%.
Tools
The Laser Radar system is an independent stand-alone measurement tool designed for rapid data collection on a Spatial Analyzer (SA) software platform. The accuracy stated by the manufacturer is +/- .0006” per meter. Additionally, the Spatial Analyzer software requires no third party software to process measurement data.
The photogrammetric camera is used for small and large scale Metrology measurement. The camera’s accuracy stated by the manufacturer is +/- 0.002” per 4 meters. The camera is supported in conjunction with codes, various style targets, and scale bars. Third party software (i.e. MATLAB) is required for processing of the measurement data.
Data Collected
On a variety of reflector shapes and sizes (1.3, 2.5, 4.9 Meter), the RMS value will be calculated with the Laser Radar and Photogrammetry. The percent difference between the RMS values will be reported. Additionally, the cost savings (i.e. reduction of labor hours) will also be captured.
Summary
The data captured in this study realized the < 10% difference between RMS values generated by Photogrammetry and Laser Radar. On various sized reflectors, the percent difference ranged between 2% to 6%. Also, the reduction in labor hours was ~ 70%.
