Abstract
New production technologies like 3D printing and other adaptive manufacturing technologies have changed the industrial manufacturing process, often referred to as next industrial revolution or short industry 4.0. Such Cyber Physical Production Systems combine virtual and real world through digitization, model building process simulation and optimization. It is commonly understood that measurement technologies are the key to combine the real and virtual worlds (eg. [Schmitt 2014]). <br><br> This change from measurement as a quality control tool to a fully integrated step in the production process has also changed the requirements for 3D metrology solutions. Key words like MAA (Measurement Assisted Assembly) illustrate that new position of metrology in the industrial production process. <br><br> At the same time it is obvious that these processes not only require more measurements but also systems to deliver the required information in high density in a short time. Here optical solutions including photogrammetry for 3D measurements have big advantages over traditional mechanical CMM’s. <br><br> The paper describes the relevance of different photogrammetric solutions including state of the art, industry requirements and application examples.
Highlights
While in photogrammetry usually a simple standard deviation is stated as system accuracy, most industry standards ask for maximum permissible errors (MPE)
The maximum permissible length measurement error is the criterion for the quality of the measuring system. This is a much stricter description of accuracy and had led to some confusion in the market as some companies continued to promote accuracies based on simple standard deviations, but the consequent testing of systems according to VDI/VDE 2634 has led to a much higher acceptance of photogrammetry in the industrial market
The same procedure is used to align patches from white light scanning devices on large reference grids created by photogrammetry
Summary
Newer generations of digital cameras with larger sensors fostered the ability to deliver 3D measurement results on multiple points immediately after the measurement was taken, nowadays sometimes even in real-time These features, together with highest accuracy and high flexibility and mobility of camera based measurement systems creates the core advantages of industrial photogrammetry up to now. At the same time portable CMM devices like articulated arms or laser trackers have been developed to address the need of fast onsite response to a measurement problem As these devices are usually based on single point probing, they work more similar to traditional CMM’s and have been easier adopted by the industry and outnumber photogrammetric solutions by far.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have