Strain gauge technology

Publisher SummaryThis chapter discusses the strain gauge technology. Strain gauge measurement is a technique that is based upon the connection between the deformation of an object of measurement and the changes in the electrical resistance of a conductor which is attached to it. Strain gauges are equally useful for the measurement of positive as well as negative changes in length (tensions as well as compressions). An ever increasing requirement for stronger and lighter constructions for use in the aviation industry made it necessary to be able to document the load conditions. Furthermore, using the strain gauge measurements, it was possible to improve the theoretical models for complicated objects. Strain gauges are used in the industry as transducers for weight and pressure measurements. In addition to this industrial production of transducers based upon the principle in strain gauge measurements, the technology is a unique tool for the evaluation of strengths of materials, for example, in connection with the analysis of failures, load conditions, residual lifetimes, vibrations, etc. Strain gauge measurements only provide information about the stresses at those points where the strain gauges have been placed. It is, therefore, of critical importance that the positions are selected by individuals with insight regarding the strength of materials.