Integrating optimal experimental design into the design of a multi-axis load transducer

The determination of loads applied to a structure is often necessary in the design process. In some situations it is not feasible to insert a load cell in the system to measure these applied loads. In these cases, it would be expedient to utilize the structure itself as a load transducer. This can be accomplished by measuring strains at a number of locations on the structure. The precision with which the applied loads can be estimated from measured structural responses depends on the number of strain gages utilized and their placement on the structure. This paper presents a computational methodology which utilizes optimal experimental design techniques to select the number, locations and angular orientations of the strain gages which will provide the most precise load estimates based on the generalized load vector. Selection is made from a candidate set created using a finite element analysis. The application of this method is illustrated with an example.