Overcoming Conflicts of Objectives Between Sensory and Mechanical Domain in the Development of Sensor-Integrating Machine Elements Using the Example of Bolts

Comprehensive data on machines is essential for digitization in the industry. Since standardized machine elements are used in most machines, integrating them with sensors provides the opportunity to acquire data comprehensively from in-situ. The sensor integration must not change the element’s core function and the standardized mechanical interfaces. Hence, sensors must be fully integrated and self-sufficient. Regarding bolts as widely used machine element, a solution that combines all the aforementioned requirements does not yet exist. A main problem in developing sensor-integrating machine elements and especially bolts is to overcome the conflicting objectives in defining design space for mechanical and sensory functions. There is a lack of an approach to model the effects of the design space parameters on the mechanical and sensory functions. This paper proposes an optimization function to aid mechanical and electrical engineers in resolving conflicting objectives by balancing function fulfillment when determining design space parameters. Therefore, the effects of the parameters on the mechanical and sensory functions are modelled using FE-analysis and composing an optimization function with weights. This function provides optimal design space parameters. With respect to mountability boundary conditions the optimum for equal weights is at diameters 13.2mm both, increasing v. Mises stress by 29% and strain at sensor position by 80%. The location of the optimum is very dependent on proper weighting, which resembles a prioritization of the mechanical versus the sensory function fulfillment. This enables engineers to find optimal parameters by balancing the mechanical and the sensory function fulfillment.