Abstract

Recent increase in development of complex electro-mechanical systems has resulted in an increased usage of electric cables harnessed and confined in enclosed spaces and often operating at high temperatures and/or within powerful electromagnetic fields. Generating digital twins of electric cables and wire harness systems is a multidisciplinary task consisting in designing both the electrical system circuit and the mechanical three-dimensional layout. The mechanical design of the three-dimensional layout is challenging because the non-linear behavior of many electric cables and wire harnesses enclosed within confined spaces must be considered for validating the results. This study deals with determining the non-linear mechanical properties of wire harnesses that are enclosed in tubular sleeves and/or reinforced with tapes. Such properties are essential data necessary for validating and optimizing the digital twins of the electric cables and wire harness assemblies. These mechanical properties are determined by data fitting wire harness CAE models against test data of multiple wire harnesses with given numbers of wires and enclosed in various sleeves and/or tapes. The dependency of the wire harness mechanical properties on parameters such as the number of wires, harness diameter and sleeve and/or tape type is observed and analyzed. The results show that both linear and non-linear mechanical properties of the wire harnesses depend on these parameters. The dependency functions of the wire harnesses mechanical properties on the number of wires is particularly important since this number can change significantly within a wire harness assembly. Fortunately, these functions exhibit smooth dependency on the wire harness diameter, and indirectly on the number of wires. Therefore, interpolation can be used successfully to determine from a limited set of test data the mechanical properties of harnesses with varying number of wires. Such interpolated parameters were later used to determine shapes and reaction forces on a wire harness design assembly. The results have shown significant harness shapes and reaction force differences when compared against a model that does not consider the permanent deformations in wires.