Towards Mass Production of Smart Products by Forming Technologies

Abstract

In all areas of technology, the demand for high-quality, competitive and more valuable products is rising steadily. One approach to increase the value of manufactured products is the integration of electronic components in load carrying structures. These new products, which combine electrical and mechanical components synergistically, are called smart products. They consist of a passive structure and integrated electronics or smart materials. In addition to their mechanical properties they are also able to sense, to actuate or to transmit energy or data. The resulting product architecture requires both a mechanical and an electronic design in order to save subsequent assembly costs. Since further components are required to evaluate and control as well as to supply energy, all of those components need to be connected and integrated into the smart product. However, the main prerequisite for the marketability is the possibility of low-cost manufacturing and a robust mass production. Nowadays processes for the manufacturing of smart products do not fulfill the requirements for a sustainable mass production in a satisfying way as long as metallic structures are used. The authors deploy the forming technologies roll forming and sheet metal hydroforming to form sheets with applied flat electronics. Since the components are applied prior to the forming process, small and difficult to access installation spaces can be used effectively in the product architecture. The incremental bulk forming process rotary swaging is employed to integrate piezoceramics during the forming procedure without any additional joining elements. Challenges resulting from the chosen integrative manufacturing approach are the prevention of new kinds of failure modes and additional requirements for defined residual stress states. These challenges lead to extended process design requirements, which will be discussed in the paper in detail.

Integration of Piezoceramic Tube under Prestress into a Load Carrying Structure

“…After the start of calibration phase, the residual force in between two tool strokes is about 450 N. This prestress is expected to provide a friction lock of the piezoceramic within the metallic structure. To achieve defined prestress, different parameters are proposed in [9], including temperature and an axial preload of the tube during the forming procedure. Fig.…”

“…Bulk structures. Large-scale production of bulk structures with actuatory and sensory abilities is presented by means of a rotary swaging process [9]. The fusion of carrying structure and smart materials is realized by a joining operation which takes place simultaneously with the manufacturing process [10].…”

Impact Localization for Haptic Input Devices Using Hybrid Laminates with Sensoric Function

“…There are different approaches for integrating functions directly into the semi-finished product and these can be differentiated according to the type of semi-finished product. On the one hand, functions can be integrated into sheet metal structures by printing strain gauges onto a tube as described by Ibis and Groche [2] or by joining a piezoceramic ring into a metal tube using forming technology as reported by Brenneis et al [3]. On the other hand, sensor integration can be realized through direct integration of macro-fibre composites (MFCs) into a sheet metal structure as shown by Müller et al [4].…”