Towards Realizing Cybermanufacturing Kiosks: Quality Assurance Challenges and Opportunities

This paper presents the cyberphysical system (CPS) challenges associated with realizing manufacturing-as-a-service paradigm, capable of creating custom functional, freeform structures. While earlier efforts have addressed the product design, resource allocation, and asset management challenges in custom manufacturing, those pertaining to quality and performance assurance have not received much attention thus far. For low volume custom manufacturing, the intelligence comprising all the steps involved in the production process and its continuous monitoring should reside in the real-time service, rather than requiring an upfront costly design process for each product. In this paper, we first outline the technical challenges associated with autonomous monitoring and control of tool motion and process parameters of a laser kirigami (origami with cuts) process to create custom freeform components, with planar facets, from peel-off sensors embedded on sheet precursors. In the sequel, we present an implementation of image-based monitoring, particularly for the estimation of the dihedral angle between the facets being bent during the laser kirigami process. As the sheet is formed, the sensors embedded on the sheets serve as a swarm of mobile sensors whose instantaneous location and orientation are discerned using optimally placed cameras to estimate the process state. This allows the tuning of process parameters, specifically the laser intensity and transverse feed rate to mitigate quality issues. The results from the current experimental investigations of the laser kirigami process suggest that the process state can be estimated to error rates of less than 2% at 10 frames per second, which is orders of magnitude faster than that achievable using the present stereo digital image correlation technologies.