In Human-Computer Interaction, multi-material 3D printing is increasingly recognized for its capacity to produce conductive interactive objects. While various fabrication techniques have emerged in this domain, achieving the integration of highly conductive 3D structures within printed objects continues to pose a significant technical hurdle. Our study introduces Intercircuit, a novel integrated technique developed explicitly for fabricating highly conductive interactive objects. This method employs multi-material printing to form unified components along with their embedded structures of lower conductivity, enhancing conductivity through targeted plating. Distinct from traditional multi-material printing and surface conductivity augmentation methods, the Intercircuit method facilitates the creation of complex 3D circuitry while ensuring superior conductivity. Furthermore, this study introduces a supportive design tool aimed at aiding users in crafting conductive frameworks. Moreover, the practical application of this method is further elucidated through a series of case studies.

The advent of conductive thermoplastic flaments and multi-material 3D printing has made it feasible to create interactive 3D printed objects. Yet, challenges arise due to the volume constraints of desktop 3D printers and the high resistive characteristics of current conductive materials, making the fabrication of large-scale or highly conductive interactive objects can be daunting. We propose E-Joint, a novel fabrication pipeline for 3D printed objects utilizing mortise and tenon joint structures combined with a copper plating process. The segmented pieces and joint structures are customized in software along with integrated circuits. Then electroplate them for enhanced conductivity. We designed four distinct electrifed joint structures in the experiment and evaluated the practical feasibility and efectiveness of fabricating pipes. By constructing three applications with those structures, we verifed the usability of E-Joint in making large-scale interactive objects and showed the path to a more integrated future for manufacturing.

Touchable Pen is a writing instrument designed for the visually impaired. Raised Braille dots are printed when the nib touches any surface. It subverts traditional Braille writing, transforming subtractive manufacturing into additive manufacturing, and reverse writing into forward writing. The Touchable Pen uses low-cost technology to improve both the equity and efficiency of the writing experience for blind people.

Traditional pressure sensors are typically rigid and distinct from the product casing, limiting product design and form. This lack of flexibility makes creating comfortable and adaptable product casings challenging, stifling designers' creativity.

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Invisible is a parametric capacitive flexible pressure sensor crafted through a 3D printing process that combines conductive and non-conductive materials. This sensor seamlessly integrates into the parametric structure and overall product design, offering a perfect blend of customization and integration. This user-friendly approach caters to the convenience of designers and developers.

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With the innovative Invisible technology, we've designed two groundbreaking products:

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Gait Monitoring Pressure Detection Sports Shoes:These shoes go beyond conventional boundaries by visualizing gait pressure. Real-time pressure values from physical shoes sync with a virtual shoe model, generating dynamic pressure deformations. This unique fusion not only aids athletes in analyzing foot pressure but also empowers individuals with lower limb disabilities to gain insights into their foot pressure. The virtual shoe model also facilitates personalized shoe design based on individual foot shapes.

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Adaptive Body Posture Chair:Unlike traditional designs that compel individuals to adapt to the product shape, this chair revolutionizes sitting comfort. Poorly designed chairs often lead to incorrect postures and increased lumbar pressure over time. Our chair features real-time pressure detection, enabling precise control over the inflation and deflation of safety airbags. This adaptive technology allows the chair to respond dynamically to the user's posture, delivering enhanced lumbar support and protection over prolonged usage.

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Invisible technology, with its flexible and integrated approach, opens up new horizons in product design and functionality, a harmonious blend of comfort, adaptability, and innovation.

The AIRSAVER inflatable thermal insulation vest is designed for emergency rescue in cold environments. Lightweight and compact as a can, it is easily transportable. Pulling the lid triggers azide and catalyst to inflate the vest with nitrogen in seconds. The inner material insulates, while the outer material is windproof. AIRSAVER replaces bulky thermal clothing with an accessible solution for complex environments.