Reconfigurable physical interfaces empower users to swiftly adapt to tailored design requirements or preferences. Shape-changing interfaces enable such reconfigurability, avoiding the cost of refabrication or part replacements. Nonetheless, reconfigurable interfaces are often bulky, expensive, or inaccessible. We propose a reversible shape-changing mechanism that enables reconfigurable 3D printed structures via translations and rotations of parts. We investigate fabrication techniques that enable reconfiguration using magnets and the thermoplasticity of heated polymer. Proposed interfaces achieve tunable haptic feedback and adjustment of different user affordances by reconfiguring input motions. The design space is demonstrated through applications in rehabilitation, embodied communication, accessibility, safety, and gaming.
doi.org/10.1145/3613904.3642802
Complex actuators in a small form factor are essential for dynamic interfaces. In this paper, we propose ConeAct, a cone-shaped actuator that can extend, contract, and bend in multiple directions to support rich expression in dynamic materials. A key benefit of our actuator is that it is self-contained and portable as the whole system. We designed our actuator’s structure to be multistable to hold its shape passively, while we control its transition between states using active materials, i.e., shape memory alloys. We present the design space by showcasing our actuator module as part of self-rolling robots, reconfigurable deployable structures, volumetric shape-changing objects and tactile displays. To assist users in designing such structures, we present an interactive editor including simulation to design such interactive capabilities.
doi.org/10.1145/3613904.3642949
We propose TensionFab, a novel technique for creating shape-changeable room-scale structures. This method employs easily available planar materials (plywood, MDF), cuts them into multiple 2D shapes, and then connects the pieces manually to create a unified structure capable of 2D and 3D deformations. Constructed TensionFab structures are characterized by easy achievability of target surfaces, substantial structural strength, shape changeability, time and material savings, and easy storage and transportation. In this paper, we introduce the basic principles of shape-making, module combination, and structural characteristics of TensionFab. We also developed a design assistance tool to allow users to automate design based on the target shape. We evaluate the design results for shape detection and structural performance. Finally, we validate the approach with actual construction and propose a variety of application scenarios. Overall, TensionFab is an efficient strategy for spatial design and structural organization. This paper contributes to research and exploration in the HCI room-scale interaction field.
doi.org/10.1145/3613904.3641958
We propose augmenting initially passive structures built from simple repeated cells, with novel active units to enable dynamic, shape-changing, and robotic applications. Inspired by metamaterials that can employ mechanisms, we build a framework that allows users to configure cells of this passive structure to allow it to perform complex tasks. A key benefit is that our structures can be repeatedly (re)configured by users inserting our configuration units to turn the passive material into, e.g., locomotion robots, integrated motion platforms, or interactive interfaces, as we demonstrate in this paper. To this end, we present a mechanical system consisting of a flexible, passive, shearing lattice structure, as well as rigid and active unit cells to be inserted into the lattice for configuration. The active unit is a closed-loop pneumatically controlled shearing cell to dynamically actuate the macroscopic movement of the structure. The passive rigid cells redirect the forces to create complex motion with a reduced number of active cells. Since the placement of the rigid and active units is challenging, we offer a computational design tool. The tool optimizes the cell placement to match the macroscopic, user-defined target motions and generates the control code for the active cells.
doi.org/10.1145/3613904.3642891
Understanding how professionals use digital fabrication in production workflows is critical for future research in digital fabrication technologies. We interviewed thirteen professionals who use digital fabrication for the low-volume manufacturing of commercial products. From these interviews, we describe the workflows used for nine products created with a variety of materials and manufacturing methods. We show how digital fabrication professionals use software development to support physical production, how they rely on multiple partial representations in development, how they develop manufacturing processes, and how machine control is its own design space. We build from these findings to argue that future digital fabrication systems should support the exploration of material and machine behavior alongside geometry, that simulation is insufficient for understanding the design space, and that material constraints and resource management are meaningful design dimensions to support. By observing how professionals learn, we suggest ways digital fabrication systems can scaffold the mastery of new fabrication techniques.