This paper presents a design space, a fabrication system and applications of creating fluidic chambers and channels at millimeter scale for tangible actuated interfaces. The ability to design and fabricate millifluidic chambers allows one to create high frequency actuation, sequential control of flows and high resolution design on thin film materials. We propose a four dimensional design space of creating these fluidic chambers, a novel heat sealing system that enables easy and precise millifluidics fabrication, and application demonstrations of the fabricated materials for haptics, ambient devices and robotics. As shape-change materials are increasingly integrated in designing novel interfaces, milliMorph enriches the library of fluid-driven shape-change materials, and demonstrates new design opportunities that is unique at millimeter scale for product and interaction design.

Currently, the manufacturing of self-actuating and self-sensing robots requires non-standard manufacturing techniques and assembly steps to integrate electrical and mechanical systems. In this work, we developed a novel manufacturing technique, where such robots can be produced at a flexible electronics factory. We developed the technique using standard industrial machines, processes, and materials. Using a lamination process, we were able to integrate air pouches or shape memory alloy (SMA) inside a polyamide-based flexible circuit to produce bending actuators. The bend angle of the actuators is sensed with a chain of inertial measurement units integrated on the actuator. Air-pouch actuators can produce a force of a 2.24N, and a maximum bend angle of 74 degrees. To demonstrate, we manufactured a five-legged robot with the developed actuators and bend sensors, with all the supporting electronics (e.g., microcontrollers, radio) directly integrated into the flexible printed circuit. Such robots are flat and lightweight (15 grams) and thus conveniently compact for transportation and storage. We believe that our technique can allow inexpensive and fast prototyping and deployment of self-actuating and self-sensing robots.

Printflatables is a design and fabrication system for human-scale, functional and dynamic inflatable objects. We use inextensible thermoplastic fabric as the raw material with the key principle of introducing folds and thermal sealing. Upon inflation, the sealed object takes the expected three dimensional shape. The workflow begins with the user specifying an intended 3D model which is decomposed to two dimensional fabrication geometry. This forms the input for a numerically controlled thermal contact iron that seals layers of thermoplastic fabric. In this paper, we discuss the system design in detail, the pneumatic primitives that this technique enables and merits of being able to make large, functional and dynamic pneumatic artifacts. We demonstrate the design output through multiple objects which could motivate fabrication of inflatable media and pressure-based interfaces.

This work presents a method for 3D printing hair-like structures on both flat and curved surfaces. It allows a user to design and fabricate hair geometries that are smaller than 100 micron. We built a software platform to let users quickly define the hair angle, thickness, density, and height. The ability to fabricate customized hair-like structures not only expands the library of 3D-printable shapes, but also enables us to design passive actuators and swipe sensors. We also present several applications that show how the 3D-printed hair can be used for designing everyday interactive objects.

To meet the increasing requirements of HCI researchers who are looking into using liquid-based materials (e.g., hydrogels) to create novel interfaces, we present a design strategy for HCI researchers to build and customize a liquid-based smart material printing platform with off-the-shelf or easy-to-machine parts. For the hardware, we suggest a magnetic assembly-based modular design. These modularized parts can be easily and precisely reconfigured with off-the-shelf or easy-to-machine parts that can meet different processing requirements such as mechanical mixing, chemical reaction, light activation, and solution vaporization. In addition, xPrint supports an open-source, highly customizable software design and simulation platform, which is applicable for simulating and facilitating smart material constructions. Furthermore, compared to inkjet or pneumatic syringe-based printing systems, xPrint has a large range of printable materials from synthesized polymers to natural micro-organism-living cells with a printing resolution from 10μm up to 5mm (droplet size). In this paper, we will introduce the system design in detail and three use cases to demonstrate the material variability and the customizability for users with different demands (e.g., designers, scientific researchers, or artists).

This studio introduces methods of making and controlling inflatable fabric. We provide materials and simple fabrication processes that enable designers to rapidly prototype inflatables with simple hinging transformations or texture change. Furthermore, we introduce a customized hardware that enables designers to rapidly prototype inflatable fabric. The goal of this studio is to provide hands-on experiences of designing inflatable fabric as shape-changing materials and research on shape-changing artifacts. Basic knowledge of programming in Arduino is required. Participants should bring their own laptop for the studio.

This paper presents a design, simulation, and fabrication pipeline for making transforming inflatables with various materials. We introduce a bending mechanism that creates multiple, programmable shape-changing behaviors with inextensible materials, including paper, plastics and fabrics. We developed a software tool that generates these bending mechanism for a given geometry, simulates its transformation, and exports the compound geometry as digital fabrication files. We show a range of fabrication methods, from manual sealing, to heat pressing with custom stencils and a custom heat-sealing head that can be mounted on usual 3-axis CNC machines to precisely fabricate the designed transforming material. Finally, we present three applications to show how this technology could be used for designing interactive wearables, toys, and furniture.

Nature has engineered its own actuators, as well as the efficient material composition, geometry and structure to utilize its actuators and achieve functional transformation. Based on the natural phenomenon of cells' hygromorphic transformation, we introduce the living Bacillus Subtilis natto cell as a humidity sensitive nanoactuator. In this paper, we unfold the process of exploring and comparing cell types that are proper for HCI use, the development of the composite biofilm, the development of the responsive structures, the control setup for actuating biofilms, and a simulation and fabrication platform. Finally, we provide a variety of application designs, with and without computer control to demonstrate the potential of our bio actuators. Through this paper, we intend to enable the use of natto cells and our platform technologies for HCI researchers, designers and bio-hackers. More generally, we try to encourage the research and use of biological responsive materials and interdisciplinary research in HCI.

This works introduces layer jamming as an enabling technology for designing deformable, stiffness-tunable, thin sheet interfaces. Interfaces that exhibit tunable stiffness properties can yield dynamic haptic feedback and shape deformation capabilities. In comparison to the particle jamming, layer jamming allows for constructing thin and lightweight form factors of an interface. We propose five layer structure designs and an approach which composites multiple materials to control the deformability of the interfaces. We also present methods to embed different types of sensing and pneumatic actuation layers on the layer-jamming unit. Through three application prototypes we demonstrate the benefits of using layer jamming in interface design. Finally, we provide a survey of materials that have proven successful for layer jamming.

This paper presents PneUI, an enabling technology to build shape-changing interfaces through pneumatically-actuated soft composite materials. The composite materials integrate the capabilities of both input sensing and active shape output. This is enabled by the composites' multi-layer structures with different mechanical or electrical properties. The shape changing states are computationally controllable through pneumatics and pre-defined structure. We explore the design space of PneUI through four applications: height changing tangible phicons, a shape changing mobile, a transformable tablet case and a shape shifting lamp.

This paper presents a novel interactive installation "Jing Hua", which augments physical garden with virtual flowers. Visitors influence the growth of virtual flowers by manipulating a tangible interface: a white oversized bowl, on which the flowers are projected. The installation sought to explore how the physical environment and digital projection can be naturally merged to evoke subjects' mixed experience of aesthetics.