19 research outputs found
Interacting with Acoustic Simulation and Fabrication
Incorporating accurate physics-based simulation into interactive design tools
is challenging. However, adding the physics accurately becomes crucial to
several emerging technologies. For example, in virtual/augmented reality
(VR/AR) videos, the faithful reproduction of surrounding audios is required to
bring the immersion to the next level. Similarly, as personal fabrication is
made possible with accessible 3D printers, more intuitive tools that respect
the physical constraints can help artists to prototype designs. One main hurdle
is the sheer amount of computation complexity to accurately reproduce the
real-world phenomena through physics-based simulation. In my thesis research, I
develop interactive tools that implement efficient physics-based simulation
algorithms for automatic optimization and intuitive user interaction.Comment: ACM UIST 2017 Doctoral Symposiu
Inflatable actuators based on machine embroidery
The growing interest in wearable technologies has prompted the development of new techniques for integrating electronics into garments, and more specifically to overcome the challenges interfacing hard and soft components. In comparison to sensors and leads, the textile-based or integrated solutions for actuation remain underexplored. Approaching materials as extensions of actuators, we investigate machine embroidery as means to integrate silicone-based inflatables into garments. Following a research through design methodology, we created inflatables whose design and behavior are determined by machine embroidered substrates. Our iterative process resulted in 24 samples, divided in five series, exploring distinct challenges: 1) sewing attributes to create properties of inflatables; 2) fit & support; 3) improving integration
& resolution of complex shapes; 4) enlarging area of actuation; and 5) textile integration. We discuss the
impact of different parameters to the fabrication and the interaction possibilities of soft actuators. We show how machine embroidery allows shifting the complexity of the designs away from the casting process, simplifying fabrication, while enabling the creation of a wide range of shapes and behaviors through layering of textile structures. Our work extends the possibilities of integrating different technologies into garments through a single manufacturing process. We contribute with the detailed description of our design process and reflections on designing inflatables by means of machine embroidery
Shape sensing of variable stiffness soft robots using electrical impedance tomography
Soft robotic systems offer benefits over traditional rigid systems through reduced contact trauma with soft tissues and by enabling access through tortuous paths in minimally invasive surgery. However, the inherent deformability of soft robots places both a greater onus on accurate modelling of their shape, and greater challenges in realising intraoperative shape sensing. Herein we present a proprioceptive (self-sensing) soft actuator, with an electrically conductive working fluid. Electrical impedance measurements from up to six electrodes enabled tomographic reconstructions using Electrical Impedance Tomography (EIT). A new Frequency Division Multiplexed (FDM) EIT system was developed capable of measurements of 66 dB SNR with 20 ms temporal resolution. The concept was examined in two two-degree-of-freedom designs: a hydraulic hinged actuator and a pneumatic finger actuator with hydraulic beams. Both cases demonstrated that impedance measurements could be used to infer shape changes, and EIT images reconstructed during actuation showed distinct patterns with respect to each degree of freedom (DOF). Whilst there was some mechanical hysteresis observed, the repeatability of the measurements and resultant images was high. The results show the potential of FDM-EIT as a low-cost, low profile shape sensor in soft robots
Thin soft layered actuator based on a novel fabrication technique
This paper presents a novel fabrication method for constructing thin soft layered actuators. The method is based on building up thin layers of elastomeric material with embedded strain-limiting and mask layers using a bespoke film applicator. This enables the fabrication of millimetre-scale soft actuators with complex integrated masks and/or strain-limiting layers, as demonstrated in a series of proof of concept prototypes. The prototype actuators can be cut into a desired shape via laser cutting the laminated sheet. This paper shows the feasibility of the fabrication method and the value of its use in creating thin soft layered actuators for application in soft robotics. The technique can be further developed to fabricate multi-material composite soft actuators which are thin, compact, flexible and stretchable
LiftTiles: Constructive Building Blocks for Prototyping Room-scale Shape-changing Interfaces
Large-scale shape-changing interfaces have great potential, but creating such
systems requires substantial time, cost, space, and efforts, which hinders the
research community to explore interactions beyond the scale of human hands. We
introduce modular inflatable actuators as building blocks for prototyping
room-scale shape-changing interfaces. Each actuator can change its height from
15cm to 150cm, actuated and controlled by air pressure. Each unit is low-cost
(8 USD), lightweight (10 kg), compact (15 cm), and robust, making it
well-suited for prototyping room-scale shape transformations. Moreover, our
modular and reconfigurable design allows researchers and designers to quickly
construct different geometries and to explore various applications. This paper
contributes to the design and implementation of highly extendable inflatable
actuators, and demonstrates a range of scenarios that can leverage this modular
building block.Comment: TEI 202
Programming stiff inflatable shells from planar patterned fabrics
Lack of stiffness often limits thin shape-shifting structures to small
scales. The large in-plane transformations required to distort the metrics are
indeed commonly achieved by using soft hydrogels or elastomers. We introduce
here a versatile single-step method to shapeprogram stiff inflated structures,
opening the door for numerous large scale applications, ranging from space
deployable structures to emergency shelters. This technique relies on channel
patterns obtained by heat-sealing superimposed flat quasi-inextensible fabric
sheets. Inflating channels induces an anisotropic in-plane contraction and thus
a possible change of Gaussian curvature. Seam lines, which act as a director
field for the in-plane deformation, encode the shape of the deployed structure.
We present three patterning methods to quantitatively and analytically program
shells with non-Euclidean metrics. In addition to shapes, we describe with
scaling laws the mechanical properties of the inflated structures. Large
deployed structures can resist their weight, substantially broadening the
palette of applications.Comment: 6 pages, 4 figures and Supplementary Information (14 pages, 3
figures
ACM Transactions on Graphics
We present a computational approach for designing CurveUps, curvy shells that form from an initially flat state. They consist of small rigid tiles that are tightly held together by two pre-stretched elastic sheets attached to them. Our method allows the realization of smooth, doubly curved surfaces that can be fabricated as a flat piece. Once released, the restoring forces of the pre-stretched sheets support the object to take shape in 3D. CurveUps are structurally stable in their target configuration. The design process starts with a target surface. Our method generates a tile layout in 2D and optimizes the distribution, shape, and attachment areas of the tiles to obtain a configuration that is fabricable and in which the curved up state closely matches the target. Our approach is based on an efficient approximate model and a local optimization strategy for an otherwise intractable nonlinear optimization problem. We demonstrate the effectiveness of our approach for a wide range of shapes, all realized as physical prototypes
Facilitating Self-monitored Physical Rehabilitation with Virtual Reality and Haptic feedback
Physical rehabilitation is essential to recovery from joint replacement
operations. As a representation, total knee arthroplasty (TKA) requires
patients to conduct intensive physical exercises to regain the knee's range of
motion and muscle strength. However, current joint replacement physical
rehabilitation methods rely highly on therapists for supervision, and existing
computer-assisted systems lack consideration for enabling self-monitoring,
making at-home physical rehabilitation difficult. In this paper, we
investigated design recommendations that would enable self-monitored
rehabilitation through clinical observations and focus group interviews with
doctors and therapists. With this knowledge, we further explored Virtual
Reality(VR)-based visual presentation and supplemental haptic motion guidance
features in our implementation VReHab, a self-monitored and multimodal physical
rehabilitation system with VR and vibrotactile and pneumatic feedback in a TKA
rehabilitation context. We found that the third point of view real-time
reconstructed motion on a virtual avatar overlaid with the target pose
effectively provides motion awareness and guidance while haptic feedback helps
enhance users' motion accuracy and stability. Finally, we implemented
\systemname to facilitate self-monitored post-operative exercises and validated
its effectiveness through a clinical study with 10 patients
MotorSkinsâa bio-inspired design approach towards an interactive soft-robotic exosuit
The work presents a bio-inspired design approach to a soft-robotic solution for assisting the knee-bending in users with reduced mobility in lower limbs. Exosuits and fluid-driven actuators are fabric-based devices that are gaining increasing relevance as alternatives assistive technologies that can provide simpler, more flexible solutions in comparison with the rigid exoskeletons. These devices, however, commonly require an external energy supply or a pressurized-fluid reservoir, which considerably constrain the autonomy of such solutions. In this work, we introduce an event-based energy cycle (EBEC) design concept, that can harvest, store, and release the required energy for assisting the knee-bending, in a synchronised interaction with the user and the environment, thus eliminating any need for external energy or control input. Ice-plant hydro-actuation system served as the source of inspiration to address the specific requirements of such interactive exosuit through a fluid-driven material system. Based on the EBEC design concepts and the abstracted bio-inspired principles, a series of (material and process driven) design experimentations helped to address the challenges of realising various functionalities of the harvest, storage, actuation and control instances within a closed hydraulic circuit. Sealing and defining various areas of water-tight seam made out of thermoplastic elastomers provided the base material system to program various chambers, channels, flow-check valves etc of such EBEC system. The resulting fluid-driven EBEC-skin served as a proof of concept for such active exosuit, that brings these functionalities into an integrated âsense-actingâ material system, realising an auto-synchronised energy and information cycles. The proposed design concept can serve as a model for development of similar fluid-driven EBEC soft-machines for further applications. On the more general scheme, the work presents an interdisciplinary design-science approach to bio-inspiration and showcases how biological material solutions can be looked at from a design/designer perspective to bridge the bottomâup and topâdown approach to bio-inspiration.Deutsche Forschungsgemeinschafthttps://doi.org/10.13039/501100001659Peer Reviewe