Due to the development of 3D food printers, it has become possible to print foods in various shapes without using molds. However, this method still has issues such as low printing resolution, limited printable shapes, and long printing time. Thus, 4D fabrication methods creating flat foods that change into arbitrary 3D shapes in response to external stimulation have been gaining more attention. In this research, we propose magashi, a 4D food printing method using rice flour paste. Off-the-shelf ingredients are mixed to make the paste which is printed by an extrusion-based printer and baked in an oven to make the flat material bend into 3D shapes. With our simple method users are able to print the material in different shapes with intricate patterns to customize their food. The printing material’s ingredients, printing patterns and thickness are adjusted to control the material’s drying process, causing it to bend upwards or downwards. In this paper, we describe the shape changing mechanism, fabrication method and producible shapes of magashi, as well as its applications.

We propose CoiLED Display, a stripe-shaped flexible display that can be wound around various objects. CoiLED Display is composed of a large number of chip LEDs arranged in a row, and the object wound by CoiLED can display image information. To recognize the configuration of display units wound around an object, the system conducts calibration by capturing the lighting of the LEDs with a camera and obtaining their relative positions with image processing. We evaluated the performance of the prototyped CoiLED Display from four aspects: processing time, refresh rate, power consumption, and physical flexibility. We then conducted a design study to evaluate the usability of the CoiLED Display and explored its application design space. The results suggest that the participants generally accepted our system, including the calibration process. In addition, the participants came up with a wide range of application area (e.g. wearable displays, public displays).

Personal fabrication allows users to create physical objects on their own. However, prototyping electric circuits are still challenging. We propose a fabricating technique for electric circuits based on hot stamping technology. It requires only a 3D printer with a ball caster and transfer foils so that the user can easily and cheaply print circuits on various materials. In this paper, we clarify the conditions for the proposed method and show the characteristics of the developed circuits and several examples of applications.

The manufacturing domain based on digital fabrication has attracted significant attention to create a diverse society. It has made it possible to realize “manufacturing for each individual and products for people close to them, ” which has been difficult toachieve with conventional mass products. Ontenna is an accessorydevice that provides a tactile and visual feedback of various sound information to the user. A condenser microphone mounted on the main body of Ontenna acquires the sound pressure and drives the vibration motor and light emitting diode in real-time according to the input signal. At present, 88 out of 102 schools belonging to the National Association of School Principals for the Deaf have installed the system. It is currently used for speech and rhythm education. We have developed a system that can change the color of the LEDs and the strength of the motor in Ontenna through programming. Additionally, we have made the system freely available to schools for the deaf and other educational institutions. We created an environment where children with hearing-impairment can overcome the obstacles they face at school by programming Ontenna themselves. In this study, we describe the development of the Ontenna programming function and our instructional plan created with teachers at a school for the deaf. We report the educational content (such as class slides and worksheets) that weredeveloped based on the plan. Finally, we present the results of the questionnaire survey and the experience diary conducted for schools that have implemented the Ontenna programming education environment. The results of the survey confirmed the advantages of Ontenna programming for education and its potential application to various other educational institutions.

Head-Related Transfer Function (HRTF) is an acoustic transfer function corresponding to sound transmission from a sound source to one’s ear in a free field. Its property depends on sound source position and difference in shapes of individual ear, head and torso and so on. Acquiring the HRTFs of a certain subject for multiple source positions based on measurement demands that the subject stationarily exists in the measurement system for a long time. It brings about serious physical burden to the subject, and causes some variance in the measured HRTFs. In order to resolve this difficulty, a 3D shape of the subject’s head and ears was scanned by using a 3D scanner and a digital camera, and the 3D data of the subject’s head was constructed. This is called “head model” in this paper. Then the head model was printed out by using a 3D printer, and the HRTFs of the subject were measured locating the head model instead of letting the subject be in the measurement system. As a fundamental investigation, a HATS (Head-and-Torso Simulator) was selected as a subject, and its HRTFs and those of its head model were measured in horizontal plane. As a result, the HRTFs measured for the head model of the HATS are an appropriate approximation with those of the HATS itself in the frequency range under 10 kHz, showing the possibility that the head model of the subject can be a substitute for the measurement of the subject’s HRTFs.

Wind displays are devices that enhance the presence of virtual reality (VR) by simulating realistic sensation of wind. However, certain wind displays require many wind sources because they reproduce fully physical wind directions. Methods to manipulate perceived directions of wind by cross-modal effects and realize wind displays with fewer wind sources have been proposed so far. We hypothesized that the visuoaudio-haptic cross-modal effect can enhance the effect of the manipulation. Thus we quantitatively investigated the effect of the congruent visual and audio information on the perceived wind directions. We present virtual images of flowing particles and threedimensional sounds of the wind as information to indicate “virtual” wind directions. The user study has shown that presenting both visual and audio information is significantly effective than presenting the audio or visual information alone. The median of absolute errors between the perceived wind directions and the virtual wind directions were 34.8° at most with the visual and audio information and the physical wind from front or behind.

With the development of engineering technology, many attempts have been made to persuade humans using engineering technology. Research on persuasion toward physical purposes using engineering technology has been conducted. For example, about changing attitudes toward purchasing products. On the other hand, for persuasion toward metaphysical purposes such as understanding abstract concepts and religious ideas, no methodology for using engineering technology has been established. This research aimed to realize persuasion toward metaphysical purposes. We focused on persuasion on the peripheral route in the elaboration likelihood model, and targeted transmission of Buddhist Doctrine as a metaphysical content. In order to achieve this, we have developed the media integrating an android and projection mapping. We discussed the relationship between the conventional media for transmission of Buddhist Doctrine and the developed system, and conducted the field experiment to verify the effectiveness of the developed system. As a result of the analysis, it was shown that the developed system could be effective for the transmission of Buddhist Doctrine. In the future, we plan to verify the effectiveness of the developed system outside of the transmission of Buddhism, and the synergistic effects that occur only by integrating an android and projection mapping in laboratory experiments.

In this paper, we propose Virtual Whiskers, a spatial directional guidance technique by stimulating a cheek using tiny robot arms attached to a Head-Mounted Display (HMD). We performed a directional guidance experiment to evaluate how accurately our method provide the target direction. The result shows our method achieves the average absolute directional error of 2.76 degrees in the azimuthal plane and 7.32 degrees in the elevation plane. We also investigated how effective the cheek stimulation is in a target search task. The average of task completion time in visual condition was M=12.45s, and visual+haptic condition resulted in M=6.91s. Statistical test revealed a significant difference between visual condition and visual+haptic condition.

This paper describes simple tactile presentation system for VR using magnetic field. Small devices that present a tactile sensation and can easily be mounted on skin have been proposed by attaching a magnet to a fingertip and setting a remote driving coil on the environment. However, such devices have been used only at a distance of several centimeters from the coil. We show that a coil of practical size and power consumption can convey sufficient vibration for tactile presentation at a distance of 50 cm or more, and two magnets can be driven almost independently by using multiple coils.

In this paper, we analyzed, concerning both angles and time responsibility, the data obtained in the experiment of the previous report about the back-of-hand electrical muscle stimulation (BoHEMS), adding a more detailed anatomical discussion. The analysis for the angles confirmed that the BoHEMS could efficiently flex fingers at only the MP joint, including the index finger, which was challenging to flex so far. Also, each finger flexed without a flexion around the PIP joint, which always occurs using EMS at the forearm, which many HCI researchers have often used for finger flexion. As for the time responsibility, the BoHEMS has a similar one as the conventional forearm EMS. We conclude that the BoHEMS is helpful for application for activities of daily living because of the selective MP joint flexion, which is of great importance for those. However, since the daily movement of the finger is not such simple, the flexor and extensor muscle stimulations in the forearm are needed to flex PIP joints in cooperation. Still, it is even difficult to flex the PIP joint of the index finger from the forearm; therefore, it is necessary to tackle it as a significant issue in the future.

In this paper, we propose a hand gesture sequence recognition technique for human–computer interactions wherein a user grasps an object. Our aim is to develop a technique which can recognize input in the form of various grasp types by recognizing their gesture sequence. We introduce a prototype using electromyography signals and report the results of a user study to validate the proposed technique for interactions in hands-busy situations and evaluate the recognition accuracy of the user gestures. The results demonstrate that our proposed technique showed 93.13% average accuracy for basic grasp types according to a classic taxonomy of grasping. We also discuss the findings of the user study and perspectives for the practical application of the proposed technique.

The development and widespread use of digital fabrication technology has facilitated the fabrication of 3D objects. By designing not only the external shape but also the internal structure and materials, it has become possible to add various functions such as sensing and actuation to objects. In this paper, we propose LayerPump as a novel design and fabrication method to create a pump function and a liquid flow path inside a 3D object using digital fabrication technology. Using a pump driven by Electrohydrodynamics (EHD), in which fluid moves in response to an electric field, we can design pumps with various shapes by creating an electric circuit according to its position and shape. In addition, we proposed a method of creating a layered plate structure to place the pump and flow paths at appropriate positions. Furthermore, we have realized a method to dynamically change the color, shape, and motion of objects by controlling the fluid flow using the EHD pump. In this paper, the design system, implementation, and applications of LayerPump are described in detail.