Yosuke Horiba

Virtual manipulations for draping

Purpose – Draping is one method used in clothing design. It is important to virtualize draping in real time, and virtual cloth handling is a key technology for this purpose. A mouse is often used for real-time cloth handling in many studies. However, gesture manipulation is more realistic than movements using the mouse. The purpose of this paper is to demonstrate virtual cloth manipulation using hand gestures in the real world. Design/methodology/approach – In this study, the authors demonstrate three types of manipulation: moving, cutting, and attaching. The user’s hand coordinates are obtained with a Kinect, and the cloth model is manipulated by them. The cloth model is moved based on the position of the hand coordinates. The cloth model is cut along a cut line calculated from the hand coordinates. In attaching the cloth model, it is mapped to a dummy model and then part of the cloth model is fixed and another part is released. Findings – This method can move the cloth model according to the motion of t...

Dynamic manipulation of a string using a manipulator-parameter identification and control based on a rigid body link model

Manipulation of deformable objects is an important subject for housekeeping and care robots. Dynamic manipulation of a string is studied in this paper as an example of deformable objects. The string is modeled by a rigid body link with passive joints in two-dimensional space. The parameters of the joint stiffness and viscosity of the string model are identified experimentally using a high-speed video camera. The desired trajectory of the manipulator is searched by using the optimal control method. The manipulator is controlled with the desired trajectory to manipulate the string. In this paper many experiments of flinging-up motion are conducted using two-link and three-link models of the string. The experimental results show the validity of the proposed method.

A preliminary study of a cloth guiding mechanism for automatic sewing system

Purpose – In the trend from mass production to mass customization, more flexible production systems are required. In the clothing field, many studies about automatization of sewing processes have been done into producing small amounts of various kinds of products. The purpose of this paper is to propose a versatile guiding mechanism of a cloth for an automatic sewing system.Design/methodology/approach – Real sewing processes were referenced for the mechanism, and curved stitch is formed holding a point on a cloth. This mechanism consists of a solenoid for holding a cloth and a roller to prevent deformation of the cloth. When a cloth is sewn with the mechanism, the trajectory of the stitch is unstable because of anisotropy of a cloth. A precise trajectory was obtained by adding a device to control the pressure of the roller for holding a cloth and keeping a tension properly applied to a cloth.Findings – It was found out that shearing property is the most related to the stability of sewing trajectory. If th...

Fabric Weave Form Simulation Based on the Characteristics of Yarn

The Property prediction of apparel textile based on the model of yarn structure is important. Especially, the prediction is important for the Kansei performance of textile products. It is necessary to create a model of the textile structure for predicting the physical properties of textiles. In this study the textile structure model is created based on the actual operation of the loom. The structural model of the textiles is composed of the yarn model. In this case, Breens particle model was used for the yarn model. In this study, by the above method, we created several models of fabrics. As a result, different fabric models are found to have a representation according to the characteristics of the structure of each thread. This method shows the possibility of simulating the characteristics of various fabrics made from yarn with different characteristics.

Study on interactive cloth simulation considering airflow

We propose the interactive cloth simulation considering airflow. For this purpose, the implicit method and airflow model are introduced. Also, a computer mouse and a microphone are used as the interface of handling and airflow. As a result, we could simulate the behavior of cloth depending on handling and airflow on real time

Heat balance model for a human body in the form of wet bulb globe temperature indices

The purpose of this study is to expand the empirically derived wet bulb globe temperature (WBGT) index to a rational thermal index based on the heat balance for a human body. We derive the heat balance model in the same form as the WBGT for a human engaged in moderate intensity work with a metabolic heat production of 174W/m2 while wearing typical vapor-permeable clothing under shady and sunny conditions. Two important relationships are revealed based on this derivation: (1) the natural wet bulb and black globe temperature coefficients in the WBGT coincide with the heat balance equation for a human body with a fixed skin wettedness of approximately 0.45 at a fixed skin temperature; and (2) the WBGT can be interpreted as the environmental potential to increase skin temperature rather than the heat storage rate of a human body. We propose an adjustment factor calculation method that supports the application of WBGT for humans dressed in various clothing types and working under various air velocity conditions. Concurrently, we note difficulties in adjusting the WBGT by using a single factor for humans wearing vapor-impermeable protective clothing. The WBGT for shady conditions does not need adjustment depending on the positive radiant field (i.e., when a radiant heat source exists), whereas that for the sunny condition requires adjustments because it underestimates heat stress, which may result in insufficient human protection measures.

Development of Virtual Draping System by Augmented Reality

The purpose of this study is to virtualize draping which is one of the methods to design paper patterns for clothing. It takes time and costs to make made-to-order clothing by draping method. If draping is virtualized, the processes to make made-to-order clothing become much more efficient. In our study, the components of the method such as cloth, hand and dress form are modeled. The cloth is modeled mechanically, and its dynamic shape is numerically calculated. Hand, also modeled, a sensor detects the motion of the hand or fingers in the real world, the data of the motion is transferred to a computer and the motion is reflected to the hand model. The dress form is also modeled as the basis to apply the cloth model to the surface of the dress form model. The intrusions of an element into another element are prevented by the detection and reaction of the collisions between those elements. The user of the system can manipulate the cloth model in the virtual world by moving hand or fingers in the real world. We are constructing a system in virtual environment. In the environment, the image of the real world is also projected. We are trying to superimpose virtual object on real object to improve the workability of the system.

Virtual draping by mapping

Abstract We propose a method of virtual draping by representing the actual draping process, i.e., a pattern is made a from cloth model by mapping. Additionally, the garment form is simulated from the obtained pattern. The process of making the pattern is as follows. A rectangular planar cloth model is made and slit for dart as needed. The slit cloth model is mapped to the surface of a dummy model. The shape of the cloth model under the condition of relaxation on the surface of the dummy model is obtained by mechanical calculation. A three-dimensional pattern shape is obtained to remove unnecessary part of the cloth model. Finally, a planar pattern shape is made by mapping the three-dimensional pattern inversely to a plane. A garment form is also simulated from the obtained pattern. The pattern for a pencil skirt can be made employing the proposed method. We make an actual pencil skirt and simulate its form using this pattern. Thus, the deformation of a cloth and the attaching process can be considered. The present study maps the cloth model to the dummy model to make the garment form and thus represents draping more closely.

A Virtual Cloth Manipulation System for Clothing Design

We have been studied virtualization of draping which is one of a design method for clothing. It is desirable to adopt a man-machine interface in the same way as the real world for virtual draping. For this purpose, motion of hand is detected by Leap Motion as a sensor. This sensor can detect not only the motion of hand but the motion of fingers. According to the motion of hand or fingers in the real world, hand model in the virtual world is moved. Cloth is modeled with simple particles and springs, and dynamical change of cloth model form is obtained by numerical integration of motion equation. The interaction between the hand model and the cloth model is enabled, and then it is possible to grab the cloth model by the hand model in the virtual world.

Handling of Virtual Cloth

In this study, manipulations of virtual cloth model were examined for draping. Cloth was mechanically formalized and modeled. Motion of real human hand is detected by a sensor and the motion is utilized for handling of the cloth model. Cloth manipulations to hold, release and attach were realized. When the cloth model is handling, “coarse model” and fast dynamic calculation method is used and when the cloth is at rest, “precise model” and precise static calculation method is used. When the cloth model is stopped from dynamic regime, the model of the cloth is switched from “coarse” to “precise”. When the model is started to move from static regime, the model of the cloth is switched from “precise” to “coarse”.