Using haptic feedback as an aid in the design of passive mechanisms

This paper presents a novel investigation of the effectiveness of haptic feedback for designing a class of interconnected multi-body systems such as passive mechanisms. The traditional application of haptic feedback in the design process has been in applications such as parts assembly or mold design. The design of the mechanism discussed in this paper is for applications where the user needs to manipulate the mechanism in order to interact with an environment. The objective of the design is to have the link ratios so that it can allow the user better movement control of the mechanism and thus give a better force amplification when there is a sudden change in the contact reaction force with the application environment. A haptic device is used as a design interface between the designer of such mechanisms and the virtual mechanism model. For this preliminary investigation, we used a four-bar mechanism. In our case study, we choose, as an example, to use the net distance travel of a tool when penetrating inside a model of a deformable surface as the design objective to minimize. The effects on the variation of this distance travelled can then be studied by adjusting some of the key design parameters used in the mechanism. To evaluate our proposed haptic-aided design environment, an informal preliminary user study was conducted, where each subject explored a sampled design space of the mechanism. The results of the user study suggest that the usage of a haptic device in the design of this class of mechanism can expedite the design process.     

Touch and design: novel haptic interfaces for the generation of high quality surfaces for industrial design

This paper presents the results of a research project aimed at developing haptic tools for virtual shape modelling resembling real tools like rakes and sandpaper used by modelers and designers in the real workshop. The developed system consists of a CAD (computer aided design) system enhanced with intuitive designer-oriented interaction tools and modalities. The system requirements have been defined on the basis of the observation of designers during their daily work, and translating the way they model shapes using hands and craft tools into specifications for the modelling system based on haptic tools.     

A reverse engineering method based on haptic volume removing

This paper presents a new reverse engineering methodology that is based on haptic volume removing. When a physical object is to be digitized, it is first buried in a piece of virtual clay that is generated with the help of a fixture. Now digitizing the physical object is by simply chipping away the virtual clay with a position tracker that is attached to a haptic device PHANToM^®. While chipping away the clay, the user can see on the computer monitor what is emerging and at the same time feel the chipping force from the haptic device. By so doing, reverse engineering is seamlessly integrated into haptic volume sculpting that is now widely used for conceptual design. Furthermore, the proposed method has eliminated the need to merge point clouds that are digitized from different views using current digitizers. The virtual clay volume is represented by a spatial run-length encoding scheme. A prototype system has been developed to demonstrate the feasibility of the proposed new method through a case study. The strengths and weaknesses of the presented method are analyzed and the applicability is discussed.     

System for interactive scientific driving simulation with haptic information

An interactive wheeled vehicle simulator is described, consisting of a software application for simulating vehicle dynamics and presenting the results in virtual 3D environment, and a haptic interface. The latter consists of a hydraulically actuated active seat and an electrically activated active steering wheel. The system makes it possible to simulate wheeled vehicles of various configurations on arbitrary terrains. The design of the system is presented and the specific considerations are discussed. The system was experimentally verified by measurements on a real off-road vehicle. The kinematic values measured on the real vehicle and those, measured on the haptic interface were compared. The results are discussed and are generally found to correspond well, making the system usable for studying vehicle performance and training its operators.     

Adaptive haptic rendering for time‐varying haptic and video frame rates in multi‐modal interactions

In multi‐modal interactions including haptics, problems such as input sensor noise, temporal mismatch between graphics and haptics, and non‐constant refresh rates may cause non‐smooth force/torque display. This paper proposes temporal smoothing technique for haptic interaction using a sensing glove in multi‐modal applications. The proposed technique employs two processes: (1) a noise reduction method is applied to reduce jitter noise at the sensors in the sensing glove and (2) an adaptive force extrapolation is applied for time‐varying haptic and video frame rates. To demonstrate the performance of the proposed method, we developed a test platform to assess a simple box model and relatively complex models such as gamephone, portable media player (PMP). It was subsequently demonstrated that the proposed method can support smooth haptic interactions in multi‐modal applications where a haptic device and a sensing glove are used. Copyright © 2009 John Wiley & Sons, Ltd.     

Creative parameter selection for volume visualization

Most of the available algorithms for scalar volume visualization offer predefined techniques such as display of volumetric regions defined by scalar threshold values. The regions can usually be drawn opaque or transparent or appear in combinations. This paper presents an implementation of a volume visualization concept where several modelling and rendering techniques can be applied in any combination, mainly bounded by the creativity of the user. The concept is based on the use of a model for light scattering in a field of varying density emitters, and the use of fixed visual references to improve readability and disambiguate interpretation. An image is computed by means of an interval-based mapping from scalar range to visual parameters. Each interval has a set of associated parameters, such as colour and attenuation. In addition, each interval of the scalar range must be mapped into relative density by means of a transfer function which is selected in a ‘natural way’ depending on application. A methodology is suggested which enable the piecewise transfer functions to be easily determined. A prototype user-interface for the mapping from scalar values to visual parameters is demonstrated. The interface is easy to use for the beginner, while it also encourages creativity and intuition in the process of selecting parameters.     

Simplifying interactive design of solid models: A hypertext approach

Conceptual design and editing parameterized models of 3D solids often requires user interactions with many types of entities and relations. In this paper, we present a concept for simplifying the design process. The simplification is based on three paradigms; integration of data structures and control structures, multiple view interface, and use of hypertext techniques for fast traversal and selective display of data. Data structures and control structures are integrated into uniform building blocks called cells. Cells define assemblies of CSG solids and can be grouped bottom-up into more complex cells or, alternatively, can be refined top-down during the design process. Efficient specification of complex cells and patterns is made possible through the use of automatic default values, multiple instantiation, built-in repetition, and recursion. A multiple-view interface enables the designer to view and edit both the cell parameters and the hierarchical structure of the model. The interface provides integrated textual, 2D graphical, and 3D direct-manipulation techniques for specifying primitive dimensions and relative transformations.     

Iterative process of design and evaluation of icons for interactive TV menu

This paper shows an iterative process of design and evaluation of icons for future interactive TV services. In doing the RNRT (French National Network of Research in Telecommunications) iTV project, we tried to generate icons easy to identify, associate and memorise for 32 categories and services of our iTV system.

Through an iterative process, the Multiple Index Approach was applied until an acceptable icon set was achieved. In addition to existing evaluation criteria such as the intuitiveness, associativeness, preference and suitability with subjective certainty of users, we emphasised the importance of the learnability measured by recall tests.

As a conclusion, we propose a methodology of icon design and evaluation for information appliances that integrate unfamiliar features with common users.     

Iterative process of design and evaluation of icons for interactive TV menu

This paper shows an iterative process of design and evaluation of icons for future interactive TV services. In doing the RNRT (French National Network of Research in Telecommunications) iTV project, we tried to generate icons easy to identify, associate and memorise for 32 categories and services of our iTV system.

Through an iterative process, the Multiple Index Approach was applied until an acceptable icon set was achieved. In addition to existing evaluation criteria such as the intuitiveness, associativeness, preference and suitability with subjective certainty of users, we emphasised the importance of the learnability measured by recall tests.

As a conclusion, we propose a methodology of icon design and evaluation for information appliances that integrate unfamiliar features with common users.     

Application of interactive genetic algorithm to fashion design

In general, computer-aided design support systems have got an approach of traditional artificial intelligence, which statistically analyzes data such as the behavior of designer, to extract formal design behavior. This approach, however, can neither deal with continuous change of fashion nor reflect personal taste well, as it just depends on large amount of collected data. To overcome this sort of problem interactive genetic algorithm (IGA) has been recently proposed, as a new trend of evolutionary computation. IGA uses human's response as fitness value when the fitness function cannot be explicitly defined. This enables IGA to be applied to artistic domains, and we propose a fashion design aid system using it. Unlike the previous works that attempt to model the dress design by several spline curves, the proposed system is based on a new encoding scheme that practically describes a dress with three parts: body and neck, sleeve, and skirt. By incorporating the domain-specific knowledge into the genotype, we could develop a more realistic design aid system for women’s dress. We have implemented the system with OpenGL and VRML to enhance the system interface. The experiments with several human subjects show that the IGA approach to dress design aid system is promising.     

The implementation and evaluation of a virtual haptic back

A virtual haptic back (VHB) model has been developed by a cross-disciplinary team of researchers at Ohio University. Haptics give the human the sense of touch and force from virtual computer models. The objective is to create a tool for medical and related education whereby students can train in the difficult art of palpation using virtual reality before approaching human subjects. Palpation is the art of medical diagnosis through the sense of touch. Haptic anatomy could be a key area in the future of medical school training; our goal is to add science to the art of palpation to improve osteopathic, physical therapy and massage therapy training for students and practitioners. Modelling of the VHB took place in two steps. First, Cartesian back data was collected via the Metrecom Skeletal Analysis System (SAS) digitiser. The back of a prone human subject was digitised, giving an array of three-dimensional points. Several methods were considered to smooth out the back data. Spline fitting with matched first and second derivates was the chosen method. Once an acceptable graphical model was created, haptic feedback was added using the PHANToM haptic interface, allowing the human user to explore and feel the virtual back. Experienced and novice palpators formally evaluated the VHB to give us feedback for improvements. In addition, four Doctors of Osteopathy informally interacted with our model and gave verbal feedback. Our experts all suggested modelling underlying muscles and skeletal structure in addition to the skin layer for more realism. Once this is accomplished we will further program somatic dysfunction of various types in the VHB for students to diagnose. This article contributes to the state of the art in virtual haptic anatomy. While other research groups are working in this area, our work is the first specifically aimed towards osteopathic medicine, physical therapy, and massage therapy students and practitioners.     

Improving virtual reality navigation tasks using a haptic vest and upper body tracking

Haptic feedback is an important component of immersive virtual reality (VR) applications that is often suggested to complement visual information through the sense of touch. This paper investigates the use of a haptic vest in navigation tasks. The haptic vest produces a repulsive vibrotactile feedback from nearby static virtual obstacles that augments the user spatial awareness. The tasks require the user to perform complex movements in a 3D cluttered virtual environment, like avoiding obstacles while walking backwards and pulling a virtual object. The experimental setup consists of a room-scale environment. Our approach is the first study where a haptic vest is tracked in real time using a motion capture device so that proximity-based haptic feedback can be conveyed according to the actual movement of the upper body of the user.User study experiments have been conducted with and without haptic feedback in virtual environments involving both normal and limited visibility conditions. A quantitative evaluation was carried out by measuring task completion time and error (collision) rate. Multiple haptic rendering techniques have also been tested. Results show that under limited visibility conditions proximity-based haptic feedback generated by a wearable haptic vest can significantly reduce the number of collisions with obstacles in the virtual environment.     

Identifying the effectiveness of using three different haptic devices for providing non-visual access to the web

Haptic technologies are often used to improve access to the structural content of graphical user interfaces, thereby augmenting the interaction process for blind users. While haptic design guidelines offer valuable assistance when developing non-visual interfaces, the recommendations presented are often tailored to the feedback produced via one particular haptic input/output device. A blind user is therefore restricted to interacting with a device which may be unfamiliar to him/her, rather than selecting from the range of commercially available products. This paper reviews devices available on the first and second-hand markets, and describes an exploratory study undertaken with 12 blindfolded sighted participants to determine the effectiveness of three devices for non-visual web interaction. The force-feedback devices chosen for the study, ranged in the number of translations and rotations that the user was able to perform when interacting with them. Results have indicated that the Novint Falcon could be used to target items faster in the first task presented, compared with the other devices. However, participants agreed that the force-feedback mouse was most comfortable to use when interacting with the interface. Findings have highlighted the benefits which low cost haptic input/output devices can offer to the non-visual browsing process, and any changes which may need to be made to accommodate their deficiencies. The study has also highlighted the need for web designers to integrate appropriate haptic feedback on their web sites to cater for the strengths and weaknesses of various devices, in order to provide universally accessible sites and online applications.     

A method for product form design of integrating interactive genetic algorithm with the interval hesitation time and user satisfaction

Due to the continuous release of new products, manufacturers are paying attention to customer-oriented design of products that meet user needs to minimize the risk of their products being rejected by the market. Due to the ambiguity of user cognition, it is difficult to accurately obtain the user's preference for individual productions. To respond to the challenge, we propose an engineering scientific research method of interactive genetic algorithm with the interval arithmetic based on hesitation and fuzzy kano model(FKM) to explore the emotional needs of users for product forms and drive product modeling evolution design. Through expert interviews, the morphological characteristics and perceptual images factors of the products attracting users are investigated. In order to identify the user's satisfaction relationship with the perceptual images, we use FKM to analyze the product image style that meets the user's kansei needs accurately and selects 5 factors which is attractive attributes. Meanwhile, we attempt to transform this 5 factors into evaluation carrier to guide the evolution direction of product styling in HIIF-IGA, and then optimized four electric bikes with scores over 8.8 so that it could realize user demand-driven product evolution design. To handle users' ambiguity, the FAHP method is used to quantify the user's emotional imagery criterion and create a product evolution design system platform, which can automatically generate product styling design scheme in line with user preferences. This experimental results show that the proposed method can help enterprises effectively improve customer satisfaction and reduce the cost and time of product development.     

一种居住区位和通勤交通方式的组合选择模型

为了研究通勤交通方式对就业者选择居住区位的影响,基于交叉分层的Logit模型建立了居住区位和通勤交通方式的组合选择模型。以不同通勤距离为半径作居住区位选择环域集,以通勤交通方式和居住区位的两两组合为模型选择项集合,以就业者社会经济属性、居住成本、通勤成本为特征变量建立概率选择模型。根据调查数据,采用阶段计算法对特征变量和模型参数进行标定和检验。测试结果表明:通勤时间、通勤费用和居住成本与选择项关系密切;收入较高且拥有小汽车的就业者对于居住区位选择的灵活性较大。     

Influences of haptic communication on a shared manual task

With the advent of new haptic feedback devices, researchers are giving serious consideration to the incorporation of haptic communication in collaborative virtual environments. For instance, haptic interactions based tools can be used for medical and related education whereby students can train in minimal invasive surgery using virtual reality before approaching human subjects. To design virtual environments that support haptic communication, a deeper understanding of humans′ haptic interactions is required. In this paper, human′s haptic collaboration is investigated. A collaborative virtual environment was designed to support performing a shared manual task. To evaluate this system, 60 medical students participated to an experimental study. Participants were asked to perform in dyads a needle insertion task after a training period. Results show that compared to conventional training methods, a visual-haptic training improves user′s collaborative performance. In addition, we found that haptic interaction influences the partners′ verbal communication when sharing haptic information. This indicates that the haptic communication training changes the nature of the users′ mental representations. Finally, we found that haptic interactions increased the sense of copresence in the virtual environment: haptic communication facilitates users′ collaboration in a shared manual task within a shared virtual environment. Design implications for including haptic communication in virtual environments are outlined.     

Multi-modal virtual environments for education with haptic and olfactory feedback

It has been suggested that immersive virtual reality (VR) technology allows knowledge-building experiences and in this way provides an alternative educational process. Important key features of constructivist educational computer-based environments for science teaching and learning, include interaction, size, transduction and reification. Indeed, multi-sensory VR technology suits very well the needs of sciences that require a higher level of visualization and interaction. Haptics that refers to physical interactions with virtual environments (VEs) may be coupled with other sensory modalities such as vision and audition but are hardly ever associated with other feedback channels, such as olfactory feedback. A survey of theory and existing VEs including haptic or olfactory feedback, especially in the field of education is provided. Our multi-modal human-scale VE VIREPSE (virtual reality platform for simulation and experimentation) that provides haptic interaction using a string-based interface called SPIDAR (space interface device for artificial reality), olfactory and auditory feedbacks is described. An application that allows students experiencing the abstract concept of the Bohr atomic model and the quantization of the energy levels has been developed. Different configurations that support interaction, size and reification through the use of immersive and multi-modal (visual, haptic, auditory and olfactory) feedback are proposed for further evaluation. Haptic interaction is achieved using different techniques ranging from desktop pseudo-haptic feedback to human-scale haptic interaction. Olfactory information is provided using different fan-based olfactory displays (ODs). Significance of developing such multi-modal VEs for education is discussed.     

On the development of a haptic system for rapid product development

This paper presents a system development that extends haptic modeling to a number of key aspects in product development. Since haptic modeling has been developed based on physical laws, it is anticipated that a natural link between the virtual world and practical applications can be established based on haptic interaction. In the proposed system, a haptic device is used as the central mechanism for reverse engineering, shape modeling, real time mechanical property analysis, machining tool path planning and coordinate measuring machine (CMM) tolerance inspection path planning. With all these features in a single haptic system, it is possible to construct a three dimensional part by either haptic shape modeling or reverse engineering, then performing real-time mechanical property analysis in which the stiffness of a part can be felt and intuitively evaluated by the user, or generating collision free cutter tool path and CMM tolerance inspection path. Due to the force feed back in all of the above activities, the product development process is more intuitive, efficient and user-friendly. A prototype system has been developed to demonstrate the proposed capabilities.