Shape Localization and Recognition using a Magnetorheological-fluid Haptic Display

Smart materials such as magnetorheological fluids (MRF) offer an interesting technology for use in haptic displays as changes in the magnetic field are rapid, reversible, and controllable. These interfaces have been evaluated in a number of medical and surgical simulators where they can provide cues regarding the viscoelastic properties of tissues. The objective of the present set of experiments was first to determine whether a shape embedded in the MRF could be precisely localized and second whether 10 shapes rendered in a MRF haptic display could be accurately identified. It was also of interest to determine how the information transfer associated with this type of haptic display compares to that achieved using other haptic channels of communication. The overall performance of participants at identifying the shapes rendered in the MRF was good with a mean score of 73 percent correct and an Information Transfer (IT) of 2.2 bits. Participants could also localize a rigid object in the display accurately. These findings indicate that this technology has potential for use in training manual palpation skills and in exploring haptic shape perception in dynamic environments

Shape Localization and Recognition Using a Magnetorheological-Fluid Haptic Display

Smart materials such as magnetorheological fluids (MRF) offer an interesting technology for use in haptic displays as changes in the magnetic field are rapid, reversible, and controllable. These interfaces have been evaluated in a number of medical and surgical simulators where they can provide cues regarding the viscoelastic properties of tissues. The objective of the present set of experiments was first to determine whether a shape embedded in the MRF could be precisely localized and second whether 10 shapes rendered in a MRF haptic display could be accurately identified. It was also of interest to determine how the information transfer associated with this type of haptic display compares to that achieved using other haptic channels of communication. The overall performance of participants at identifying the shapes rendered in the MRF was good with a mean score of 73 percent correct and an Information Transfer (IT) of 2.2 bits. Participants could also localize a rigid object in the display accurately. These findings indicate that this technology has potential for use in training manual palpation skills and in exploring haptic shape perception in dynamic environments

Active-Proprioceptive-Vibrotactile and Passive-Vibrotactile Haptics for Navigation

Navigation is a complex activity and an enabling skill that humans take for granted. It is vital for humans as it fosters spatial awareness, enables exploration, facilitates efficient travel, ensures safety, supports daily activities, promotes cognitive development, and provides a sense of independence. Humans have created tools for diverse activities, including navigation. Usually, these tools for navigation are vision-based, but for situations where visual channels are obstructed, unavailable, or are to be complemented for immersion or multi-tasking, touch-based tools exist. These touch-based tools or devices are called haptic displays. Many different types of haptic displays are employed by a range of fields from telesurgery to education and navigation. In the context of navigation, certain classes of haptic displays are more popular than others, for example, passive multi-element vibrotactile haptic displays, such as haptic belts. However, certain other classes of haptic displays, such as active proprioceptive vibrotactile and passive single-element vibrotactile, may be better suited for certain practical situations and may prove to be more effective and intuitive for navigational tasks than a popular option, such as a haptic belt. However, these other classes have not been evaluated and cross-compared in the context of navigation. This research project aims to contribute towards the understanding and, consequently, the improvement of designs and user experience of navigational haptic displays by thoroughly evaluating and cross-comparing the effectiveness and intuitiveness of three classes of haptic display (passive single-element vibrotactile; passive multi-element vibrotactile; and various active proprioceptive vibrotactile) for navigation. Evaluation and cross-comparisons take into account quantitative measures, for example, accuracy, response time, number of repeats taken, experienced mental workload, and perceived usability, as well as qualitative feedback collected through informal interviews during the testing of the prototypes. Results show that the passive single-element vibrotactile and active proprioceptive vibrotactile classes can be used as effective and intuitive navigational displays. Furthermore, results shed light on the multifaceted nature of haptic displays and their impact on user performance, preferences, and experiences. Quantitative findings related to performance combined with qualitative findings emphasise that one size does not fit all, and a tailored approach is necessary to address the varying needs and preferences of users