Markus N. Montandon’s research while affiliated with University of Utah and other places

Our lab has developed a haptic feedback device to provide ungrounded tactile feedback through the motion of actuated sliding plate contactors. Interaction with a virtual environment is provided to a user through a device equipped with tactile feedback and six degree-of-freedom spatial position sensing. Our tactile feedback device is composed of three sliding plate skin stretch displays positioned around the handle, providing feedback to a user's palm. Our dual-handed tactile feedback system allows independent motion of hands, while providing feedback that creates a kinesthetic experience. We demonstrate fundamental physical interactions such as mass, spring, and damper interactions, which are the building blocks used in every virtual model. Various virtual environments are used to demonstrate physical interactions with objects.

Summary form only given. Interaction with a virtual environment will be provided to a user through a device equipped with tactile feedback and six degree-of-freedom spatial position sensing. Our tactile feedback device uses three sliding plates positioned around the handle to provide skin stretch feedback to a user's palm. Our two-handed tactile feedback device allows for independent hand motions and while providing tactile feedback creates a feedback experience that is more kinesthetic in nature. Our device and demonstrations include cooperative multi-handed interactions that portray fundamental physical interactions such as mass, stiffness, and damping. These physical interactions are fundamental as they are the building blocks of virtually every dynamic model. Various virtual environments will be used to demonstrate these physical interactions.

This paper presents a device for providing tactile feedback through four sliding contactor plates placed in the device's handle and grasped in the palm of the hand. This device is capable of communicating virtual forces and torques to a user through the motion of the independently controlled slider plates. Integrated device motion tracking allows simulation software to command our haptic device to mimic the in-hand friction and shear forces experienced by a user during sports activities such as swinging a tennis racket or catching a lacrosse ball. These situations present the user with the resistance of rotational inertia and impact torques. We present two experiments that provide an initial characterization of the range of rotational inertia and impact torques that can be presented with the current prototype. Weber fractions for discriminating rotational inertia and torque in the two experiments ranged from 15-25%. Such feedback can be used to give the sense of mass to a virtual object.

This paper presents the design and development of a novel device for providing tactile feedback in five degrees of freedom (5-DOF). Four translational and four rotational motions of the hand can be communicated to a user using two independently controlled 2-DOF skin stretch feedback devices placed back-to-back. An additional two rotational motions of the hand can be communicated through spiral motions of the two skin stretch feedback devices. The user's index finger and thumb grasp the device at the location of the moving contactor (tactor) of each of the 2-DOF skin stretch displays, respectively. Experiments show user responses to have high directional accuracy (> 98%) for each of the five degrees of freedom communicated by the device. A second experiment also shows a proof of concept for using the back-to-back skin stretch display to guide users' hand motions to match a specified target angle in a one degree-of-freedom wrist rotation task. Findings from this preliminary study will be used in future studies to investigate users' ability to track paths in multiple degrees of freedom or to direct the hand motions of a user, which could be relevant to tasks such as upper limb rehabilitation, swing training, or other motion training.

We have developed and calibrated a bi-manual smartphone peripheral for rendering skin stretch feedback to a user's thumbs. The device's compact skin stretch displays are capable of providing repeatable haptic cues to a variety of users. Results from single- and dual-handed direction identification tests for judging 16 equally distributed direction cues show significantly better performance when the user is simultaneously provided with a direction cue on both thumbs.

This paper presents the design and development of handheld gaming devices that provide a new form of touch feedback: skin stretch feedback. Our prior work showed 1-1.5 mm of skin stretch applied to the fingertips (or thumb tips) could provide direction cues with high accuracy. The direction of each cue corresponded to the direction of applied skin stretch. Haptic feedback via tactile skin stretch can be used to provide tactile gaming effects and directional information through the same interface used for game inputs. Tests conducted with devices that resemble modern game controllers indicated which grip style is preferred by users and how to present direction cues to achieve the highest recognition rates. The main contribution of this paper is to show an initial demonstration of the benefits of skin stretch feedback in a multimodal gaming scenario.

Haptic devices have the ability to convey information to users through touch. Often, this method of communication can be preferable to more traditional means of communication, such as visual or audio displays. For example, a haptic device could provide directional skin stretch to communicate navigational cues as an alternative to audio commands. Prior work has shown that directional skin stretch applied on the fingertips can be accurately recognized with displacements less than 0.2 mm. While the fingertips excel at accurately discerning direction cues, it is often desirable to leave the fingers unencumbered for other tasks. This desire has motivated an effort to explore other locations to which direction cues can be applied. Studies of human sensitivity indicate that the hand or forearm may be a good location for skin stretch cues. Based on this information, a portable device was designed that applies direction cues to the forearm. The process of designing this device began with testing to estimate the magnitude of skin stretch required to accurately convey direction cues for a variety of forearm and hand locations. Based on these results, a forearm-mounted skin stretch prototype capable of 2 mm skin displacements was designed and fabricated. A qualitative evaluation of an initial prototype contributed several useful insights that aided in the design of the final device prototype.