Space agencies are in the process of drawing up carefully thought-out Concepts of Operations (ConOps) for future human missions on the Moon. These are typically assessed and validated through costly and logistically demanding analogue field studies. While interactive simulations in Virtual Reality (VR) offer a comparatively cost-effective alternative, they have faced criticism for lacking the fidelity of real-world deployments. This paper explores the applicability of passive haptic interfaces in bridging the gap between simulated and real-world ConOps assessments. Leveraging passive haptic props (equipment mockup and astronaut gloves), we virtually recreated the Apollo 12 mission procedure and assessed it with experienced astronauts and other space experts. Quantitative and qualitative findings indicate that haptics increased presence and embodiment, thus improving perceived simulation fidelity and validity of user reflections. We conclude by discussing the potential role of passive haptic modalities in facilitating early-stage ConOps assessments for human endeavours on the Moon and beyond.
doi.org/10.1145/3613904.3642292
Wrist-based input often requires tuning parameter settings in correspondence to between-user and between-session differences, such as variations in hand anatomy, wearing position, posture, etc. Traditionally, users either work with predefined parameter values not optimized for individuals or undergo time-consuming calibration processes. We propose an online Bayesian Optimization (BO)-based method for rapidly determining the user-specific optimal settings of wrist-based pointing. Specifically, we develop a meta-Bayesian optimization (meta-BO) method, differing from traditional human-in-the-loop BO: By incorporating meta-learning of prior optimization data from a user population with BO, meta-BO enables rapid calibration of parameters for new users with a handful of trials. We evaluate our method with two representative and distinct wrist-based interactions: absolute and relative pointing. On a weighted-sum metric that consists of completion time, aiming error, and trajectory quality, meta-BO improves absolute pointing performance by 22.92% and 21.35% compared to BO and manual calibration, and improves relative pointing performance by 25.43% and 13.60%.
doi.org/10.1145/3613904.3642071
We present vARitouch, a back-of-the-finger wearable that can modify the perceived tactile material properties of the uninstrumented world around us: vARitouch can modulate the perceived softness of a rigid object through a vibrotactile compliance illusion. As vARitouch does not cover the fingertip, all-natural tactile properties are preserved. We provide three contributions: (1) We demonstrate the feasibility of the concept through a psychophysics study, showing that virtual compliance can be continuously modulated, and perceived softness can be increased by approximately 30 Shore A levels. (2) A qualitative study indicates the desirability of such a device, showing that a back-of-the-finger haptic device has many attractive qualities. (3) To implement vARitouch, we identify a novel way to measure pressure from the back of the finger by repurposing a pulse oximetry sensor. Based on these contributions, we present the finalized vARitouch system, accompanied by a series of application scenarios.
doi.org/10.1145/3613904.3642828
We propose a novel concept for haptics in which one centralized on-body actuator renders haptic effects on multiple body parts by stimulating the brain, i.e., the source of the nervous system—we call this a haptic source-effector, as opposed to the traditional wearables’ approach of attaching one actuator per body part (end-effectors). We implement our concept via transcranial-magnetic-stimulation (TMS)—a non-invasive technique from neuroscience/medicine in which electromagnetic pulses safely stimulate brain areas. Our approach renders ~15 touch/force-feedback sensations throughout the body (e.g., hands, arms, legs, feet, and jaw—which we found in our first user study), all by stimulating the user’s sensorimotor cortex with a single magnetic coil moved mechanically across the scalp. In our second user study, we probed into participants’ experiences while using our haptic display in VR. Finally, as the first implementation of full-body haptics based on non-invasive brain stimulation, we discuss the roadmap to extend its interactive opportunities.
doi.org/10.1145/3613904.3642483
Tracking fine-grained finger movements with IMUs for continuous 2D-cursor control poses significant challenges due to limited sensing capabilities. Our findings suggest that finger-motion patterns and the inherent structure of joints provide beneficial physical knowledge, which lead us to enhance motion perception accuracy by integrating physical priors into ML models. We propose MouseRing, a novel ring-shaped IMU device that enables continuous finger-sliding on unmodified physical surfaces like a touchpad. A motion dataset was created using infrared cameras, touchpads, and IMUs. We then identified several useful physical constraints, such as joint co-planarity, rigid constraints, and velocity consistency. These principles help refine the finger-tracking predictions from an RNN model. By incorporating touch state detection as a cursor movement switch, we achieved precise cursor control. In a Fitts’ Law study, MouseRing demonstrated input efficiency comparable to touchpads. In real-world applications, MouseRing ensured robust, efficient input and good usability across various surfaces and body postures.
doi.org/10.1145/3613904.3642225