This paper presents TouchpadAnyWear, a novel family of textile-integrated force sensors capable of multi-modal touch input, encompassing micro-gesture detection, two-dimensional (2D) continuous input, and force-sensitive strokes. This thin (<1.5 mm) and conformal device features high spatial resolution sensing and motion artifact tolerance through its unique capacitive sensor architecture. The sensor consists of a knitted textile compressive core, sandwiched by stretchable silver electrodes, and conductive textile shielding layers on both sides. With a high-density sensor pixel array (25/cm2), TouchpadAnyWear can detect touch input locations and sizes with millimeter-scale spatial resolution and a wide range of force inputs (0.05 N to 20 N). The incorporation of miniature polymer domes, referred to as “poly-islands”, onto the knitted textile locally stiffens the sensing areas, thereby reducing motion artifacts during deformation. These poly-islands also provide passive tactile feedback to users, allowing for eyes-free localization of the active sensing pixels. Design choices and sensor performance are evaluated using in-depth mechanical characterization. Demonstrations include an 8-by-8 grid sensor as a miniature high-resolution touchpad and a T-shaped sensor for thumb-to-finger micro-gesture input. User evaluations validate the effectiveness and usability of TouchpadAnyWear in daily interaction contexts, such as tapping, forceful pressing, swiping, 2D cursor control, and 2D stroke-based gestures. This paper further discusses potential applications and explorations for TouchpadAnyWear in wearable smart devices, gaming, and augmented reality devices.

We present a compact broadband linear actuator, Chasm, that renders expressive haptic feedback on wearable and handheld devices. Unlike typical motor-based haptic devices with integrated gearheads, Chasm utilizes a miniature leadscrew coupled to a motor shaft, thereby directly translating the high-speed rotation of the motor to the linear motion of a nut carriage without an additional transmission. Due to this simplicity, Chasm can render low-frequency skin-stretch and high-frequency vibrations, simultaneously and independently. We present the design of the actuator assembly and validate its electromechanical and perceptual performance. We then explore use cases and show design solutions for embedding Chasm in device prototypes. Finally, we report investigations with Chasm in two VR embodiments, i.e., in a headgear band to induce locomotion cues and in a handheld pointer to enhance dynamic manual interactions. Our explorations show wide use for Chasm in enhancing user interactions and experience in virtual and augmented settings.