A Large-Area Broadband Multimodal Dual-Resonant Haptic Device for Bidirectional Telerobotic and Augmented Interactions.

Bidirectional haptic systems demand interfaces that combine sensing and actuation, enabling concurrent detection of tactile inputs and delivery of perceptually rich feedback across a broad frequency spectrum. However, most existing haptic technologies remain limited to simple tactile sensing or narrowband feedback, struggling to resolve continuous motions and simultaneous sensory cues required for naturalistic human-machine interaction (HMI). These limitations fundamentally constrain the fidelity and expressiveness of tactile communication, preventing current human-machine interfaces from reproducing the broadband of sensations perceived by human skin. Here, we present a large-area bidirectional human-machine interface (HMI) that utilizes a unified haptic dual-resonant actuator (UHDRA) capable of simultaneously implementing electrostatic-based multimodal tactile sensing and actuation. The system provides spatially uniform tactile stimulation over a broad frequency range of 20-250 Hz while simultaneously enabling real-time detection without interference from actuator-induced vibration. Leveraging the actuator's intrinsic structural stiffness, the interface maintains stable vibration amplitudes into the gentle-touch regime (≈2 N) while selectively modulating frequency, allowing clear discrimination of diverse tactile stimuli without perceptual discontinuity. Building on this decoupled bidirectional interaction capability, the proposed approach offers transformative potential for next-generation applications such as bidirectional telerobotic and augmented interactions.