Acoustic transmission, or sound, can effectively communicate information over distances through various media. We focus on generating acoustic transmission using pneumatically driven resonators for wireless tactile sensing without the need for any electronics at the end-effector or contact point. We explore the relationship between emitted frequency and the geometry of the resonance chamber. When a normal compressive force is applied to the end cap, the compliant resonant cavity deforms, leading to an increase in frequency measurable by an external microphone. Prior work uses tube resonators with fipple attachments. In the present work, we study whether a different smaller audible cylindrical resonator with air blown across the entryway can be utilized instead. We test the utility of the Helmholtz resonator model in predicting the experimental frequency response. Resonance is often modeled for rigid cavities, presenting unique challenges in predicting resonance for the design of soft resonating taxels.

We present SunBot, a robotic system for the study and implementation of fish-inspired tearing manipulations. Various fish species–such as the sunburst butterflyfish-feed on prey fixed to substrates, a maneuver previously not demonstrated by robotic fish which typically specialize for open water swimming and surveillance. Biological studies indicate that a dynamic “head flick” behavior may play a role in tearing off soft prey during such feeding. In this work, we study whether the robotic tail is an effective means to generate such head motions for ungrounded tearing manipulations in water. We describe the function of SunBot and compare the forces that it applies to a fixed prey in the lab while varying tail speeds and ranges of motion. A simplified dynamic template model for the tail-driven head flick maneuver matches peak force magnitudes from experiments, indicating that inertial effects of the fish's body play a substantial role. Finally, we demonstrate a tearing scenario and evaluate a free-swimming trial of SunBot – this is important to show that the actuator that enables swimming also provides the new dual purpose of forceful tearing manipulation.

We present a novel robot end-effector for gripping and haptic exploration. Tactile sensing through suction flow monitoring is achieved with a new suction cup design that contains multiple chambers for air flow. Each chamber connects with its own remote pressure transducer, which enables both absolute and differential pressure measures between chambers. By changing the overall vacuum applied to this smart suction cup, it can perform different functions such as gentle haptic exploration (low pressure) and monitoring breaks in the seal during strong astrictive gripping (high pressure). Haptic exploration of surfaces through sliding and palpation can guide the selection of suction grasp locations and help to identify the local surface geometry. During suction gripping, a trained LSTM network can localize breaks in the suction seal between four quadrants with up to 97% accuracy and detects breaks in the suction seal early enough to avoid total grasp failure.