Soft robotics are characterized by their high deformability, mechanical robustness, and inherent resistance to damage. These unique properties present exciting new opportunities to enhance both emerging and existing fields such as healthcare, manufacturing, and exploration. However, to function effectively in unstructured environments, these technologies must withstand the same real-world conditions to which human skin and other soft biological materials are typically subjected. Here, we present a novel soft material architecture designed for active detection of material damage and autonomous repair in soft robotic actuators. By integrating liquid metal (LM) microdroplets within a silicone elastomer, the system can detect and localize damage through the formation of conductive pathways that arise from extreme pressure (> 1 MPa) or puncture events. These newly formed conductive networks function as in situ Joule heating elements, facilitating the reprocessing and healing of the material. The architecture allows for the reconfiguration of the newly formed electrical network using controlled electrical and thermal mechanisms to restore functionality. The entire process from damage detection to repair and reconfiguration occurs without any manual intervention or external mechanisms to facilitate healing. This innovative approach not only enhances the resilience and performance of soft materials but also supports a wide range of applications in soft robotics and wearable technologies, where adaptive and autonomous systems are crucial for operation in dynamic and unpredictable environments.

This paper presents the design of a fully flexible temperature sensor for wearable applications. The sensor is implemented using the newly available flexible integrated electronic circuit (Flex-IC) technology from Pragmatic Semiconductor [1]. To address the design challenges due to the limited set of thin film components available in this non-CMOS technology, a counter-based time-to-digital conversion (TDC) technique has been developed, where the pulses provided by a temperature-dependent ring oscillator are gated and counted by a temperature-independent delay cell. The operation of the delay cell relies on the temperature coefficient cancellation of resistive components by a cross-coupled pair. A tunable calibration mechanism is also incorporated in the design to handle the process corners in a temperature range of 32 °C - 42 °C suitable for biological sensing. The presented sensor design exhibits a low time-jitter induced measurement error, with a 0.81 % probability of toggling the least significant bit (LSB) per sample, maintaining 0.1 °C precision and a zero-error range of 6.8 °C, while dissipating a power of 2.5 mW with an acquisition time of 3 ms. The chip layout measures 3.0 mm×3.0 mm with a die thickness of 30 μm. Compared to existing rigid and hybrid systems, the Flex-IC technology opens up opportunities for advancing conformal electronics, particularly for applications requiring continuous monitoring on dynamic body surfaces.

Electronic skins and tactile sensors can provide the sense of touch to robotic manipulators. These sensing modalities complement existing long range optical sensors and can provide detailed information before and after contact. However, integration with existing systems can be challenging due to size constraints, the interface geometry, and restrictions of external wiring used to interface with the sensor. Here, we introduce a low-profile, wireless electronic skin for direct integration with existing robotic manipulators. The flexible electronic skin combines pressure, optical proximity sensing, and a micro-LIDAR device in a small, low profile package. Each of the sensors are characterized individually and the system is demonstrated on Robonaut 2, an anthropomorphic robot designed to work in environments designed for humans. We demonstrate the sensor can be used for contact sensing, mapping of local unknown environments, and to provide medical monitoring during an emergency in a remote area.

Wearables have emerged as an increasingly promising interactive platform, imbuing the human body with always-available computational capabilities. This unlocks a wide range of applications, including discreet information access, health monitoring, fitness, and fashion. However, unlike previous platforms, wearable electronics require structural conformity, must be comfortable for the wearer, and should be soft, elastic, and aesthetically appealing. We envision a future where electronics can be temporarily attached to the body (like bandages or party masks), but in functional and aesthetically pleasing ways. Towards this vision, we introduce ElectroDermis, a fabrication approach that simplifies the creation of highly-functional and stretchable wearable electronics that are conformal and fully untethered by discretizing rigid circuit boards into individual components. These individual components are wired together using stretchable electrical wiring and assembled on a spandex blend fabric, to provide high functionality in a robust form-factor that is reusable. We describe our system in detail- including our fabrication parameters and its operational limits-which we hope researchers and practitioners can leverage. We describe a series of example applications that illustrate the feasibility and utility of our system. Overall, we believe ElectroDermis offers a complementary approach to wearable electronics-one that places value on the notion of impermanence (i.e., unlike tattoos and implants), better conforming to the dynamic nature of the human body.