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April 2021 saw a widespread outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Osaka, Japan. We encountered the case of a 52-year-old man who had Guillain–Barré syndrome associated with coronavirus disease 2019 (COVID-19). After the relief of the respiratory symptoms owing to COVID-19, the patient experienced muscle weakness, which spread from his fingers to his extremities, and was unable to walk. Further examinations revealed mild protein elevation in the cerebrospinal fluid. In addition, nerve conduction studies showed demyelinating polyneuropathy, leading to the diagnosis of Guillain–Barré syndrome. After the administration of intravenous immunoglobulin and intravenous methylprednisolone, his symptoms drastically improved, and he was able to walk unaided 21 days after the onset of symptoms. On day 40, the patient was discharged with minimal muscle fatigue. Because Guillain–Barré syndrome associated with COVID-19 is expected to have a good prognosis, early diagnosis and treatment are important. Therefore, Guillain–Barré syndrome should be considered as a possible factor for muscle weakness during and after COVID-19 treatment.

Tactile sensing is desirable for skillful object handling in soft robotics applications. Real‐time measurement and identification of dynamic shear forces are crucial for slip detection and object interaction. This study proposes a soft sensor with a closed‐loop feedback system for dynamic shear force detection to address object slippage in a soft robotic gripper. The sensor is made of a ferroelectric polymer with nanocarbon materials because of the resulting improved crystallinity and good sensitivity. The sensor shows high performance and high‐speed response for detecting dynamic shear forces when fragile objects (e.g., vegetables) slip from the soft gripper. The artificial cutaneous sensor shows high sensitivity for grasping such objects with the gripper. Furthermore, the feedback system provides a control system for operations and avoids the need for training for various tasks, thus demonstrating the potential of the proposed system for novel soft robotics applications such as biomimetic electronic skin.

Tactile sensing, particularly the detection of object slippage, is required for skillful object handling by robotic grippers. The real-time measurement and identification of the dynamic shear forces that result from slippage events are crucial for slip detection and effective object interaction. In this study, a ferroelectric polymer-based printed soft sensor for object slippage detection was developed and fabricated by screen printing. The proposed sensor demonstrated a sensitivity of 8.2 μC·cm−2 and was responsive to shear forces applied in both the parallel and perpendicular directions. An amplifier circuit, based on a printed organic thin-film transistor, was applied and achieved a high sensitivity of 0.1 cm2/V·s. Therefore, this study experimentally demonstrates the effectiveness of the proposed printable high-sensitivity tactile sensor, which could serve as part of a wearable robotic e-skin. The sensor could facilitate the production of a system to detect and prevent the slippage of objects from robotic grippers.