Abstract: In clinical work, many soft medical pipelines are located deep within the body, resulting in a lack of feedback regarding bending or folding conditions, which presents significant challenges for medical staff. To solve the problem, this study innovatively designs a flexible bending sensor, which can be attached to the medical pipelines and monitor the bending conditions. Based on a flexible substrate with secondary microstructures copied from champagne rose petals, the interdigital electrodes are designed to enhance the sensitivity of the sensor due to the amplifying effect. A high sensitivity of 2.209%^?1in a bending strain range of 8.9%, and a stable repeatability for over 6000 cycles under 1.8% bending strain are achieved by the sensor. By integrating the bending sensor, here, the nasogastric tube, femoral vein catheter, and tracheal intubation are used to demonstrate the sensing performance. Additionally, during the measurement, the sensing signals are processed and transformed to the bending angles simultaneously, enabling the direct visualization of the bending conditions of the pipelines. This work proposes innovative applications for bending sensors in medical technology and establishes a foundation for further research on flexible bending sensors.

Key words: Bionic design')">Bionic design, Microstructures, Bending sensor, Medical pipeline recognition