Polymer optical fiber and fiber Bragg grating sensors for biomedical engineering Applications: A comprehensive review

Polymer or Plastic Optical Fiber sensors (POFs) and Fiber Bragg Grating sensors (FBGs) have gained increasing popularity in biomedical engineering (BME) applications over the past decades due to their unique properties such as compact size, lightweight, wide dynamic range, biocompatibility, electromagnetic and radio frequency interference immunity, high strain sensitivity, and multiplexing capabilities. The POF sensor flexibility, low Young's modulus (sensitivity to mechanical changes), higher elastic limits, and higher impact resistance make it suitable for instrumentation requirements in medical devices and biological analysis and measurements. Medical applications for POFs and FBGs have been demonstrated by developing instruments, gait assistance devices, wearables, and biosensors. This paper presents an ambitious review of the current state of the art of POF and FBG-based measuring techniques based on optical multicore fibers (MCF) or multiple optical single-core fibers with embedded FOS sensors. It comprehensively analyses how various sensor variants have been used in medical, healthcare, and remote sensing applications. The review comprises a range of aspects, which include: (I) research methodology; (II) an overview of POF and FBG sensing technology; (III) applications of POFs and FBGs in BME applications; (IV) current state and future trends of POFs and FBGs in the field of BME. The BME applications discussed include applications of POFs and FBGs in; (1) physiological parameter monitoring; (2) biomechanics; (3) foot plantar pressure assessment; (4) gait assistance wearable devices and rehabilitation robotics; (5) joint angle measurement and human movement assessment; (6) health diagnosis; (7) robotic medical microsurgery; and (8) temperature monitoring during thermal ablation treatment.