Wearable Exoskeleton System for Energy Harvesting and Angle Sensing Based on a Piezoelectric Cantilever Generator Array

Abstract

Wearable exoskeletons are developing rapidly due to their superiority in improving human ability and efficiency. The construction of a multifunctional exoskeleton system relies on an efficient continuous energy supply and various high-performance sensors. Here, a magnetic-driven piezoelectric cantilever generator (MPCG) array is designed for energy harvesting and angle sensing of joint motions. Combining theoretical derivation and experimental characterization, it is found that the nonlinear magnetic force acting on the cantilever structure will cause the phenomenon of frequency upconversion, which greatly improves the output of the MPCG. The experiment successfully proves the feasibility of using the MPCG array as an energy-harvesting module to collect energy from human joint motions and power an RH/temp sensor. Furthermore, the MPCG array can also be used to sense the rotation angle and angular velocity. By integrating with a wireless data acquisition and transmission module and supporting software, a wearable joint rehabilitation monitoring and assessment system is built, which can measure the activities of the joint in real time and evaluate the flexion degree. The demonstrated wearable exoskeleton system for joint motion energy harvesting and joint angle sensing is of great value for the construction of a multifunctional exoskeleton system and wearable smart rehabilitation equipment.

Electric Power Generated from Magnetic Nanofluid Droplets Sliding upon Superslippery Surfaces

“…The current value could exceed 6 μA, which surpasses current values generated by previous liquid-based generators ,,, based on the triboelectric principle. Moreover, the current is also higher than that of other triboelectric − and piezoelectric devices, − primarily due to the low internal resistance of the magnetoelectric devices in this study. When compared to previously prepared magnetoelectric devices, , our fabricated devices also demonstrate an advantage in terms of output current, as shown in Table .…”

Recent Progress in Application‐Oriented Self‐Powered Microelectronics

“…It plays a huge role in the health monitoring of the elderly, medical care, and sports guidance. [392] Luo et al [380] proposed a wearable brace for rehabilitation assessment of patients with total knee arthritis, as shown in Figure 9b. The bracket is composed of a force transducer for isometric muscle strength measurement and a TENG angle sensor of the knee joint.…”

“…It plays a huge role in the health monitoring of the elderly, medical care, and sports guidance. [ 392 ] Luo et al. [ 380 ] proposed a wearable brace for rehabilitation assessment of patients with total knee arthritis, as shown in Figure 9b.…”

A Self‐Powered and Self‐Sensing Lower‐Limb System for Smart Healthcare

“…[61,62] In this case, self-powered sensors with a rigid structure for accurate sensing and easy integration with exoskeleton devices exhibit great advantages in lower-limb motion monitoring. [63,64] In recent years, many lowerlimb wearable devices, especially knee devices, have been developed for energy harvesting and motion sensing. Figure 1 presents the technical evolution of knee wearable devices.…”