Survey on Energy Harvesting for Biomedical Devices: Applications, Challenges and Future Prospects for African Countries

Abstract

Self-powered biomedical devices, which are the new vision of Internet Of Things (IOT) healthcare, are facing many technical and application challenges. Many research works have reported biomedical devices and self-powered applications for healthcare, along with various strategies to improve the monitoring time of self-powered devices or to eliminate the dependence on electrochemical batteries. However, none of these works have especially assessed the development and application of healthcare devices in an African context. This article provides a comprehensive review of self-powered devices in the biomedical research field, introduces their applications for healthcare, evaluates their status in Africa by providing a thorough review of existing biomedical device initiatives and available financial and scientific cooperation institutions in Africa for the biomedical research field, and highlights general challenges for implementing self-powered biomedical devices and particular challenges related to developing countries. The future perspectives of the aforementioned research field are provided, as well as an architecture for improving this research field in developing countries.

Keywords: Africa; biomedical research; biomedical research funding; energy harvesting; self-powered biomedical devices.

Figure 1

Systematic review protocol followed for answering the research questions (RQs).

Figure 2

Illustration of the potential applications of implanted PV devices for powering implantable electronics such as pacemakers (a). The feasibility of the study is shown by lighting LEDs with power from integrated PV devices under human hand dorsum skin (b). Optical image of IPV device bent on a human arm (c), image of fixed human skin covering IPV cells (d) [25]. In vivo self-powered cardiac sensor for estimating blood pressure and velocity of blood flow (e) [26]. Self-tuning inductive powering system for biomedical implants (f) [27]. Self-powered cardiac pacemaker with a piezoelectric polymer nanogenerator implant (g) [28]. Implantable and self-powered blood pressure monitoring based on a piezoelectric thin film (h) [29]. Schematic diagram of a self-powered wireless transmission system based on an implanted triboelectric nanogenerator (iWT: implantable Wireless Transmitter; PMU: Power Management Unit) (i) [30]. A battery-less implantable glucose sensor based on electrical impedance spectroscopy; sensor implantation on the pig for experimentation (j) [31]. Biocompatible battery for medical implant charged via ultrasound (k) [32]. Self-powered deep brain stimulation via a flexible PIMNT energy harvester (l) [33]. Self-powered implantable electrical stimulator for osteoblast proliferation and differentiation (m) [34]. An implantable biomechanical energy harvester for animal monitoring devices (n) [35]. Reproduced with permission from [25,26,27,28,29,30,31,32,33,34,35].

Figure 3

Schematic illustration of the potential applications of non-invasive, wearable, self-powered devices. Non-invasive glucose meters (a–e) [36,37,38,39,40]. Wireless, battery-free wearable sweat sensor powered by human motion, along with the schematic illustrating human motion energy harvesting, signal processing, microfluidic-based sweat biosensing, and Bluetooth-based wireless data transmission to a mobile user interface for real-time health status tracking (f) [41]. Wearable applications of body-integrated self-powered systems (BISSs) (g) [42]. Behavioral and environmental sensing and intervention (BESI), which combines environmental sensors placed around the homes of dementia patients for detecting the early stage of agitation (h) [43]. Schematic representation of glucose level detection in human sweet (i) [44]. Wearable circuits sintered at room temperature directly on the skin surface for health monitoring (j) [45]. Diagram of flexible, wearable, self-powered electronics based on a body-integrated self-powered system (BISS) (k) [42]. Technology-Enabled Medical Precision Observation (TEMPO): a wristwatch-sized device that can be worn on various parts of the body for monitoring user’s agitation during motion and detect early cerebral palsy, Parkinson’s disease and multiple sclerosis (l) [43]. The device was developed by the University of Virginia. Stretchable micro-supercapacitors which harvest energy from human breathing and motion for self-powering wearable devices (m) [46]. Reproduced with permission from [36,37,38,39,40,41,42,43,44,45,46].

Figure 4

Examples of miniaturized biomedical devices and self-powered implants. Self-rechargeable cardiac pacemaker (a) [72]; troboelectric active sensor (b) [72,73]; retinal prosthesis system, a variable external unit with camera attached to it (c) [74]; self-powered vagus nerve stimulator device for effective weight control (d) [75]; an ultrasonic energy harvester in use in a cochlear hearing aid (e) [76]; energy harvesting from radio waves for powering wearable devices (f) [77]; self-powered metamaterial implant for the detection of bone healing progress (g) [13]; self-powered electrostatic adsorption face mask based on a triboelectric nanogenerator (h) [78]; self-powered implantable device for stimulating fast bone healing, which then disappears without a trace (i); self-powered smart watch and wristband enabled by an embedded generator (j) [79]. Reproduced with permission from [13,72,73,74,75,76,77,78,79].

Figure 5

Future directions of self-powered biomedical devices in Africa: restoring the sense of touch to an injured finger (a) [83], intravenous drug delivery (b) [84], a self-powered GPS tracker for cattle (c) [85], and an e-health watch for temperature and heartbeat rate monitoring (d) [86].

Figure 6

Architecture of scientific cooperation and funding in biomedical research suitable for low-and middle-income countries.