Passive and Self-Powered Autonomous Sensors for Remote Measurements

Autonomous sensors play a very important role in the environmental, structural, and medical fields. The use of this kind of systems can be expanded for several applications, for example in implantable devices inside the human body where it is impossible to use wires. Furthermore, they enable measurements in harsh or hermetic environments, such as under extreme heat, cold, humidity or corrosive conditions. The use of batteries as a power supply for these devices represents one solution, but the size, and sometimes the cost and unwanted maintenance burdens of replacement are important drawbacks. In this paper passive and self-powered autonomous sensors for harsh or hermetical environments without batteries are discussed. Their general architectures are presented. Sensing strategies, communication techniques and power management are analyzed. Then, general building blocks of an autonomous sensor are presented and the design guidelines that such a system must follow are given. Furthermore, this paper reports different proposed applications of autonomous sensors applied in harsh or hermetic environments: two examples of passive autonomous sensors that use telemetric communication are proposed, the first one for humidity measurements and the second for high temperatures. Other examples of self-powered autonomous sensors that use a power harvesting system from electromagnetic fields are proposed for temperature measurements and for airflow speeds

The Development of an in Vivo Spinal Fusion Monitor Using Microelectromechanical (Mems) Technology to Create Implantable Microsensors

Surgical fusion of the spine is a conventional approach, and often last alternative, to the correction of a degenerative painful spinal segment. The procedure involves the surgical removal of the intervertebral disc at the problematic site, and the placement of a bone graft that is commonly harvested from the patients iliac crest and placed within the discectomized space. The surrounding bone is expected to incorporate and remodel into the bone graft to eventually provide an immobilized site. Spinal instrumentation often accompanies the bone graft to provide further immobility to the targeted site, thus augmenting the fusion process. However, the status of a fusion and the incorporation of bone across a destabilized spinal segment are often difficult for the surgeon to assess. Radiographic methods provide static views of the fusion site that possess excessive limitations. The radiographic image cannot provide the surgeon with information regarding fusion integrity when the patient is mobile and the spine is exposed to multiple motions. Fortunately, technological advances utilizing microelectromechanical system technology (MEMS) have provided insight into the development of miniature devices that exhibit high resolution, electronic accuracy, miniature sizing, and have the capacity to monitor long-term, real-time in vivo pressures and forces for a variety of situations. However, numerous challenges exist with the utilization of MEMS devices for in vivo applications.This work investigated the feasibility of utilizing implantable microsensors to monitor the pressure and force patterns of bone incorporation and healing of a spine fusion in vivo. The knowledge obtained from this series of feasibility tests using commercially available transducers to monitor pressures and forces, will be applied towards the development of miniature sensors that utilize MEMS technology to monitor real-time, long-term spine fusion in living subjects. The packaging, radiographic, and sterilization characteristics of MEMS sensors were eva

The Development of an in Vivo Spinal Fusion Monitor Using Microelectromechanical (Mems) Technology to Create Implantable Microsensors

Surgical fusion of the spine is a conventional approach, and often last alternative, to the correction of a degenerative painful spinal segment. The procedure involves the surgical removal of the intervertebral disc at the problematic site, and the placement of a bone graft that is commonly harvested from the patients iliac crest and placed within the discectomized space. The surrounding bone is expected to incorporate and remodel into the bone graft to eventually provide an immobilized site. Spinal instrumentation often accompanies the bone graft to provide further immobility to the targeted site, thus augmenting the fusion process. However, the status of a fusion and the incorporation of bone across a destabilized spinal segment are often difficult for the surgeon to assess. Radiographic methods provide static views of the fusion site that possess excessive limitations. The radiographic image cannot provide the surgeon with information regarding fusion integrity when the patient is mobile and the spine is exposed to multiple motions. Fortunately, technological advances utilizing microelectromechanical system technology (MEMS) have provided insight into the development of miniature devices that exhibit high resolution, electronic accuracy, miniature sizing, and have the capacity to monitor long-term, real-time in vivo pressures and forces for a variety of situations. However, numerous challenges exist with the utilization of MEMS devices for in vivo applications.This work investigated the feasibility of utilizing implantable microsensors to monitor the pressure and force patterns of bone incorporation and healing of a spine fusion in vivo. The knowledge obtained from this series of feasibility tests using commercially available transducers to monitor pressures and forces, will be applied towards the development of miniature sensors that utilize MEMS technology to monitor real-time, long-term spine fusion in living subjects. The packaging, radiographic, and sterilization characteristics of MEMS sensors were eva

MCU-Based Multi Parameter Patient Monitor

The patient monitoring system presented in this research is able to detects, process, displays, four essential clinical parameters; body temperature, blood pressure, Electro Cardiogram (ECG) interpretation, and heart rate, to inform the patient and the physician in short time, using an advanced low cost design, low power consumption and high accuracy methodologies. The proposed device intended to be placed in the intensive care unit (ICU), and the produced signal will be processed by microcontroller (AVR) and then displayed results in graphical LCD (GLCD)

Design of a Customized multipurpose nano-enabled implantable system for in-vivo theranostics

The first part of this paper reviews the current development and key issues on implantable multi-sensor devices for in vivo theranostics. Afterwards, the authors propose an innovative biomedical multisensory system for in vivo biomarker monitoring that could be suitable for customized theranostics applications. At this point, findings suggest that cross-cutting Key Enabling Technologies (KETs) could improve the overall performance of the system given that the convergence of technologies in nanotechnology, biotechnology, micro&nanoelectronics and advanced materials permit the development of new medical devices of small dimensions, using biocompatible materials, and embedding reliable and targeted biosensors, high speed data communication, and even energy autonomy. Therefore, this article deals with new research and market challenges of implantable sensor devices, from the point of view of the pervasive system, and time-to-market. The remote clinical monitoring approach introduced in this paper could be based on an array of biosensors to extract information from the patient. A key contribution of the authors is that the general architecture introduced in this paper would require minor modifications for the final customized bio-implantable medical device

The Development of an in Vivo Spinal Fusion Monitor Using Microelectromechanical (Mems) Technology to Create Implantable Microsensors

Surgical fusion of the spine is a conventional approach, and often last alternative, to the correction of a degenerative painful spinal segment. The procedure involves the surgical removal of the intervertebral disc at the problematic site, and the placement of a bone graft that is commonly harvested from the patients iliac crest and placed within the discectomized space. The surrounding bone is expected to incorporate and remodel into the bone graft to eventually provide an immobilized site. Spinal instrumentation often accompanies the bone graft to provide further immobility to the targeted site, thus augmenting the fusion process. However, the status of a fusion and the incorporation of bone across a destabilized spinal segment are often difficult for the surgeon to assess. Radiographic methods provide static views of the fusion site that possess excessive limitations. The radiographic image cannot provide the surgeon with information regarding fusion integrity when the patient is mobile and the spine is exposed to multiple motions. Fortunately, technological advances utilizing microelectromechanical system technology (MEMS) have provided insight into the development of miniature devices that exhibit high resolution, electronic accuracy, miniature sizing, and have the capacity to monitor long-term, real-time in vivo pressures and forces for a variety of situations. However, numerous challenges exist with the utilization of MEMS devices for in vivo applications.This work investigated the feasibility of utilizing implantable microsensors to monitor the pressure and force patterns of bone incorporation and healing of a spine fusion in vivo. The knowledge obtained from this series of feasibility tests using commercially available transducers to monitor pressures and forces, will be applied towards the development of miniature sensors that utilize MEMS technology to monitor real-time, long-term spine fusion in living subjects. The packaging, radiographic, and sterilization characteristics of MEMS sensors were eva

Modern Telemetry

Telemetry is based on knowledge of various disciplines like Electronics, Measurement, Control and Communication along with their combination. This fact leads to a need of studying and understanding of these principles before the usage of Telemetry on selected problem solving. Spending time is however many times returned in form of obtained data or knowledge which telemetry system can provide. Usage of telemetry can be found in many areas from military through biomedical to real medical applications. Modern way to create a wireless sensors remotely connected to central system with artificial intelligence provide many new, sometimes unusual ways to get a knowledge about remote objects behaviour. This book is intended to present some new up to date accesses to telemetry problems solving by use of new sensors conceptions, new wireless transfer or communication techniques, data collection or processing techniques as well as several real use case scenarios describing model examples. Most of book chapters deals with many real cases of telemetry issues which can be used as a cookbooks for your own telemetry related problems

Evaluation of the performance of a wireless magnetoelastic pH-sensor in rumen environment

Sub-acute rumen acidosis (SARA) is a problem with major economic importance in dairy production. The definition of SARA is a low pH (< 5.3-5.5) in the rumen during several hours in the day. Due to lack of other confirmatory clinical sign, SARA is diagnosed by measuring pH of the ruminal fluid. According to the definition continuous measurement of rumen pH is needed to diagnose SARA but until now methods for that purpose only exist for fistulated animals. In recent years, diagnostic tools in the biological field based on wireless telemetric technology have been developed. A magnetoelastic sensor which can swell and shrink in response to different pH levels was evaluated in this project. The sensor was tested in water, phosphate buffer, VOS buffer, McDougall’s buffer, rumen liquid as well and in vivo in a cannulated cow. This sensor was prepared by casting layers of polymer on a magnetic ribbon, set up this ribbon in a plastic frame and then wrap ping it with magnetic paper. A box like wooden structure was used in case of in vitro which can conserve heat and provide a continuous rumen temperature. The prepared sensor upon application of a magnetic field produced mechanical vibration and thus production of a magnetic flux which can be received by a pickup coil. The measurement system consisted of the magnetoelastic sensor, a coil for excitation and pick up of the sensors resonance frequency, a control unit and a computer for signal processing and evaluation. The signals received from the sensor seemed to be affected by the use of an electric stirrer and also by gas bubbles produced during mixing of acids in buffer. However, this sensor was able to provide specific and repeatable signals in different ionic concentration. The changes in pH level of the rumen liquid were detected within a wide range of pH (from 3 to 10) whereas for the cow a more narrow range in pH (5 to 7) is required. Due to the too wide range of pH the change in frequency was difficult to calibrate against pH. Future work should be carried out with the aim to find a more appropriate polymer (e.g. peptide based) to increase the signal within the rumen pH range