scispace - formally typeset
Search or ask a question
Proceedings ArticleDOI

A novel sensor for wrist based optical heart rate monitor

TL;DR: A novel 590 nm (yellow-orange) wavelength based optical system is tailored suitably to maximize the signal quality acquired and holds an advantage over its shorter counterpart when subjected to varied skin pigmentation levels.
Abstract: The growing demands of continuous healthcare and hence physiological monitoring necessitates a system with high reliability and accuracy. Wearable used for continuous cardiological parameter estimation from wrist use reflective photoplethysmography technique that has certain limitations which are imperative. One such constraint is skin pigmentation of the subject. In the present work a sensor module design is proposed addressing to the anomalies due to optical properties of skin. A novel 590 nm (yellow-orange) wavelength based optical system is tailored suitably to maximize the signal quality acquired. The proposed setup is validated on a conglomeration of subjects in terms of age, gender and skin tone. A generous agreement between coherent measures for signal quality shows that the proposed wavelength holds an advantage over its shorter counterpart when subjected to varied skin pigmentation levels. A maximum improvement factor of 71 is observed in case of perfusion index, 31 for pulsatile strength and 3 for SNR. The details of sensor design, experimental setup, validation protocol, observations and inferences drawn from the study are presented.
Citations
More filters
Journal ArticleDOI
25 May 2018-Sensors
TL;DR: A taxonomy of sensors, functionalities, and methods used in non-invasive wrist-wearable devices was assembled and the main features of commercial wrist- wearable devices are presented.
Abstract: Wearable devices have recently received considerable interest due to their great promise for a plethora of applications. Increased research efforts are oriented towards a non-invasive monitoring of human health as well as activity parameters. A wide range of wearable sensors are being developed for real-time non-invasive monitoring. This paper provides a comprehensive review of sensors used in wrist-wearable devices, methods used for the visualization of parameters measured as well as methods used for intelligent analysis of data obtained from wrist-wearable devices. In line with this, the main features of commercial wrist-wearable devices are presented. As a result of this review, a taxonomy of sensors, functionalities, and methods used in non-invasive wrist-wearable devices was assembled.

180 citations


Cites background from "A novel sensor for wrist based opti..."

  • ...[77] proposed a sensor module design addressing anomalies due to the optical properties of skin....

    [...]

Journal ArticleDOI
TL;DR: In this article, a comprehensive review of the literature that aims to summarize these noise sources for future photoplethysmography (PPG) device development for use in health monitoring is presented.

77 citations

Journal ArticleDOI
TL;DR: Wearable devices with embedded photoplethysmography (PPG) sensors enable continuous monitoring of cardiovascular activity, allowing for the detection cardiovascular problems, such as arrhythmias, unless methods can be identified to improve low quality signal segments.
Abstract: Objective Wearable devices with embedded photoplethysmography (PPG) sensors enable continuous monitoring of cardiovascular activity, allowing for the detection cardiovascular problems, such as arrhythmias. However, the quality of wrist-based PPG is highly variable, and is subject to artifacts from motion and other interferences. The goal of this paper is to evaluate the signal quality obtained from wrist-based PPG when used in an ambulatory setting. Approach Ambulatory data were collected over a 24 h period for 10 elderly, and 16 non-elderly participants. Visual assessment is used as the gold standard for PPG signal quality, with inter-rater agreement evaluated using Fleiss' Kappa. With this gold standard, 5 classifiers were evaluated using a modified 13-fold cross-validation approach. Main results A Random Forest quality classification algorithm showed the best performance, with an accuracy of 74.5%, and was then used to evaluate 24 h long ambulatory wrist-based PPG measurements. Significance In general, data quality was high at night, and low during the day. Our results suggest wrist-based PPG may be best for continuous cardiovascular monitoring applications during the night, but less useful during the day unless methods can be identified to improve low quality signal segments.

23 citations


Cites methods from "A novel sensor for wrist based opti..."

  • ...[10] Other researchers have proposed methods using different wavelengths of light, such as the yellow-orange spectrum [11]....

    [...]

Proceedings ArticleDOI
14 May 2018
TL;DR: Early results show that an off the shelf system targeted for residential security and home automation applications based on low-cost sensors supported with automated analysis and classification has the potential to be used to assist caregivers and dementia patients.
Abstract: The measurement and detection of overnight wandering is a significant issue for dementia patients and their caregivers such as a spouse The wandering places the patient at risk of injury or even death if they fall or leave their residence without being detected While it also causes stress and reduced sleep for the caregiver as they try to remain alert to the actions of their partner This paper presents initial data for the first participant from an ongoing study of dementia patients where a wander detection and diversion system based on low-cost commercial sensors has been deployed into the residence The paper shows that over a 3-week period, the analysis and classification of the sensor data is able to measure the behavior of the patient In this period, the patient only used the washroom overnight and did not wander into other parts of the residence These early results show that an off the shelf system targeted for residential security and home automation applications based on low-cost sensors supported with automated analysis and classification has the potential to be used to assist caregivers and dementia patients

22 citations


Cites methods from "A novel sensor for wrist based opti..."

  • ...Alternative methods of measuring cognitive decline through EEG/ERP based tests have been presented [18] along with sensor systems to provide ongoing monitoring of vital signs [19]....

    [...]

References
More filters
Proceedings ArticleDOI
05 Nov 2015
TL;DR: HRV analysis was applied on beat-to-beat intervals obtained from ECG and PPG in 19 healthy male subjects and the results showed that the smallest error happens in SDNN and SD2 with relative error of 2.46% and 2%.
Abstract: Heart rate variability (HRV) has become a useful tool in analysis of cardiovascular system in both research and clinical fields. HRV has been also used in other applications such as stress level estimation in wearable devices. HRV is normally obtained from ECG as the time interval of two successive R waves. Recently PPG has been proposed as an alternative for ECG in HRV analysis to overcome some difficulties in measurement of ECG. In addition, PPG-HRV is also used in some commercial devices such as modern optical wrist-worn heart rate monitors. However, some researches have shown that PPG is not a surrogate for heart rate variability analysis. In this work, HRV analysis was applied on beat-to-beat intervals obtained from ECG and PPG in 19 healthy male subjects. Some important HRV parameters were calculated from PPG-HRV and ECG-HRV. Maximum of PPG and its second derivative were considered as two methods for obtaining the beat-to-beat signals from PPG and the results were compared with those achieved from ECG-HRV. Our results show that the smallest error happens in SDNN and SD2 with relative error of 2.46% and 2%, respectively. The most affected parameter is pNN50 with relative error of 29.89%. In addition, in our trial, using the maximum of PPG gave better results than its second derivative.

89 citations


"A novel sensor for wrist based opti..." refers background in this paper

  • ...Continuous and accurate heart rate monitoring facilitates determination of heart rate variability indices [1] which are indicative of stress [2] and other cardio-logical disorders....

    [...]

Proceedings ArticleDOI
28 Dec 2015
TL;DR: This work presents an approach that is based on photoplethysmographic (PPG) signals which are measured with two wrist-type pulse oximeters that suppresses the motion artifacts by adaptively estimating the transfer functions of each of the three-axis acceleration signals that produce the artifacts in the PPG signals.
Abstract: Accurate and reliable estimation of the heart rate using wear able devices, especially during physical exercise, must deal with noisy signals that contain motion artifacts. We present an approach that is based on photoplethysmographic (PPG) signals which are measured with two wrist-type pulse oximeters. The heart rate is related to intensity changes of the reflected light. Our proposed method suppresses the motion artifacts by adaptively estimating the transfer functions of each of the three-axis acceleration signals that produce the artifacts in the PPG signals. We combined the output of the six adaptive filters into a single enhanced time-frequency domain signal based on which we track the heart rate with a high ac curacy. Our approach is real-time capable, computationally efficient and real data results for a benchmark data set illustrate the superior performance compared to a recently pro posed approach.

66 citations


"A novel sensor for wrist based opti..." refers methods in this paper

  • ...Reflectance based PPG is a widely accepted technique used for measurements at nonperipheral locations owing to degraded perfusion as opposed to the ones at peripheral sites [4]....

    [...]

Proceedings ArticleDOI
14 Oct 2008
TL;DR: It is suggested that reflected green light PPG had an advantage over reflected infrared PPG, especially at temperatures below 15°C, which indicated a stronger correlation between green PPG and ECG results at both temperatures.
Abstract: We evaluated the accuracy of pulse rate measurements obtained by reflected green light photoplethysmography (PPG) compared to reflected infrared light photoplethysmography and ECG. The wavelengths of the green and infrared light were 525 and 880 nm, respectively, and experiments were performed at 25°C and at a skin temperature below 15°C. The pulse rate obtained from reflected green light PPG was compared with the ECG RR interval and the pulse rate from reflected infrared PPG. The results indicated a stronger correlation between green PPG and ECG results at both temperatures. These results suggested that reflected green light PPG had an advantage over reflected infrared PPG, especially at temperatures below 15°C.

58 citations


"A novel sensor for wrist based opti..." refers background in this paper

  • ...Analyzing the effects of penetration depths and potential PPG content in the captured signal at the wrist with respect to the choice of wavelengths, green proves to be the choicest [6]....

    [...]

  • ...It is found that the signal quality for PPG signals from non-peripheral measurement sites is optimum for the green wavelength [9] and it is proven that green is superior to Infra-Red [6]....

    [...]

Proceedings ArticleDOI
05 Nov 2015
TL;DR: The results show that PulseOn provides reliability and accuracy similar to traditional chest strap ECG HR monitors during cardiovascular exercise.
Abstract: PulseOn is a wrist-worn optical heart rate (HR) monitor based on photoplethysmography. It utilizes multi-wavelength technology and optimized sensor geometry to monitor blood flow at different depths of skin tissue, and it dynamically adapts to an optimal measurement depth in different conditions. Movement artefacts are reduced by adaptive movement-cancellation algorithms and optimized mechanics, which stabilize the sensor-to-skin contact. In this paper, we evaluated the accuracy and reliability of PulseOn technology against ECG-derived HR in laboratory conditions during a wide range of physical activities and also during outdoor sports. In addition, we compared the performance to another on-the-shelf wrist-worn consumer product Mio LINK®. The results showed PulseOn reliability (% of time with error <10bpm) of 94.5% with accuracy (100% - mean absolute percentage error) 96.6% as compared to ECG (vs 86.6% and 94.4% for Mio LINK®, correspondingly) during laboratory protocol. Similar or better reliability and accuracy was seen during normal outdoor sports activities. The results show that PulseOn provides reliability and accuracy similar to traditional chest strap ECG HR monitors during cardiovascular exercise.

52 citations

Book
31 Oct 2011
TL;DR: This work serves as a comprehensive reference for graduate students in bioengineering and also provides solutions for medical researchers who are faced with the challenge of designing and implementing a cost-effective pervasive and ubiquitous wireless communication system.
Abstract: There has been a dramatic increase in the utilization of wireless technologies in healthcare systems as a consequence of the wireless ubiquitous and pervasive communications revolution. Emerging information and wireless communication technologies in health and healthcare have led to the creation of e-health systems, also known as e-healthcare, which have been drawing increasing attention in the public and have gained strong support from government agencies and various organizations.E-Healthcare Systems and Wireless Communications: Current and Future Challenges explores the developments and challenges associated with the successful deployment of e-healthcare systems. The book combines research efforts in different disciplines including pervasive wireless communications, wearable computing, context-awareness, sensor data fusion, artificial intelligence, neural networks, expert systems, databases, and security. This work serves as a comprehensive reference for graduate students in bioengineering and also provides solutions for medical researchers who are faced with the challenge of designing and implementing a cost-effective pervasive and ubiquitous wireless communication system.

45 citations


"A novel sensor for wrist based opti..." refers background in this paper

  • ...Continuous and accurate heart rate monitoring facilitates determination of heart rate variability indices [1] which are indicative of stress [2] and other cardio-logical disorders....

    [...]