A low-cost, bluetooth-based, ear-worn multi-parameter monitoring platform.
What is it?
“Raksh” – named after the sanskrit word safeguard – is a low cost (25$) bluetooth based ear worn multi parameter monitoring platform.
It non invasively and non obtrusively tracks a child’s respiration rate, heart rate(Pulse Plethysmography) , body temperature and a relative humidity of the child’s breath.
The data from the device is streamed to either a BLE compatible smartphone or a smart bluetooth internet gateway device which uploads the data to a server. The data is presented to a doctor on a web page or an app on the patient information using intelligent graphs and analytics highlighting abnormal conditions such as instances of Tachypnea (abnormal breathing) or high body temperature.
The doctor can also see the effect of medication provided by seeing changes in the various physiological parameters measured by the device enabling doctors to get accurate feedback of the condition of the child.
The doctor can then also modify the medication dosage accordingly.
This would enable medical aid organisations in rural areas who are extremely understaffed to assist more children.
The device would would also have alarm modes to alert parents to sudden onset a sudden fever or difficult breathing and the doctor would be able to remotely monitor and decide if a consultation is required.
“Raksh” would be a service based rental model to assist understaffed rural hospitals with poor doctor patient ratios.The service would enable doctors who previously could not give individual attention to each child to provide remote assistance to more patients.
The physical wearable device itself is provided on a rental model with an EMI (monthly payment ) option.
The device can then be collected after recovery of the child,it can quickly be reused with minimum maintenance.
The service leverages the internet to allow simple and reliable data sharing at a time when internet is becoming more and more accessible thanks to the efforts of Google’s project loon and Facebook’s internet.org. A service model would also be financially viable to low income households in developing countries that frequently rely on daily wage,They currently forgo from taking children to avail medical care fearing the cost involved.
How is it used?
The device is a small ear worn device with a slim low profile flexible sensor arm which is below the child’s nasal passage the design is inspired partly by modern hearing aids and headset microphone for our respiration sensor.
We chose the ear as the location as opposed to chest for not only comfort but also from a medical stand point.
The ear worn “Raksh” takes advantage of the ear cartilage (soft tissue) by gently clipping onto it to accurately measure the oxygen saturation and heart rate using pulse oximetry and photoplethymography thanks to lack of bone.
We are also able to track the respiration rate accurately by non invasive and accurately measuring minute changes in the nostril temperature compared to outside temperature using MEMS non-contact temperature sensors.
A micro sized MEMS temperature sensor is used to measure core body temperature which is part of the silicone plug that supports the device in the ear of the child.
What technologies does it incorporate?
Technology played a crucial role in the development of “Raksh” and we looked at current trends to keep the cost to a bare minimum.
Power management was a huge issue for us as our device needed to be compact and yet provide over two months of usage.
We chose the Bluetooth 4.0 enabled Nordic nRF51822 which also has a 32 bit ARM cortex M0 MCU for it’s low power needs and ample number of GPIO and communication,The BOM cost was inexpensive and perfect for our needs.We use the MBED platform for our firmware thanks to plethora of libraries and support of FOTA.
We are using the low cost TI i2c TMP007 non contact infrared temperature sensor to measure minute changes in the nasal passage temperature and by performing peak detection and by measuring reference room temperature, We can determine respiration rate accurately.
To accurately measure the heart rate and pulse oxygen content we chose to go with the MAX30100 Pulse oximetry sensor by Maxim Integrated, We developed our own custom photoplethysmography sensor based on the TAOS TSL12 but the size of the device increased and the cost of buying individual 535nm,650nm,940nm and the sensor increased BOM cost.
The MAX30100 however provided us an all in one solution with integrated LED’s and LED drivers.
The cost of this sensor was also low(3$) thanks to the rise and demand of fitness tracking wearables.
We have decided to go with a 180mAh rechargeable coin cell size Vatra Lithium-Ion batteries for the small size and large capacity. Our estimated battery life is about two month of continuous burst data streaming using frequent sleep cycles before needing a recharge.
The data is streamed to a server either via a smartphone (low end Android One phone) or a Bluetooth to GPRS gateway device that is provided with the device by the doctor that can be plugged to any wall socket and would contain a small battery for backup power, A small OLED screen on the gateway would provide basic parameters of the child’s health to the parent and would be a basic output console for the system.
Environmental parameters like smoke and dust content is also sensed by the gateway for doctors to monitor using the MICS-5526 sensor which looks at the Volatile Organic Compounds and other gases which may worsen respiratory ailment among kids.
How does it work?
The service is provided by rural hospitals that have very low doctor patient ratio by a child care doctor who has diagnosed a child with respiratory ailment.
Since the hospitals are distant from villages, a parent may not bring the child for regular examination and cannot afford expensive tests.
The doctor would prescribe the “Raksh” wearable device for the child to wear in an inexpensive EMI rental system a Bluetooth to internet gateway device is also provided to parents without a smartphone.
The device is easily customized by the doctor to fit the size of the child whose ages vary from 2-12 years before it is worn by the child.
The doctor can then remotely monitor the patient in real time and can also get notifications based on increased breathing rate or high temperature.
The child can be asked to be brought for tests if the conditions worsen and the data overall is useful for hospitals and healthcare services to plan their resources and assets.
Once the child has recovered the device is collected along with the gateway and is sent for minimal maintenance and is sanitized once before putting it to use again for a new child.
Who uses it?
*The data from the device is streamed through either a Bluetooth to internet gateway using GSM or a smartphone.
*The parent would be able to access the child’s health using the smartphone app or by using the OLED display on the internet gateway device.
*The doctor will be the only other person with access to the child’s health and can view the various parameters using a web-app or a smartphone app.
*After recovery the data on device is erased before reuse ensuring data security and the records are stored with the doctor for future reference.
Why does it help?
Our device provides a low cost method for remotely monitoring an child with respiratory ailment (pneumonia) and giving doctors access to crucial parameters of the patient allowing the doctor who otherwise gets a very small insight to the child’s condition due to shortage of time and lack of resources.
The device can also detect conditions of emergency and can instantly alert both the parent and the child while the data gathered can be used to track spread of epidemics by using data from different nodes.
Further doctors can also observe the effect of their medication and can remotely alter dosage just as they would in a hospital checkup.
By monitoring the environment using the gateway the doctor can find presence of indoor air pollution due to the cooking in “wood stoves”.
The data gathered can be using by healthcare organizations and rural hospitals to maximize their efficiency and manage their resources better to react to spread of epidemics in rural villages through water or food.
The device also would further bring more trust for the rural parents towards modern healthcare practices.
Vignesh Ravichandran, Manoj Kumar.B, Bharadwaj Ravichandran, Manoj Kumar.K.S
Alert/Response, Diagnosis/Treatment/Referral, Data Collection/Data Insight
Health, Child Protection
These pages have been pulled directly from applications submitted to the Wearables for Good Challenge in 2015. They represent the work of the individual teams and have subsequently not been edited.