I want to monitor Heart rate and other physiological parameters of a Driver in real life situations in different environment (Day/Night) using non-contact systems ( like camera). What are the main things to be considered ?
Your valuable thinking/ suggestions are appreciable.
We monitor HR by means of Laser Doppler Vibrometer and in such case the main limity is the necessity to maintain the laser spot in correspondence of the target artery (e.g. caortid). Maybe with the camera the ambient light is an important feature to be considered.
You may want to consider unobtrusive sensors based on pressure / capacitive / piezoelectric. You can get heart and respiration rate from the seat, provided there is no much vibration.
Dear Hamidur
This is a good question and the answer depends on many factors.
The problem with the camera is that the subject has to be always in the field of view. You need complicated algorithms to find the skin regions where you can sense a heart rate. The skin tone can affect also your readings. The variations in ambient light can affect your readings by superimposing to signal from skin. It will be difficult to remove this signal. I would go instead with sensors embedded in the steering wheel or in the safety/seat belt
A recent and interesting link regarding to this topic http://feedproxy.google.com/~r/Medgadget/~3/B-BFFbzKKU4/software-measures-heartbeats-in-video-recordings.html
For camera based methods, consistent ambient lighting is a very pressing problem. Depending on how complex (or accuracy during motion artifacts) you would like to measure, the seat pressure based HR measurement is a good method. You might wanna have a look at the attached article for completely unobtrusive non-contact measurement (even in the presence of some motion) using wifi signals.
http://www.extremetech.com/extreme/184347-mit-perfects-cheap-accurate-through-wall-movement-and-heartbeat-detection-with-wifi
In general,
Non-invasive, non contact method of recording any physiological parameters depends on three things
a. Source of signals, its anatomical location
b. Its surrounding organs and there interference/obstacles
c. sensing device and its properties.
Any organ deeper will always be surrounded by obstacles and hence there is a poor sensing .
Sensing device is accurate enough to pick the changes in the deeper activity only then its accuracy increases.
Coming to the Heart,
Beauty of the Heart is; it pumps or changes its anatomy at a specific time interval (60-90 beats per min) which its surrounding structures are silent or moving slowly(Lungs).
if you have a technology we can pick the change from outside by sending some waves like (ultrasound or IR). May be larger version of plethesmograpghy.
It a car. As receiver is can be kept at the driver seat and transmitter in front near the dashboard or vice versa.
better to place electrodes, or ppg sensors, micro cameras like in the phones on the driving wheel and then measure the heart rate. use the same technology, it way better than any camera method.
How accurate are the wrist-based heart rate monitors such as Polar M430?
I would like to know if there is any difference between heart rate monitors with chest band and the new models with wrist assessment such as Polar M430.