Recording heart rate

[Genghis the Engineer]

One of the (aviation) research labs that I work with has been doing work on pilot workload in various environments. Mostly in the sim, but we're hoping to take that work into the air also.

Apart from systems such as NASA-TLX (which is basically questionnaire based) we've been using a heart rate monitor borrowed from the human factors lab down the road as an indicator of stress levels. Annoyingly, they now want it back so we have to buy our own.

A bit of searching suggests that the ideal device may be some form of recording pulse oximeter - whilst we're not currently interested in SpO2, it does no harm to have it. So we're thinking maybe this? (http://www.amazon.co.uk/Contec-Full-Colour-Oximeter-Analysis-Software/dp/B003LY6P8I/ref=sr_1_4?s=drugstore&ie=UTF8&qid=1288264570&sr=1-4).

Ultimately however, what I want to do is record heart rate against a timeline, so that this can then be merged into other data (flight recorder and voice recorder mostly - one interesting finding recently is that student pilots heart rates go up about 10% whenever they have to talk on the radio!). That and spend as little money as possible, and not intrude any more than necessary with the pilot being monitored.

Can anybody who has used these devices comment on whether this might be the right device, or point me at something more appropriate?

G

[safetypee]

G, haven’t used any of the new systems, but a very long time ago at RAE, the old style stick-on terminals and leads with a tape recorder gave good service (also had a pretty nurse who looked after things).

The interest was in the workload in a range of aircraft / operating roles (Alan Roscoe). This ranged from fighter / ground attack aircraft to more sedate 1-11 and HS 748 in fog flying – auto and manual landing.

Amongst the conclusions was that high ‘g’ levels in fighter aircraft involving physical workload changed the heart rate and masked the mental contribution.
For the fog flying there was some indication of the reverse. A few pilots could elevate their heart-rate in anticipation of a difficult mental task – assessing the visual scene and deciding to land or not. Thus the workload at the time of the task did not indicate any significant change although the pilots reported ‘working hard’.
In this task a better measure of mental workload was to require a verbal description of what was seen and how this related to the pending decision; high workload was reflected by reduced commentary and in the extreme silence.

I don’t recall that this was published, but it was part of the work which culminated in the Bedford Workload Rating Scale. This was used in the fog flying and has been used extensively since with good result.

Although there was considerable simulator work associated with the flight tests above, AFAIR none used heart rate monitoring, all used the rating scale.
I sensed that there was an unwritten belief that simulation could not generate the stress / workload associated with a real operation, thus there would be little meaningful change in heart rate – it’s all in the mind. This of course begs the question why the workload ratings in the simulator correlated reasonably well with actual flying.

[The SSK]

Did you consider a simple solution like a Polar HRM? Although best known in sports training applications their website (http://www.polar.fi/en/)also talks about ‘protective services’ – fire, police etc – so it’s not all about getting your fitness up, but when you’re not using it for your test purposes it could come in handy in the gym or pounding the pavement.

The higher-end models have data download, which would give you your timeline. My modest one doesn’t do that – I just eyeball it. It has also been my everyday watch for the last eight years.

[Genghis the Engineer]

I've been wondering that myself - the watches don't really seem to be right for our purpose but, from what I can gather on various websites, you can get a transmitting chest strap (http://www.amazon.co.uk/Oregon-WM100-Data-Logger-Download/dp/B000MIOVFA/ref=sr_1_cc_2?ie=UTF8&qid=1288303635&sr=1-2-catcorr) and a remote recorder (http://www.amazon.co.uk/Oregon-WM100-Data-Logger-Download/dp/B000MIOVFA/ref=sr_1_cc_2?ie=UTF8&qid=1288303635&sr=1-2-catcorr).

Has anybody used either options for data download and viewing?

G

[Loose rivets]

Just a couple of asides:


Some target shooting experts claim they can stop their heartbeat as they pull the trigger. I could get mine very slow, but never stopped it.

Shuttle astronauts were reported to run at ~180 BPM just prior to separation.

[homonculus]

The pulse oximeter wont work - it sits on a finger which has to stay motionless, and has significant motion artifacts.

The best way is a 24 hour ECG which is a small recorder with electrodes attached to the chest - very easy to apply and the subject will be unaware. but expensive in comparison.

The Polar pulse system is next best - I have used it with remote measurement on treadmills, but I havent used one which records.

[air pig]

You can use an ear lobe detector for O2 saturaion, but you wil have difficulty securing it due to head movement.

Regards

Air pig

[Genghis the Engineer]

Decision made, chest strap and remote recorder with software - just under £40 all in from Amazon.

I might try it on myelf first - fit to myself and go and do an hour's CT. It should be interesting to compare my own heart rate with phase of flight! If I plot geopotential altitude and heart rate against the same timeline, that should give a good first glance.

Thanks chaps,

G

[gingernut]

I'm pretty good with my index and middle finger. :)

Seems to have worked well for the past few years, and I've got a week off in December if it helps.

How deep are they going to scrutinise your data?

[Screwballs]

How did the data gathering excercise work out in the end? I was thinking of doing something along similar lines?

Screwballs

[Genghis the Engineer]

How did the data gathering excercise work out in the end? I was thinking of doing something along similar lines?

Screwballs

I confess, all sorts of things took over just after I bought them, so we've not tried them out yet.

G

[AvMed.IN]

Though little behind in joining this thread, I had used wireless Nexus–10® (Mind Media B.V. Information about the NeXus-10. (http://www.mindmedia.nl/english/nexus10.php)) physiological monitoring and feedback platform in simulator setting. It provides 6 channels, and if the budget permits, can be safely used in air as well.
Just in case, your budgeting improves, this may be a useful tool.

[Genghis the Engineer]

It might, I seem to have found a route to bring on some new full time researchers to look at some issues in relative safety, ergonomics, safety, etc. of various instrument configurations. We'll probably start that in the sim, but sim data is of limited value unless eventually we've flown experiments in a real aeroplane.

G

[Screwballs]

Thanks for getting back to the thread. Keep us posted if you find the time!

Screwballs