Monday, July 05, 2010

Milman-ed and Halkias-ed

Something happened today that made me realise that I need to stay in touch with engineering. Running at 10 km/hr, I was trying to figure out for twenty minutes, how the heart beat indicator on the tread mill works. Somehow, I couldn't quite figure out where the transducer was and I couldn't imagine it to be on the running pad. If so, imagine how sensitive the sensor should be and how much of amplification needs to be done.

The intrigue deepened when I noticed a small sticker proclaiming that it housed a wireless receiver. I can't imagine how a wireless receiver will work to retrieve heartbeat from a moving target. Even if it is a receiver, there *has* to be a transducer! Communication has never been my forte, but imagine the noise cancellation and the processing that needs to be done even to indicate in a fluttering colour scheme the heart rate of a very dynamically moving object.

Unless one has actually worked on a bread-board with transistors, he/she would not realise how tough it is to make the darned thing amplify. Compound this with VLSI techniques which can house millions of transistors in a small chip, designing it, testing it, give it an error tolerance. Multiply all this with the task of detecting microvolts of heart beat. Trust me, bio-signal processing is one of the toughest areas to work on.

Somehow it works out to be beautiful, isn't it?


RamNarayanS said...

Hey, I think you imagined way too much into this with your adroit imagination of signals and DSP. :-) The transducer must be in the hand grip. The wireless option would be only for an optional wrist strap or a neck or ear strap on which the transducer can monitor and send info wirelessly to the tread machine's base display or control unit. :-)

Uttara Ananthakrishnan said...

No! We don't grip it when we jog, without touching the hand grip. That is the whole beauty of this!

RamNarayanS said...

Mmmm... in that case, you can figure it out (from the manufacturer name) and let me know. What you describe sounds not too easy to me and not worth it to get into a simple treadmill. :) :) Or, they might use your discounted theory of using the step count, the belt speed and then approximate the rate of your heartbeat. :)