Quote:
Originally Posted by glypo
Amps aren't anything really. Current is not the defining problem, it's power. Very basic Physics here. Current is obviously relative to power, but not the defining problem. Anyway lets say for a number of reasons we initially run around 7 volts to keep using standard ESC's etc. 7x20=140 watts. That's nothing. Mobile phone masts pump out factors more in terms of power. And you have to consider this is radiation, it's being emitted into a 3 dimensional environment. The actual power output is actually irrelevant really, rendering my above basic calcs useless, only good for comparison. What actually matters is the intensity of the radiation, and as I said 3D environment so you're talking about an exponential decay of radiation when you compare a linear distance from the wireless power transmitter. In fact just a couple of meters could mean factors less radiation.
In-fact I have just been typing some basic figures in my calculator and it would seem you would experience much more radiation from your microwave oven (all microwaves leak a bit) then from this technology. If it makes anyone feel safer, there is international legislation covering this stuff from the International Commission on Non-Ionizing Radiation Protection (ICNIRP), so we should be fine.
Funnily enough when I was in the first and second year of my bachelors degree I was planning to write my dissertation on wireless power for low level aircraft, mainly because one of the lecturers was an expert in the wireless power field. And my basic calculations showed that for low level (6,000ft) flight it was actually possible without frying anybodies brain providing 103 metres safety distance was kept from the transmitters. The technology is actually much more viable in use for cars on roads, and is being looked at in industry and academia as a way of getting around the battery/recharge problem on full size electric vehicles. Unfortunately my electronics lecturer left before the third year of the degree and luckily that lead me onto doing aerodynamics.... and as I'm sure I've demonstrated I've managed to lose most of my leccy skills lol. Anyway my point is, if it's safe and possible for massive vehicles, powering our little cars should be no problem.  |
Glypo
Some interesting comments. Athough this is a RC Car website, makes you smile when you read something connected with Work.
I have been many seminars relating to RF Radiation, particualy when the wireless market was booming, and everyone had fears relating to either Mobile Phones or Basestations. All those key words you remember SAR, Near field and Far field. Ionising and Non Ionising radiation. We work closely with a company called NSTS who design and manufacture the 'sniffers' that detect all these differant RF Fields also there is now available software to Map areas for 'hot spots'...
By the way, I am no expert on this, but the US Regalations, (so very much worldwide) state the maximum amount of leakage from the Oven at distances of 5cm = 1.0mWcm, (squared) and 5.0mWcm, (squared) throughout it's operating life.
Paul