Mission Statement - De-Spinning the Pro-Taser Propaganda

Yeah right, 'Excited Delirium' my ass...

-------------------------------------------------------------------------

The primary purpose of this blog is to provide an outlet for my observations and analysis about tasers, taser "associated" deaths, and the behaviour exhibited by the management, employees and minions of Taser International. In general, everything is linked back to external sources, often via previous posts on the same topic, so that readers can fact-check to their heart's content. This blog was started in late-2007 when Canadians were enraged by the taser death of Robert Dziekanski and four others in a short three month period. The cocky attitude exhibited by the Taser International spokespuppet, and his preposterous proposal that Mr. Dziekanski coincidentally died of "excited delirium" at the time of his taser-death, led me to choose the blog name I did and provides my motivation. I have zero financial ties to this issue.

Tuesday, May 13, 2008

Open message to J. Patrick Reilly

CBC News: ...the charge from the weapon isn't deadly on its own because it's pulsed and not constant, said J. Patrick Reilly... [LINK]

Ah excuse me Mr. Reilly - don't forget Fourier.

The waveform from the X26 taser is primarily 19 Hz (according to all the manufacturer's specifications, and by examination of the waveform). And that fundamental low frequency component, and its many harmonics, are continuous 100% duty cycle for the entire five-second blast. [LINK]

And since you're a trained electrical engineer, you know that this Fourier Transform is not just a mathematical trick. These low frequency spectral components actually exist in the frequency domain. They're perfectly real. They're just another way of looking at the same reality.

Also - with continuous 100% duty cycle - so much for Kroll's 'chronaxie' (a time constant that he alleges preferentially protects the heart muscle as compared to the skeletal muscle). Since the X26 waveform is 5-seconds in duration and is continuous 100% duty cycle, then there is nothing more to say to the chronaxie, except bye-bye!

The older (introduced in 1999) M26 taser had a waveform that was much more symmetrical about the zero volts axis. This obviously means, to those of us that really understand Fourier in our bones, that the M26 waveform actually is a pulsed high frequency waveform with a very low duty cycle.

But the newer X26 taser's pulse has a long monophasic pulse after that distractingly-peaky arc phase. That long and low DC pulse, on the right hand side of their X26 waveform plot - please do not disregard it, makes the overall waveform 19 Hz (as they've admitted).



And since the X26 is 19 Hz, then it logically follows that it is continuous 100% duty cycle for the entire 5-second cycle.


And thus Kroll's 'chronaxie' suggestion is toast.


The X26 was introduced in 2003.

Plot of the raw taser-associated death rate per month (black line is six-month running average). Internal link to more details [LINK]

Find 2003 on the graph.

No comments: