gee-dub

iTrader: (1)

Trolling thru the forums as one enjoys doing, I find interest in the number of users commenting about how much more 'connected' they feel when moving from one radio brand to another - when the latency differentials are in the 3-7ms range, while NOT correspondingly choosing to run the fastest available servo(s) at the highest available voltage(s). I mean if faster response=more connected=better, would not logic follow that only going part of the way (brain->hand->radio->receiver) is only part of the equation.

When discussing this topic in regards to steering servos, you start going down the road of response time vs. transit time vs. leverage, etc. There are threads already arguing the finer points therein.

But this got me thinking, why don't ESC vendors publish response time ratings? Maybe 0->7.4v/10A or 0->7.4v/10A->0? I mean, ESC's still have to receive signals and convert those signals thru some set of actions (processing, rotor position check, FET gate engagement (let's not even start the 'matched FET' conversation), etc.) in order for the electromechanical magic to happen.

Why isn't this information publicized? Are all ESC's the same? Are the differences 'too minor' to account for and, if so, what exactly is 'too minor'? Is there some great Russian hacking conspiracy taking place?

It seems like the speed/response time ratings have been a primary marketing point for servos since...forever and radio makers for the past couple of model generations. So, why not ESCs?

Grizzbob

iTrader: (2)

Not to throw water on the works, but I'd guess the answer is the common sense one you already mentioned, that the ESC manufacturers realize that ALL the electronics in our cars respond so fast that it's far beyond a human's ability to react. Consider this, a literal blink of the human eye takes about .25 sec., now convert that into milliseconds, & it becomes apparent that the entire process or control from the TX to the receiver to the ESC & servo & their response adds up to MUCH less than we can even blink, & our hands move much slower than that. The whole response time deal to me has looked like nothing more than marketing(though at least with servos, their transit times CAN make a difference, if one is particularly slow, & I have driven cars that have a very slow & cheap servo, & that definitely made it hard to drive for someone who is used to MUCH faster ones). But even combined, I don't think the response times of these things are nearly as big a deal as the manufacturers say...

billdelong

iTrader: (33)

+1

Servos are mechanical, varying quality of motors can only go so fast, some offer coreless, brushless, metal cases with bearings, etc... far too many variables which affect performance. In contrast, the "E" in ESC stands for "Electronic", nothing mechanical there to slow you down.... in fact most folks look for features to actually slow down their ESC, such as punch control, with stages or expo rates, etc.

While attending a race clinic last summer hosted by Ryan Lutz and Joe Bornhorst, they explained that having too fast of a servo can be detrimental as well (smoother is faster) and they recommend a servo somewhere in the 0.08 - 0.12 s/60° range. Watch that linked video and you'll get a better understanding of what the term "smoother" really means.