Thread: Telemetry?
View Single Post
Old 01-07-2017, 06:01 AM   #30 (permalink)
Thunder Fighter
Registered Users
Posts: 5,243

Join Date: Jul 2007
Location: Melb, Oz

Originally Posted by extrapilot View Post
No, you cant, because it isn’t. Your approach towards measuring voltage in flight is not a good one- but that doesn’t mean good ones don’t exist, and aren’t every bit as capable as capacity-based systems. And more to the point, they function regardless of human error, and require no consideration for packs (no RFID, no capacity reset, no correction for state of charge or ambient temperature) other than the assumption of a fixed cell count for a given model. And if that changes and you dont realize it- you have bigger problems.
Well, I think I am entitled to my opinion based on the experience of 2 years and many hundreds of flights without a issue. I haven't seen a single documented case of filtered voltage being used with success in these multiple headspeed, multiple flight-style flights, so I'm not sure how you can say the method is better without showing evidence of someone actually using it.

Originally Posted by extrapilot View Post
Green is telemetry-based pack voltage. Red is what a basic low pass filter many people have tried (and disliked) looks like to your TX alarm logic. Yellow is what a simple, proper filter looks like. You see massive dips in the yellow trace? You see any dips that are not representative of actual pack voltage reduction? That seem too difficult to use as valid telemetry data? There are 2 passive components, retail $0.50 to put together. But why do that, when you can invest in a current integrator, RFID tags, a database to dynamically update your TX model scripts for the pack capacity, and a backup voltage monitoring system (which makes no sense if you already believe the data is invalid…) with its own conditional tests…
So what happens to that yellow trace if I land and make an adjustment just before the alarm goes off at the end of my pack and have the Heli sitting on the ground for a couple of minutes? The pack voltage will recover and your line will climb back up, then I take off and beat hard on the Heli, how far past the safe pack voltage will it let me fly before triggering the alarm?

Most of the new ESC's are now including capacity measurement that is available to telemetry systems, if your solution is so bulletproof and simple why are none of the manufacturers offering it, even as an option?

soXos Strike7 : soXos 600 : soXos 550 : soXos F3C 800
Protos 380 : soXos DB7 nightflyer : Jeti DS-16 & DS-12 : Mini Protos FBL Stretch : Logo 600
I am | VTX blades | 1st-RC Products | EGODRIFT motors
Thunder Fighter is offline        Reply With Quote