From b626bfe2ccfa38813fe447a1892772e5583024a2 Mon Sep 17 00:00:00 2001 From: Stavros Korokithakis Date: Sun, 20 Dec 2020 00:53:08 +0200 Subject: [PATCH] Updates --- content/drone-stuff/inav-tuning-tips.md | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/content/drone-stuff/inav-tuning-tips.md b/content/drone-stuff/inav-tuning-tips.md index c2f8667..181ec1c 100644 --- a/content/drone-stuff/inav-tuning-tips.md +++ b/content/drone-stuff/inav-tuning-tips.md @@ -10,6 +10,15 @@ Here are some general INAV tuning tips and things I've learned throughout my bui * To make turns in automatic modes smoother, use `set nav_fw_control_smoothness = 8`. * Pawel says that the idea of the software LPF is to replace the hardware LPF. Leave the hardware LPF set to 256 Hz and set the software LPF to 20-30 Hz, with a looptime of 1k. + +## Battery monitoring + +To monitor how much battery you have left in flight, voltage isn't a good indication because it can sag a lot. mAh is also not a good indication, because it doesn't decrease linearly with voltage. Energy is a better way, using the "Wh drawn" INAV OSD item. In addition, INAV has heat loss compensation for the energy meter, which gives you a more accurate reading. + +To calculate the Wh a battery can give, the best way is to charge or discharge it and see how many Wh were spent, if your charger shows you. Another way is to get a rough estimate using the formula `no_cells * 3.7 * Ah`. So, for a 1800 4S battery, the maximum Watt-hours are `4 * 3.7 * 1.8 = 26.64 Wh`. **You should not discharge more than 80% of that value.** + +For a 4S battery, I go with a rule of thumb: The maximum Wh is `mAh / 100`, so for a 5000 mAh battery I'll start to land after 50 Wh consumed, which is around 70% of the battery consumed and gives a nice margin for error. + * * * -*Last updated on December 15, 2020.* +*Last updated on December 20, 2020.*