From 1f9a3dd1bd958f80ca429fbf4ebc6d4098f59653 Mon Sep 17 00:00:00 2001
From: Andrew Tridgell <andrew@tridgell.net>
Date: Mon, 4 Dec 2017 17:51:52 +1100
Subject: [PATCH] AP_AHRS: improved init attitdue in DCM

this tries harder to get a good IMU sample for the initial attitude
estimate. I have seen cases of bad IMU data on startup and this makes it
much less likely
---
 libraries/AP_AHRS/AP_AHRS_DCM.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/AP_AHRS/AP_AHRS_DCM.cpp b/libraries/AP_AHRS/AP_AHRS_DCM.cpp
index b5f6ecfa82..a8e0a2b05b 100644
--- a/libraries/AP_AHRS/AP_AHRS_DCM.cpp
+++ b/libraries/AP_AHRS/AP_AHRS_DCM.cpp
@@ -160,7 +160,7 @@ AP_AHRS_DCM::reset(bool recover_eulers)
         initAccVec = _ins.get_accel();
 
         // the first vector may be invalid as the filter starts up
-        while (initAccVec.length() <= 5.0f && counter++ < 10) {
+        while ((initAccVec.length() < 9.0f || initAccVec.length() > 11) && counter++ < 20) {
             _ins.wait_for_sample();
             _ins.update();
             initAccVec = _ins.get_accel();