From 075495791aa1bf653b29c0ff841f5640e9d926bb Mon Sep 17 00:00:00 2001
From: SkyLi <SkyLiA7Mr@gmail.com>
Date: Sat, 30 May 2026 00:35:54 +0800
Subject: [PATCH] fix: change QuaternionEKF UpdateCount (uint64_t) to
 accel_lpf_inited (uint8_t)

UpdateCount was only used as a first-time-initialization flag for the
accel low-pass filter, not as a real counter. Replaced with a simple
uint8_t flag and moved the set to the first-update path.
---
 modules/algorithm/QuaternionEKF.c | 6 +++---
 modules/algorithm/QuaternionEKF.h | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/modules/algorithm/QuaternionEKF.c b/modules/algorithm/QuaternionEKF.c
index 27c06e5..db6902b 100644
--- a/modules/algorithm/QuaternionEKF.c
+++ b/modules/algorithm/QuaternionEKF.c
@@ -56,7 +56,7 @@ void IMU_QuaternionEKF_Init(float* init_quaternion,float process_noise1, float p
     QEKF_INS.ChiSquareTestThreshold = 1e-8;
     QEKF_INS.ConvergeFlag = 0;
     QEKF_INS.ErrorCount = 0;
-    QEKF_INS.UpdateCount = 0;
+    QEKF_INS.accel_lpf_inited = 0;
     if (lambda > 1)
     {
         lambda = 1;
@@ -140,11 +140,12 @@ void IMU_QuaternionEKF_Update(float gx, float gy, float gz, float ax, float ay,
     QEKF_INS.IMU_QuaternionEKF.F_data[20] = -halfgxdt;
 
     // accel low pass filter,加速度过一下低通滤波平滑数据,降低撞击和异常的影响
-    if (QEKF_INS.UpdateCount == 0) // 如果是第一次进入,需要初始化低通滤波
+    if (!QEKF_INS.accel_lpf_inited)
     {
         QEKF_INS.Accel[0] = ax;
         QEKF_INS.Accel[1] = ay;
         QEKF_INS.Accel[2] = az;
+        QEKF_INS.accel_lpf_inited = 1;
     }
     QEKF_INS.Accel[0] = QEKF_INS.Accel[0] * QEKF_INS.accLPFcoef / (QEKF_INS.dt + QEKF_INS.accLPFcoef) + ax * QEKF_INS.dt / (QEKF_INS.dt + QEKF_INS.accLPFcoef);
     QEKF_INS.Accel[1] = QEKF_INS.Accel[1] * QEKF_INS.accLPFcoef / (QEKF_INS.dt + QEKF_INS.accLPFcoef) + ay * QEKF_INS.dt / (QEKF_INS.dt + QEKF_INS.accLPFcoef);
@@ -213,7 +214,6 @@ void IMU_QuaternionEKF_Update(float gx, float gy, float gz, float ax, float ay,
     }
     QEKF_INS.YawTotalAngle = 360.0f * QEKF_INS.YawRoundCount + QEKF_INS.Yaw;
     QEKF_INS.YawAngleLast = QEKF_INS.Yaw;
-    QEKF_INS.UpdateCount++; // 初始化低通滤波用,计数测试用
 }
 
 /**
diff --git a/modules/algorithm/QuaternionEKF.h b/modules/algorithm/QuaternionEKF.h
index 26ab0a9..da9065f 100644
--- a/modules/algorithm/QuaternionEKF.h
+++ b/modules/algorithm/QuaternionEKF.h
@@ -30,7 +30,7 @@ typedef struct
     uint8_t ConvergeFlag;
     uint8_t StableFlag;
     uint64_t ErrorCount;
-    uint64_t UpdateCount;
+    uint8_t accel_lpf_inited;
 
     float q[4];        // 四元数估计值
     float GyroBias[3]; // 陀螺仪零偏估计值