# FCU: Vision Failure for VIO

Source: https://forum.modalai.com/topic/2701/fcu-vision-failure-for-vio
Category: General Questions (https://forum.modalai.com/category/2/general-questions)
Posted: 2023-09-28 02:06:24 UTC by SMRazaRizvi
Replies: 1 · Views: 505

## SMRazaRizvi · 2023-09-28 02:06:24 UTC

I am using the VIO on a Sentinel, and I've configured it to use the Front Stereo Left camera.

However, I get the following error after a while when I start moving the drone.

```
FCU: Vision Failure
```

Please help.

***Important configurations:***

**voxl-qvio-server.conf**

```
{
	"imu_name":	"imu_apps",
	"cam_name":	"stereo_front",
	"lens_cal_path":	"/data/modalai/opencv_stereo_front_intrinsics.yml",
	"cam_extrinsics_name":	"stereo_front_l",
	"use_second_cam_if_stereo":	true,
	"odr_hz":	10,
	"use_camera_height_bootstrap":	true,
	"camera_height_off_ground_m":	0.085000000894069672,
	"enable_init_while_moving":	false,
	"cam_imu_timeshift_s":	-0.0020000000949949026,
	"cam_imu_timeshift_s_uncertainty":	0.0010000000474974513,
	"T_cam_wrt_imu_uncertainty":	[0.00050000002374872565, 0.00050000002374872565, 0.00050000002374872565],
	"R_cam_to_imu_uncertainty":	[0.00499999988824129, 0.00499999988824129, 0.00499999988824129],
	"accl_fsr_ms2":	156,
	"gyro_fsr_rad":	34,
	"accl_noise_std_dev":	0.31600001454353333,
	"gyro_noise_std_dev":	0.00999999977648258,
	"cam_noise_std_dev":	100,
	"min_std_pixel_noise":	0.5,
	"fail_high_pixel_noise_points":	1.6650999784469604,
	"limited_imu_bw_trigger":	25,
	"gps_imu_time_alignment_s":	0,
	"T_gps_wrt_imu":	[0, 0, 0],
	"enable_mapping":	true,
	"enable_gps_vel":	false,
	"en_auto_reset":	true,
	"auto_reset_max_velocity":	10,
	"auto_reset_max_v_cov_instant":	0.10000000149011612,
	"auto_reset_max_v_cov":	0.00999999977648258,
	"auto_reset_max_v_cov_timeout_s":	0.5,
	"auto_reset_min_features":	3,
	"auto_reset_min_feature_timeout_s":	1,
	"en_standby_mode":	true,
	"standby_skip_frames":	1
}
```

**extrinsics.conf**

```
{
	"name":	"Sentinel_V1",
	"extrinsics":	[{
			"parent":	"imu_px4",
			"child":	"imu_apps",
			"T_child_wrt_parent":	[0.0256, -0.0131, 0.0],
			"RPY_parent_to_child":	[0, 0, 0]
		}, {
			"parent":	"imu_apps",
			"child":	"tracking",
			"T_child_wrt_parent":	[0.0273, 0.0067, 0.0182],
			"RPY_parent_to_child":	[0, 45, 90]
		}, {
			"parent":	"imu_apps",
			"child":	"stereo_front_l",
			"T_child_wrt_parent":	[-0.00463019, -0.000268, -0.0008748],
			"RPY_parent_to_child":	[0, 0, 0]
		}, {
			"parent":	"imu_px4",
			"child":	"tracking",
			"T_child_wrt_parent":	[0.0529, -0.0064, 0.0182],
			"RPY_parent_to_child":	[0, 45, 90]
		}, {
			"parent":	"body",
			"child":	"imu_apps",
			"T_child_wrt_parent":	[0.0583, -0.0067, -0.0360],
			"RPY_parent_to_child":	[0, 0, 0]
		}, {
			"parent":	"body",
			"child":	"imu_px4",
			"T_child_wrt_parent":	[0.0327, 0.0084, -0.0360],
			"RPY_parent_to_child":	[0, 0, 0]
		}, {
			"parent":	"body",
			"child":	"stereo_front_l",
			"T_child_wrt_parent":	[0.0793, -0.040, -0.0243],
			"RPY_parent_to_child":	[0, 90, 90]
		}, {
			"parent":	"body",
			"child":	"stereo_rear_l",
			"T_child_wrt_parent":	[-0.0297, 0.04, 0.0415],
			"RPY_parent_to_child":	[0, -90, -90]
		}, {
			"parent":	"body",
			"child":	"tof",
			"T_child_wrt_parent":	[0.078, 0, -0.025],
			"RPY_parent_to_child":	[0, 90, 90]
		}, {
			"parent":	"body",
			"child":	"ground",
			"T_child_wrt_parent":	[0, 0, 0.058],
			"RPY_parent_to_child":	[0, 0, 0]
		}]
}

```

voxl-camera-server.conf

```
{
	"version":	0.1,
	"cameras":	[{
			"type":	"ov7251",
			"name":	"tracking",
			"enabled":	true,
			"camera_id":	2,
			"fps":	30,
			"en_preview":	true,
			"preview_width":	640,
			"preview_height":	480,
			"pre_format":	"raw8",
			"ae_mode":	"lme_msv",
			"ae_desired_msv":	60,
			"ae_filter_alpha":	0.600000023841858,
			"ae_ignore_fraction":	0.20000000298023224,
			"ae_slope":	0.05000000074505806,
			"ae_exposure_period":	1,
			"ae_gain_period":	1
		}, {
			"type":	"imx214",
			"name":	"hires",
			"enabled":	true,
			"camera_id":	3,
			"fps":	30,
			"en_preview":	false,
			"preview_width":	640,
			"preview_height":	480,
			"pre_format":	"nv21",
			"en_small_video":	true,
			"small_video_width":	1024,
			"small_video_height":	768,
			"small_venc_mode":	"h265",
			"small_venc_br_ctrl":	"cqp",
			"small_venc_Qfixed":	30,
			"small_venc_Qmin":	15,
			"small_venc_Qmax":	40,
			"small_venc_nPframes":	9,
			"small_venc_mbps":	2,
			"en_large_video":	true,
			"large_video_width":	1024,
			"large_video_height":	768,
			"large_venc_mode":	"h264",
			"large_venc_br_ctrl":	"cqp",
			"large_venc_Qfixed":	38,
			"large_venc_Qmin":	15,
			"large_venc_Qmax":	50,
			"large_venc_nPframes":	29,
			"large_venc_mbps":	30,
			"en_snapshot":	true,
			"en_snapshot_width":	4160,
			"en_snapshot_height":	3120,
			"ae_mode":	"isp"
		}, {
			"type":	"ov7251",
			"name":	"stereo_front",
			"enabled":	true,
			"camera_id":	0,
			"camera_id_second":	1,
			"independent_exposure":	false,
			"fps":	30,
			"en_preview":	true,
			"preview_width":	640,
			"preview_height":	480,
			"pre_format":	"raw8",
			"ae_mode":	"lme_msv",
			"ae_desired_msv":	60,
			"ae_filter_alpha":	0.600000023841858,
			"ae_ignore_fraction":	0.20000000298023224,
			"ae_slope":	0.05000000074505806,
			"ae_exposure_period":	1,
			"ae_gain_period":	1
		}, {
			"type":	"ov7251",
			"name":	"stereo_rear",
			"enabled":	true,
			"camera_id":	5,
			"camera_id_second":	4,
			"independent_exposure":	false,
			"fps":	30,
			"en_preview":	true,
			"preview_width":	640,
			"preview_height":	480,
			"pre_format":	"raw8",
			"ae_mode":	"lme_msv",
			"ae_desired_msv":	60,
			"ae_filter_alpha":	0.600000023841858,
			"ae_ignore_fraction":	0.20000000298023224,
			"ae_slope":	0.05000000074505806,
			"ae_exposure_period":	1,
			"ae_gain_period":	1
		}]
}

```

## Reply by SMRazaRizvi · 2023-09-28 18:32:18 UTC

@SMRazaRizvi @Moderator