ALG AVS111C-Y stereo module

Demo and values

GMSL2 stereo camera module from Shenzhen Aili-Light Technology (ALG Tech, 艾利光), with two global-shutter cameras 50 mm apart and a 6-axis IMU. One recording, solved as stereo + IMU. The recording matches ALG's AVS111C-Y; the exact model isn't confirmed by the maker.

No video on this page. The values below come from the solved run.

Reprojection median0.07 px

cam0–cam1 baseline49.9 mm

cam0 td−4.02 ms

cam0 lever arm53.9 mm

Reprojection is how far, in pixels, the detected corners lie from where the solve puts them. td is the camera–IMU time offset, and the lever arm is the camera–IMU position offset.

No independent reference, so these values show what MVIS solved, not how close they are to the truth.

Calibration process

The path of the rig around the board, as MVIS solved it. Press Play or drag the bar to follow it. Use the buttons to change the view.

▶︎ Playcam0cam1Loading

Board cornersRig path, darker is laterStartCurrent position

Solved rig

The solved rig in 3D, to scale. Tap a sensor to see its values. In full screen you can rotate and zoom. Grid squares are 20 mm.

3DFrontTopSide+−

To scale, from above and the front

From above

From the front

Camera	Lever x, y, z (mm)	Distance (mm)	log(R) (rad)	td (ms)	Field of view
cam0	+48.3, +16.2, −17.5	53.9	[−0.055, −3.133, +0.153]	−4.02	~120° × 76°
cam1	−1.5, +17.5, −18.0	25.1	[−0.038, −3.133, +0.163]	−4.03	~121° × 76°

Solved by MVIS. Lever arms (camera–IMU position offsets) are in the IMU frame. Rotation is log(R), camera in the IMU frame.

Specifications

Published by the maker
Maker	Shenzhen Aili-Light Technology (ALG Tech)
Closest published model	AVS111C-Y: 1280×800, 50 mm baseline, 120° × 76°, global shutter. Matched from this recording; the exact model isn't confirmed
Lens	1.67 mm, 120° horizontal on the AVS111C-Y sheet
IMU	6-axis, up to 6400 Hz on the sheet; 88 Hz in this recording
Link and power	GMSL2, power over coax, 9 to 12 V
Measured in these recordings
Cameras	2 × 1280×800, about 26 Hz in this recording
Shutter	Global on the AVS111C-Y sheet; a rolling-shutter solve finds no readout
Calibrated field of view	cam0 ~120° × 76° · cam1 ~121° × 76°

Sales contact Provided by the maker

Email	sales@aili-light.com
Phone	+86 755 2721 8150

Dataset

Recordings	1 recording, 24 s. cam0 623 frames, cam1 618, IMU 2,107 samples
Format	ROS2 bag, converted to EuRoC layout
Board	Chessboard 12×9 squares, 25 mm
Licence	None
Hosted	Not hosted

Chessboard 12 × 9 squares (11 × 8 inner corners), 25 mm squares, 300 × 225 mm. To scale

Detailed results

Lens Calibrated field of view

Calibrated field of view, horizontal × vertical. cam0: ~120° × 76°, corners reach 46° from the axis · cam1: ~121° × 76°, corners reach 50° from the axis

cam0 cam1

We read these from the calibrated lens fit at the image edges, through the principal point (where the optical axis meets the image). ~ marks an axis past where the corners reached, so the fit is extrapolated there. Past the fit means an edge lies beyond where the fit holds, so we give no value.

IMU Gyro–accel time offset t_ga −0.71 ms

Each bar shows a scale as its deviation from 1. IMU model: calyx. t_ga, the time offset between the gyroscope and accelerometer channels: −0.71 ± 1.72 ms.

Gyro scale x+4.49 %

Gyro scale y−1.44 %

Gyro scale z−0.78 %

Accel scale x+1.48 %

Accel scale y−1.93 %

Accel scale z+0.93 %

−8 %0+8 %

Timing cam0 td −4.02 ms

The time offsets, to scale. td is the camera–IMU time offset, with t_imu = t_cam + td.

Full results Every solved parameter

Rotation is log(R) in rad, camera in the IMU frame.

Parameter	MVIS
cam0
fx px	601.09
fy px	601.20
cx px	624.44
cy px	406.04
k1	0.00856
k2	0.02831
k3	−0.03534
k4	0.01620
Lever x mm	+48.33
Lever y mm	+16.17
Lever z mm	−17.54
log(R) rad	[−0.0546, −3.1331, +0.1528]
td ms	−4.018
Reprojection px	0.580
cam1
fx px	598.56
fy px	598.49
cx px	624.94
cy px	396.48
k1	0.01368
k2	0.01040
k3	0.00212
k4	−0.00991
Lever x mm	−1.54
Lever y mm	+17.46
Lever z mm	−17.98
log(R) rad	[−0.0380, −3.1329, +0.1629]
td ms	−4.029
Reprojection px	0.596
IMU
t_ga ms	−0.71 ± 1.72

Limits

• No independent reference, so these values show what MVIS solved, not how close they are to the truth.
• A simulation of this recording, solved the same way, shows its IMU samples (about 88 Hz, unevenly spaced) can't pin the IMU scales, the lever arm or the gyro-to-accel offset t_ga, even without noise. Treat those values as unreliable. The camera intrinsics and the stereo baseline aren't affected.
• With evenly spaced IMU samples at 150 Hz or more, the same simulation recovers most of it. The gyro scale and lever arm also need faster rotation than this recording has.
• The model is matched from resolution, baseline, field of view and shutter, not confirmed by the maker.

How it was run

• Both cameras and the IMU, global shutter, default IMU noise, t_ga estimated, camera intrinsics free. The IMU stored accel 4× and gyro 2× too small; both were scaled before solving. Batch of 2026-11-06.