WitMotion WT901C 9-Axis AHRS IMU Accelerometer Gyroscope Magnetometer with Angle & Quaternion, 0.05 Accuracy, 0.2200 Hz, TTL/RS232/RS485 Modbus

Description

Overview

The WitMotion WT901C is a compact 9-axis AHRS IMU that fuses a 3-axis accelerometer, 3-axis gyroscope, and 3-axis magnetometer with WitMotions fusion/Kalman filtering to output angles (roll/pitch/yaw), angular velocity, acceleration, magnetic field, and quaternion. It delivers 0.05 static XY accuracy (0.1 dynamic), supports 0.2200 Hz update rates, and communicates over TTL, RS232, or RS485 (Modbus)ideal for inclination, vibration, and attitude measurement in automation, leveling platforms, VR/AR, and industrial testing.

Key features

• High accuracy AHRS: XY static 0.05, dynamic 0.1; right-hand Cartesian axes.

• Wide I/O & voltage: TTL 3.35 V, RS232/RS485 536 V, baud 4 800230 400 (default 9 600).

• Configurable output: 0.2200 Hz (default 10 Hz); user-selectable contents.

• Full 9-axis data: Acceleration, angular velocity, magnetic field, angle & quaternion.

• Visualization tools: Windows MiniIMU software with real-time graphs, raw-data logging/export (TXT), 3D motion demo, and visual magnetic calibration.

• Developer resources: Drivers (CH340/CP2102), manuals/datasheet, sample code for 51/C++/STM32/Arduino/Matlab, and Android app.

• Flexible install: Vertical or horizontal mounting; compact 51 36 15 mm, ~20 g.

Technical specifications

• Model/Brand: WT901C / WitMotion

• Interfaces: TTL / RS232 / RS485 (Modbus)

• Input voltage: TTL: 3.35 V; RS232/RS485: 536 V

• Current: < 25 mA

• Output data: 3-axis acceleration, gyroscope (angular velocity), magnetic field, angle, quaternion

• Measuring range: Acc 16 g; Gyro 2000 /s; Angle X,Z 180, Y 90

• Resolution: Acc 0.0005 g; Gyro 0.61 /s

• Stability: Acc 0.01 g

• Angle accuracy: XY static 0.05, dynamic 0.1

• Output frequency: 0.2200 Hz (default 10 Hz)

• Baud rate: 4 800230 400 (default 9 600)

• Size / Weight: 51 36 15 mm / 20 g

• Operating temp: 40 ~ 85 C

• Axis definition: Cartesian coordinates, right-hand rule

Dimensions & connector (TTL version)

• Body: 51.3 mm (H) 36.1 mm (W) 15 mm (D); mounting ears radius R1.5

• Connector: XH2.54-4P

• Pinout (leftright on label VCC/RX/TX/GND):

  1. VCC power 3.35 V

  2. TX Serial data input, TTL

  3. RX Serial data output, TTL

  4. GND ground

Note: Axis graphic is printed on the housing (X, Y, Z), aiding alignment.

Angle output protocol (frame 0x55 0x53)

Byte	Content	Meaning
0	0x55	Header
1	0x53	Angle frame ID
23	RollL/RollH	X-axis angle
45	PitchL/PitchH	Y-axis angle
67	YawL/YawH	Z-axis angle
89	VL/VH	Firmware version (low/high)
10	Sum	Checksum

Angle conversion:
Roll = ((RollH<<8)|RollL)/32768*180
Pitch = ((PitchH<<8)|PitchL)/32768*180
Yaw = ((YawH<<8)|YawL)/32768*180
(Acceleration and angular-velocity frames are similar; see manual.)

Software & tooling

• Windows (MiniIMU.exe): device config (ranges, bandwidth, output rate), real-time graphs, raw-data view, 3D pose visualization, export to TXT.

• Mag calibration: visual ellipse-fit workflow to reduce bias (rotate around X/Y/Z).

• MCU integration: direct serial connection; TTL recommended for simple MCU hookup (Arduino/STM32, etc.).

• Resources included: Datasheet.pdf, Manual.pdf, CH340 & CP2102 drivers, example code, Android App, demo videos.

Typical applications

Automation | Tilt/level monitoring | Vibration monitoring | Leveling platforms | IoT system integration | Industrial testing | VR/AR headsets | Consumer electronics.

Details

Cost-effective AHRS IMU with 0.05 accuracy in X and Y axes. Features inclination, vibration, and attitude sensing using WitMotion Fusion Algorithm. Includes acceleration, gyroscope, angle, magnetic, Kalman filtering, and quaternion functions.

WitMotion WT901C IMU offers 3-axis sensing with acceleration, gyroscope, and magnetometer. Provides quaternion output. Supports TTL, RS232, RS485. Measures 16g, 2000/s, 180 angles. Compact 513615mm size. Operates from -40 to 85C.

WitMotion WT901C IMU supports automation, VR headsets, leveling, and vibration monitoring. It works for consumer electronics, IoT, industrial testing, and AR/VR. Comes with free software for real-time angle data display.

WitMotion WT901C IMU config menu allows sensor calibration, data output settings, and real-time motion visualization. It supports 9-axis algorithm, adjustable acceleration, gyro, bandwidth, GPS time zone. Real-time graphs show acceleration and angular velocity for precise measurement.

WitMotion WT901C IMU offers powerful data storage, easy TXT export, and 3D motion visualization with available source code.

Visualizable magnetic calibration for WT901C IMU with ellipse fitting method. MCU connection via TTL interface recommended. Sensor connects to Arduino-like MCUs using VCC, RX, TX, GND pins.

Development Kits include free software for Windows, manual, datasheet, CH340 & CP2102 drivers, sample codes for 51, C++, STM32, Arduino, and Matlab, along with demo videos and Android app.

Data structure for WT901C IMU angle output includes header, roll, pitch, yaw, firmware version, and checksum. Formulas for calculations and verification are provided. Similar structures exist for acceleration and angular velocity.