WitMotion Shenzhen Co., Ltd|
AHRS IMU Sensor | HWT901B
HWT901B Ahrs IMU Sensor
The Robust Acceleration, Angular velocity, Angle , Magnetic filed & Air Pressure Detector
The HWT901B is a IMU sensor device, detecting acceleration, angular velocity, angle , magnetic filed as well as air pressure. The robust housing and the small outline makes it perfectly suitable for industrial applications such as condition monitoring and predictive maintenance. Configuring the device enables the customer to address a broad variety of application by interpreting the sensor data by smart algorithms and Kalman filtering.
BUILT-IN SENSORS
 | |||
| Accelerometer | Gyroscope | Magnetometer | Barometer |
Tutorial Link
Google Drive
Link to instructions DEMO:
WITMOTION Youtube Channel
HWT901B Playlist
If you have technical problems or cannot find the information that you need in the provided documents, please contact our support team. Our engineering team is committed to providing the required support necessary to ensure that you are successful with the operation of our AHRS sensors.
Contact
Technical Support Contact Info
Application
- AGV Truck
- Platform Stability
- Auto Safety System
- 3D Virtual Reality
- Industrial Control
- Robot
- Car Navigation
- UAV
- Truck-mounted Satellite Antenna Equipment
Overview
HWT901B’s scientific name is AHRS IMU sensor. A sensor measures 3-axis angle, angular velocity, acceleration, magnetic field and air pressure. Its strength lies in the algorithm which can calculate three-axis angle accurately.
HWT901B is employed where the highest measurement accuracy is required. HWT901B offers several advantages over competing sensor:
- Heated for best data availability: new WITMOTION patented zero-bias automatic detection calibration algorithm outperforms traditional accelerometer sensor
- High precision Roll Pitch Yaw (X Y Z axis) Acceleration + Angular Velocity + Angle + Magnetic Field + Air Pressure output
- Low cost of ownership: remote diagnostics and lifetime technical support by WITMOTION service team
- Developed tutorial: providing manual, datasheet, Demo video, PC software, mobile phone APP and 51 serial, STM32, Arduino, and Matlab sample code, communication protocol
- WITMOTION sensors have been praised by thousands of engineers as a recommended attitude measurement solution
Features
- Built-in WT901B module, for detailed parameters, please refer to the instructions.
- The default baud rate of this device is 9600 and could be changed.
- The interface of this product only leads to a serial port
- The module consists of a high precision gyroscope, accelerometer, geomagnetic field and barometer sensor. The product can solve the current real-time motion posture of the module quickly by using the highperformance microprocessor, advanced dynamic solutions and Kalman filter algorithm.
- The advanced digital filtering technology of this product can effectively reduce the measurement noise and improve the measurement accuracy.
- Maximum 200Hz data output rate. Output content can be arbitrarily selected, the output speed 0.2HZ~ 200HZ adjustable.
Specification
3.1 Parameter
| Parameter | Specification |
| ➢ Working Voltage | TTL:5V-36V |
| ➢ Current | <40mA |
| ➢ Size | 55mm x 36.8mm X 24mm |
| ➢ Data | Angle: X Y Z, 3-axis Acceleration: X Y Z, 3-axis Angular Velocity: X Y Z, 3-axis Magnetic Field : X Y Z, 3-axis Air Pressure : 1-Axis Time, Quaternion |
| ➢ Output frequency | 0.2Hz–200Hz |
| ➢ Interface | Serial TTL level, |
| ➢ Baud rate | 9600(default, optional ) |
Measurement Range & Accuracy | ||
| Sensor | Measurement Range | Accuracy/Remark |
| ➢Accelerometer | X, Y, Z, 3-axis ±16g | Accuracy: 0.01g Resolution: 16bit Stability: 0.005g |
| ➢Gyroscope | X, Y, Z, 3-axis -±2000°/s | Resolution: 16bit Stability: 0.05°/s |
| ➢Magnetometer | X, Y, Z, 3-axis ±4900µT | 0.15µT/LSB typ. (16-bit) PNI RM3100 Magnetometer Chip |
| ➢Angle/ Inclinometer | X, Y, Z, 3-axis X, Z-axis: ±180° Y ±90° (Y-axis 90° is singular point) | Accuracy:X, Y-axis: 0.05° Z-axis: 1°(after magnetic calibration) |
| ➢Barometer | 1-axis | Accuracy : 1m |
Accelerometer Parameters
| Parameter | Condition | Typical Value |
| Range | ±16g | ±16g |
| Resolution | Bandwidth =100Hz | 0.0005(g/LSB) |
| RMS noise | Placed horizontally | 0.75~1mg-rms |
| Static zero drift | -40°C ~ +85°C | ±20~40mg |
| Temperature drift | ±0.15mg/℃ | |
| Bandwidth | 5~256Hz |
Gyroscope parameters
| Parameter | Condition | Typical Value |
| Range | ±2000°/s | |
| Resolution | ±2000°/s | 0.061(°/s)/(LSB) |
| RMS noise | Bandwidth =100Hz | 0.028~0.07(°/s)-rms |
| Static zero drift | Placed horizontally | ±0.5~1°/s |
| Temperature drift | -40°C ~ +85°C | ±0.005~0.015 (°/s)/℃ |
| Bandwidth | 5~256Hz |
Magnetometer parameters
| Parameter | Condition | Typical Value |
| Range | Cycle count value (200) | -800uT to +800 uT |
| Linearity ±200uT | Cycle count value (200) | 0.60% |
| Measuring range | Cycle count value (200) | 13nT/LSB |
Pitch and roll angle parameters
Parameter | Condition | Typical Value |
| Range | X:±180° | |
| Y:±90° | ||
| Inclination accuracy | 0.1° | |
| Resolution | Placed horizontally | 0.0055° |
| Temperature drift | -40°C ~ +85°C | ±0.5~1° |
Heading angle parameter
Parameter | Condition | Typical Value |
| Range | Z:±180° | |
| Heading accuracy | 9-axis algorithm, magnetic field calibration, dynamic/static | 1° (without interference from magnetic field) |
| 6-axis algorithm, static | 0.5° (Dynamic integral cumulative error exists) | |
| Resolution | Placed horizontally | 0.0055° |
Module parameters
Basic parameters
Parameter | Condition | Min | Default | Max |
| Interface | UART | 4800bps | 9600bps | 230400bps |
| CAN | 3K | 250K | 1M | |
| Output content | On-chip time, acceleration: 3D, angular velocity: 3D, magnetic field: 3D, angle: 3D | |||
| Output rate | 0.2Hz | 10Hz | 200Hz | |
| Start time | 1000ms | |||
| Operating temperature | -40℃ | 85℃ | ||
| Storage temperature | -40℃ | 100℃ | ||
| Shockproof | 20000g | |||
Electrical parameters
Parameter | Condition | Min | Default | Max |
| Supply voltage | 5V | 12V | 36V | |
| Working current | Work（5V~36V） | 4.6mA（TTL） 8.9mA（232）8.5mA（485）21.3mA(CAN） |
3.2 Size
Parameter | Specification | Tolerance | Comment |
| Length | 55 | ±0.1 | Unit: millimeter. |
| Width | 36.8 | ±0.1 | |
| Height | 24 | ±0.1 | |
| Weight | 100 | ±1 | Unit: gram |
3.3 Axial Direction
The coordinate system used for attitude angle settlement is the northeast sky coordinate system. Place the module in the positive direction, as shown in the figure below, direction right is the X-axis, the direction forward is the Y-axis, and direction upward is the Z-axis. Euler angle represents the rotation order of the coordinate system when the attitude is defined as ZY-X, that is, first turn around the Z-axis, then turn aroundthe Y-axis, and then turn around the X-axis. 
PIN Definition
PIN | Color | Function |
| VCC | RED | Input Supply TTL : powered by 3.3-5V |
| RX | GREEN | Serial data input RX :connected with TX |
| TX | YELLOW | Serial data output TX :connected with RX |
| GND | BLACK | Ground GND |
Communication Protocol
Level: TTL level
Baud rate:4800, 9600 (default), 19200 38400, 57600, 115200, 230400, stop
bit and parity
Link to WITMOTION protocol.
HWT901B TTL
manual v230620
www.wit-motion.com
support@wit-motion.com
Documents / Resources
 | WiT HWT901B Ahrs IMU Sensor [pdf] Installation Guide HWT901B Ahrs IMU Sensor, HWT901B, Ahrs IMU Sensor, IMU Sensor, Sensor |
