1. Introduction
The WitMotion HWT9073 is a high-precision Attitude and Heading Reference System (AHRS) Inertial Measurement Unit (IMU) sensor. It integrates a 3-axis accelerometer, a 3-axis gyroscope, and a 3-axis magnetometer, utilizing an advanced fusion algorithm to provide accurate 3D data including acceleration, angular velocity, Euler angles, magnetic field, and quaternion. Designed for robust performance, it features IP67 waterproof protection and offers multiple communication interfaces (RS485 Modbus, CAN, TTL) for versatile applications such as tilt angle measurement.
2. Specifications
Figure 2.1: Detailed specifications of the HWT9073 sensor, including voltage, current, output data, range, accuracy, baud rate, return rate, size, weight, and direction options.
| Attribute | Value |
|---|---|
| Type | Acceleration Sensor |
| Output | Digital Output |
| Brand Name | WitMotion |
| Use | Tilt Angle Measurement |
| Voltage Input | 5-36V |
| Current | <30mA |
| Interface Level | RS485 (Modbus RTU protocol); CAN Series (Private protocol) |
| Output Data | 3D (acceleration, gyroscope, Euler angles, magnetic field) quaternion, time |
| Acceleration Range | ±2g |
| Angular Velocity Range | ±400°/s |
| Angle Range | X, Z±180°, Y±90° |
| X, Y Axis Accuracy | 0.001° (remain accurate under strong interference) |
| Z Axis Accuracy | 0.1° |
| Magnetic Field Accuracy | 1mg (milligauss) |
| Baud Rate | UART: 4800-921600, CAN: 3K-1M |
| Return Rate (CAN) | 0.2-200Hz |
| Size | 47*37*20MM (1.85*1.45*0.78 inch) |
| Weight | Sensor: 52.8g, Cable: 43.7g (Total approx. 96.5g) |
| Direction | Vertical or horizontal optional |
| Waterproof Rating | IP67 |
| Working Temperature | -40 to +85 degree Celsius |
3. Package Contents
The standard package for the HWT9073 sensor typically includes:
- WitMotion HWT9073 AHRS IMU Sensor
- Connecting Cable (length may vary by model, e.g., 5M for SINDT-RS485 5M)
- USB to Serial Converter (for PC connection)
- Digital Manual and Datasheet (available for download)
- PC Software (MiniIMU.exe, available for download)
- Sample Codes (available for download)
Figure 3.1: Illustration of available tutorial resources including serial drivers, sample code, PC software, and the manual.
4. Setup Instructions
4.1 Hardware Connection
- **Connect the Sensor:** Attach the sensor's cable to the appropriate interface on your system. For PC connection, use the provided USB to serial converter.
- **Connect to Converter:** Carefully connect the sensor's cable to the USB to serial converter.
- **Connect to PC:** Plug the USB end of the converter into an available USB port on your computer.
Video 4.1: Demonstrates connecting the sensor to a converter and then to a PC, showing multi-device connection and data display.
4.2 Software Installation
Before operating the sensor, install the necessary drivers and software on your computer:
- **Download Software:** Obtain the latest version of the PC software (MiniIMU.exe) and serial drivers from the official WitMotion website or provided resources.
- **Install Drivers:** Install the serial drivers for the USB to serial converter. Follow the on-screen instructions.
- **Install PC Software:** Run the MiniIMU.exe installer and follow the prompts to complete the software installation.
5. Operating Instructions
5.1 Launching the Software
Once the sensor is connected and drivers are installed, launch the WitMotion PC software (MiniIMU.exe). The software provides a dashboard for real-time data display and configuration.
5.2 Real-time Data Display
The software dashboard allows you to view various sensor outputs in real-time, including:
- 3-axis acceleration
- 3-axis angular velocity (gyroscope)
- 3-axis Euler angles (Pitch, Roll, Yaw)
- 3-axis magnetic field data
- Quaternion data
- Raw data
Figure 5.1: Software dashboard showing configurations, 3D DEMO, and real-time data curves and charts.
Figure 5.2: Comprehensive dashboard view with various sensor data points at a glance.
5.3 3D Demonstration
The software includes a 3D DEMO feature that provides a more intuitive visualization of the sensor's motion state. You can easily switch between different 3D models (e.g., car, helmet, cube, airplane) to observe how the sensor's orientation changes in real-time.
Figure 5.3: 3D demonstration feature for visualizing sensor orientation with different models.
6. Calibration
The HWT9073 sensor boasts a high accuracy of 0.001 degrees, achieved through rigorous calibration and advanced fusion algorithms. The calibration process ensures precise measurements even under strong interference.
Figure 6.1: Calibration and testing procedures, highlighting the 0.001° accuracy.
The PC software provides tools for calibration and configuration settings. Refer to the detailed software manual for specific calibration procedures to optimize performance for your application.
7. Maintenance
To ensure the longevity and optimal performance of your HWT9073 sensor, follow these maintenance guidelines:
- **Environmental Protection:** The sensor has an IP67 waterproof rating, making it suitable for severe environments. However, avoid prolonged submersion beyond its rated depth and protect it from extreme physical shock.
- **Cleaning:** Clean the sensor's exterior with a soft, dry cloth. Do not use harsh chemicals or abrasive materials.
- **Cable Care:** Inspect the connecting cable regularly for any signs of wear, cuts, or damage. Replace damaged cables immediately to prevent signal loss or short circuits.
- **Storage:** When not in use, store the sensor in a dry, dust-free environment within its specified operating temperature range (-40 to +85 °C).
- **Firmware Updates:** Periodically check the WitMotion official website for any available firmware updates to ensure your sensor has the latest features and performance enhancements.
Figure 7.1: The sensor's rugged design with IP67 waterproof aluminum casing, suitable for harsh environments.
8. Troubleshooting
If you encounter issues with your HWT9073 sensor, consider the following troubleshooting steps:
- **No Data Output:**
- Verify all cable connections are secure between the sensor, converter, and PC.
- Ensure the correct serial port is selected in the PC software.
- Check the power supply to the sensor (5-36V).
- Confirm that the serial drivers are correctly installed.
- **Inaccurate Readings:**
- Perform a calibration using the PC software.
- Ensure the sensor is placed on a stable, non-magnetic surface during initial setup and calibration.
- Check for strong magnetic interference in the operating environment, as the sensor is magnetic field resistant but extreme fields can affect readings.
- **Software Not Recognizing Sensor:**
- Restart the PC software and reconnect the sensor.
- Check your computer's Device Manager to ensure the USB to serial converter is recognized and functioning correctly.
- Try a different USB port on your computer.
9. User Tips
- **Data Format:** When connecting to a computer, the sensor typically sends data in a structured string format. Refer to the official datasheet or software documentation for the exact string format (e.g., for RS485 Modbus or CAN series private protocol) to ensure correct parsing.
- **Output Resolution:** The sensor provides high-resolution digital output. For specific analog output requirements (e.g., 4-20 mA), an external Digital-to-Analog Converter (DAC) might be required, depending on the specific model and interface.
10. Warranty and Support
WitMotion provides lifetime technical support for the HWT9073 sensor. For any technical assistance, warranty claims, or further inquiries, please contact WitMotion Official Store customer service or visit their official website for support resources.
