WitMotion Shenzhen Co., Ltd | Datasheet Bluetooth AHRS IMU sensor | WT901BLECL The Robust Acceleration, Angular velocity, Angle & Magnetic filed Detector The WT901BLECL is a Bluetooth 5.0 multi-sensor device, detecting acceleration, angular velocity, angle as well as magnetic filed. The robust housing and the small outline makes it perfectly suitable for industrial applications such as condition monitoring and predictive maintenance.
Tutorial Link Google Drive Link to instructions DEMO: WITMOTION Youtube Channel WT901BLECL 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.
Contents Tutorial Link............................................................................................................................. - 2 Contact....................................................................................................................................... - 2 Application................................................................................................................................ - 2 Contents.............................................................
1 Overview WT901BLECL’s scientific name is AHRS IMU sensor. A sensor measures 3-axis angle, angular velocity, acceleration, magnetic field. Its strength lies in the algorithm which can calculate three-axis angle accurately. WT901BLECL is an CE certified accelerometer. It is employed where the highest measurement accuracy is required.
2 Features Built-in WT901BLE module, for detailed parameters, please refer to the instructions. The baud rate of this device is 115200 and cannot be changed. The module consists of a high precision gyroscope, accelerometer and geomagnetic field sensor. The product can solve the current real-time motion posture of the module quickly by using the high-performance microprocessor, advanced dynamic solutions and Kalman filter algorithm.
3 Specification 3.1 Parameter Parameter Specification Voltage 3.3V-5V Current <40mA Battery 250mAh, 3.7V Working hour A. Play 10h at 1 charge (battery) B. Power source of 5V Size 51.3mm x36mm X15mm/ 2.02" x 1.41" x 0.59" 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 Time, Quaternion Output frequency 0.
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) Angle/ Inclinometer X, Y, Z, 3-axis X, Z-axis: ±180° Y ±90° (Y-axis 90° is singular point) Accuracy:X, Y-axis: 0.
3.2 Size Parameter Specification Tolerance Length 51.3 ±0.2 Width 36 ±0.2 Height 15 ±0.2 Weight 20 ±0.2 WT901BLECL | Datasheet v20-0707 | Comment Unit: millimeter. Unit: gram http://wiki.wit-motion.
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 forward is the X-axis, the direction left 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 Z-Y-X, that is, first turn around the Z-axis, then turn around the Y-axis, and then turn around the X-axis.
4 Port Definition Ports Micro-USB Switch Function 3.3-5V power charge input , TTL interface Power ON/ OFF WT901BLECL | Datasheet v20-0707 | http://wiki.wit-motion.
5 Casing Specification WT901BLECL | Datasheet v20-0707 | http://wiki.wit-motion.
6 Communication Protocol 6.1 Data Format Module upload Flag=0x61 (Angle, Angular velocity, Acceleration) data default. Flag=0x71(Magnetic field) need to send the corresponding register instruction. Upload data format of Bluetooth: uploads up to 20 bytes per data 6.1.1 Data Packet(Default) Packet heading 1Byte Flag bit 1Byte axL axH …… YawL YawH 0x55 Flag 0xNN 0xNN …… 0xNN 0xNN Note: 0xNN is an accurate value received.
0x55 Packet header 0x61 Flag bit axL X Acceleration low 8 byte axH X Acceleration high 8 byte ayL Y Acceleration low 8 byte ayH Y Acceleration high 8 byte azL Z Acceleration low 8 byte azH Z Acceleration high 8 byte wxL X Angular velocity low 8 byte wxH X Angular velocity high 8 byte wyL Y Angular velocity low 8 byte wyH Y Angular velocity high 8 byte wzL Z Angular velocity low 8 byte wzH Z Angular velocity high 8 byte RollL X Angle low 8 byte RollH X Angle high 8 byte PitchL
Note: 1. The coordinate system used for attitude angle settlement is the northeast sky coordinate system. Place the module in the positive direction, as shown in Chapter 3.3, direction forward is the X-axis, the direction left 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 Z-Y-X, that is, first turn around the Z-axis, then turn around the Y-axis, and then turn around the X-axis. 2.
6.1.2 Single Return Register Data Packet Single return data packet needs to send register instruction first: FF AA 27 XX 00 --XX is register number. The register number please refer to 6.3. Example as below: Function Instruction Read Magnetic Field FF AA 27 3A 00 Read Quaternion FF AA 27 51 00 Read Temperature FF AA 27 40 00 After sending the instructions, the module will turn back a data packet 0x55 0x71. There are register addresses and 7 registers data (Fixed upload 8 registers).
6.1.2.1 Magnetic Field Output 0x55 0x71 0x3A 0x00 HxL HxH HyL HyH HzL HzH ...... Calculated formular：Unit: mG Magnetic field (x axis) Hx=(( HxH<<8)| HxL) Magnetic field (y axis) Hy=(( HyH <<8)| HyL) Magnetic field (z axis) Hz =(( HzH<<8)| HzL) For example: Send instruction to read magnetic field in APP: FF AA 27 3A 00 (Please refer to 6.1.2) The module return data to APP: 55 71 3A 00 68 01 69 00 7A 00 00 00 00 00 00 00 00 00 00 00 Total: 20 bytes. Calculate the no.5 to no.
6.1.2.3 Temperature Output 0x55 0x71 0x40 0x00 TL TH ...... Calculated formular： T=((TH<<8)|TL) /100℃ WT901BLECL | Datasheet v20-0707 | http://wiki.wit-motion.
6.2 Commands 6.2.1 Read Register Value FF AA 27 XX 00 Read register value --XX is register. For example:: Read magnetic field：FF AA 27 3A 00 Read quaternion： FF AA 27 51 00 Read temperature： FF AA 27 40 00 After send instructions, the module turns back a data packet 0x55 0x71. There are register addresses and 7 registers data (Fixed upload 8 registers). 6.2.
6.2.3 Save Settings FF AA 00 SAVE 00 Save Settings SAVE：Set 0：Save current configuration 1：Restore default configuration and save 6.2.4 Return Rate FF AA 03 RATE 00 Set return rate RATE：return rate 0x01：0.2Hz 0x02：0.5Hz 0x03：1Hz 0x04：2Hz 0x05：5Hz 0x06：10Hz(default) 0x07：20Hz 0x08：50Hz WT901BLECL | Datasheet v20-0707 | http://wiki.wit-motion.
6.
0x34 AX X Acceleration 0x35 AY Y Acceleration 0x36 AZ Z Acceleration 0x37 GX X Angular velocity 0x38 GY Y Angular velocity 0x39 GZ Z Angular velocity 0x3a HX X Magnetic field 0x3b HY Y Magnetic field 0x3c HZ Z Magnetic field 0x3d Roll X Angle 0x3e Pitch Y Angle 0x3f Yaw Z Angle 0x40 TEMP Module temperature 0x41 D0Status D0 Status 0x42 D1Status D1 Status 0x43 D2Status D2 Status 0x44 D3Status D3 Status 0x49 RSV Reserved 0x4a RSV Reserved 0x4b RSV Rese
