WitMotion Shenzhen Co., Ltd| Datasheet Bluetooth AHRS IMU sensor | BWT61CL The Robust Acceleration, Angular Velocity, Angle Detector The BWT61CL is a Bluetooth 2.0 multi-sensor device, detecting acceleration, angular velocity, as well as angle. 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 BWT61CL 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 BWT61CL’s scientific name is AHRS IMU sensor. A sensor measures 3-axis angle, angular velocity, acceleration. Its strength lies in the algorithm which can calculate three-axis angle accurately. BWT61CL is an CE certified accelerometer. It is employed where the highest measurement accuracy is required.
2 Features Built-in WT61 module, for detailed parameters, please refer to the instructions. The baud rate of this device is 115200 and cannot be changed. The interface of this product only leads to a serial port, expansion port function is not available. The module consists of a high precision gyroscope and accelerometer sensor.
3 Specification 3.1 Parameter Parameter Specification Voltage 3.3V-5V Current <40mA Battery 250mAh, 3.7V Working hour A.4h every charge(battery) B.Power source of 5V Size 51.3mm x36mm X15mm/ 2.02" x 1.41" x 0.59" Output content Angle: X Y Z, 3-axis Acceleration: X Y Z, 3-axis Angular Velocity: X Y Z, 3-axis Time Output frequency 100Hz Interface Serial TTL level Baud rate--115200 (default, can not be changed ) Interface standard: SH2.
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 Angle/ Inclinometer X, Y, Z, 3-axis X, Z axis: ±180° Y axis: ±90° (Y-axis 90° is singular point) Accuracy:X, Y-axis: 0.05° Z-axis: 1° Angle of Z-axis will have accumulated error BWT61CL | Datasheet v20-0630 | http://wiki.wit-motion.
3.2 Size Parameter Specification Tolerance Length 51.3 ±0.2 Width 36 ±0.2 Height 15 ±0.2 Weight 20 ±0.2 BWT61CL | Datasheet v20-0630 | 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 Pin Definition PIN Function VCC 3.3-5V input supply RX Serial data input, TTL interface TX Serial data output, TTL interface GND Ground BWT61CL | Datasheet v20-0630 | http://wiki.wit-motion.
5 Casing Specification BWT61CL | Datasheet v20-0630 | http://wiki.wit-motion.
6 Communication Protocol Level：TTL level Band rate：115200, Stop bit 1, check digit 0. 6.1 Output Data Format BWT61CL | Datasheet v20-0630 | http://wiki.wit-motion.
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6.3 Date Analysis and Sample Code double a[3],w[3],Angle[3],T; void DecodeIMUData(unsigned char chrTemp[]) { switch(chrTemp[1]) { case 0x51: a[0] = (short(chrTemp[3]<<8|chrTemp[2]))/32768.0*16; a[1] = (short(chrTemp[5]<<8|chrTemp[4]))/32768.0*16; a[2] = (short(chrTemp[7]<<8|chrTemp[6]))/32768.0*16; T = (short(chrTemp[9]<<8|chrTemp[8]))/340.0+36.25; break; case 0x52: w[0] = (short(chrTemp[3]<<8|chrTemp[2]))/32768.0*2000; w[1] = (short(chrTemp[5]<<8|chrTemp[4]))/32768.
Angle[1] = (short(chrTemp[5]<<8|chrTemp[4]))/32768.0*180; Angle[2] = (short(chrTemp[7]<<8|chrTemp[6]))/32768.0*180; T = (short(chrTemp[9]<<8|chrTemp[8]))/340.0+36.25; printf("a = %4.3f\t%4.3f\t%4.3f\t\r\n",a[0],a[1],a[2]); printf("w = %4.3f\t%4.3f\t%4.3f\t\r\n",w[0],w[1],w[2]); printf("Angle = %4.2f\t%4.2f\t%4.2f\tT=%4.2f\r\n",Angle[0],Angle[1],Angle[2],T); break; } } BWT61CL | Datasheet v20-0630 | http://wiki.wit-motion.
6.4 Data Analysis Sample Under Embedded Environment The code is divided into two parts, one of them is interrupt reception. Find the header of the data and then put the data-packet into an array. The other one is data analysis, which is put into the main program section.
} Main program section： float a[3],w[3],angle[3],T; extern unsigned char Re_buf[11],counter; extern unsigned char sign; while(1) { if(sign) { sign=0; if(Re_buf[0]==0x55) //Check the frame header { switch(Re_buf [1]) {c ase 0x51: a[0] = (short(Re_buf [3]<<8| Re_buf [2]))/32768.0*16; a[1] = (short(Re_buf [5]<<8| Re_buf [4]))/32768.0*16; a[2] = (short(Re_buf [7]<<8| Re_buf [6]))/32768.0*16; T = (short(Re_buf [9]<<8| Re_buf [8]))/340.0+36.25; break; BWT61CL | Datasheet v20-0630 | http://wiki.wit-motion.
case 0x52: w[0] = (short(Re_buf [3]<<8| Re_buf [2]))/32768.0*2000; w[1] = (short(Re_buf [5]<<8| Re_buf [4]))/32768.0*2000; w[2] = (short(Re_buf [7]<<8| Re_buf [6]))/32768.0*2000; T = (short(Re_buf [9]<<8| Re_buf [8]))/340.0+36.25; break; case 0x53: angle[0] = (short(Re_buf [3]<<8| Re_buf [2]))/32768.0*180; angle[1] = (short(Re_buf [5]<<8| Re_buf [4]))/32768.0*180; angle[2] = (short(Re_buf [7]<<8| Re_buf [6]))/32768.0*180; T = (short(Re_buf [9]<<8| Re_buf [8]))/340.0+36.
7 Certification BWT61CL | Datasheet v20-0630 | http://wiki.wit-motion.
