specification · whatsapp:+86 13652339539 e-mail：[email protected] web： bluetooth 2.0...

https://wiki.wit-motion.com/english

WhatsApp:+86 13652339539 E-mail：[email protected] Web：https://wiki.wit-motion.com/english

Bluetooth 2.0 Gyro Sensor BWT61CL

SPECIFICATIONModel ：BWT61CL

Description ：Bluetooth 2.0 AHRS IMU sensor with battery

Quality system standard: ISO9001:2016

Tilt switch production standard：GB/T191SJ 20873-2016

Criterion of detection：GB/T191SJ 20873-2016

Revision date：2019.12.18Link to BWT61CL tutorial:(software, manual, etc.):

https://drive.google.com/file/d/1UBJ5AYxQZ81f1Wts1eKT6kOgwr9T8_qR

https://drive.google.com/file/d/1UBJ5AYxQZ81f1Wts1eKT6kOgwr9T8_qR/view

https://drive.google.com/drive/folders/1I6sBC-8Q3_vtY-GrFDZbWJZJFk7UnNfO

https://www.youtube.com/channel/UCxBLgvYQNk-sGVDp42ch-Ug

https://www.facebook.com/attitudesensor/




1 Description...................................................................................................- 3 -

2 Product parameters...................................................................................... - 4 -

3 Product display............................................................................................ - 5 -

4 Pin description............................................................................................. - 6 -

5 Axial direction............................................................................................. - 6 -

6 Connection...................................................................................................- 6 -

6.1 Serial connection...............................................................................- 6 -

6.2 PC Bluetooth connection.................................................................- 13 -

6.2.1 USB - HID connection............................................................ - 13 -

6.2.2 Connect to PC Bluetooth.........................................................- 14 -

6.3 calibration(calibration on PC software).......................................... - 16 -

6.3.1 Z-axis to 0................................................................................- 16 -

6.3.2 Accelerometer calibration....................................................... - 18 -

6.4 Data recording.................................................................................- 18 -

6.5 Installation direction........................................................................- 20 -

6.6 Dormancy and break dormancy...................................................... - 22 -

6.7 Static threshold and measure width.................................................- 22 -

6.8 Connect to Phone............................................................................ - 24 -

7 Communication protocol........................................................................... - 30 -

7.1 PC software to module.................................................................... - 30 -

7.2 Module to PC software....................................................................- 30 -

7.2.1 Acceleration output................................................................. - 31 -

7.2.2 Angular velocity output...........................................................- 32 -

7.2.3 Angle output............................................................................- 32 -

7.3 Date analysis and sample code........................................................- 34 -

7.4 Data analysis sample in embedded environment............................ - 34 -

8 Application area.........................................................................................- 38 -




1 Description

Chip BWT61CL was integrated to the Bluetooth battery sensor, Small and

delicate shell protects the module and it is convenient to carry. On the basis of

the original function, the Bluetooth interface is added. The wireless

transmission can be realized by connecting Bluetooth to the PC software.

The module integrated high precision gyro 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 .

The advanced digital filtering technology of this product can effectively

reduce the measurement noise and improve the measurement accuracy.

The attitude solver is integrated into the module, and the dynamic Kalman

filter algorithm can accurately output the current attitude of the module in the

dynamic environment.

An internal voltage stabilizing circuit module, voltage 3.3v~5v, pin

compatible with the 3.3V/5V embedded system, convenient connection.

Support serial port, convenient for users to choose the best way to connect.

It adopts stamp hole gilding process and can be embedded in user's PCB

board.




In the 4 layer PCB board process, thinner, smaller, more reliable.

2 Product parameters

1) Voltage: 3.3V-5V

2) Current: <40mA

3) Size : 51.3mm x 36mm X 15mm

4) Dimension: 2 Axis Angle(Roll Pitch) + 3 Axis Acceleration + 3 Axis Angular Velocity

+3 Axis Magnetic field

5) Range : Acceleration : ±16g + Angular Velocity : ±2000°/s + Angle: (X±180°,Y±

90°)

6) Stability: Acceleration : -0.01g Angular Velocity : -0.05°/s

7) Attitude measurement stability: 0.05°




8) Output content: Time, Acceleration , Angular Velocity, Angle (Roll Pitch)

9) Output frequency：0.1-100 Hz

10) Date interface: Serial TTL level Bate rate--115200(default and cant be changed)

11) Bluetooth transmission distance : >10m

12) Support for Android

3 Product display

Delicate shell, comes with 150MAH lithium battery, volume: 51.3mm x 36mm x

15mm,you can check the state of charge and power supply by the switch control

module




4 Pin description

5 Axial direction

As shown in figure above, The axis of the module is in the upper picture, upward

for x-axis, to the left for y-axis, Perpendicular to the paper, outward to the z-axis,

The direction of rotation is defined by the Law of the right hand. That is to say the

direction of four-fingers bending is the direction of rotation around the axis. The

thumb of the right hand points to axis.

6 Connection

6.1 Serial connection

Reminder: When connected with the sensor through Serial port cable connection,

you can only get the data and unable to set the sensor. If you need to set up the

sensor, you need a Bluetooth connection.




Hardware connection :

Module 3 in 1 Convert:

Driver installation:

First, install the driver CH340 when we used the USB serial module ,after installed

the driver. then get the corresponding Com number in the device manager. Driver

as followed:

https://wiki.wit-motion.com/english/doku.php?id=communication_module

https://wiki.wit-motion.com/english/doku.php?id=communication_module




Module 6 in 1 Convert:

Driver installation:

First, install the driver CP210X when we used the USB serial module ,after installed

the driver. then get the corresponding Com number in the device manager.

https://drive.google.com/file/d/1Y3Hs8RiAHhglAU0FOO9UwfwT7eForK

gA

https://drive.google.com/file/d/1Y3Hs8RiAHhglAU0FOO9UwfwT7eForKgA





After installing the module driver, and then Device Manager can query correspondingserial number, as below figure shows:





Connect with PC software

Open the software “MiniIMU.exe” and select the Com number

which you have got in the device manager before.

Click the menu “Type” , Select the model as “JY61” in the software.




Click the menu “Baud ”in the software and then select 115200, then the software

will show the data.

Clicking the button “Record” can save the data as a file.




The files are saved in the directory Data.tsv: of the software.




6.2 PC Bluetooth connection

6.2.1 USB - HID connection

Connect the USB -HID to the PC USB interface and turn on the attitude sensor. The

red led in the USB -HID is flashing, so is the blue led in the attitude sensor. which

means the Bluetooth is in the pairing connection




6.2.2 Connect to PC Bluetooth

When the PC has its own Bluetooth, you can search the device through the

Bluetooth directly.Take WIN10 for example:

1, Turn on the Bluetooth in the PC to search the device named “HC-6”,Right - click

on the device name to match.




2,Import the Bluetooth pairing password 1234, it will get the COM number

automatic when in wasfinished.

3,Open the Bluetooth and find the COM number.




4,Open the software, choose the Model, baud rate, and the COM number which

you have got before. The software will display the data.

6.3 calibration(calibration on PC software)

PS: Calibration in PC software can only be set up by connecting to Bluetooth. When

the module is used, you should calibrate it in advance.

6.3.1 Z-axis to 0

The module should be calibrated before you use it. The module calibrate includes

Z-axis to 0 ,Accelerometer calibration.

The z axis is 0 is the module z axis angle initial state is relative 0 degree angle




When the module is used before and z - axis drift is large, the z - axis can be

calibrated




6.3.2 Accelerometer calibration

The accelerometer calibration is used to get rid of the null bias of the

accelerometer. There will be different degrees of null bias in the sensors when they

firstly came out of the factory.

The calibration method is as follows:

Firstly, the module is kept horizontal and static, and the calibration is added. After

1 to 2 seconds, the three axial values of the module acceleration will be around 0 0

1 and the X and Y axis angles will be around 0°. The X Y-axis angle is more accurate

after calibration.

6.4 Data recording

There is no memory chip inside the sensor module，but the data can be saved by

PC software




Attention：The button”Record” can save the data as a file.

The saved files in the PC software Data.tsv：




6.5 Installation direction

The default installation direction of the module is horizontal installation. When the

module needs to be placed vertically,you can use the vertical installation setting.

Vertical installation method：Rotate the module around the X-axis and place it 90

degrees vertical when installing vertically ， Select the “vertical” in the “Config”

of the PC software.

Once the setting are completed,calibrate them to use.




6.6 Dormancy and break dormancy

Dormancy：The module pauses working and enters the standby state, dormancy

can reduce power consumption.

Break dormancy：The module enters the working state from the standby state.

How to use：The default state of the module is working state，Click “Sleep”in the

“config”of the PC software to enter the standby state, click “Sleep” again the

module will break the dormancy.

6.7 Static threshold and measure width

Static threshold ： The angular velocity of the gyroscope chip is slightly change

when the module is in static placement. The effect of the “Static threshold” is




When the angular velocity is less than the threshold module output angular

velocity is 0.

Bandwidth ： The module output the data within the measurement bandwidth.

Data greater than bandwidth is automatically filtered out.

How to use：Click the “Bandwidth ”of the “config ” in the PC software. default

is 10 HZ.




PS: The default setting of Static threshold and bandwidth works in most case. you

should not set it any more.

6.8 Connect to Phone

1) Install the app in the Phone, then turn on the Bluetooth sensor BWT61CL and

the Bluetooth in the Phone.

2) Search the Bluetooth connection in the Phone, the name of which was ”HC -06

" password is 1234.

3) When pairing is done, you will get the data through the Phone.

APP download address:

https://wiki.wit-motion.com/english/doku.php?id=bluetooth_inclinometer

https://wiki.wit-motion.com/english/doku.php?id=bluetooth_inclinometer




4) Calibration(calibration on App)

Please keep the BWT61CL on the horizontal level and make the “acceleration

calibration” and “Z axis return to zero” as below:

And the data will be valid for usage.




7 Communication protocol

Level：TTL level

Band rate：115200，Stop bit 1，check digit 0。

7.1 PC software to module

Introductions：

1.When the module is on, it needs to be static first. Because the MCU inside the

module will be aotomatically calibrated when it is in static. After calibration，the

angle of Z-axis will be initialize to 0. Which can be considered as a signal that have

been calibrated.

7.2 Module to PC software

Every frame data that the module sent to the PC software is divided into 3

packets,acceleration pocket, angular velocity packet and angle packet.




7.2.1 Acceleration output

Formula for calculating acceleration：

ax=((AxH<<8)|AxL)/32768*16g(g is gvality acceleration，9.8m/s2)

ay=((AyH<<8)|AyL)/32768*16g(g is gvality acceleration，9.8m/s2)

az=((AzH<<8)|AzL)/32768*16g(g is gvality acceleration，9.8m/s2)

Formula for calculating temperature：

T=((TH<<8)|TL) /340+36.53 ℃

Checksum：

Sum=0x55+0x51+AxH+AxL+AyH+AyL+AzH+AzL+TH+TL




7.2.2 Angular velocity output

Formula for calculating angular velocity:

wx=((wxH<<8)|wxL)/32768*2000(°/s)

wy=((wyH<<8)|wyL)/32768*2000(°/s)

wz=((wzH<<8)|wzL)/32768*2000(°/s)


T=((TH<<8)|TL) /340+36.53 ℃

Checksum：

Sum=0x55+0x52+wxH+wxL+wyH+wyL+wzH+wzL+TH+TL

7.2.3 Angle output




Formula for calculating angle:

Roll angle（x axis）Roll=((RollH<<8)|RollL)/32768*180(°)

The pitching angle（y axis）Pitch=((PitchH<<8)|PitchL)/32768*180(°)

Yaw angle（zaxis）Yaw=((YawH<<8)|YawL)/32768*180(°)


T=((TH<<8)|TL) /340+36.53 ℃

Checksum：

Sum=0x55+0x53+RollH+RollL+PitchH+PitchL+YawH+YawL+TH+TL

Attention：

1. The coordinate system used in the calculation of attitude angle is the northeast

coordinatesystem ， Place the module positivly, left is X-axis, front is X-axis.

upward is Z-axis.When the attitude is expressed by the Euler angle. Coordinate

rotation sequence is Z-Y-X.




7.3 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;



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;




break;

case 0x53:

Angle[0] = (short(chrTemp[3]<<8|chrTemp[2]))/32768.0*180;




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;

}

}

7.4 Data analysis sample in 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.




Interrupt unit(The following is AVR microcontroller code, different MCU reads the

register a little different):

unsigned char Re_buf[11],counter=0;

unsigned char sign;

interrupt [USART_RXC] void usart_rx_isr(void) //USART serial receiving interrupt

{

Re_buf[counter]=UDR; //Different micro-controller is slightly

different

if(counter==0&&Re_buf[0]!=0x55) return; //NO.0 data is not a frame

header ,skip.

counter++;

if(counter==11) //11 data has been received

{ counter=0; // Reassigned,ready for the next frame data reception

sign=1;

}

}

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;



T = (short(Re_buf [9]<<8| Re_buf [8]))/340.0+36.25;

break;

case 0x52:

w[0] = (short(Re_buf [3]<<8| Re_buf [2]))/32768.0*2000;




break;

case 0x53:




angle[0] = (short(Re_buf [3]<<8| Re_buf [2]))/32768.0*180;




break;

}

}

}




8 Application area

Agricultural machinery Internet of things

Solar energ Power monitoring

Medical instruments Construction machinery

Geological monitoring




WitMotion ShenZhen Co., Ltd

Bluetooth 2.0 Gyro Sensor BWT61CL

Contact: Mr. Kyle Tsang

E-mail : [email protected]

Skype: live:kyle_8394

WhatsApp: +86 136 523 39539

Amazon in USA: www.amazon.com/witmotion

Amazon in Canada: www.amazon.ca/witmotion

Amazon in Japan: www.amazon.co.jp/witmotion

Official Direct Store: www.aliexpress.com/store/4709011

Address : Honghai building 1405 Songgang town Baoan District

Shenzhen Guangdong Province China

mailto:[email protected]

https://www.amazon.com/witmotion

https://www.amazon.com/witmotion

https://www.amazon.co.jp/witmotion


specification · whatsapp:+86 13652339539 e-mail：[email protected] web： bluetooth 2.0...

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