BW SENSING BW-IMU127 Series User manual

Technical Manual
BW-IMU127 Series
Low-cost Modbus Inertial
Measurement Unit
V3.0

Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
BW-IMU127
Low-cost Modbus Inertial Measurement Unit
●Unmanned boat and underwater Robots
●Construction machinery
●Stable platform
●AGV unmanned guided vehicle
Application
BW-IMU127 is a high-precision strapdown inertial measurement unit that can measure the
angular velocity and acceleration of a moving carrier. The data deviation is estimated by the
6-state Kalman filter with appropriate gain, which is suitable for inertial attitude measurement
in motion or vibration state.
BW-IMU127 uses highly reliable MEMS accelerometers and gyroscopes, and it uses
algorithms to ensure measurement accuracy. At the same time, the sealing design and strict
production process ensure that the product can accurately measure movement parameters
such as the angular velocity, acceleration and attitude of the carrier in harsh environments.
Through various compensations such as nonlinear compensation, quadrature compensation,
temperature compensation and drift compensation, the error source of BW-IMU127 can be
greatly eliminated and the product accuracy level can be improved. BW-IMU127 has a digital
interface, which can be easily integrated into the user's system.
●Dynamic compensation, quadrature
compensation
●Accuracy：2°
●Special offset tracking algorithm
eliminates drift
●Gyro drift compensation
●RS232 /485/TTL Output optional
●Wide temperature range：-40 ℃~+85℃，
Temperature compensation
●High-performance Kalman filter
algorithm
●Small size：L55×W37×H24mm
●Heavy Truck
●Unmanned drive
●Robots
●Unmanned aircrafts
Introduction
Feature

Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
BW-IMU127
Low-cost Modbus Inertial Measurement Unit
Power voltage 9-35V DC
Working current 30mA （40mA max）
Operating temperature -40~85℃
Storage temperature -55~100℃
Gyro
Resolution 0.01°/sec
Range ±400°/sec
Bias stability at room
temperature
＜2°/h（100s,1σ）
＜100°/h（10s,1σ）
Angle random walk
coefficient
＜0.1 °/√h
Bias repeatability
＜50 °/h（1σ）
Scale factor non-linearity ≤100ppm（1σ）
Scale factor repeatability ≤100ppm（1σ）
Bandwidth 100Hz
Accelerometer
Range: X, Y, Z 2g
Resolution 0.01mg
Add zero offset 0.15mg
Bias stability 0.001mg（25℃，100s，1σ）
0.01mg（25℃，10s，1σ）
Resolution: The smallest change value of the measured value that the sensor can detect and
distinguish within the measurement range.
Accuracy: The root mean square error of the actual angle and the sensor measuring angle for
multiple (≥16 times) measurements.
Performance index
Electrical index
Product Feature

Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
BW-IMU127
Low-cost Modbus Inertial Measurement Unit
Mechanical Index
Connector
Metal joint（Cable 1.5m)
Protection level IP67
Shell material Magnesium aluminum alloy anodizing
Installation Four M4 screws
Product size：L55*W37*H24（mm）
PCB size
Product size：L33*W27*H6（mm）The length and width may have an error of
±1mm, please refer to the actual product
Package product size

Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
BW-IMU127
Low-cost Modbus Inertial Measurement Unit
Installation
The correct installation method can avoid measurement errors. When installing the
sensor, please do the following:
First of all, make sure that the sensor mounting surface is completely close to the
measured surface, and the measured surface should be as level as possible, and there should
be no included angles as shown in Figure A and Figure C. The correct installation method is
shown in Figure B and Figure D.
Secondly, the bottom line of the sensor and the axis of the measured object cannot have
an angle as shown in Figure E. When installing, keep the bottom line of the sensor parallel or
orthogonal to the axis of rotation of the measured object. This product can be installed
horizontally or vertically (vertical installation needs to be customized), and the correct
installation method is shown in Figure F.
Finally, the mounting surface of the sensor and the surface to be measured must be
tightly fixed, smooth in contact, and stable in rotation, and measurement errors due to
acceleration and vibration must be avoided.
the measured surface
uneven surface
generates the
angle
the measured surface
C D
AB
the measured surface the measured surface
uneven surface
generates the
angle

Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
BW-IMU127
Low-cost Modbus Inertial Measurement Unit
Wiring Definition
Wiring color
function
RED BLUE BLACKGREEN YELLOW
12345
VCC
DC 5V NC GND Receive RXD B、D- Send TXD A、D+
Electrical Connection
IMU
IMU
RS485 Wiring diagram
RS232 Wiring diagram
Signal
acquisition
terminal

Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
BW-IMU127
Low-cost Modbus Inertial Measurement Unit
You can download the serial debugging assistant directly on the official website
(technical service -> download area), or you can use the more convenient and intuitive host
computer software.
BW-IMU127 supporting serial port debugging software can connect the inclination
sensor on the computer to display the angle. The software debugging interface is shown in
the figure below. Using the tilt angle to debug the host computer, you can easily display the
current X and Y directions, and you can also modify and set other parameters.
Steps for use：
①Connect the serial port hardware of the inclinometer correctly, and connect the power
supply.
②Select the correct device model (Choose Azimuth Series).
③Select computer serial port and baud rate and click connect serial port.
④Click start button and the current inclination angle of the incliner in X and Y directions
will be displayed on the screen.
Debugging software

Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
BW-IMU127
Low-cost Modbus Inertial Measurement Unit
Product model Communication mode
Package situation
BW-IMU127-485 RS485 IP67 Package /Metal joint
BW-IMU127-232 RS232 IP67 Package /Metal joint
BW-IMU127-TTL TTL IP67 Package /Metal joint
●Enterprise Quality System Standard: ISO9001:2015 Standard (Certificate
No.064-21-Q-3290-RO-S)
●CE certification (certificate number: M.2019.103. U Y1151)
●ROHS (certificate Number: G 190930099)
●GB/T 191 SJ 20873-2003 General specification for inclinometer and level
●GBT 18459-2001 The calculation method of the main static performance index of
the sensor
●JJF 1059.1-2012 Evaluation and expression of measurement uncertainty
●GBT 14412-2005 Mechanical vibration and shock Mechanical installation of
accelerometer
●GJB 450A-2004 General requirements for equipment reliability
●GJB 909A Quality control of key parts and important parts
●GJB899 Reliability appraisal and acceptance test
●GJB150-3A High temperature test
●GJB150-4A Low temperature test
●GJB150-8A Rain test
●GJB150-12A Sand and dust experiment
●GJB150-16A Vibration test
●GJB150-18A Impact test
●GJB150-23A Tilt and rock test
●GB/T 17626-3A Radio frequency electromagnetic field radiation immunity test
●GB/T 17626-5A Surge (impact) immunity test
●GB/T 17626-8A Power frequency magnetic field immunity test
●GB/T 17626-11A Immunity to voltage dips, short-term interruptions and voltage
changes
Order information
Executive standard

Wuxi Bewis Sensing Technology LLC
Add：Building 30, No.58 Xiuxi Road, B
inhu District,
Wuxi City, Jiangsu Province, China
Tel：[phone]
Email：[email protected]
Web：www.bwsensing.com
BW-IMU127 Series
Low-cost Modbus Inertial
Measurement Unit