BW SENSING BW-IMU50 Series User manual

BW-IMU50 Series
Low-cost Inertial Measurement Unit
Technical Manual
V3.0

BW-IMU50
Low-cost Inertial Measurement Unit
Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
Introduction
BW-IMU50 is a low-cost 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-IMU50 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-IMU50 can be
greatly eliminated and the product accuracy level can be improved. BW-IMU50 has a digital
interface, which can be easily integrated into the user's system.
Feature
● Dynamic compensation, quadrature
compensation
● Gyroscope drift：150°/h
● Dump truck
● Balance car
● Stable platform
● AGV unmanned guided vehicle
● RS232 /485/TTL Output optional
● Wide temperature range：-40 ℃~+85℃，
Temperature compensation
● Small size：L55×W37×H24mm
● ROV underwater robot
navigation
● Marine survey
● Robots
● Unmanned aircrafts
Application

BW-IMU50
Low-cost Inertial Measurement Unit
Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
Product Feature
Electrical index
Power voltage
5V DC
Working current
30mA （40mA max）
Operating temperature
-40~85℃
Storage temperature
-55~100℃
Performance index
Gyro
Resolution
0.01°/sec
Range
±400°/sec
Bias stability at room
temperature
＜ 2°/h（ 100s,1σ）
＜ 150°/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.

BW-IMU50
Low-cost Inertial Measurement Unit
Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
Mechanical Index
Connector
Metal joint（Cable 1.5m)
Protection level
IP67
Shell material
Magnesium aluminum alloy anodizing
Installation
Four M4 screws
Package product size
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

BW-IMU50
Low-cost Inertial Measurement Unit
Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
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.

BW-IMU50
Low-cost Inertial Measurement Unit
Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
Signal
acquisition
terminal
IMU
RS232 Wiring diagram
RS485 Wiring diagram
IMU
Electrical Connection
Wiring Definition
Wiring color
function
RED
BLUE
BLACK
GREEN
YELLOW
1
2
3
4
5
VCC
DC 5V
NC
GND
Receive RXD
B、D-
Send TXD
A、D+

BW-IMU50
Low-cost Inertial Measurement Unit
Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
Debugging software
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-IMU50 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：
① Connect the serial port hardware of the inclinometer correctly, and connect the power
supply.
② Select computer serial port and baud rate and click connect serial port.
③ Click start button and the current inclination angle of the incliner in X and Y directions
will be displayed on the screen.

BW-IMU50
Low-cost Inertial Measurement Unit
Bewis Sensing Technology LLC www.bwsensing.com Tel: [phone]
Executive standard
Order information
Product model
Communication mode
Package situation
BW-IMU50-485
RS485
IP67 Package /Metal joint
BW-IMU50-232
RS232
IP67 Package /Metal joint
BW-IMU50-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

BW-IMU50 Series
Low-cost Inertial Measurement Unit
Wuxi Bewis Sensing Technology LLC
Add：Building 30, No.58 Xiuxi Road, Binhu District,
Wuxi City, Jiangsu Province, China
Tel：[phone]
Email：[e-mail]
Web：www.bwsensing.com