Marine motion sensor IMU-10X

Motion Reference Unit IMU-10x IMU-10x
Roll, pitch, heave, velocities and
accelerations motion sensor.
Model Roll/Pitch Heave
IMU-106 N/A 5cm or 5%
IMU-107 0.03° RMS N/A
IMU-108 0.03° RMS 5cm or 5%
IMU-108-30 (subsea) 0.03° RMS 5cm or 5%

The marine motion sensor IMU-10x series has been designed for multiple applications within the marine industry. Robust, versatile and accurate the IMU-10x motion sensor has an IP66 or IP68 titanium casing with high performance Micro Electro Mechanical System (MEMS) rate gyros and linear accelerometers which are processed by advanced algorithms producing a sensor for use in all dynamic environments.

Development over 10 years has produced a Motion Sensor suitable for applications from Active Heave Crane systems, Dynamic Positioning systems, Helideck Monitoring and other various Roll, Pitch and Heave motion applications.


Using a standard product design throughout the motion sensor range and with a product height of only 15 cm and width of 13 cm the SMC IMU-10x range is compact compared to equivalent products available today.

Motion reference unit dimensions Motion reference unit dimensions

Design principle

SMC’s product development and design philosophy is to produce technologically advanced, durable yet uncomplicated products. Our aim is to reduce the cost of purchase and maintenance by reducing options and add-ons often associated with ancillary products. By doing this SMC does not require that a client invests in extra equipment they already have installed on a vessel.

Titanium Material

The casing material used in all of our IMU-series is Titanium. The most useful properties of Titanium are its high strength, low density and corrosion resistance in the Marine environments the motion sensor works in.

Mounting plate

The IMU-10x has the mounting plate as a part of the casing, no additional mounting brackets are required for a standard installation.

In the design of the IMU-10x, SMC has reduced the accessory add-ons by incorporating the mounting plate in the base design reducing the standard purchase costs.

MRU mounting plate

Subsea Marine Motion Sensor IP68

For the submersible motion sensor IMU-108-30 depth rated for 30meter or optional 1000m, SMC has selected the IP68 classified Seacon Wet Mate Connector.

The IP68 standards classify the level of protection provided against the intrusion of dust and water.

Marine motion sensor IP68

Marine Motion Sensor IP66

For the standard surface marine motion sensor SMC selected the durable and easily sourced Amphenol Amphe-Lite 38999, series III, IP66 rated Mil spec composite connector. By selecting a readily available standard connection, clients have the security of long term supply and the ability to source cables and connectors from SMC or other suppliers.

Marine motion sensor IP66

Components and processing

The SMC marine motion sensors use solid state MEMS rate gyros that offer low noise and high accuracy as well as providing excellent vibration performance and long life reliability.

Three separate axial measurement component groups made of Gyroscopes, Accelerometers and Magnetometers are mounted in three axis for X, Y and Z measurements. The signal from the gyroscopes are combined with the signal from the accelerometers and magnetometers and are processed in a Kalman filter inside the motion sensor to provide output value for acceleration, attitude and angle with limited influence from accelerations, noise and other inaccuracies.

Heave is computed from a double integration of the acceleration into a linear position. The integration is further processed and filtered for an accurate heave measurement during dynamic environment.

Motion sensor Communication

As a standard all SMC marine motion sensors have 1 x RS232 and 1 x RS422 communication ports enabling the selection of Industry standard and bespoke output protocols. For aiding and data inputs 2 x RS232 serial ports are available. Ethernet connection is available as factory option, UDP output. Update Rates of 1 to 100Hz and 9600 to 115200 baud rates for selected protocols.

Aiding from Compass and GPS

SMC motion reference units can use inputs for aiding from standard industry GPS or Compass systems already installed on a vessel to improve measurement results during vessel turns. This is particularly useful for hydrographic surveying where 180° vessel turns between surveying lines is standard practice.

AHC Crane encoder feedback

Unique to the SMC motion sensor range is the SMC Active heave compensation AHC encoder feedback option. This was developed in conjunction with Bosch Rexroth drives but available for all users. The SMC AHC system accepts dynamic crane encoder position data, enabling continual calculation of the selected active heave measurement data to provide live motion compensation during critical marine crane operations.

Motion Sensor Configuration software

The marine motion sensor IMU configuration software enables quick and easy device setup in a structured display with user-friendly options and screen tabs for different industry applications.

Once the motion sensor has been mounted correctly it is easy to use the configuration software to modify the factory set up or change the configuration to a location/application specific installation.

Any setting changes made in the IMU Configuration software are written to the motion sensor flash memory that is not dependent on power supply or battery power.

Search functions and set up warnings provide protection against installation mistakes and the configuration can also be saved and exported to act as a backup and record of an installation.

Motion sensor protocols

SMC's standard NMEA 0183 protocol is just one of an increasing list of Industry Motion NMEA, Motion Binary and other common protocols (e.g. TSS1) that are installed as a default in the SMC motion sensors. These are all User Selectable from the SMC configuration software. The list includes Sector and Manufacturer standard protocols e.g. as used in the DP industry along with many Client Custom specific protocols that SMC has developed with our partners.

More information regarding the available protocols and details can be found in the SMC IMU Manual.


Each motion sensor is calibrated prior to delivery. The motion sensors are thoroughly tested in the SMC facilities before and during the calibration process. The calibration is performed in a 2- axis rate table with a temperature controlled chamber. The calibration process is fully automated and runs for three days with a controlled temperature environment over the full temperature range.

All motion sensors are calibrated individually and the readings from the accelerometers and angular rate gyroscopes are verified for alignment, linearity and temperature, to ensure they meet the performance specifications.

Technical specifications

Technical specifications IMU-106 IMU-107 IMU-108
Roll/Pitch N/A Yes Yes
Accelerations X, Y, Z N/A Yes Yes
Heave Yes N/A Yes
Angle Accuracy static N/A 0.02° RMS 0.02° RMS
Angle Accuracy Dynamic
@ ±5° simultaneous roll and pitch
N/A 0.03° RMS 0.03° RMS
Resolution Angle N/A 0.001° 0.001°
Resolution Heave 0.01m N/A 0.01m
Angle range Roll/Pitch ±30° ±30° ±30°
Heave range ±10m N/A ±10m
Heave Accuracy 5cm or 5% N/A 5cm or 5%
Acceleration accuracy N/A 0.01 m/s² RMS 0.01 m/s² RMS
IMU Configuration Software The IMU is shipped with SMC configuration windows software allowing on site setup
Output Signal Protocol Multiple, user selectable Output Protocols ASCII NMEA and binary
Communications Interface Output RS422 and RS232. Analog with remote converter (optional)
2 x RS232 External inputs, (not available on all models)
Velocity input formats RMC, RMA, VTG, VBV, VHW; Heading input formats HDT, HDG
Dimensions for IMU-10x (W x H) tube Ø89mm, mounting plate Ø134mm, flange Ø110mm x 127mm excl. connector
Weight ~2 kg
Housing Material Titanium
Temperature -20° to +65° Celsius (outside 0° to +55° Celsius, 0.1° angle performance); Storage Temperature -40° to +65° Celsius
Mounting Orientation Vertical or Horizontal mounting (factory set)
Power requirements 12 - 30 VDC; 2 W
MTBF (computed) 50 000 hours
Depth rating IP66 (standard); IP68 30 meter depth rated (optional)
Standard Complies with the IEC 60945
Warranty & Support      
Warranty 2-year Limited Hardware & Software Warranty
Support Free Technical & Hardware support
Bundled Delivery      
Junction Box Multiple Input & Output Connection Case, including 10 m cable


IMU-10x Motion Sensor Datasheet

SMC IMU Manual

316L Enclosure datasheet

GRP Enclosure datasheet

SMC IMU Configuration software