Skip to content

Xsens IMUs deliver sub-5 cm heave accuracy for maritime wave motion

The Sirius (above) and Avior IMUs now have the Heave function to account for wave motion.(Photo: Xsens)
The Sirius (above) and Avior IMUs now have the Heave function to account for wave motion.(Photo: Xsens)

Listen to this content

0:00 0:00

Firmware upgrade available for Xsens Sirius and Xsens Avior motion sensors delivers centimeter-level vertical displacement measurement for marine stabilization and control systems

Xsens has announced a major capability upgrade for its industrial-grade Xsens Sirius and Xsens Avior inertial measurement units (IMUs). The new Heave feature delivers centimeter-level vertical displacement measurement, enabling real-time stabilization and wave compensation in a wide range of marine applications. 

Marine engineers can now access comprehensive motion data — roll, pitch, yaw and Heave — from a single compact sensor. This eliminates the need for external processing or for oversized tactical-grade systems while maintaining the precision required for offshore platforms, vessels, docking systems, marine robots, buoys and surveying equipment.

The Heave output operates at up to 100Hz, providing the real-time response needed in active stabilization and wave compensation systems. All processing happens on-device, simplifying system integration and reducing latency.

Xsens motion reference units (MRUs) — IMUs with Heave capability — deliver real-time Heave accuracy better than 5 cm for wave periods up to 29 s. This covers most marine applications. For longer wave periods up to 40 s, accuracy is approximately 6cm, twice the range supported by comparable industrial-grade MRUs.

“Engineers now get vertical displacement data directly onboard, alongside roll, pitch and yaw,” said Ayush Sharma, Algorithms Engineer at Movella. “This gives marine customers the complete motion reference they need for stabilization and compensation systems, without the size or certification overhead of tactical MRUs.”

The algorithm uses proprietary phase correction and bias estimation to mitigate the effect of drift over extended operating periods. Users can also define offset points — center of rotation (COR) and point of interest (POI) — ensuring that Heave values reflect the true motion of the vessel or payload, even when the MRU is installed away from the POI.

The Heave algorithm is available for download immediately as a firmware update for existing Xsens Sirius and Xsens Avior units in the field, with no hardware modifications required. All new units ship with the feature integrated. Heave output is enabled with a single setting in the MT Manager software or the Xsens software development kit (SDK). 

Designed for straightforward integration

Xsens Avior is a compact OEM module for embedded system designs.

Xsens Sirius is a standalone MRU in a rugged IP68 housing for harsh environments. It meets MIL-STD-202 requirements.

Both products support RS-422, CAN, and UART interfaces. Development kits are available for prototyping, with free SDKs for C/C++, Python, ROS1, ROS2, and MATLAB. All units meet CE, FCC, and RoHS regulatory requirements, and are ITAR-free.

Xsens Avior and Xsens Sirius MRUs are available globally from Movella and authorized partners. For specifications, datasheets, and ordering information, visit www.movella.com/products/sensor-modules or contact a Movella sales representative.

If you enjoyed this article, subscribe to GPS World to receive more articles just like it.