Kongsberg MRU S Motion Reference Unit (MRU) designed for fish-finding sonars and echo sounders

The fish sonar motion sensor

The MRU S roll, pitch and heave motion sensor is specially

designed for fish finding equipment.

Typical applications

The MRU S model is typically used for real-time roll, pitch and heave

compensation of fishery sonars and echosounders. In rough weather

conditions the MRU S provides vessel motion data to the fish finding

equipment to present a display free from wave motion due to vessel

rolling, pitching and heaving..

Function

This cost-effective MRU S model incorporates 3-axis Micro-Electro-

Mechanical-System (MEMS) sensors for both linear acceleration and

angular rate. This unit achieves high reliability by using solid state

sensors with no rotational or mechanical wear-out parts.

The unit is delivered with a Windows based configuration and data

presentation software.

In this software vector arms from where the MRU is mounted to the

centre of gravity (CG) and to two individually configurable monitoring

points (MPs), can be defined. The heave measurement can be output

in four different locations (the MRU itself, CG, MP1 and MP2) 

simultanously on the same serial line or Ethernet port. A typical

monitoring point is the transducer head.

Variables output

The MRU S outputs roll, pitch and heave, together with linear

acceleration and angular rate.

Digital I/O protocols

MRU data is available through both Ethernet interface and serial lines

enabling easy distribution of MRU data to multiple users on board

the vessel. Output protocols for commonly used sonar equipment are

available on two individually configurable serial lines and Ethernet/UDP.

FEATURES

• 0.1° roll and pitch dynamic accuracy

• Outputs real-time roll, pitch and heave measurements

• Outputs on RS-232. RS-422 and Ethernet

• High output data rate (200 Hz)

• Lever arm compensation to two individually configurable monitoring

points

• Small size, light weight and low power consumption

• Each MRU delivered with Calibration Certificate

• Selectable communication protocols in the Windows based MRU

configuration software

• Export license not required

• 2-year warranty