The latest on inertial navigation systems. PIXEL recommends high-end equipment!
Heading and attitude measurements are of paramount importance during competition, especially for singlehanded saiboats on autopilot.
PIXEL sur MER installs a wide range of inertial navigation systems specific to each project.
Morgan and Jeff are giving you a glimpse at the many options available:
Traditional systems which have proven reliable
- Fluxgate technology :
Inertial system with mechanical platform and integrated gyroscope.
Jeff : « Nowadays, gyrocompass is the most used tool. But it has certain limits: measures of average quality when done at high speed, magnetic disturbance, limited accuracy and responsiveness (heading, roll, pitch), no access to accurate measurements of rotation speed and acceleration speed from 3 axes. »
- MEMS technology (MicroElectronical systeMS) :
A 9 datas inertial measure unit thanks to its 3 embedded sensors (3-axis gyrosocope, 3-axis accelerometer, 3-axis magnetometer).
Morgan : « These inertial systems have the advantage of being small. The technology has proven reliable, effective during regattas but more demanding if you’re racing around the world. Indeed, geomagnetic compensation algorithms are difficult to manage especially in the high latitudes of the southern hemisphere.
In such cases, PIXEL suggests a solution: integrating a high performance GPS which will improve signal reliability. The GPS helps to reset the magnetometers and reinforces the heading algorithm. The system will also improve the GPS’s accuracy.»
The fiber optic inertial system is for today
Fiber optic units for attitude meet the required standards for performance in sailing races.
In some instances, they add to the overall improvement of the GPS data and keep displaying both SOG and COG for a few seconds in case of a lost GPS signal.
These units are equipped with several data outputs allowing for their efficient and reactive integration into various systems at once (pilot, wind calculation…).
Jeff : « What improvements? Autopilot and wind calculation!
Compass heading is the most important data for the autopilot.
Even in wind mode, the pilot always refers to compass heading in order to reach its target.
The use of an accurate, reactive and low-noise true heading (insensitive to magnetic disturbances) is a major contribution towards the pilot’s quality.
In addition, direct acquisition of rotation speeds helps improving the anticipatory mode.
Wind measurement is subject to many disturbances.
Among them, the boat’s motions. A detailed knowledge of the boat’s attitude and motions allows for an accurate correction in wind calculation.
A well-corrected wind means less noise and thus an improvement in the use of the autopilot as well as in the helmsman’s mission.»
PIXEL sur MER’s involvement in the world of industry
The company DCI regularly calls on PIXEL sur MER’s expertise for the instrumentation and the settings of embedded electronic systems.
Our team works on communication and navigation equipments: radars, GPS, internal communication systems…
Our engineers also provide configuration, testing and validation procedures for the navigation system Sigma 40 (Sagem) based on ring-laser-gyro technology.
Sigma 40 provides all the data crucial for navigation: heading, roll and pitch, angular velocities, position and heave, vertical/horizontal velocities and accelerations…
Morgan : « It’s a must-have as far as fiber optic inertial system goes! Working in the world of industry is an added value for us, especially in the field of heading and attitude measurements. Using it during major challenges to come should be considered.»