Weathering the Storm: Multibeams Thrive in the World’s Harshest Conditions

The Tritech Gemini range of multibeam imaging sonars was designed to withstand the extremes this planet can bring with each product going through extensive testing and qualification to ensure they are the most robust sonars of their class in the industry.

The Gemini 1200ik dual frequency multibeam imaging sonar has been designed to operate in extreme temperatures (the sensor is still operational at -10°C and 35C°) and at depths of up to 350 m. Tritech’s commitment to producing extremely robust and reliable sensors sees the Gemini 1200ik completing shock and vibration testing as a standard part of the product’s qualification, as well as multiple rounds of pressure testing and open water tests. Despite its impressive durability, the sonar comes in at less than 1.5 kg in air and less than 0.5 kg in water.

The Gemini 1200ik offers users the ability to switch between high and low frequency manually or automatically through the software. Whether the sonar is operating at high or low frequency, it maintains the 120° horizontal field of view and offers an outstanding range resolution on high frequency of 2.4 mm.

Tritech is committed to continual product development and gains user feedback to understand what improvements and developments should come next. Alongside the improved image quality users have seen following the last firmware update, in 2023 further improvements to the Gemini 1200ik will be implemented including a greater depth rating and an optional built-in AHRS.

MICRO SONAR

Last year, Tritech launched the latest addition to their product range: the Micron Gemini.

Designed specifically with small and micro ROVs and AUVs in mind, the Micron Gemini is the smallest multibeam sonar in the world measuring a tiny 116 mm x 63 mm x 40 mm and weighing less than 0.5 kg in air and less than 0.25 kg in water.

The Micron Gemini is also an excellent sonar to transition into multibeam for those who have previously used small mechanically scanning sonars like the Tritech Micron Sonar. The Micron Gemini offers obstacle avoidance and navigation in low to zero visibility water conditions at low power requirements. This small but mighty machine also includes an integrated pressure sensor, depth readings, and a temperature sensor: reducing the need for additional payload on small vehicle bodies.

As well as these built-in sensors, the Micron Gemini has the optional addition of an Attitude Heading Reference system (AHRS). The AHRS provides users with readings of heading and pitch and roll to help pilots keep the ROV steady even when visibility is an issue.

Following its release in March 2022, the Micron Gemini has seen a great deal of success and popularity with integration into multiple small vehicles including Blueye Robotics’ underwater drones.

DIVER MOUNTED DISPLAY

The Micron Gemini has also been integrated, alongside the Gemini 1200ik and the Gemini 720ik multibeam imaging sonars, into Tritech Diver Mounted Display system (DMD). The DMD, which first launched in 2020, is popular with military and search and recovery divers. The system is comprised of a sonar, viewing monocle, subsea computer, and connecting cables, with the addition of either a battery pack or a topside Surface Control Unit (SCU), depending on the set up. The sonar is mounted at eye level with the monocle covering the diver’s non-dominant eye meaning the diver’s hands remain free. The system then allows a diver to locate targets, navigate towards them, and avoid obstacles along the way, all in zero visibility water conditions.

The DMD comes in two configurations: Tethered (DMD-T) and Untethered (DMD-U). The Tethered version connects the diver and the topside box by a 100 m tether and allows the topside team to communicate in real time with the Diver. The sonar data which is displayed on the diver’s monocle is also projected onto the SCU so the topside team can view and record the data while assisting the diver in their mission.

The Untethered version (DMD-U) gives the diver total freedom as the system is powered by battery packs which are pony-mounted so no tether is required. The untethered system is ideal for covert missions where there is a high risk of diver entanglement. The DMD-T can be converted into an DMD-U with the right additional equipment. Both Diver Mounted Display options are proving highly popular with multiple units already sold and large orders being prepared to ship in early 2023.

WORK CLASS ROV

As well as the Gemini 1200ik and the Micron Gemini, Tritech’s more established products include the Gemini 720ik and Gemini 720is. The Gemini 720is offers a depth rating of up to 4000 m and is seen as the industry standard multibeam imaging sonar for Work Class ROVs.

The Gemini 720is is available in two housings: aluminium and titanium. The titanium housing makes the sonar even more robust for hazardous water conditions where extra protection to the sonar is required. Tritech also offers Titanium as a housing option for many of their other sensors, outside of multibeam sonar range.

While the industry is typically seeing lead times for sensors of six months and beyond due to the whiplash of the COVID-19 pandemic and more recently Russia’s invasion of Ukraine, Tritech is usually able to supply within two months or shorter. This is in no small part thanks to the supplier relationships Tritech’s Supply Chain team have built up over the past 30 years and which they continue to work hard to maintain throughout these challenging times.

Tritech’s commitment to continual product development means that 2023 will lead to several new and exciting product enhancements, supporting Tritech’s mission to continuously improve the capacity to work in subsea environments by mitigating some of the risks that make underwater operations so hazardous.

For more information, visit: www.tritech.co.uk.

To read the full article, which was featured in ON&T Jan/Feb 2023, click here.