Simulators raise towage safety and tugboat operations

Proof of concept

“Modelling is important for port design and development,” says Mr Hardy. “Proof of concept is the first step in developing the port and training programmes.” Simulation modelling could include “detailed 3D tidal, current and tidal stream models for 24-hour periods and different days, covering river estuaries with seasonal runoff, which cause changes in water levels and current velocities.”  

These conditions impact tugboat operations and ship assistance, requiring “different sets of operational manoeuvring rules and risk factors.” Simulators can predict the effects of dredging on tidal and current flows and provide solutions to port operators.

In one of its latest projects, Kongsberg Digital’s simulators were used to help LNG Canada and HaiSea Marine develop the LNG export terminal in Kitimat, British Columbia, and the process of escorting, towing, manoeuvring and docking gas carriers.

“Modelling tug operations is an important component of port development,” says Mr Hardy. “It is critical for safety system analysis, analysing effects on hull forms at higher speeds and understanding the extreme limits of performance, such as employing render/recover winches during ship escort. 

For HaiSea, Kongsberg Digital simulated a gas tanker escort through a route from the Pacific Ocean to Kitimat of more than 200 nautical miles, for safety and operational requirements. It considered render/recovery winch performance, hours of winch operations, alternative routes and towage in environmental conditions. 

“LNG carrier escorting at 9-11 knots produces high levels of line loads, which could break towlines or the ship’s connection points, so pilots need alternative ways to employ tugs or halt ship transits if weather conditions mean tugs cannot operate,” says Mr Hardy.

“We can simulate tugboat responses in various environments, the performance limits of tugs, the practical lifecycle of winches, hours of operations and positioning of fenders.”  

Simulation also considers the designs of ships being assisted and how this changes towage and pushing operations and the tugs conducting them.  

“There could be different forces on ships and tugs. All of this is incorporated into proof of concept and training programmes,” says Mr Hardy.

Future models

Kongsberg Digital’s simulators have also assisted naval architects worldwide to adjust existing designs or develop new concepts, while models are updated with new architectural information from designers.

“Incorporating new designs is important. When we include more advanced aspects into the K-Sim models, there is a higher degree of confidence of the results compared with real life,” says Mr Hardy. 

“Some tugboat designs are unique in their hullform, and some can become very specialised. Shipping companies may ask why they need different tugs, but some operations are specific, so tugs are designed and operated for this.”  

For example, the extent and height of flares on container ships and LNG carriers require highly manoeuvrable tugs for escort and towage duties.

Simulators are also used for mooring analysis and practising ship-to-ship transfers, and simulating tug operations when attending oil loading offshore. “We can replicate connections in various sea states, forces on tugs, and towline and winch performance in various types of operations,” Mr Hardy adds.

The latest development in simulators is use of augmented reality (AR) and virtual reality (VR) where goggles are used instead of large graphical screens for the immersive experience. These are supplemented with hardware replicating consoles and controls on tugboats.

“VR is okay for visual cues, but operators need the tactile feel of controls and to monitor real instruments, such as emergency brakes for winches,” Mr Hardy says.

All the equipment is set within full-mission simulators and tug simulators with the master chair and wheelhouse consoles. With AR, less equipment is included, which makes it more economic and cost effective. 

“We get less hardware and the performance of 360° simulators in smaller packages,” Mr Hardy says. “AR will be incorporated in years to come in proof of concept and training simulators.”