Knowing how vessels move in waves helps designers check passenger comfort.
How do you evaluate comfort during early-stage yacht design?
Yacht motion in waves – like pitch, roll, and heave – directly affects the quality of life for passengers onboard. Naturally, yacht owners want assurance that their vessel will be comfortable and that passengers will not get seasick. Ship motion prediction software gives insight into the motions and accelerations of any ship in waves. However, there is a nuanced relationship between these motions and accelerations and human comfort at sea, and calculations and techniques for evaluation are complex. What’s needed is a simple, standardized way to evaluate comfort based on motion data.
ISO 22834:2022 provides a roadmap for how to rate ship motion-affected comfort levels
The standard ISO 22834:2022 “Large yachts – quality assessment of life onboard – stabilization and seakeeping” provides a clear framework to evaluate and rate motion-affected comfort for a large yacht. The standard provides the process to compute a rating on a simple 5-star scale: the higher the number of stars, the higher the comfort onboard.
The standardized rating system also provides a way for naval architects to clearly show the impact on comfort level from changes in vessel design. For example, it shows the benefit of improved comfort between different VCG targets. It can be used to show the value of adding anti-roll technology to a yacht, too. The standardized 5-star scale gives a concise and clear way for a naval architect and vessel owner to understand and communicate about motion-affected comfort performance.
But the standard does not provide a tool that can be readily used during early stage design. What’s needed is software that both predicts ship motions and then quickly produces an ISO-compliant comfort rating so that design options can be evaluated. Naval architects can then give yacht owners the assurance they want on a comfortable design, using an accepted rating criteria.

The Ship Motion toolset brings ISO 22834 comfort evaluation capabilities to ProteusDS
These tools quickly calculate an ISO compliant motion-affected comfort rating based on yacht and stabilizer design.
Features and benefits

Calculate an ISO 22834 large yacht motion-affected comfort rating. The ISO standard details a specific way to quantify large yacht comfort involving multiple speeds and many sea state conditions. Calculate the ISO-compliant comfort rating using a purpose-built application in one step.
Instant calculation of ship performance metrics. Waiting for feedback on design changes slows down innovation. Rapid calculations speeds up innovation and reduces design costs. The purpose-built application computes ISO comfort rating instantly.
Calculate ISO comfort rating at any area on the vessel. Acceleration is the primary factor in establishing the effects on crew and equipment. But ship motion can result in complex changes in acceleration through the entire hull. Verify comfort rating at any location on the ship.
Make fundamental design decisions guided by ISO comfort rating. The yacht VCG can strongly affect motion-affected comfort. Get feedback on comfort rating to inform early-stage design decisions on placement of heavy equipment or aluminum superstructure as early as possible.

What’s inside?

Use an RAO computed by the ProteusDS ShipMo3D toolset as input to the comfort rating application. Generate motion RAOs for ship configurations like varying VCG, bilge keels, or fin stabilizers to compare the changes in comfort rating.

Specify minimum five locations relative to aft and baseline to evaluate comfort including the default Owner’s Cabin, Dining Area, Wheel House, Crew Area, and Beach Club.

ISO-compliant overall comfort rating is calculated for each area, at each speed, with an overall rating.

View Motion Sickness Incidence (MSI) values for each area across all sea states, at 0 kn and 12 kn speeds.

View Effective Gravity Angle (EGA) values for each area across all sea states, at 0 kn and 12 kn speeds.
Comprehensive summary view with notes, input areas, and all results for easy comparison of ISO comfort ratings.


Validated
at full scale

Ship motion software needs concrete validation to be trusted. ProteusDS has been validated with full scale ship motion data collected at sea. The data from this is used to validate new versions of the Ship Motion toolset on an ongoing basis.
Calculate ISO 22834-compliant comfort rating
Use vessel RAO as input
Review MSI and EGA values at each location
Make comparisons of comfort rating from anti-roll technologies, changes in VCG, hull form, and other parameters affecting RAO
Flexible software use on multiple computers
Access
FAQ

Can I provide RAOs in different formats?
Currently, the comfort rating application reads a motion RAO provided in the format computed by the ProteusDS ShipMo3D toolset. This file format is in human readable text, so you can use this to inform how to adapt your own RAO data if needed.
Do you offer software training?
Yes, and you have several choices. Use free online and video tutorials combined with live webmeetings to learn elements of the software. A self-guided training option is also available. Work with DSA Ocean engineers through paid support options to accelerate learning and completing a project.
Do I need an engineering degree to use this software?
Basic ship motion analysis is possible with a technical background. For more complex designs and unique applications, it helps to have an engineering background when you need to get into the details.
How do I get help on using the software?
Check out our variety of online and video tutorials here and here. Contact us for questions on software usage at support@dsaocean.com. If you need help with a specific design project, we can create a quote for paid training or consulting services to help you on your way.
Get a free demo to evaluate ISO comfort rating for your yacht design

Apply 7 day fully functional demo of the paid version of ProteusDS and the Ship Motion toolset. You can use this to learn the software and evaluate how it works to compute a comfort rating for your vessel.
Request a demoWhat’s different about
ProteusDS?

When you are lost, a GPS is worth a lot to get you back on track. If you are working alone on a mooring design, it’s easy to feel lost. You can feel lost if you are working with a new mooring design you don’t have experience with. Or you can feel uncertain if you are facing an exposed mooring location with extreme environmental conditions like high speed ocean currents or waves.
When you are working with ProteusDS, you always have someone to ask for ideas and help. We work with mooring designers around the world and are experts in working with our software. If you are feeling lost, we are here to help give you ideas and find a way to take the next step in your design process.
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