What to know before you rely on a result.

Our software tools calculate results from models. A result is an estimate. It depends on the inputs you give, the part and material data behind it, and the limits of the method used, and it may be wrong or out of date.

Nothing a tool produces is a design certificate, a class or regulatory approval, a safety case or professional advice. Where a tool compares a design with a rule, such as the IMO intact stability criteria or SOLAS, that comparison is a reference only. Before you rely on a result to build, buy, put equipment into service or sign off a design, or wherever people or property could be harmed, check it by independent means: by test, or by a suitably qualified engineer. This adds to section 06 of the Terms of Use.

Parts, materials and examples. Part libraries, material properties, preset hulls and sample projects come from datasheets, published sources and round example numbers. Datasheets change and we can misread one. Each part shows where its figures came from and when we last checked them. Check the manufacturer’s current datasheet before you buy or build. Sample projects use illustrative numbers.

Reports and exports. A PDF report or exported file shows the inputs and assumptions used at the time. It is not updated when a tool changes, and a report made during a trial carries a trial watermark.

Emrys ND (NavArch Designer). Hydrostatics and stability are computed from the hull form. Resistance uses Holtrop and Mennen for displacement ships, Savitsky for planing hulls and published methods for submerged bodies, with the DARPA SUBOFF hull checked against tow-tank data. Glider performance follows Merckelbach and others (2019), and propellers use the Wageningen B-series polynomials. Seakeeping uses a three-dimensional panel method in linear potential flow, checked against the open-source Capytaine code. Pressure-hull checks use thin-shell yield and buckling formulas, and hull compression uses exact thick-wall (Lamé) elasticity. Scantlings are first-pass checks, not class rules.

Emrys PD (Power Designer). Power budgets come from the loads, hours and efficiencies you enter. Converters are sized with standard topology equations and simulated, battery behaviour uses simplified models with temperature and ageing factors, and solar yield uses site climate data. Results are only as good as the part figures and assumptions you set.

Emrys MX (RF simulator). Antenna patterns and impedance come from closed-form designs and from thin-wire method-of-moments, cavity-model, transmission-line and planar solvers. The wire solver has been compared with NEC-2. Link budgets use free-space loss and published approximations for atmosphere, rain and terrain. Each solver has size and frequency limits, shown in the tool.

Each tool lists its method limits in the tool or on its Export tab, and in its PDF report. Validation notes for the methods are available on request through the contact page.

The tools are built with the open-source components below. Each remains the property of its authors and is used under its own licence. Licence texts are in the component’s files or on its project page.

If you think we have missed a credit or a licence condition, please tell us and we will correct it.

Terrain heights are approximate: they have vertical errors and do not show buildings or trees. Map layers are for orientation, not survey.

Where your browser connects. When you use a map, place search, terrain, solar-data or satellite feature, your browser contacts these services directly and sends the coordinates, place name or other details the request needs. Their own terms and privacy policies apply to that. See also our Privacy & Data page.

Part numbers, product names and logos shown in the tools are trademarks of their owners. We use them only to identify parts, and we are not affiliated with or endorsed by those owners.

Questions or corrections: info@emryssystems.com or the contact page.