A V50 you can stand behind.
Probit Analysis Software is a focused desktop tool for one job done well: turning body-armour firing-session data into a sound V50 estimate, with the confidence limits and method checks you need to trust — and defend — the result.
What it's for
The probit method is the standard way to establish the V50 of body armour and ballistic protection — the impact velocity at which a projectile has a 50% probability of completely perforating the target. From a set of shots (impact velocity plus a complete- or partial-penetration result) the software fits the perforation model, estimates V50 and its standard deviation, derives the V1 and V99 velocities, and reports the confidence limits and firing-session conditions that make the result defensible. Method per NATO AEP-2920 (Edition A, Version 2), Annex H.
How it works
You enter your shot table — impact velocity and result, where CP is a complete penetration (perforated) and PP a partial penetration (stopped) — and the software does the rest: a maximum-likelihood fit, profile-likelihood confidence intervals on V50 and the standard deviation, the V1/V99 velocities, a PASS/FAIL check of the method's acceptance conditions, and an S-curve ready for a report. Everything runs locally on your Windows machine; your data stays with you.
Principles
- Correctness first. The calculation follows NATO AEP-2920 Annex H and is validated against the standard's published worked example.
- Focused, not bloated. One job, done properly, without a sprawling menu of things you'll never use.
- Your data is yours. A desktop app that works offline — nothing is uploaded anywhere.
Who makes it
Probit Analysis Software is an Arcane Systems product — an independent studio that builds and maintains its own small family of focused applications.
Have a question?
We're happy to help you decide whether it fits your testing.