Cassini

Statistical Process Control

Control charts, not contracts.

A complete SPC platform you deploy on your own infrastructure. Variable, attribute, and short-run charts. Nelson rules, capability analysis, MQTT / Sparkplug B ingestion, and a 300-endpoint REST API — all in one open-core package. Own your quality data. No vendor lock-in. No per-seat pricing traps.

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10+

Chart Types

Nelson Rules

300+

API Endpoints

200K

Samples / Min

SPC Engine

Every chart type. Every rule. No compromises.

Cassini ships a complete SPC engine — not a subset, not a starter kit. If your quality standard references it, Cassini supports it out of the box.

Variable Charts

X-bar & R, X-bar & S, Individuals & Moving Range for continuous measurement data. Plus CUSUM and EWMA for detecting small, sustained shifts that Shewhart charts miss.

Real-time via WebSocket

Attribute Charts

p, np, c, and u charts for defective/defect count data. Includes Laney p' and u' corrections for overdispersed data — the kind most SPC tools silently get wrong.

Overdispersion-corrected

Short-Run Charts

Deviation mode and Z-score standardization for low-volume and high-mix production. Chart multiple part numbers on a single control chart without waiting for 25 subgroups.

High-mix / low-volume ready

Nelson Rules

All 8 Nelson Rules, individually configurable per chart. Pro edition adds preset management with Nelson, AIAG, WECO, and Wheeler rule sets for standardized configuration across your plant.

8 rules, individually configurable

Capability Analysis

Cp, Cpk, Pp, Ppk, and Cpm indices included in Open. Pro edition adds non-normal distribution fitting with Box-Cox transformation and 6 distribution families for data that isn't normally distributed.

Non-normal fitting: Pro

Equipment Hierarchy

ISA-95 compliant structure: Enterprise, Site, Area, Line, Cell, Equipment. Organize charts, data, and permissions the way your plant actually operates — not the way a SaaS vendor decided to model it.

ISA-95 compliant

Cassini SPC dashboard showing an Individuals control chart with Nelson rule violation detection, control limits, and spec limits

Control chart dashboard with real-time violation detection

Cassini data entry screen with manual measurement input, spec limit validation, and batch tracking

Manual data entry with validation

Cassini violations list showing Nelson rule violations with severity, status, and acknowledgement workflow

Violation tracking and acknowledgement

Computation Transparency

“Show Your Work”

Click any calculated value — a control limit, a capability index, a Nelson rule violation — and Cassini shows you exactly how it was computed. Step-by-step. With the formula rendered in KaTeX and citations to the relevant AIAG standard.

No more black-box SPC. When an auditor asks how your Cpk was calculated, you don't open a support ticket. You click the number.

This is the feature quality engineers wish every SPC tool had. Cassini is the one that actually built it.

Upper Control Limit24.7832

UCL = X̄ + A₂ · R̄

X̄ = 23.4150

A₂ = 0.577 (n=5, AIAG Table VI-1)

R̄ = 2.3714

= 23.4150 + 0.577 × 2.3714

= 24.7832

Data Integration

Connect any data source.

From manual calipers to fully automated production lines, Cassini ingests data however it arrives.

MQTT / Sparkplug B

Subscribe to industrial IoT brokers and ingest measurement data in real time. Native Sparkplug B payload decoding for direct PLC integration. Open includes one broker; Pro unlocks unlimited.

OPC-UAPRO

OPC-UA server management. Browse nodes, configure subscriptions, and map tags to SPC characteristics — all from the browser. Available with Pro license.

Gage BridgeENTERPRISE

RS-232 and USB serial connections to handheld gages, micrometers, and CMMs. Press the button on the gage, see it on the chart.

CSV / Excel Import

Guided import wizard with column mapping, validation rules, and preview. Migrate historical data or import batch records without writing code.

REST API

300+ endpoints covering every entity in the system. Build custom integrations, automate data collection, or feed Cassini from your MES, ERP, or LIMS.

Manual Entry

Touch-friendly data entry with input validation, spec limit enforcement, and operator prompts. Built for the factory floor, not the back office.

Cassini Connectivity Hub showing MQTT broker status, data flow pipeline from sources through ingestion to SPC engine, and server monitoring

Connectivity Hub with data flow pipeline monitoring

Infrastructure

Deploy anywhere. Your servers, your rules.

Cassini runs where your data lives — on-premise, in a private cloud, or on a Raspberry Pi bolted to a machine. No phone-home. No cloud dependency.

Docker

Single-command deployment. Production-ready container images with health checks and volume persistence.

Multi-Database

SQLite for single-site. PostgreSQL, MySQL, or MSSQL for enterprise scale. Swap with a config change.

PWA + Offline

Install as a native app on any device. Full offline support for areas with unreliable connectivity.

Kiosk + Dashboard

Kiosk mode for factory floor terminals. Wall dashboard mode for control room displays. No mouse required.

Cassini kiosk mode showing a full-screen control chart with large navigation arrows, control limits, and real-time violation indicators

Kiosk mode — touch-friendly, full-screen SPC for the factory floor

Editions

Open · Pro · Enterprise

Open Edition is a full SPC platform — not a crippled demo. Pro adds production databases, multi-plant, and quality tooling. Enterprise adds compliance, advanced analytics, and dedicated support.