𓍝 Metri-Report

Smart OIML R-76 Statutory Testing & Legal Metrology Automation Platform

Measure • Validate • Verify • Report

_{SIH 2026 Prototype · Legal Metrology · Non-Automatic Weighing Instruments · OIML R-76}

⚖️ What is Metri-Report?

Metri-Report is a full-stack statutory testing and reporting platform designed for Non-Automatic Weighing Instruments (NAWI).

The platform digitizes the workflow from:

Instrument Registration → Test Configuration → Observation Entry → OIML Calculation → Compliance Evaluation → Evidence Sealing → Review → PDF/DOCX Report → Finalization

The system is designed around OIML Recommendation R 76-1:2006 (E) and the Legal Metrology (General) Rules, 2011.

It brings statutory testing, metrological calculations, evidence management, role-based workflows and report generation into one unified platform.

🏛️ Smart India Hackathon 2026

🇮🇳 Legal Metrology Automation · Metri-Report

Field	Details
Organization	Department of Consumer Affairs, Ministry of Consumer Affairs, Food & Public Distribution, Government of India
Problem Statement	Development of a Software Program/Application for Generation of Test Reports for Non-Automatic Weighing Instruments (NAWI) as per OIML Recommendation R-76
Domain	Legal Metrology
Standard	OIML R 76-1:2006 (E)
Instrument Type	Non-Automatic Weighing Instruments (NAWI)
Project	Metri-Report
Status	SIH 2026 Prototype

📑 Project Presentation

🏆 Metri-Report · Smart India Hackathon 2026

📖 Navigate Presentation

_{Use Previous and Next to navigate the presentation,
or open the complete PPT directly in Google Drive.}

🌐 Live Prototype

🚀 Interactive Metri-Report Platform

_{Click the preview or button above to open the live Metri-Report prototype.}

🎥 Project Videos

🎬 Watch Metri-Report in Action

🎞️ Short Explanation

_{Quick overview of the problem, solution and platform.}

🖥️ Prototype Demo

_{Walkthrough of the working Metri-Report prototype.}

🧩 The Problem

Traditional statutory weighing-instrument testing involves multiple disconnected activities:

Manual instrument registration
Manual test configuration
Physical observation recording
Repeated metrological calculations
Manual compliance interpretation
Evidence handling
Review and approval
Preparation of statutory reports
Maintaining audit history

This creates a workflow where data, calculations, evidence and reports can become fragmented across different systems or manual records.

Metri-Report brings these activities into one structured digital workflow.

🔄 From Manual Testing → Digital Statutory Workflow

🧾

REGISTER

_{Instrument

Specifications

Manufacturer}

→

🧪

TEST

_{Conditions

Observations

Applicable Tests}

→

🧮

CALCULATE

_{MPE

Turning Point

Error Analysis}

→

📋

REPORT

_{PDF

DOCX

Compliance}

🔐

EVIDENCE

_{SHA-256

Photos

Test Artifacts}

👥

REVIEW

_{RBAC

Approval

Technical Review}

🧾

AUDIT

_{Events

Timestamps

Immutable Logs}

🔒

FINALIZE

_{Report Lock

Versioning

Integrity}

💡 Problem → Solution

Challenge	Metri-Report Solution
📄 Manual report preparation	Automated PDF & DOCX report generation
🧮 Repetitive calculations	Automated OIML calculation engine
⚖️ Complex metrological rules	Versioned OIML rule engine
🔍 Difficult traceability	Clause-level result explainability
📷 Scattered evidence	Centralized evidence vault
🔐 Evidence integrity concerns	SHA-256 cryptographic hashing
👥 Multiple user responsibilities	Role-Based Access Control
📝 Manual review workflow	Digital review and approval workflow
🕒 Limited audit visibility	Immutable chronological audit trail
📚 Changing standards	Versioned statutory rule architecture

✨ Core Capabilities

⚖️ METROLOGY	🧮 CALCULATION	🔐 INTEGRITY	📄 REPORTING
NAWI Testing	MPE Calculation	SHA-256 Hashing	PDF Generation
OIML R-76 Rules	Turning Points	Evidence Vault	DOCX Generation
Accuracy Classes	Error Analysis	Audit Trail	Report Versioning
Verification Workflow	Compliance Logic	Immutable State	Statutory Format

🏗️ System Architecture

flowchart TD

    USER["👤 Legal Metrology Officer / Engineer"]

    UI["🖥️ Metri-Report Web Interface<br/>HTML + CSS + JavaScript + Three.js"]

    GATEWAY["⚙️ Node.js Gateway<br/>Port 3000"]

    API["🚀 FastAPI Backend<br/>Port 8000"]

    AUTH["🔐 Authentication & RBAC"]

    VALIDATION["✅ Validation Layer"]

    RULES["📚 OIML R-76<br/>Versioned Rule Engine"]

    CALC["🧮 Metrological<br/>Calculation Engine"]

    REPORT["📄 PDF / DOCX<br/>Report Engine"]

    EVIDENCE["🔒 Evidence Vault<br/>SHA-256"]

    AUDIT["📜 Audit Trail"]

    DB[("🗄️ SQLite / PostgreSQL")]

    STORAGE["📁 File Storage<br/>Evidence + Reports"]

    USER --> UI
    UI --> GATEWAY
    GATEWAY --> API

    API --> AUTH
    API --> VALIDATION
    API --> RULES
    API --> CALC
    API --> REPORT
    API --> EVIDENCE
    API --> AUDIT

    AUTH --> DB
    VALIDATION --> DB
    RULES --> DB
    CALC --> DB
    REPORT --> DB
    EVIDENCE --> DB
    AUDIT --> DB

    EVIDENCE --> STORAGE
    REPORT --> STORAGE

🔬 OIML R-76 Compliance Engine

Metri-Report is structured around OIML Recommendation R 76-1:2006 (E) and associated statutory testing requirements.

📐 Turning Point Calculation

The platform implements the changeover turning point calculation:

$$ P = I + 0.5e - \Delta L $$

Where:

P = calculated turning point
I = indicated value
e = verification scale interval
ΔL = additional load

📊 Error Calculation

$$ E = P - L $$

Corrected error:

$$ E_c = E - E_0 $$

Where:

E = error
L = applied load
E₀ = zero error
E_c = corrected error

📚 Statutory Rule Coverage

The platform organizes statutory requirements into a versioned rule system covering areas including:

Accuracy classes
Verification scale interval
Maximum Permissible Error
Turning point / changeover calculations
Zero error
Repeatability
Eccentricity
Creep
Discrimination
Tare
Influence factors
Evidence integrity
Report generation

The system is designed so that ambiguous or unconfigured requirements can be surfaced instead of silently producing unsupported results.

MANUAL REVIEW REQUIRED and NOT CONFIGURED states are used where applicable.

🧮 Calculation & Verification Pipeline

flowchart LR

    A["⚖️ Instrument<br/>Specifications"]

    B["🧪 Test<br/>Observations"]

    C["📚 Applicable<br/>OIML Rules"]

    D["🧮 Calculation<br/>Engine"]

    E["📊 Error + MPE<br/>Evaluation"]

    F{"Compliance<br/>Check"}

    G["🟢 PASS"]

    H["🔴 FAIL"]

    I["🟡 MANUAL REVIEW"]

    A --> D
    B --> D
    C --> D

    D --> E
    E --> F

    F -->|Within Limit| G
    F -->|Outside Limit| H
    F -->|Ambiguous / Missing| I

🧾 Statutory Testing Modules

Module	Purpose
🏠 Homepage	3D WebGL interface, navigation and platform overview
⚖️ Instrument Registry	Register NAWI instruments and metrological specifications
🧪 Evaluation Workspace	Execute the statutory evaluation workflow
📊 Report Archive	Store, verify and retrieve generated reports
🔐 Evidence & Vault	Store evidence and generate cryptographic hashes
👥 User Privileges & RBAC	Manage user roles and permissions
📜 Audit Trail Log	Inspect chronological system events
📚 OIML Rule Engine	Inspect and manage statutory rules
📖 Swagger API Docs	Explore backend REST APIs

🧪 Evaluation Workspace

The Evaluation Workspace provides a structured statutory testing workflow.

Typical workflow

Instrument
    ↓
Test Conditions
    ↓
Applicable Tests
    ↓
Observations
    ↓
Calculations
    ↓
Compliance
    ↓
Evidence
    ↓
Review
    ↓
Report Generation
    ↓
Finalization

The system supports:

Instrument specification entry
Environmental conditions
Applicable test selection
Observation entry
Metrological calculations
Compliance evaluation
Evidence upload
Reviewer observations
PDF/DOCX generation
Report finalization

🔐 Evidence & Cryptographic Integrity

Metri-Report includes an evidence workflow designed around cryptographic integrity.

Evidence lifecycle

flowchart LR

    A["📷 Test Evidence"]

    B["📁 Upload"]

    C["🔐 SHA-256"]

    D["🗄️ Evidence Vault"]

    E["📜 Audit Event"]

    F["🔒 Finalized Record"]

    A --> B
    B --> C
    C --> D
    D --> E
    E --> F

Evidence can include:

Calibration certificates
Test photographs
Raw testing artifacts
Supporting documents
Other statutory evidence

The generated cryptographic digest can be used to detect unexpected evidence modification.

👥 Role-Based Access Control

Metri-Report uses role-based access control for different statutory responsibilities.

Role	Primary Responsibility
ADMIN	Administration, roles, configuration and finalization
LAB_MANAGER	Instrument management, test assignment and workflow approval
TEST_ENGINEER	Test execution, observations and evidence
REVIEWER	Calculation review and technical approval
VIEWER	Read-only access to repository and audit information

📄 Automated Report Generation

Metri-Report provides automated generation of:

PDF

Structured statutory test report
Metrological tables
Compliance results
Testing information
Evidence references
Disclaimers

DOCX

Editable evaluation package
Structured laboratory record
Test information
Calculation results
Review information

The report engine is based on:

ReportLab
python-docx

📜 Audit Trail

The Audit Trail provides chronological visibility into system activity.

Captured information can include:

Event type
Timestamp
User
Action
Test/report context
Event payload
Related system state

This supports traceability across the evaluation lifecycle.

🗂️ Project Structure

MetriReport/
│
├── backend/
│   ├── app/
│   │   ├── api/
│   │   ├── calculations/
│   │   ├── compliance/
│   │   ├── core/
│   │   ├── models/
│   │   ├── reports/
│   │   ├── schemas/
│   │   ├── services/
│   │   └── tests/
│   │
│   └── requirements.txt
│
├── frontend/
│   ├── index.html
│   ├── evaluation-workspace/
│   ├── instrument-registry/
│   ├── report-archive/
│   ├── evidence-&-vault/
│   ├── user-privileges-&-rbac/
│   ├── audit-trail-log/
│   ├── OIML-Rule-Engine/
│   ├── server.js
│   ├── subpage-shell.css
│   ├── fonts/
│   └── assets/
│
├── docs/
│
└── README.md

🧱 Technology Stack

Layer	Technology
Frontend	HTML5, CSS3, JavaScript
3D / Graphics	Three.js, WebGL, GLTF
Frontend Gateway	Node.js
Backend	FastAPI
Language	Python
Validation	Pydantic
ORM	SQLAlchemy 2.0
Database	SQLite / PostgreSQL
Reports	ReportLab, python-docx
Security	JWT, Password Hashing
Integrity	SHA-256
Testing	Pytest
Deployment	Docker / Docker Compose
Prototype Hosting	Vercel

🚀 Getting Started

Prerequisites

Python 3.9+
Node.js 18+
npm
Git
Docker (optional)

Backend Setup

cd backend

python3 -m venv venv

source venv/bin/activate

pip install -r requirements.txt

PYTHONPATH=. uvicorn app.main:app --reload --port 8000

Backend:

http://localhost:8000

Swagger:

http://localhost:8000/docs

Frontend Setup

cd frontend

npm install

node server.js

Frontend:

http://localhost:3000

🧪 Run Automated Tests

Run the backend test suite:

cd backend

python3 -m pytest app/tests/ -v

The test suite covers areas such as:

Calculation logic
Boundary conditions
Compliance
Security
Report generation
Integration behavior

🐳 Docker Deployment

Build and start the complete stack:

docker compose up --build

Services:

Service	URL
Frontend	`http://localhost:3000`
Backend	`http://localhost:8000`
Swagger	`http://localhost:3000/docs`
Backend Swagger	`http://localhost:8000/docs`

🎬 SIH 2026 Demo Flow

A concise demonstration can follow this sequence:

01 · Login

Use one of the available demo roles.

02 · Dashboard

Inspect platform metrics and navigation.

03 · Instrument Registry

Select or create a NAWI instrument.

04 · Evaluation Workspace

Launch a statutory evaluation.

05 · Test Configuration

Configure conditions and applicable tests.

06 · Observations

Enter or load test observations.

07 · Calculations

Run the OIML calculation engine.

08 · Compliance

Review permissible limits, calculated values and status.

09 · Evidence

Upload supporting evidence and generate SHA-256 hashes.

10 · Review

Reviewer verifies calculations and observations.

11 · Report

Generate the PDF/DOCX evaluation report.

12 · Finalize

Finalize and lock the statutory record.

🧭 End-to-End Intelligence Flow

flowchart TD

    A["⚖️ Instrument"]

    B["🧪 Statutory Test"]

    C["📊 Observations"]

    D["🧮 OIML Calculation"]

    E["📋 Compliance"]

    F["🔐 Evidence"]

    G["👥 Review"]

    H["📄 PDF / DOCX"]

    I["🔒 Finalized Record"]

    A --> B
    B --> C
    C --> D
    D --> E
    E --> F
    F --> G
    G --> H
    H --> I

📱 Responsive UI / UX

Metri-Report includes responsive interface work for compact mobile viewports.

Mobile-focused improvements

Compact navigation
Responsive module layouts
Touch-friendly controls
Responsive evaluation forms
Mobile-friendly evidence upload
Horizontal scrolling for large statutory tables
Adaptive spacing and typography
Compact dashboard components

The frontend architecture is designed to preserve usability across desktop and mobile layouts.

🔒 Security & Integrity

Metri-Report incorporates several security-oriented mechanisms:

🔑 JWT authentication
👥 Role-Based Access Control
🔐 Password hashing
🌐 CORS controls
🧾 Audit logging
🔒 SHA-256 evidence hashing
🗄️ Controlled report storage
🔒 Finalized report immutability workflow
🧩 Environment-based configuration

Never commit production credentials, secrets, private keys or sensitive deployment configuration to the repository.

🧠 Design Philosophy

Measure → Validate → Explain → Report

⚖️

MEASURE

_{Capture statutory

test observations}

🧮

VALIDATE

_{Apply OIML rules

and calculations}

🔍

EXPLAIN

_{Expose values,

limits and references}

📄

REPORT

_{Generate structured

statutory documents}

🗺️ Roadmap

Metri-Report
│
├── ⚖️ Metrology
│   ├── Expanded statutory rule coverage
│   ├── Additional test workflows
│   └── Extended instrument support
│
├── 🧮 Calculation Engine
│   ├── More verification scenarios
│   ├── Extended boundary testing
│   └── Additional mathematical validation
│
├── 📄 Reporting
│   ├── More statutory report templates
│   ├── Enhanced report versioning
│   └── Digital verification workflows
│
├── 🔐 Integrity
│   ├── Stronger evidence lifecycle
│   ├── Advanced audit controls
│   └── Extended verification mechanisms
│
└── ☁️ Deployment
    ├── Production database support
    ├── Scalable storage
    └── Cloud deployment

⚠️ Legal Metrology Disclaimer

IMPORTANT NOTICE: Metri-Report is a prototype system developed for SIH 2026. It is intended to demonstrate digital automation of NAWI testing and report-generation workflows based on configured OIML R-76 requirements.

The prototype does not by itself constitute statutory Legal Metrology Model Approval, certification or gazette notification under applicable Indian law.

Actual statutory decisions, approvals and certifications remain subject to the competent authority, applicable legislation, notified rules, standards and authorized metrological procedures.

👨‍💻 Project