AI-Powered Drawing Verification System

Automatically checking structurally critical areas of LRV construction

POINT

  • Eliminating losses in cost and schedule caused by drawing errors

    System overview

    Checking construction drawings is a time-consuming task, and missed errors can result in the need to re-fabricate components—leading to significant cost increases and schedule delays. To address this, Obayashi has developed a system that automatically checks the coverage of structural drawings for precast (PCa) components used in the LRV construction method.
    The system supports drawing data in DWG (DXF) and PDF formats.
    As a web-based application, it can be accessed from anywhere with a network connection, username, and password. Check results are displayed in a summary outside the drawing frame, with flagged areas highlighted in color for easy review. Each drawing can be checked in about five seconds.

  • Extracting checklist items using AI

    AI-powered checklist extraction workflow

    Checklist items are extracted through the following steps:
    1. Drawing segmentation AI
    Identifies and extracts the type of drawing (e.g., shape drawings, rebar drawings), component names (e.g., columns, beams, joints), and sectional views (e.g., plan views, elevation views).

    2. Checklist extraction AI (Using generative AI and attribute estimation AI)
    Extracts checklist items—such as the number and spacing of main and shear reinforcement bars, and concrete cover thickness—from the identified drawings.
    Two types of AI are currently under development, with plans to adopt the one with higher accuracy in the future.

    2-1: Information extraction using generative AI
    By inputting images, vector data, and prompts, the generative AI extracts checklist items based on the specified dimensions in the drawing.

    2-2: Attribute estimation AI
    By inputting images, the AI estimates the attributes of circles and lines (e.g., main reinforcement bars, joint indicators) to extract checklist items.

  • Verifying extracted checklist items

    Extraction process of checklist items

    The checklist items extracted by AI are cross-checked against information from pre-registered structural drawings—such as section lists, column/beam layout guides, framing diagrams, and special specifications—to determine their accuracy.

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