Wireless 3D Scanning for Bus Frame Quality Control

Volvo Buses is one of the world's leading providers of sustainable public transport systems including luxury fleet buses. Renowned for engineering innovation, passenger comfort, and road safety, Volvo operates a cutting-edge production facility in Hoskote, Bangalore. The brand is synonymous with reliability and continues to set industry benchmarks through the integration of advanced manufacturing technologies.

Streamlining Bus Frame Quality Inspection with 3D Scanning

Volvo Buses India faced persistent challenges during the tube assembly stage of bus frame manufacturing. The primary concern was the inability to implement a consistent and accurate quality inspection method due to the complexity and sheer scale of the bus frame. Traditional quality checks were limited and lacked precision.

To overcome these issues, Volvo sought a digital 3D scanning solution that could accurately assess build quality though selected minimum check point. The goal was to create a repeatable, data-driven inspection plan for enhanced structural integrity and production consistency.

Large-Scale Bus Frame Scanning

The object scanned was a full-sized bus frame made from non-machined square tubes. With dimensions of 15,000 mm (length) × 2,500 mm (width) × 3,400 mm (height), the frame presented unique challenges due to its size, geometry, and mixed material finishes, including shiny surfaces. These reflective materials typically require scanning spray, which adds time and complexity.

NimbleTrack Wireless 3D Measurement Scanner

To meet the technical demands of this project, SCANTECH's NimbleTrack wireless 3D measurement scanner was deployed. Though originally engineered for small to medium parts, NimbleTrack proved highly adaptable in scanning the large-scale bus frame through strategic setup planning and segmentation.

Technical Execution and Requirements

The technical requirement for the project was to achieve high accuracy without using photogrammetry. The scanning process was divided into a large number of carefully planned setups to cover the full bus frame.

Step-by-Step Project Workflow

1. Preparation

The scanning team began by aligning the frame's Z-plane with the CAD model. The large frame was logically divided into a large number of scanning setups. Each setup was optimized to capture the maximum surface area possible within the 3D laser scanner's working range.

2. Scanning Process

Each frame section was scanned using the NimbleTrack 3D measurement scanner. Successive scans were aligned using super-suspension matching technology, ensuring seamless data stitching and uniform accuracy throughout. NimbleTrack maintained a volumetric accuracy of 0.025 mm—critical for ensuring structural integrity in assembly.

3. Post-Processing & Analysis

A complete STL file of the scanned bus frame was created. The scan data was then aligned with the original CAD model to perform PIST (Points in Specific Tolerance) analysis. This helped identify variances and supported the development of a precise quality control strategy.

4. Measurement Results

According to the latest MP (Method Plan) points for the scanned bus, the current structure achieved 55% PIST compliance. This data has become foundational in driving continuous quality improvements.

5. Further Enhancements

Further enhancements are planned: an additional 50–60 measurement points are proposed to be added on the chassis and measured separately before assembly. This will allow for an even more detailed quality control approach during pre-assembly stages.

Benefits of SCANTECH's 3D Laser Scanner

Effortless Setup

With wireless capability and no warm-up or calibration needed, NimbleTrack allowed rapid deployment across multiple scan points.

Target-Free Operation

Consistent Data Accuracy

The system maintained high-resolution data capture even after a large number of setups.

Surface Versatility

Shiny and uneven surfaces were scanned directly without matting spray, reducing effort and improving efficiency.

Profile Measurement for Small Radius Features

Even subtle geometrical deviations were captured and matched accurately.

Fast Scanning Performance

Despite the bus frame's size, the entire project was completed in about 10 hours, allowing integration into Volvo's daily production workflow.

Validated, Repeatable Inspection Method

The system enabled a reliable quality control process that could be consistently applied across production batches. The streamlined workflow minimized deviations, leading to fewer defects and less time spent on corrections.

Advancing Manufacturing with Wireless 3D Laser Scanning

Volvo Buses India successfully implemented SCANTECH's NimbleTrack wireless 3D scanning solution to overcome complex quality assurance challenges in bus frame assembly. The system delivered a high-accuracy, efficient, and fully digital workflow that supported production consistency and reduced manual errors.

This project demonstrates the scalability and performance of NimbleTrack for large-scale industrial 3D scanning applications. Manufacturers in the automotive and commercial vehicle sectors can benefit from adopting this next-generation wireless scanning technology to improve quality control, streamline operations, and embrace the future of smart manufacturing.