Scan Obstructed and Complex Objects - NavVis MLX

Introduction

This document describes how to scan areas containing large machines (production equipment, cells, racks, or line segments) with NavVis MLX so they appear sharp, correctly positioned, and complete in your deliverables.

What Good Capture looks like

A well-captured scan of a machine has the following characteristics:

• Geometry accuracy (SLAM quality): Edges and small offsets appear crisp in NavVis IVION, without double edges, bending, or visible drift.

• Completeness: Important faces (including the rear where required) and connection points to floors/walls/adjacent assets are captured with coverage from multiple angles.

• Useful panoramas: Key labels and controls are readable, and the machine is colorized consistently from more than one side.

Best practices

1. Start with the general area, then move in

Scan the surrounding room or aisle first. This gives the NavVis MLX structural context before you move in close to the machine. The SLAM stays more stable when the fixed reference points are visible to the device, such as corners, wall intersections, door frames, columns, beams, ceiling grid lines, and strong floor markings.

• Walk in the aisle or open area around the machine.

• Keep corners, columns, or strong floor markings in view.

• Then move in toward the machine while still seeing some of this structure.

Note: Refrain from allowing the machine to fill the entire field of view for an extended duration, as this leads to the surroundings becoming obscured, which causes drift.

2. Keep motion smooth

Because the NavVis MLX is handheld, capture motion is driven by your hand and arm. To keep SLAM and panoramas stable:

• Walk at a slow, steady pace.

• Avoid fast arm swings or sudden changes of direction.

• Slow down before reaching the machine. Do not thrust the device toward it.

• Keep the device orientation generally stable and use gentle rotations.

Walk around the device twice

1. First Loop - Walk a wide path:

• Walk a wide path around the machine. Use as much space as you have.

2. Second Loop - Move closer than the previous loop:

• Walk around the machine again, but this time stay closer to it.

• Slow down when you pass cables, control boxes, or connection points.

• Take a small step to the side so the scanner can see the edges from a different angle.

Note: Stay at least 50 cm (0.5 m) from the machine. Anything closer is ignored by the scanner and won’t be captured. Getting closer does not improve quality and can cause panorama stitching errors (warped views or panoramas that don’t line up), and can also contribute to SLAM drift.

4. Scanning obstructed sides

Large machines are often blocked on one or more sides by walls, guarding, or adjacent equipment.

• Add short, targeted detours that expose the scanner to the obstructed side.

• Use diagonal paths where possible. Diagonals usually reveal more than parallel passes.

• If the rear matters, plan at least one path segment that gives the scanner a clear view of that angle (from another aisle, a gap between machines, or a corner of the cell).

Note: The handheld NavVis MLX allows easy access to tight corners and small openings. However, avoid putting the device into very small cavities. If the laser scanner only detects very close surfaces, SLAM will likely break.

• Keep structural references (corners, posts, floor lines) in view during these detours so SLAM stays stable.

• If you can’t physically reach the rear, capture from as many side angles as possible and document the limitation.

Capturing Panoramas

• Capture panoramas in the areas of the machine that people will need to view later (for example, operation, maintenance, safety, or asset identification):

  • Control panels and operator stations.

  • ID plates, serial numbers, warning labels.

  • Connection points and interfaces (for example, valves, hose connections, electrical cabinets).

• For readable text and numbers:

  • Stand still during capture. Avoid any hand movement or arm rotation around the moment of capture.

  • If a label is partially obstructed or especially important, capture an additional panorama from a second angle.

  • Use Manual capture mode when capturing large machines

• For colorization:

  • Capture panoramas on multiple sides of the machine, not just from one main aisle.

  • If access is limited on one side, add at least one panorama from the best available angle toward that side.

On-site validation (before leaving the scan area)

• Quality map

  • Check the quality map on the device UI. Aim for solid, bright blue coverage around the machine and the scan areas.

• Multi-angle coverage

  • Check that each important side of the machine was scanned from at least two different angles, especially any side that was blocked earlier.

• Panorama spot-check

  • Open a few panoramas that show the machine. Make sure labels and ID plates are readable and not motion-blurred, and that the machine is visible from more than one side.