3D Scanning: I Can See It, but How Do I Measure It?

Sometimes it can be a challenge to get the measurement you need from an existing part. The part may not have any consistent geometry to get a reference from or the part may be installed in an area where physical measurement tools are impractical. These kinds of situation can be an excellent place for 3D optical scanners to help improve your workflow.

In this case, the drive shaft alignment on a vehicle needs to be measured after a suspension lift was installed. If the transmission output and the rear differential are no longer aligned, substantial vibrations can be created when driving the vehicle at highway speeds. To get an acceptable alignment the vehicle needs to be under its own weight and located on reasonably level terrain to simulate typical driving stance.

This sounds like a simple procedure until we look at the transmission and differential. We can only see and reach very small sections of each shaft. So we cannot physically reference a tool to the shafts. We could hold an angle finder to either end. Though, neither piece has an exposed machined face that is aligned in a useful way with the output or pinion shafts. So, a measurement like that would be at best a guess. Alternatively, an externally referenced system like a probing arm could be used but without a purpose-built fixture physical measurement system are not practical either.

However, with Creaform’s Handy Scan Black Elite this angle can be quickly and easily measured directly from the visible shaft sections.

Within minutes the scanner can be deployed, the drive shaft can be scanned, and the angle can be measured. With the scanners handheld form factor allows I can easily maneuver under the vehicle to collect the scan. While, VXScan’s live mesh generation shows me exactly what data I have collected.

With the VXelements software, the small exposed sections on the pinion and output shaft are enough to get an accurate measurement. We find that the two shafts are aligned within 1 degree of each other. Well within the safe operating range for this project.

Creaform scanners are portable but powerful products to help you analyze physical objects.They can be deployed in areas that physical measurement systems are impractical or impossible to implement, they can provide useful data from area that hand tools cannot be used, and can allow for a deeper quantitative understanding of systems.

Collin Manchester
Application Engineer, Manufacturing Solutions
Computer Aided Technology, LLC