Ford uses 3D simulation imaging technology to inspect rear axle gears

    Ford is using a newly developed 3D mapping technology to analyze the rear axle components of Ford F-Series pickup trucks during the assembly process, with the goal of increasing the smoothness of the components and thus improving the driving experience for drivers.

    Similar to Google Earth, Ford's photogrammetric pattern reader (PPR) uses a pair of digital cameras to combine photos of the rear axle gears into a series of 3D images, and then compares the resulting images with the ideal model of the workpiece on the computer. Finally, the workpieces that do not meet the model standards after comparison are discarded to ensure the high quality and uniformity of the workpieces.

    This technology helps engineers and quality supervisors to more accurately distinguish the quality of workpieces. Errors that are usually indistinguishable by the naked eye can be concluded by comparing with PPR technology. Ford engineers pointed out that the company will use PPR technology extensively in the quality inspection of commercial vehicle workpieces in the future. At present, the technology is first used to inspect the rear axle gear transmission system.

    The PPR system uses side-by-side cameras and infrared lights to slice a series of two-dimensional images into a single three-dimensional image for analysis.

    The technology is currently being trialed at Ford's Sterling Axle Plant in Michigan, USA.

How it works

    The staggered gears used in the rear axle have very complex geometry and curvature characteristics, so a single photo cannot show both sides of the gear shaft. The PPR system uses two cameras to take 9,000 1024×1 pixel 2D photos of each tooth of the rear axle gear and combine the 2D photos into a complete 3D photo.

    The 3D photo is compared with the computer model. If the rear axle gear error exceeds a certain limit, it is considered a defective product. Generally speaking, about 2 to 5 parts out of 1,000 parts do not meet the standards. When the defective rear axle gear is installed on the car, it will increase the running noise and affect the durability of the workpiece.