3D Vision for Hair-Pin Motor Welding Points Measurement

For electric vehicles, or EVs, motors are key to building a powerful, comfortable, economical, and safe final product. Compared to traditional motors, hair-pin motors make better use of internal space and dissipate heat more efficiently. Consequently, they achieve higher power density and withstand higher operating temperatures. No wonder they are highly favored by manufacturers and take the center stage nowadays. However, the dense and shiny metal hairpins always confuse the vision system and output incorrectly, resulting in waste or low quality. But with the Sizector 3D Camera SX Series, inspecting a hair-pin motor becomes much easier and more stable. Let's explore how it works together.

Inspection Difficulties

High Number of Weld Points: Taking a six-layer hair-pin motor as an example, with 48 slots and an average of 3 welding points per slot, totaling 144 welding points.

Challenges in Imaging: Welding points are round tops of reflective metal, resulting in distortion when capturing outer welding points, leading to poor edge imaging and difficulties in quality assessment.

Multiple Inspection Tasks: Inspection tasks include location, profile tolerance measurement, and inspection of various welding defects for each welding point.

Sizector 3D Camera SX Series for hair-pin measurement and inspection

The Sizector® 3D camera SX series employs hardware computation imaging technology, multi-projection technology, and telecentric lenses. It utilizes area-array imaging and can simultaneously inspect multiple welding points, making it particularly suitable for quality inspection of welding points in hair-pin motors.

A clear view with 2D+3D results for hair-pin motor

One-stop 2D+3D Measurement

The Sizector® 3D camera SX series employs telecentric lenses to minimize edge distortion during capture, ensuring complete imaging of each welding point within the field of view. It can seamlessly integrates with external lighting, allowing the camera to synchronously control exposure. This setup simultaneously outputs both 2D grayscale images and 3D point cloud data, providing a one-stop, comprehensive solution for both 2D positional accuracy and 3D defect inspection.

Greyscale - 2D image

 Depth map - 2D+3D fusion results

High Image Signal-to-Noise Ratio (SNR) and Integrity

The Sizector® 3D camera SX series inherits Mega Phase's unique camera hardware HDR fusion technology, providing better imaging integrity for highly reflective materials and ensuring more stable and accurate 3D data. This ultimately helps users improve the accuracy of welding point quality inspection.

Checking different kinds of defects imultaneously with high precision

With an XY accuracy up to 0.0062mm, the Sizector® 3D Camera SX Series precisely captures the welding points' profile. This enables clear imaging of various defects such as misalignment, underfill, skips, sharp points, and welding spatter.