What are the steps in the design of automotive inspection tools? Let me tell you one by one.

1. Design modeling of workpieces and automotive inspection fixtures-automotive inspection fixtures must first analyze the workpieces with reference to the drawings of the parts, preliminarily draw up the inspection fixture design plan, determine the reference surface, concave and convex conditions of the inspection fixture, detect cross-sections, positioning surfaces, etc., and simply draw Its two-dimensional schematic diagram.

In the design of automobile inspection tools, what are the maintenance methods for standard parts of automobile inspection tools? The specific design modeling of inspection is the key, which directly affects whether the inspection tool can accurately inspect the quality of the workpiece.

Due to the characteristic of body panels that are mainly free-form surfaces, "reverse seeking from real objects" is the current general method of modeling. Reverse seeking is a method of constructing a prototype model with a specific shape and structure based on the existing workpiece or physical prototype, using a laser scanner to collect data, and through data processing, three-dimensional reconstruction and other processes. We use a laser scanner to scan the standard workpiece surface, collect the surface feature information mainly based on point clouds, convert the point coordinates to the car body coordinates, and use the surfacer software to process the point information to obtain the characteristic curve of the surface of the workpiece. , So as to generate the final free-form surface model; at the same time, the generated prototype model can be detected by the distance between the point cloud and the surface. It should be noted that the model obtained at this time is a sheet model with no thickness. It is necessary to distinguish the model as the inner or outer surface of the workpiece according to the surface scanned by the scanner, which is particularly important for the detailed design of the inspection.

Realize the inspection of the free-form surface of the workpiece by the inspection tool. Generally, the inspected surface and the inner surface of the workpiece maintain a constant gap of 3 or 5mm. The CNC machining machine tool can meet the higher precision requirements according to the designed surface digital model, and pass the actual inspection. The surface of the inspection tool can be combined with the special measuring tool to move back and forth to measure the deviation of the surface of the workpiece. There are two main methods for detecting the outer contour of the workpiece. When designing the corresponding inspection tool: ①The inspection surface extends about 20mm tangentially outward along the outer contour of the workpiece; ②Extends about 20mm downward along the normal direction of the outer contour of the workpiece. In general CAD software (such as UG), offset the workpiece surface inward by 3 or 5mm (if the generated workpiece model is the outer surface, add the thickness of the workpiece when making the offset), and then move the surface along The tangential or normal extension of the contour is 20mm to obtain the inspection surface of the inspection body, and then stretch a certain distance to the reference plane to be the inspection body model. Due to the complexity of the car body cover, a combination of the above two methods is often required when generating the inspection surface. However, for some special profiles, this is still difficult to achieve. Figure 2 shows a schematic diagram of the processing of complex shapes. In the figure, the surface of the workpiece of the engine support is obviously self-intersecting and interfering at the first and second places. In order to ensure that the main contour of the workpiece is detected, the detection at the corners with the vertical height difference is sacrificed to generate the inspection as shown in the figure. For the specific surface, finally double scribe lines along the contour of the workpiece and the interval of 3mm on the surface of the inspected concrete to facilitate the detection of the contour of the workpiece. Of course, many similar problems will be encountered in the design of the inspection tool (especially the inspection equipment), and post-processing of the infiltration understanding and experience of the inspection tool principle is required.