Introduction to Robot Vision Guided Positioning

Ⅰ. The applications of machine vision

The application of machine vision is mainly divided into four categories, including guidance, identification, gauging and inspection.

Ⅱ. The guiding part of machine vision applications

1. Preparatory work before machine vision application

Essentially, a machine vision system is to guide robots, measure items, count items, read barcodes, letters and numbers, and detect defects in an industrial environment. In any machine vision application, whether it is the simplest assembly inspection or a complex 3D robotic box picking application, the first step is usually to use pattern matching technology to locate objects or features of interest in the camera's field of view. The positioning of objects of interest often determines the success or failure of machine vision applications. So the preparation work before machine vision application is very important.

2. The challenge of component positioning

Component positioning is a very critical first step before machine vision applications. If the pattern matching software tool cannot accurately locate the components in the image, then it will not be able to guide, identify, inspect, count, or measure the components. Although component positioning sounds simple, in the actual production environment, the difference in component appearance can make this step very challenging. Appearance changes due to lighting or occlusion may make component positioning difficult. Although the machine vision system is trained to recognize components based on patterns, even the most strictly controlled process allows certain changes in component appearance. The effect of component presentation or posture distortion may also make component positioning difficult. To achieve accurate, reliable, and repeatable results, the component positioning tool of the machine vision system must be intelligent enough to quickly and accurately compare the training pattern with the actual items moved on the production line.

3. What is guidance?

Guidance is the use of machine vision to report the position and orientation of components. There may be many reasons for booting. First, the machine vision system can locate the position and orientation of the component, compare the component with the specified tolerances, and ensure that the component is at the correct angle to verify that the component is assembled correctly.

Then, the guidance can be used to report the position and orientation of the component in 2D or 3D space to the robot or machine controller, allowing the robot to position the component or machine in order to align the component. Machine vision guidance can achieve much higher speed and accuracy than manual positioning in many tasks, such as placing components on pallets or picking components from pallets; packaging components on conveyor belts; positioning and aligning the components to assemble them with other parts; place the component on the work shelf, or remove the component from the box.

4. The role and function of guidance

Guidance can also be used to align with other machine vision tools, which is a very powerful function of machine vision.

Because in the production process, components may be presented to the camera in an unknown direction. By positioning the component and aligning other machine vision tools with the component, machine vision can realize automatic tool positioning.