In the field of steel structure welding robots, laser vision positioning and arc sensor positioning are the two most widely used technologies in welding robot workstations. Each focuses on its principles, performance, and applicable scenarios, and together they support the precise implementation of welding automation.
Laser vision positioning technology is based on optical measurement. A laser emitter projects structured light onto the workpiece surface, and a high-definition camera captures the weld contour image formed by the reflected light. This image is then analyzed by an algorithm to generate 3D coordinate data. Its advantage lies in its non-contact measurement, which avoids sensor interference from weld spatter and high temperatures. This makes it particularly suitable for robotic welding workstations to locate complex welds, such as T-joints and groove welds. In thick steel plate welding, laser vision can accurately identify weld deviations as small as 0.1 mm. However, it is sensitive to workpiece surface finish. Rust or scale may increase image noise, necessitating the use of preprocessing algorithms to optimize the data.
Arc sensing positioning technology relies on changes in arc characteristics during the welding process, inferring the relative position of the welding torch and weld seam by real-time monitoring of arc voltage and current fluctuations. Its core advantage is its high real-time performance, with a response speed of up to milliseconds, enabling dynamic tracking of weld seam deviations caused by thermal deformation during welding. This technology has low requirements for workpiece surface condition and operates stably even in the presence of oil, dirt, or oxide layers. However, positioning accuracy is significantly affected by arc stability, and errors can increase to over 0.5 mm in high-current welding scenarios.
In practical applications, laser vision positioning is more suitable for high-precision, complex structural welding tasks, such as irregular welds on bridge steel components. Arc sensing positioning offers greater cost advantages for mass-produced, standardized workpiece welding, such as straight seam welding on factory steel structures. The two are not mutually exclusive. In high-end manufacturing scenarios such as large pressure vessels, a combined solution of "laser pre-positioning + real-time arc correction" is often used, balancing precision and stability, driving steel structure welding towards higher efficiency and lower defect rates.
As a professional steel structure welding equipment manufacturer, Xizhang Welding Robot is committed to providing professional robotic welding solutions and high-quality technical services to businesses, helping them grow. Companies with specific needs are welcome to contact us. Email: info@xzwelding.com