Flexible Intelligent Door Assembly Line of Changan Mazda Automobile Co., Ltd.

© Risong Technology

This case promotes the intelligent development of the automotive industry, ensures a sustainable consumption and production mode, and promotes inclusive and sustainable industrial development by innovating manufacturing technology.

The body-in-white door/hood/lid production line is the production line with the most challenging automatic integration in the automotive field. This time, Risong Technology launched the leading automatic, intelligent and flexible door/hood/lid production line and took the lead in mass production. Adopting all-round high-tech automation schemes—"Intelligent Visual Guidance Technology", "Intelligent Tightening Technology" and "Intelligent Quality Control Technology", with many core technologies reaching the international advanced level, the assembly line belongs to the model line case of intelligent manufacturing industry.

The production line includes processes such as automatic grabbing from the EMS line in the air, automatic calibration, gap measurement, visual guidance, automatic tightening assembly, quality monitoring, and torque monitoring, and deeply integrates intelligent elements such as laser and binocular vision, automatic tightening system, information monitoring system, flexible NC, high-speed conveying, and intelligent IoT. The entire line is fully automated by NC fixtures, and the shuttle system is used for body conveying, thus realizing the automatic assembly for the four doors, engine hood, trunk lid, and rear bumper in the takt time of 54 second/unit, automatic tightening of 64 screws, 4-second station conveying, and mixed line production for 8 models, with an annual production capacity of 200,000 units. It is of innovative and advanced significance to have achieved a high automation rate, high production efficiency, high production quality and high flexibility of automatic assembly.

Ultra-high-speed conveying technology assists high-efficiency assembly in 54 seconds/unit

It is difficult for people to travel at high speed under extreme load, but robots can do so with the help of technology.

Risong Technology applied the self-developed ultra-high-speed conveying technology to the assembly and adjustment line of the door/hood lid of the vehicle body, and adopted the reciprocating circular conveying device; through the developed two forms of lifting in the middle of the body and lifting the doorsills on both sides, and through the auxiliary motion control unit cooperating with the multiservo drive system, the assembly and adjustment line has achieved high-speed and accurate conveying, and created a record of conveying among 18 work items of the body in white in 4 seconds! The assembly line not only ensures the stable conveying, but also has the advantages of adapting to multi-model production and occupying a small space, which greatly improves the production efficiency! The entire line is able to complete the intelligent assembly of the four doors, engine hood, and trunk lid for one unit of vehicle in 54 seconds.

Mixed line production for 8 models satisfied the challenging customization requirements

In the era of high-speed operation and constant change, people's pursuit of vehicle models is also changing with each passing day, and the demand for high elasticity, flexibility and customization of automotive manufacturing becomes inevitable. The NC flexible positioning system developed by Risong Technology enables the assembly line to realize the collinear production of any vehicle model, random mixing and seamless switching in the production process. The assembly and adjustment line is provided with more than 230 sets of flexible NC positioning systems, which are capable of seamlessly positioning and grabbing the body chassis and door/hood/lid of each vehicle model, thus realizing fully automatic and random switching, satisfying the requirement of random mixed collinear production for 8 vehicles, and realizing the maximum production efficiency in the minimum space.

The flexible mixed production for 8 models is a big challenge for the assembly and adjustment line. The mass production in the door/hood/lid area needs to be matched with the mixed production in the assembly line exactly item by item. In the project, through nearly 100 logic programs in each location, with the help of vehicle type identification and vehicle type information conveyed by MES, each door is intelligently and automatically matched and then conveyed to the assembly line, thus realizing the intelligent system. The flexible technology can be controlled independently, so that automotive manufacturers can easily adjust the takt time, production models, etc., achieve high flexibility and high customization, and reduce production costs such as the costs in updating automotive manufacturing devices and upgrading personnel skills.

3D vision technology realizes efficient machine intelligence

While human visual recognition is limited, machine vision can be accurate and precise. In unmanned intelligent manufacturing, machine vision plays a major part in ensuring that the production quality reaches the standard. The assembly and adjustment line consists of 4 sets of vision systems, and the 3D laser vision accuracy is as high as 0.1 mm. The vision guidance technology sends the deviation value to the robot controller after the accurate comparison of the measured images with calculation, automatically corrects and compensates the robot's motion trajectory, and guides the robot to the accurate actual working position, thus realizing the accurate grabbing and positioning of the mounting holes of the vehicle body, the door and the door hinge, and the accurate measurement and assembly of the door frame of the vehicle body. The machine vision intelligent assembly technology developed by Risong Technology has the characteristics of a large measuring range, good flexibility, and high precision; it can realize automatic assembly with a high automation rate, high production efficiency, high production quality, and high flexibility.

The "quality door system" becomes a model of intelligent IoT to achieve the optimal production quality

In terms of quality control, the "quality door system" introduced along with the assembly and adjustment line is a model of intelligent IoT. The system collects all quality information of the entire production line and sends it to the cloud platform to form a complete data feedback and monitoring database. By comparing and analyzing the fluctuation through big data, the assembly quality of each vehicle body can be traced at any time, and the information of each production cycle can be monitored, thus forming a complete closed-loop production line system from automatic production to quality monitoring and feedback. Furthermore, the defect removal and process optimization are completed, which ultimately improves the automotive manufacturing quality and increases the manufacturing efficiency, while effectively avoiding the possible loss due to device failure.

Contributions to UN's Sustainable Development Goals

In this case, through innovative and advanced manufacturing technologies, it promotes the intelligent development of the automotive industry, ensures sustainable consumption and production patterns, and promotes inclusive and sustainable industrial development. It also further strengthens the implementation methods of sustainable development and activates the global partnership for sustainable development through technological innovation and global promotion and popularization of new production technologies. It complies with Articles 9, 12 and 17 of Sustainable Development Goals.