This project belongs to the field of mechanical design. Against the background of overcapacity in my country's equipment manufacturing industry, the development of high-end mechanical products has become an inevitable trend. Products in various fields such as automobile parts, ocean engineering and port equipment, machine tools and robots, engineering machinery, and mining machinery are all facing technological innovation and product replacement. For a long time, the "stupid and crude" characteristics of my country's mechanical products have not only led to low international competitiveness of products, but have also become a technical threshold for further innovation and upgrading of products. Achieving the lightweighting of mechanical structures can not only reduce product costs, but also reduce the total installed power of equipment, change the driving form, and improve operating efficiency and operating performance. Therefore, structural lightweighting technology has become the key to the technological innovation and upgrading of my country's mechanical products, and it is a key technical bottleneck that must be broken through for the development of mechanical products towards high-end.
Since 2005, the project team has carried out key technical research on lightweight design of mechanical structures with the goal of realizing lightweight mechanical structures and further realizing the upgrading of mechanical products. With the support of multiple national, provincial and ministerial projects, through in-depth cooperation research between schools and enterprises, a number of key technologies for the lightweight design of mechanical structures have been invented. On the basis of realizing structural lightweight, key components of typical mechanical products have been invented. A number of innovative technologies have finally integrated and developed a number of innovative and upgraded mechanical products.

1. Adaptive growth technology for plate and shell structures: Aiming at the common lightweight design problems of plate and shell structures in mechanical products such as automobile parts and engineering ships, the adaptive growth technology for reinforcing ribs was invented [ZL201210213720.7, ZL201010154892.2].
2. Lightweight configuration design technology for box structures: For box structures in port cranes, machine tools and excavators, a lightweight configuration design technology for box structures was invented [ZL200910197135.0, ZL201010154882.9].
3. Comprehensive lightweight design technology for complex assembly structures: For complex assembly structures in mechanical products, a method for determining boundary conditions of complex assembly components and an adaptive material distribution method for three-dimensional structures were invented [ZL201210384639.5, ZL201110193932.9, ZL201110268853.x, ZL201110229100.8].
4. Innovative technologies and upgraded products for key components of typical mechanical products: On the basis of lightweight product structure, we have invented a number of innovative technologies for key parts and components of car seats, port equipment and other products, and integrated and developed a number of innovative products [ZL201210286936.6, ZL200910199483.1, ZL201010526892.0, ZL201110027067.0, ZL201110045517.9, ZL201210208550.3，ZL200910260336.0，ZL201110229039.7】。
   It has used the key technologies invented to develop and complete a variety of upgraded products for 8 companies in the industries of car seats, port equipment and marine ships, machine tools and robots, engineering machinery, mining machinery, etc., realizing the innovation and upgrading of systematic technology and performance of the whole machine. Among them, the average weight loss of car seat frames is 15.4%, and the average weight loss of port equipment structural parts is 6%-15%. The innovative port equipment developed has been exported to Southeast Asia, the Middle East, Europe and other regions. In the past three years, the new output value of the unit has been 1.662 billion yuan and the new profit has been 196 million yuan; the new output value of the application unit has been 881 million yuan, and the new profit has exceeded 280 million yuan. The promotion and application of invention technology has broken through the threshold of further innovation and upgrading of mechanical equipment due to excessive structural weight, changed the traditional product development and design concept, and provided important technical support for the systematic innovation of my country's mechanical equipment.
   This project authorizes 16 invention patents, 16 utility model patents, and 2 software copyrights.