On the basis of studying a large number of relevant data at home and abroad, this paper makes an in-depth study on the structure of steering system and its parts. Parametric modeling of the steering gear is carried out, and the interface of the steering gear model base is established through VB. CATIA is redeveloped through out of process access to realize the link with the model base. Just change the parameters on the interface and the required model will be generated automatically. The main creative research achievements are as follows:
(1) The overall design scheme and overall frame structure of the automobile rack and pinion steering gear are planned, the system platform is reasonably selected, and the steering gear model can be established quickly and accurately.
(2) The parametric modeling and macro recording method in the modeling process of the automobile rack and pinion steering gear are further studied. The parametric modeling and macro recording of the parts of the automobile rack and pinion steering gear are carried out, which not only makes the parts of the automobile steering gear accurately and quickly designed, but also simplifies and facilitates the programming.
(3) According to the constraint relationship of automobile rack and pinion steering gear parts, the virtual assembly of automobile rack and pinion steering gear is carried out, the interference analysis and inspection of steering gear assembly are carried out, and the parts that do not meet the design requirements or assembly relationship are modified. Finally, the virtual assembly of products is realized.
(4) Choose the way of out of process access to carry out the secondary development of CATIA, use VB to establish the steering gear interface, record and modify the macro into VB code, and realize the link with the model library. The model will be generated automatically by changing the parameters, which shortens the design cycle.
Although the parametric design of automobile rack and pinion steering gear is carried out, and the secondary development of CATIA based on VB is applied in this paper. However, due to the limited personal ability and time limit, there are still many aspects to be improved in the parametric design of automotive rack and pinion steering gear:
(1) Through the secondary development of CATIA, this system only completes the parametric design of automobile rack and pinion steering gear, and can further realize the parametric design of other types of automobile steering systems through this method.
(2) In this paper, the strength analysis and motion simulation of the automobile rack and pinion steering gear are not carried out. In the next step, this aspect can be studied in order to enhance the reliability and completeness of the design of the automobile rack and pinion steering gear.