摘要:Based on the new rules of the 4th national college students’ engineering and comprehensive training ability competition, established three-dimensional model using software UG NX, designed a kind of “S” type carbon-free,it can adapt to various poles’ distance and easy assembling and debugging.Focus on variable pitch mechanism and steering mechanism’s designing, and by motion simulation verify its rationality, the simulation analysis showed the car trajectory accords with a requirement. Finally,processed parts,assembled and debugged of the cars.Practice has proved that the design of the car conform to the requirements of the game, is reasonable, assembling outfit is convenient, easy to debug, can meet the requirements of a variety of stem from, smooth finish and get good grades.