A prediction method for assembly surface contact considering form error

Form error deflects the assembly surfaces and thus greatly affects the assembly accuracy of precision mechanical systems. Based on rigid motion, this paper proposes a prediction method for assembly surface contact considering form error to improve the simulation accuracy of virtual assembly. The method estimates the assembly equilibrium state by simulating the realistic behaviour of surfaces in assembly process: Firstly, one surface is fixed and the other is transferred along the assembly direction until the first contact occurs. Then, the other surface is rotated according the assembly force and the previous contact positions to successively reach the second and third contacts. The rotation operation is repeated until the assembly equilibrium conditions are finally met. Particularly, a space slicing algorithm is put forward to achieve faster calculation of the rotation information including rotation axis, rotation direction and rotation angle. This method can be applied in the field of assembly simulation and assembly verification. At the end of this paper, an assembly case of two rectangular plates is carried out to prove the feasibility and effectiveness of the method.