Using the CATIA DMU motion simulation module to analyze the motion characteristics of the six-link h

Abstract:

The CATIA DMU motion simulation module is used to analyze the kinematic characteristics of the six-link hinge mechanism. The six-link hinge mechanism is widely used in the side luggage compartment door of a large bus due to its high structural strength, small footprint, and large opening angle. The motion simulation enables the motion trajectory of the mechanism to be drawn accurately, allowing for a more intuitive and accurate analysis of the side hatch motion to prevent interference.

Motion Simulation Analysis:

To begin the motion simulation, a three-dimensional digital model of the six-link hinge mechanism is created. Each link is modeled separately, and then assembled to form the six-bar linkage. The CATIA DMU kinematics module is used to add rotating pairs to the seven rotating pins of the mechanism. A fixed pair is added to observe the motion characteristics of the other rods. The gas spring locked at point G provides the driving force for the mechanism. The rod AC is used as the driving component for the simulation. The motion model is now complete.

Motion Analysis:

The motion analysis of the support DF, to which the door lock is attached, is carried out from 0 to 120 degrees of rotation. The analysis reveals that the output of the six-bar linkage mechanism consists of translational and flipping motions. The amplitude of the translational motion is greater at the beginning and gradually reduces. To analyze the kinematic characteristics of the mechanism further, the mechanism can be simplified by decomposing the motion into two quadrilaterals. The quadrilateral aboc generates translational motion, while the quadrilateral odfe generates rotational motion.

Verification and Application:

The kinematic characteristics of the six-link hinge mechanism are verified by assembling it into the vehicle environment. The movement of the door is checked, and it is found that the hinge interferes with the sealing strip. The trajectory of the H point on the door is analyzed, and it is observed that the trajectory resembles a section of an arc moon. To solve the interference problem, the hinge design is improved by adjusting the lengths of the rods.

Improvement Effect:

After several adjustments and simulated debugging, the improved hinge demonstrates a reasonable match between the translational and rotational components. The motion trajectory is smoother, and the H point on the door moves in the same direction as the output track of the hinge. Upon full opening of the door, the gap between the H point and the side wall is within the required specifications.

The use of the CATIA DMU module for motion simulation enhances the analysis of the kinematic characteristics of the six-link hinge mechanism. The analysis allows for the improvement of the mechanism to meet the requirements of the door movement. The improved hinge demonstrates a more suitable motion trajectory and effectively reduces interference.