Xu Zhaotang.Solution Method of Common Constraint of the Mechanism in the Modified G-K's Formula[J].Journal of Mechanical Transmission,2023,47(04):74-78.
Xu Zhaotang.Solution Method of Common Constraint of the Mechanism in the Modified G-K's Formula[J].Journal of Mechanical Transmission,2023,47(04):74-78. DOI: 10.16578/j.issn.1004.2539.2023.04.011.
Solution Method of Common Constraint of the Mechanism in the Modified G-K's Formula
In the calculation of mobility of the mechanism using the modified Grübler-Kutzbach's formula of mechanism mobility
the common constraint of the mechanism has to be solved. In order to obtain the common constraint of the mechanism with a simpler method and on the basis of defining the common constraint of the mechanism
the coordinate direction of the mechanism without common constraint is obtained according to the mobility of kinematic pair and the constraint direction of the kinematic pair whose absolute motion is not zero
and then the common constraint of the mechanism is determined in other coordinate direction. The total number of coordinate directions with and without the common constraint of the mechanism is 6. The common constraint of the mechanism is equal to the number of coordinate directions with common constraint. This method does not need the screw theory to solve the common constraints of the mechanism
which is convenient for engineering and technical personnel to solve the common constraints of the mechanism. It is also convenient for the modified Grübler-Kutzbach's formula of the mechanism mobility to be popularized and applied in engineering and technical personnel.
关键词
机构自由度公共约束运动副的自由度运动副的绝对运动坐标方向
Keywords
MechanismMobilityCommon constraintMobility of kinematic pairAbsolute motion of kinematic pairCoordinate direction
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