混合驱动连杆机构的串行和并行设计

SEQUENTIAL AND CONCURRENT DESIGN OF LINKAGES MECHANISM WITH HYBRID ACTUATORS

混合驱动机构的设计包括运动设计、动力设计和控制设计三个方面。一方面,这些设计相互影响和关联,具有非常强的耦合关系。另一方面,各个设计方面的设计准则、设计目标却有所差别。串行设计是先进行机构的运动设计、动力设计,最后再进行控制设计。并行设计是将机构的运动设计、动力设计和控制设计一并考虑进行设计。对于混合驱动平面五杆机构,分别采用串行设计和并行设计等不同的设计策略,尽管设计所采用的优化方法都是微分进化方法,但是设计结果却有所不同。串行设计可以达到较高的机构运动要求,但控制系统的设计比较困难,而且控制效果不好。并行设计得到的设计结果是机构的运动控制效果得以改善,但是设计的数学模型变得复杂,机构的运动精度有所下降。

The design of a linkage with hybrid actuators involves three aspects. They are kinematic design, dynamic design and control design. On one hand, each of the aspects affects and relates to others. They are strongly coupled. On the other hand, they are different in design criteria and decision objective as well. In sequential design, the kinematic design is completed firstly, then the dynamic design, and finally the control design. Whereas in concurrent design, the optimizations of the three aspects are considered simultaneously. The sequential and concurrent designs of five-bar mechanism with hybrid actuators are developed. Even though the differential evolution algorithm is employed as the optimization tool in all cases, the results from the sequential and concurrent designs are different. It is shown that the sequential design leads to more accuracy in kinematics, but the control design is more difficult and the performance of control system is not good. By contrast, the concurrent design enables the control design to be easy and the performance is improved apparently at the expense of more complex design model and the loss of accuracy in kinematics.