Analysis and optimal synthesis of hybrid five-bar linkages

Hybrid machines are driven by two types of motors, namely the real-time non-adjustable (RTNA) motor which provides the majority of driving power and the real-time adjustable (RTA) motor which acts as a low power motion modulation device. Such a configuration has a high operational speed and high load-bearing capacity, and is relatively cheap and can provide flexibility required in many industrial applications. This paper introduces the concept of hybrid five-bar linkages for trajectory generation. A classification is made on the hybrid five-bar linkages under the condition that no dead point position exists in the linkages. The motion range of each class is then studied. An optimal synthesis scheme is put forward based on the criterion which aims at minimizing the maximum power requirement of the RTA motor for a given output motion range. A modified genetic algorithm is used to obtain the global optimal solution. Finally, an example is demonstrated to provide a justification of the proposed ideas and synthesis procedures for the hybrid five-bar linkages.