This study presents a comparison between the Sprint Z3 and A3 head parallel kinematics machines, distinguished by their joint sequence. The analysis focuses on performance attributes critical for precision machining specifically, parasitic motion, workspace capability, stiffness performance over the independent and parasitic spaces, and condition number distribution. Although these machines are extensively utilized in precision machining for the aerospace and automotive industries, a definitive superior choice has not been identified for machining large components. Moreover, the distribution of stiffness across the configuration of parasitic space has not previously been addressed for either mechanism. This research reveals that despite identical parameters used and exhibiting similar parasitic motions, the Sprint Z3 demonstrates superior stiffness, workspace volume, and condition number distribution. This performance advantage is attributed to variations in joint and link sequence, which enhance deflection resilience, crucial for manufacturing large-scale components. This also results in a higher condition number and a larger workspace. The result highlights the importance of design architecture in the efficacy of parallel kinematics machines and suggest

翻译：本研究对以关节序列区分的Sprint Z3与A3型并联运动机床头进行了对比分析。分析聚焦于精密加工关键性能指标：寄生运动、工作空间能力、独立空间与寄生空间内的刚度性能，以及条件数分布。尽管这两类机床在航空航天与汽车工业的精密加工中应用广泛，但在大型构件加工领域尚未明确判定更优选择。此外，针对两种机构在寄生空间构型中的刚度分布此前亦未见系统研究。本研究表明，尽管采用相同参数且呈现类似寄生运动，Sprint Z3在刚度、工作空间体积及条件数分布方面更具优势。该性能优势归因于关节与连杆序列的差异，这种差异增强了抗变形能力，对制造大型构件尤为关键，同时也带来了更高的条件数与更大的工作空间。结果凸显了设计架构在并联运动机床效能中的重要性。