Design of Coaxial Integrated Macro–Micro Composite Actuator With Long-Stroke and High-Precision

Macro–micro composite-driving structures are widely used in many applications, and research has been done to improve the associated driving stroke and positioning accuracy. This article proposes a novel macro–micro composite actuator (MMCA) with a long-stroke and high-precision based on a voice coil motor (VCM) and giant magnetostrictive actuator (GMA). However, having a long stroke and high precision is contradictory. To verify this design scheme, the permanent magnet, coil, yoke, and other parts of the MMCA are designed and selected in detail. The axial and radial cross-sections of the macro-motion mechanism are studied using the magnetic equivalent circuit method. The force of the macro-motion coil is obtained based on finite element analysis (FEA). The results from both the FEA and practical experiments show the simulation results are consistent with the theoretical predictions. The maximum force of the MMCA is 53 N, the maximum displacement is 47 mm, the maximum positioning error is only
$0.14~\mu \text{m}$
, and the maximum acceleration is approximately
$6.7g$
, which lays a theoretical and technical foundation to provide a high-performance actuator in the field of precision manufacturing.