In context
In 2024, precision positioning in micro/nano manipulation demanded rotary stages with large angles, high resolution, and high load capacity in compact form. Traditional stages using ball screws or voice coils were bulky and limited in speed, while existing piezoelectric stick-slip designs often required multiple actuators, creating driving redundancy and control complexity.
What was reported
Researchers at Ningbo University and Zhejiang University designed a purely central stick-slip rotary stage driven by a single piezoelectric actuator, eliminating driving redundancy. The stage uses a bridge-type compliant mechanism with hybrid straight-circular and leaf-type flexure hinges, featuring a pair of centrosymmetric driving feet that clamp and release a circular slide to produce rotation. The bridge mechanism magnifies the clamping force, which can be tuned by adjusting the tilt angle α.
Theoretical analysis using pseudo-rigid-body method and finite element simulations validated the force amplification. Experiments on an 86 mm × 86 mm × 32 mm prototype showed a maximum load of 9 kg at 150 V input, an angular resolution of 0.10 μrad, and an optimal driving frequency of 500 Hz. The rotation speed increased nearly linearly with voltage above 21 V, enabling linear control.
Step repeatability error was 7.8% at 60 V, improving at higher voltages. The design avoids actuator redundancy by using a single actuator, simplifying assembly and control while maintaining high load capacity.
Why it mattered
This work addressed the trade-off between load capacity and structural simplicity in piezoelectric rotary stages, offering a compact solution for precision posture adjustment in applications such as cell puncture, micro-rotation positioning, and adaptive optics. The force-magnifying bridge mechanism could inspire further designs for high-load, high-resolution micro/nano positioning systems.
“The rotary stage achieves non-redundant, purely central rotation while magnifying the clamping force.”
Source: 《机器人》期刊 (robot.sia.cn) · Published 2024-05-08 · “无驱动冗余的纯中心压电黏滑旋转台”