# Investigation on active vibration isolation of a stewart platform with piezoelectric actuators - My digital brain
Tags Stewart Platforms, Vibration Isolation, Flexible Joints Reference (Wang {\it et al.}, 2016) Author(s) Wang, C., Xie, X., Chen, Y., &amp; Zhang, Z. Year 2016 Model of the Stewart platform: Struts are treated as flexible beams Payload and the base are treated as flexible plates The FRF synthesis method permits to derive FRFs of the Stewart platform The model is compared with a Finite Element model and is shown to give the same results.
Author: — Thomas Dehaeze

# Investigation on active vibration isolation of a stewart platform with piezoelectric actuators

Tags
  Stewart Platforms, Vibration Isolation, Flexible Joints
Reference
  (Wang {\it et al.}, 2016)
Author(s)
  Wang, C., Xie, X., Chen, Y., & Zhang, Z.
Year
  2016

Model of the Stewart platform:

- Struts are treated as flexible beams
- Payload and the base are treated as flexible plates
- The FRF synthesis method permits to derive FRFs of the Stewart platform

The model is compared with a Finite Element model and is shown to give the same results. The proposed model is thus effective.

Figure 1: Stewart Platform

Control: Combines:

- the FxLMS-based adaptive inverse control => suppress transmission of periodic vibrations
- direct feedback of integrated forces => dampen vibration of inherent modes and thus reduce random vibrations

Force Feedback (Figure 2).

- the force sensor is mounted between the base and the strut

Figure 2: Feedback of integrated forces in the platform

Sorts of HAC-LAC control:

- LAC: Decentralized integral force feedback
- HAC: Inertial control using accelerometers. Use of the Jacobian to decouple the motion and then Fx-LMS based adaptive control is used

Experimental validation:

- All 6 transfer function from actuator force to force sensors are almost the same (gain offset)
- Effectiveness of control methods are shown

# Bibliography

Wang, C., Xie, X., Chen, Y., & Zhang, Z., Investigation on active vibration isolation of a stewart platform with piezoelectric actuators, Journal of Sound and Vibration, 383(), 1–19 (2016). http://dx.doi.org/10.1016/j.jsv.2016.07.021 ↩