A distinction can be made based on motion range (“long” indicating meter-scale, “short” indicating mm scale), and accuracy (micrometer or sub-nanometer). Long-range actuators typically have a moderate accuracy but suffer from nonlinearities like friction, requiring compensation methods using adaptive or learning techniques. Nonlinearities also play a role when using piezo materials for actuation in high-accuracy applications, possibly simultaneously with using the material as sensor (“self-sensing”). Finally, control techniques to improve sub-nanometer positioning systems have to deal with position dependency, in particular in the observation of dynamic modes in the measurement system. This has led to position-dependent observers creating the option of increasing control bandwidth.
Meet some of our Researchers
Clarisse Bosman Barros
Most important projects
- Nanometer Accurate Positioning System (NAPAS) having the goal of creating a long-stroke planar actuator with nanometer accuracy, using modelling and control techniques to reduce quasi-static deformations as well as position-dependent resonant behavior.
- Impulse Feedforward techniques for time-varying positioning systems, in collaboration with ASML and Mechanical Engineering department.
- Advanced Large range Piezo stage (ALP) Creating a piezo-driven wafer stage, in collaboration with HTSC and ASML.
Our most recent peer reviewed publications
Corrigendum to “the Minkowski–Lyapunov equation for linear dynamicsAutomatica (2019)
Mixed feedback and feedforward control design for multi-axis vibration isolation systemsMechatronics (2019)
A distributed optimization approach for complete vehicle energy managementIEEE Transactions on Control Systems Technology (2019)
Optimal Hankel norm model reduction for discrete-time descriptor systemsJournal of the Franklin Institute (2019)
Constrained order observer design for disturbance decoupled output estimationIEEE Control Systems Letters (2019)