Controller Design for a High Precision Elastically Supported Hybrid Active Magnetic Guidance

The design of multi coordinate drives (MCD) with nanometre positioning uncertainty and long planar motion range of several hundred millimetres is a worldwide research challenge. Ac-tive magnetic guidance (AMG) is suitable for these precision applications due to its non-contact support principle. One drawback is the heat generation due to ohmic loss in the control coil which should be minimized and kept constant to meet high precision demands [1, pp. 83-84]. In [2] an elastically supported hybrid active magnetic guidance (ES-HAMG) is proposed. A hybrid magnet combines a permanent magnet with a coil, additionally it is connected in series with a mechanical spring. This device is capable of reducing the thermal dissipation by 80% at varying load force on a sample ES-HAMG. This contribution gives a more comprehensive view on ES-HAMG inMCD than [2]. A model to estimate possible savings in power dissipation is derived in detail. The employed controller design theory is given. Experiments confirm theoretical energy savings and the nanopositioning capabilities.