The present invention relates to a low-inductance electromagnetic drive without driving magnetic flux circuit, which comprises a magnetic pole, a drive coil, an upper magnetic inductive board, a permanent magnet and a lower magnetic-inductive board. For example, an apparatus may include a signal strength determination module, a motion determination module, and a handoff controller. The invention provides for direct body contact by an ultrasound imaging head, as well as targeted ultrasound imaging of a selected portion of the region from which x-ray images are obtained. A gas-permeable, liquid-impermeable membrane is placed in the gas flow passage.