Electromagnetic PCB crossroads topologies for automation track systems

A vessel transport system in a liquid handler system comprising:

• one or more vessel movers configured to transport a sample vessel and having a magnetic base;
• a track configured to provide a selective magnetic field to propel the magnetic base of each vessel mover along the track, the track comprising a plurality of multilayer printed circuit boards (PCB) arranged along a transport path, each PCB having a plurality of multi-layer conductive coils within layers of the PCB, each coil comprising a plurality of single-layer spirals electrically coupled with one another to form a multilayer coil, wherein each of the plurality of conductive coils comprises at least twelve single-layer spirals, and each spiral comprises at least twelve turns;
• and
• a processor configured to control selective application of currents to the plurality of multi-layer coils to create the selective magnetic field,
• wherein at least a subset of the plurality of multi-layer conductive coils are stacked relative to one another below a surface of the track, such that the selective application of currents selects one of a plurality of branching paths along the track.